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

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 {1., Beijing 1.0875, china 2. Institute of Geographic Science and Natural resources, Chinese Academy of Sciences, Beijing 1.01.1. 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 1.%; when precipitation decreases by 1.%, 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 1.%. Under this condition, the simulated average annual runoff decreases by 1..8%. On the contrary, scenario 1.is the best to the enhancement of runoff; i.e. when temperature decreases 1.℃ precipitation will increase by 1.%, which will make the annual runoff of Sanmenxia increase by 1..6%.

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

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A computational investigation of boron-doped chromium and chromium clusters by density functional theory

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 812-817页

作者： GE GuiXian1.JING Qun1.& LUO YouHua2,3 1.Key Laboratory of Ecophysics and Department of Physics,normal College,Shihezi {1.,Xinjiang 832003,china 2 school of Science,East china {1. of Science and Technology,Shanghai 200237,china 3 Institute of Theoretical Physics,school of Physics and Information Optoelectronics,Henan {1.,Kaifeng 475004,china 1. Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Xinjiang 832003 China2. School of Science East China University of Science and Technology Shanghai 200237 China3. Institute of Theoretical Physics School of Physics and Information Optoelectronics Henan University Kaifeng 475004 China

The geometries,stabilities and electronic properties of Crn and CrnB(n=2-9) clusters have been systematically investigated by density functional *** results suggest that the lowest energy structures for CrnB clusters can be obtained by substituting one Cr atom in Crn+1.clusters with B *** geometries of CrnB clusters are similar to that of Crn+1.clusters except for local structural *** second-order difference and fragmentation energy show Cr4,Cr6,Cr8,Cr3B,Cr5B and Cr8B cluster are the most stable among these studied *** impurity B increases the stabilities of chromium *** B is doped on the Crn clusters,cluster geometry does dominate positive role in enhancing their *** doped B atom does not change the coupling way of the Cr site in Crn clusters,but breaks the symmetry and the Cr atoms are no longer *** doped B atom increases the total magnetic moments of Crn in most cases.

关键词： Crn and CrnB clusters geometries electronic properties

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Density functional theory study on the structural and electronic properties of Ag-adsorbed (MgO)_n clusters

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 734-741页

作者： GE GuiXian1. JING Qun1.& LUO YouHua2,3 1.Key Laboratory of Ecophysics and Department of Physics, normal College, Shihezi {1., Shihezi 832003, china 2 school of Science, East china {1. of Science and Technology, Shanghai 200237, china 3 Institute for Theoretical Physics, Henan {1., Kaifeng 475004, china Key Laboratory of Ecophysics and Department of Physics Normal College Shihezi University Shihezi 832003 China school of Science East China University of Science and Technology Shanghai 200237 China Institute for Theoretical Physics Henan University Kaifeng 475004 China

Equilibrium geometries, charge distributions, stabilities and electronic properties of the Ag-adsorbed (MgO)n (n = 1.8) clusters have been investigated by density functional theory (DFT) with generalized gradient approximation (GGA) for exchange-correlation functional. The results show that hollow site is energetically preferred for n≥4, and the incoming Ag atoms tend to cluster on the existing Ag cluster. The Mulliken populations indicate that the interaction between the Ag atom and Magnesia clusters is mainly induced by a weak atomic polarization. The adsorbed Ag atom only causes charge redistributions of the atoms near itself. The effect of the adsorbed Ag atom on the bonding natures and structural features of Magnesia clusters is minor. Furthermore, the investigations on the first energy difference, fragmentation energies and electron affinities show that the Ag(MgO)4 and Ag(MgO)6 are the most stable among studied clusters.

关键词： Ag (MgO)_n clusters geometries electronic properties

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Extraction of vegetation fraction information from CBERS images based on VBSI vegetation index in Kaixian county

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中国有色金属学会会刊：英文版 2011年第S3期21卷 712-716页

作者： GAO Zhi-fang1. NIU Hai-peng1. LIU Jin-ping2 1. College of Surveying and land Information Engineering, Henan Polytechnic {1., Jiaozuo 454000, china 2. College of Geographic Sciences, Chongqing normal {1., Chongqing 400047, china [a] College of Surveying and land Information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] College of Geographic Sciences Chongqing Normal University Chongqing 400047 China

Based on the mixed pixel model, the vegetation fraction of Kaixian county, china, was extracted with three free CBERS images. VBSI vegetation index suitable for CBERS images constructed with FCD (forest canopy density) model principle was put forward by ITTO (International Tropical Timber Organization) was used, considering the underestimation of vegetation fraction using NDVI in low mountain-hill region influenced by soils and shadows. And vegetation fraction was divided into five categories from low to high in order to study the special variation of vegetation cover. The results show that the vegetation cover of the region is overall good, with an average of 50%. The area of vegetation fraction below 30% accounts for 1..7% of the entire studied area, mainly concentrates in central eastern Kaixian county, where is the major development zone of cities and towns; that between 30% and 60% accounts for 62%; and that higher than 60% accounts for 26%, and mostly locates in northern middle-mountain area.

