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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South China

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Science China Earth Sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2. TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. Nanjing institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, China 2. Henan institute of Geological Survey, Zhengzhou 450007, China 3. State Key Laboratory of Geological Processes and {2. {3. at China University of Geosciences, Wuhan 43.074, China 4. Faculty of Material Sciences and Chemical Engineering, China University of Geosciences, Wuhan 43.074, China 1. Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and mineral resources at China University of Geosciences Wuhan 430074 China 4. Faculty of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South China, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

Metallogenic characteristics of epithermal gold deposits in Tianshan, Xinjiang, China

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Chinese Science Bulletin 1999年第S2期44卷 138-139页

作者： FENG Jianzhong~1, FU Shuixing~2. WU Dewen~3.and YANG Zian~3.1. Department of Geology, Peking University, Beijing 100871, China 2. Beijing institute of Geology for {3. {2., Beijing 100012. China 3. Center of Remote Sensing for Geology, CNNC, Beijing 101601, China Department of Geology Peking University Beijing 100871 China Beijing institute of Geology for mineral {2. Beijing 100012 China Center of Remote Sensing for Geology CNNC Beijing 101601 China

TIANSHAN in southern Xinjiang belongs to the Paleozoic island arc system in which volcanic rocks are extensively distributed. A series of epithermal gold deposits such as the Axi, Xitan, Cuiling andShuangfengshan gold deposits have been discovered. 1 Geological settings of epithermal gold deposits in Tianshan, southern Xinjiang Tianshan in southern Xinjiang belongs to the Paleozoic island arc system. To its north is the Kazakhstan plate, and to its north is the Tarim plate. From west to east, the tectonic units are characterizedby Yili island arc, southern Tianshan arc-basin, Jiaoluotage island arc and Xingxingxia island arc. TheEW-trending Tianshan ore belt is controlled by Kanggurtag geosuture. In its west part, it is controlled byShenglidaban geosuture. The linear structure is NNW-trending; from north to south, the faults

关键词： metallogenic characteristics gold deposits Tianshan Xinjiang.

Relationships Between the North China Plate and the Tarim Plate

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Acta Geologica Sinica(English Edition) 1994年第2期68卷 109-124,226页

作者： Wang Tingyin, Wang Jinrong, Liu Jinkun, D epartment of Geology, Lanzhou U niversity, Lanzhou, GansuWang Shizheng, Ningxia Bureau of Geology and mineral resources, Yinchuan, Ningxiaand Wu Jiahong {2. {3. of Geology and mineral resources, {2., Liaoning Department of Geology Lanzhou University Lanzhou Gansu China

The relationships and boundary between the North China and Tarim plates have been unclear for a long time ; however, the two plates occupy a prominent position in the formation and evolution of the continental lithosphere of China. It is proposed that the Engger Us ophiolitic melange zone discovered recently north of Alaxa is a typical suture between the two plates. The ophiolitic melange zone is composed mainly of a mixture of fragments of ancient oceanic crust and sedimentary rocks of active and passive continental margins. The melange may be divided into tectonic inclusions and matrix. The suture extends northeastwards into the Republic of Mongolia and probably westwards to meet the Altun fault. With the Engger Us ophiolitic melange zone as the boundary the Alaxa area may be divided into two parts: the northern part (AN ) belongs to the Tarim plate, while the southern part (AS) the North China plate. Geological evidence shows that the two plates were amalgamated in the Late Permian or a bit later.

关键词： North China plate Tarim plate ophiolitic melange tectonic evolution

The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science China(Technological Sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1, LIU Changming1,2. WANG Yu3.& WANG Hongrui1 1. Beijing Normal University, Beijing 100875, China 2. institute of Geographic Science and Natural {3., Chinese Academy of Sciences, Beijing 100101, China 3. Reconnaissance, Planning, Design and Research institute, YRCC, Zhengzhou 450003. China Beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

Debris Flow Hazard Assessment Based on Support Vector Machine

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3. 1. institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China 3. institute of Geographical Sciences and Natural {2. Research, Chinese Academy of Sciences, Beijing 100101, China institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of Chinese Academy of Sciences 100049 Beijing China institute of Geographical Sciences Natural resources Research Chinese Academy of Sciences 100101 Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 3. debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

2.5-dimensional angle potential field algorithm for the real-time autonomous navigation of outdoor mobile robots

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Science China(Information Sciences) 2011年第10期54卷 2100-2112页

作者： QIU Quan 1,3.& HAN JianDa 2.1 Beijing Research Center of Intelligent Equipment for Agriculture,Beijing 100097,China 2.State Key Laboratory of Robotics,shenyang {3. of Automation,Chinese Academy of Sciences,shenyang 110016,China 3.National Research Center for Intelligent Agricultural Equipment,Beijing 100097,China 1. Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097 China3. National Research Center for Intelligent Agricultural Equipment Beijing 100097 China2. State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

A new real-time algorithm for the autonomous navigation of mobile robots equipped with laser scanners is proposed in this *** from the existing algorithms designed for 2.dimensional navigation problems,the new algorithm introduces the height information of the obstacles into the guidance process and behaves as a 2.5-dimensional angle potential field algorithm (2.5D-APF) to fulfill the navigation requirements under complex outdoor terrain ***,one laser scan is partitioned into two kinds of function sectors: guidance sector and inspecting ***,the guidance sector and the inspecting sectors are reconstructed to form a virtual guidance scan,where the 2.5D information is taken into ***,the conventional APF is improved to analyze the virtual guidance scan and generate the navigation *** new algorithm is tested on a tracked mobile robot,and the experimental results validate the proposed algorithm.

