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Scenario simulation and forecast of land use/cover in northern China

Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3.& HE ChunYang 3.1 {2. of Geographical science, Chongqing {2. {3., Chongqing 400047, China 2.{2. of resources and Environmental science, Chongqing {3., Chongqing 400044, China 3.{2. of resources science & technology, beijing normal university,{13., China college of Geographical science Chongqing Normal University Chongqing 400047 China college of resources and Environmental {2. Chongqing University Chongqing 400044 China college of resources {2. & {3. Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern China in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern China.

关键词：土地利用中国北方细胞自动机系统动力学

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Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science China(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2. LIN Xin3.& ZENG WenYi4 1 college of Water {2., Key Laboratory for Water and Sediment {2.s of the Ministry of Education,{3., beijing 100875, China 2.School of {2., beijing Institute of Education, beijing 100011, China 3.School of Mathematical {2.s,{3., beijing 100875, China 4 college of Information {2. and {13.,{3., beijing 100875, China 1. college of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical sciences Beijing Normal University Beijing 100875 China 4. college of Information science and {2. Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2.04) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. resources and Environmental School, Lanzhou {2., Lanzhou 73.000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of {2.s, Lanzhou 73.000, China {3., beijing normal university, beijing 100875, China 1. resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. college of resources science & technology Beijing Normal University Beijing 100875 China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2.1. Key Laboratory of Beam technology and Material Modification of Ministry of Education,{2.,{2., China 2. Physics Department,{2.,{2., China 3. China Institute of Atomic Energy, beijing 102.13. China Key Laboratory of Beam technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics Department Beijing Normal University Beijing 100875 China China Institute of Atomic Energy Beijing 102413 China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(3.Si,4n)2.0Hs, 2.0}U(3.S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.0}U(3.S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

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Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

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science China Earth sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, beijing normal university college of {2. {3. & technology, beijing normal university, beijing 100875, China 1. Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China 2. college of resources {2. & {3. Beijing Normal University 100875 Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern China in the next 2. years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern China suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern China in the next 2. years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2. WU Li-xin1, 2. LI Hui-ying3.1. college of {2. and Civil Engineering, Northeastern {2., Shenyang 110004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education,{3., beijing 100875, China 3. college of Computer science and technology, Jilin {2., Changchun 13.012. China [a] college of resources and Civil Engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer science and {2. Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3. scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3. mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

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A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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science China(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2.2.& ZHAO Weimin3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic science and Natural {2. Research, Chinese Academy of sciences, {3. 100101, China 2. Institute of Environmental science, beijing normal university, beijing 100875, China 3. Water {2. Conservation Committee of Yellow River, Zhengzhou 450003. China Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2. WANG Chuan1, DENG Zhiwei3. LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua university, {2. 100084,China 2. Department of Materials {2. and Engineering,{3., beijing 100875, China 3. Testing and Analytical Center,{3., beijing 100875,China 4. Department of Physics,{3., beijing 100875, China 5. Key Laboratory For atomic and Molecular Nano{2.s, Tsinghua university, {2. 100084,China 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. Department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. Department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2.+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

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The toxicity of Cu^(2.) to Microcystis aeruginosa using dielectric spectroscopy

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science China Chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2.1college of Chemistry,beijing {2. {3.,beijing 100875,China 2.0} of Life science,beijing {2. {3.,beijing 100875,China 1. college of Chemistry Beijing Normal University Beijing 100875 China2. College of Life Science Beijing Normal University Beijing 100875 China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2. solution to Microcystis *** was found that 0.04 mM Cu2. had no effect on dielectric increment,whereas the Cu2. concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2. on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2. at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2. or Mg2. did not protect *** cells from 1 mM Cu2. *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

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Edaphic factors determining variation of two ecotypes of Leymus chinensis in North China

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Progress in Natural science:Materials International 2006年第11期16卷 1150-1155页

作者： ZHOU Chan~1 and YANG Yunfei~2.*(1. MOE Key Laboratory of Environmental Change and Natural Disasters, college of resources {2. and {3., beijing normal university, beijing 100875, China 2. Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland {2., Northeast normal university, Changchun 13.02., China) [a]MOE Key Laboratory of Environmental Change and Natural Disasters College of Resources Science and Technology Beijing Normal University Beijing China [b]Key Laboratory of Vegetation Ecology Ministry of Education Institute of Grassland Science Northeast Normal University Changchun China

To identify ecotypic variation of L. chinensis, the physiological characteristics and environmental factors were measured and assessed for grey-green and yellow-green ecotypes of L. chinensis grown in the salt-alkalized and aeolian sandy soils. Although both ecotypes presented a similar salt-alkaline tolerance under the experimental conditions, they differed in several aspects. The L. chinensis grown in the aeolian sandy soils had higher water potential and chlorophyll content and lower proline content in their leaves than those grown in the salt-alkalized habitat, and the grey-green ecotype of L. chinensis in both types of soils had higher water potential, chlorophyll and proline contents than the yellow-green ecotype. Besides, grey-green ecotypes had higher salt-alkaline tolerance than the yellow-green ecotype. The stepwise regression analysis showed that soil conductance and pH value were the main ecological factors affecting the physiology of L. chinensis. From the natural distribution of the two ecotypes, we considered that salt-alkaline in the soils is the leading factor in determining ecotypic variation of L. chinensis. The two ecotypes were first named grey-green and yellow-green ecotypes respectively.

关键词： L.chinensis ecotype adaptability variation ecological factor salt-alkaline in soil.

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