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Artificial Neural Network Model for Discrimination of Stability of Ancient Landslide in Impounding Area of Three Gorges Project, china

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Journal of china University of geosciences 2003年第2期14卷 161-165页

作者： Zhou Pinggen china institute of geo environment {3., beijing 100081 china institute of geo-environment {3. Beijing 100081

The factors of geomorphology, geological setting, effect of ground water and environment dynamic factors (e.g. rainfall and artificial water recharge) should be integrated in the discrimination of the stability of the ancient landslide. As the criterion of landslide stability has been studied, the artificial neural network model was then applied to discriminate the stability of the ancient landslide in the impounding area of the Three Gorges project on the Yangtze River, china. The model has the property of self adaptive identifying and integrating complex qualitative factors and quantitative factors. The results of the artificial neural network model are coincided well with what were gained by classical limit equilibrium analysis (the Bishop method and Janbu method) and by other comprehensive discrimination methods.

关键词： ancient landslide stability artificial neural network model the Three Gorges.

Have a correct understanding of the attribute of geologic environmentgive full play to the role of geoscience in environmental protection

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Journal of environmental Sciences 1995年第4期7卷 491-501页

作者： Ha Chengyou(institute of environmental geology, Ministry of geology and Mineral Resources, beijing 100081 , china)

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关键词： geologic environment attribute geologic resources geologic capacity geologic disaster.

Inertial theory of the mean Hadley circulation under the condition of nonstatic equilibrium

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Science china Earth Sciences 2006年第5期49卷 546-553页

作者： CHAO Jiping1 & LIU Fei2,3.1. National Marine environmental Forecasting Center, beijing 100081, china 2. Key Laboratory Regional Climate-Environment for Temperate East Asia, {3. of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 3. Graduate University of Chinese Academy of Sciences, beijing 100049, china National Marine environmental Forecasting Center Beijing China Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China

Tropical atmosphere is divided into two layers, the layer near the ground is the planet boundary layer, where the motion is linear, if the radiation equilibrium temperature is given at the top of the boundary layer, the vertical motion there can be obtained. It is the non-viscous ideal atmos- pheric layer above the boundary one, where the motion is nonlinear. After getting the conservation laws of angular momentum, potential temperature and potential vortex, the inertial theory of the Hadley circulation driven by the vertical motion of the boundary layer is established, followed by sev- eral examples of its application.

关键词： Hadley circulation, inertial theory, conservation laws of angular momentum, potential temperature and potential vortex.

Report on Cardiovascular Health and Diseases in china 2023.An Updated Summary

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Biomedical and environmental Sciences 2024年第9期37卷 949-992页

作者： National Center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in china Shengshou Hu .

Since 1990,china has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among Chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of Chinese *** terms of the proportions of disease mortality among urban and rural residents in china,CVD has persistently ranked *** 2021,CVD accounted for 48.98%and 47.3.%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health institute and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National Center for Cardiovascular Diseases has organized experts from relevant fields across china to compile the“Report on Cardiovascular Health and Diseases in china”annually since *** 2024 report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National Center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in china.

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

Study on environmental Health Strategy after Earthquake

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Biomedical and environmental Sciences 1989年第4期2卷 331-334页

作者： YUE LIN institute of environmental Health monitoring,Chinese Academy of Preventive Medicine,{3. 100050,china institute of environmental Health monitoring Chinese Academy of Preventive Medicine Beijing China.

The first task in prevention of diseases after an earthquake is to quickly provide an adequate source of safe drinking ***,the incidence of infectious intestinal diseases in the disaster area residents will increase *** health measures,such as disinfecting drinking water,protecting the water source,and treating disaster area residents,must be taken at the same *** sensory test of meat is a useful index of meat decomposition *** alkali is a kind of toxic chemical,and personal protective measures must be taken in handling *** general,all of these measures are important not only for achieving the goal of“no severe epidemic after strong earthquake disaster”in the affected areas,but also for enriching knowledge of disaster medicine.1989 Academic ***.

关键词： Study on environmental Health Strategy after Earthquake

environmental　risk　assessment　of　the　middle　route　of　south－to－north　water　transferring　source　project　in　china

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Journal of environmental Sciences 1996年第3期8卷 285-291页

作者： Wang Huadong Wang Fei(institute of environmental Sciences,beijing Normal University, beijing 100875, china) institute of environmental Sciences Beijing Normal University Beijing 100875 China

This paper focused on the environment risk of the middle route of south-to-north water transferring source project in china. Analytic hierarchy process was applied to risk identification,fuzzy probability-fault tree analysis to risk probability assessment,statistics and analogy process to risk consequences assessment, lastly, grey relevant analysis and comprehensive index process to risk impact evaluation. The main environment risk accident of the project is dam failure, the main causative factors of the accident are catastrophic flood and wrecking earthquake. The flash flood, due to dam failure, will impact on nature, society and economy. The major environment risk areas are Jingzhou and Xiangfan,Hubei Province. The environment risk management measures should be adopted in order to ensure the safety of the project-environment complex system.

关键词： water source project environment risk risk assessment

Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3.& XU Daoyi4 1. Research institute of Petroleum Exploration and Development, beijing 100083. china 2. Key Laboratory of Oil and Gas Reservoir of Petro{3., beijing 100083. china 3. china University of geosciences, beijing 100083. china 4. institute of geology, china Earthquake Administration, beijing 100029, china Research institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china University of geosciences Beijing China institute of geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

Debating about the climate warming

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Progress in Natural Science:Materials International 2006年第1期16卷 1-6页

作者： WANG Shaowu1, LUO Yong2, ZHAO Zongci2, DONG Wenje2 and YANG Bao3.(1.Department of Atmospheric Sciences, School of Physics, Peking University, beijing 100871, china 2. Laboratory for Climate Studies, china Meteorological Administration,{3., china 3. institute of Cold and Arid Regions environmental and Engineering, Chinese Academy of Sciences, Lanzhou 73.000, china) Department of Atmospheric Sciences School of Physics Peking University Beijing 100871 China Laboratory for Climate Studies China Meteorological Administration Beijing 100081 China institute of Cold and Arid Regions environmental and Engineering Chinese Academy of Sciences Lanzhou 730000 China

Debating about the climate warming is reviewed. Discussions have focused on the validity of the temperature reconstruction for the last millennium made by Mann et al. Arguments against and for the reconstruction are introduced. Temperature reconstructions by other authors are examined, including the one carried out by Wang et al. in 1996. It is concluded that: (1) Ability of reproducing temperature variability of time scale less than 10 a is limited, so no sufficient evidence proves that the 1990s was the warmest decade, and 1998 was the warmest year over the last millennium. (2) All of the temperature reconstructions by different authors demonstrate the occurrence of the MWP (Medieval Warm Period) and LIA (Little Ice Age) in low frequency band of temperature variations, though the peak in the MWP and trough in LIA varies from one reconstruction to the others. Therefore, terms of MWP and LIA can be used in studies of climate change. (3. The warming from 1975 to 2000 was significant, but we do not know if it was the strongest for the last millennium, which needs to be proved by more evidence.

关键词： climate warming MWP LIA the 20th century.

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

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Chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU Fei1,2 & CHAO JiPing3.4 1 institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2 Graduate University of Chinese Academy of Sciences, beijing 100049, china 3.National Marine environmental Forecasting Center, beijing 100081, china 4 First institute of Oceanography, State Oceanic Administration of china, Qingdao 266061, china institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China National Marine environmental Forecasting Center Beijing China First institute of Oceanography State Oceanic Administration of China Qingdao China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件