关键词： robot 2.5-dimensional outdoor real-time autonomous navigation

N_2. emissions from agricultural soils in the North China Plain: the effect of chemical nitrogen fertilizer and organic manure

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Journal of Environmental Sciences 2000年第4期12卷 463-468页

作者： DONG Yun\|she 1,2.3., Dieter Scharffe 2. Manfred Domroes 3. QI Yu chun 1, ZHANG Shen 1 (1. institute of Geographic Sciences and Natural {3. Research, Chinese Academy of Sciences, Beijing 100101, China E\|mail: dongys@*** 2. M 中科院地理科学与资源所北京 1 0 0 1 0 Max- Planck-institute of Chemistry 德国 Mainz 550 2 0 Mainz University 德国 Mainz 550 99

An enclosed chamber technique was used to measure N 2. emissions from intensively agricultural soils of the North China Plain during the periods of 1995—1996 and 1997—1998, to reflect distinct components of winter wheat and summer maize growing seasons. The results showed that the continuous application of fertilizer in agricultural soils increased N\-2. emissions by a factor of 2..1—2..1, the calculated annual chemical N fertilizer\|transformed N\-2.\|N emissions was 0.67%. Our results indicated that the application of organic manure also had a significant influence on soil N 2. emissions, which combined with the use of chemical N increased about 2.% in a year. It was calculated that there were about 0.11% N of organic manure transformed as N 2. N. Annual mean N 2. emission from our study area of fertilized soils was estimated to be 57.1 μgN 2./(m 2.h). A weak correlation was also found between N 2. emissions and soil available nitrogen content NH + 4.

关键词： N_2. emissions the North China Plain agricultural soils chemical nitrogen organic manure

In situ experiments on width and evolution characteristics of excavation damaged zone in deeply buried tunnels

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Science China(Technological Sciences) 2011年第S1期54卷 167-174页

作者： LI ShaoJun 1,FENG XiaTing 1,LI ZhanHai 3.CHEN BingRui 1,JIANG Quan 1,WU ShiYong 2.HU Bin 2.&XU JinSong 2.1 State Key Laboratory of Geomechanics and Geotechinical Engineering,{3. of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 43.071,China 2.Ertan Hydropower Development Company,Ltd.,Chengdu 610051,China 3.School of resources and Civil Engineering,Northeastern University,{2. 110004,China 1. State Key Laboratory of Geomechanics and Geotechinical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China2. Ertan Hydropower Development Company Ltd. Chengdu 610051 China

The seven long tunnels of Jinping II hydropower station are deeply *** width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and *** order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this *** borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were *** paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled *** properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel *** width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two *** relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as *** results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.

关键词： deeply buried tunnel excavation damaged zone evolution characteristics in situ experiments

A New Admissibility Condition of Discrete-time Singular Systems with Time-varying Delays

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International Journal of Automation and computing 2012年第5期9卷 480-486页

作者： Yong-Yun Shao 1,3.Xiao-Dong Liu 1,2.Xin Sun 3.Zhan Su 4 1 Transportation Management College, Dalian Maritime University, Dalian 11602., China 2.Department of Mathematics, Dalian Maritime University, Dalian 11602., China 3.Department of Computer and Mathematics Teaching, shenyang Normal University, shenyang 11003., China 4 {2. of Systems Science, Northeastern University, shenyang 110004, China 1. Transportation Management College Dalian Maritime University Dalian 116026 China 3. Department of Computer and Mathematics Teaching Shenyang Normal University Shenyang 110034 China 2. Department of Mathematics Dalian Maritime University Dalian 116026 China 4. institute of Systems Science Northeastern University Shenyang 110004 China

This paper gives a novel delay-dependent admissibility condition of discrete-time singular systems with time-varying delays. For convenience, the time-varying delay is assumed to be the sum of delay lower bound and the integral multiples of a constant delay. Specially, if the constant delay is of unit length, the delay is an interval-like time-varying delay. The proposed admissibility condition is presented and expressed in terms of linear matrix inequality (LMI) by Lyapunov approach. Generally, the uncertainty of time-varying delay would lead to conservatism. In this paper, this critical issue is tackled by accurately estimating the time-varying delay. Consequently, the proposed admissibility condition is less conservative than the existing results, which is demonstrated by a numerical example.

关键词： Singular systems discrete-time delay-dependent admissibility time-varying delay