关键词： VBSI vegetation index mixed pixel model FCD model CBERS

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Characterization for commutators of n-dimensional fractional Hardy operators

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Science china Mathematics 2007年第10期50卷 1418-1426页

作者： Zun-wei FU~(1.2) Zong-guang LIU~3 Shan-zhen LU~(1.) Hong-bin WANG~3 ~1.school of Mathematical Sciences,Beijing {1. university,Beijing 1.0875,china ~2 Department of Mathematics,Linyi {1. university,Linyi 276005,china ~3 Department of Mathematics,china university of Mining and Technology (Beijing),Beijing 1.0083,china 1. school of Mathematical Sciences Beijing Normal University Beijing 100875 China 2. Department of Mathematics Linyi Normal University Linyi 276005 China 3. Department of Mathematics China University of Mining and Technology (Beijing) Beijing 100083 China

In this paper,it was proved that the commutator H_(β,b)generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from L^(p1.(R^n)to L^(p2)(R^n)if and only if b is a CMO(R^n)function,where 1.p1.1.p2=β/n,1.p1.∞,0≤β<***, the characterization of H_(β,b)on the homogenous Herz space K_q^(α,p)(R^n)was obtained.

关键词： n-dimensional fractional Hardy operator, commutator, C(M)O function, homogeneous Herz space

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Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1. 2, ZHANG Yin-ling1. 2, WANG Fei 1.,2, ZHANG Zhen-hui 3, GUO Yu-xiang1. 2 1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, {1. 2. school of Surveying and land Information Engineering, Henan Polytechnic university, Jiaozuo 454003, {1. 3. Qingdao Branch of Naval Aeronautical Engineering Institute, Qingdao 266041. {1. Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

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Reconstruction of precipitation variation from tree rings in recent 1.00 years in Delingha, Qinghai

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Science china Earth Sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1. HUANG Lei1. LIU Hongbin2, LIANG Eryuan1. FANG Xiuqi3 & WANG Lili1.1. Institute of Geographic Sciences and Natural resources Research, Chinese Academy of Sciences, Beijing 1.01.1. {1. 2. National Climate Center, Beijing 1.0081. {1. 3. Beijing normal university, Beijing 1.0875, {1. Institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China Beijing normal {1. Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1.00 years was re- constructed for Delingha. The reconstruction can capture 63.1. of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1.20—1.33 and 1.33—2001. whereas dry intervals in 1.29—1.1. and 1.34—1.41. In ad- dition, the magnitude in precipitation variation was lower before 1.30 with about 1. mm, but it increased to 30 mm during the period of 1.30 to 1.50. After 1.50, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1.90s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1.00-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21.t century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1.00 years.

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Weighted composition operators between μ-Bloch spaces on the unit ball

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Science china Mathematics 2005年第10期48卷 1349-1368页

作者： ZHANG Xuejun~1.& XIAO Jianbin~2 1. College of Mathematics and Computer Science,Hunan normal {1.,Changsha 41.006,china(email:xuejunttt@263. net) 2. The school of Science,Hangzhou Dianzi {1.,Hangzhou 31.037,china 1. College of Mathematics and Computer Science Hunan Normal University 410006 Changsha China 2. The school of Science Hangzhou Dianzi University 310037 Hangzhou China

In this paper,necessary and sufficient conditions are given for the weighted composition operator T_(ψ,ψ) to be bounded or compact from the space β_μ to β_ν (or β_(μ,0) to β_(ν,0) ) on the unit ball of C^***... 详细信息

关键词： μ-Bloch space, weighted composition operator, boundedness, compactness.

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Checking for normality in linear mixed models

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Science china Mathematics 2012年第4期55卷 787-804页

作者： WU Ping 1.,ZHU LiXing 2,3 & FANG Yun 4 1.school of Finance and Statistics,East {1. normal university,Shanghai 200241.{1. 2 school of Statistics and Mathematics,Yunnan university of Finance and Economics,Yunnan 650221.{1. 3 The Department of Mathematics,Hong Kong Baptist university,Hong Kong 999077,{1. 4 Mathematics and Science College,Shanghai normal university,Shanghai 200234,{1. 1. school of Finance and Statistics East China Normal University Shanghai 200241 China2. School of Statistics and Mathematics Yunnan University of Finance and Economics Yunnan 650221 China3. The Department of Mathematics Hong Kong Baptist University Hong Kong 999077 China4. Mathematics and Science College Shanghai Normal University Shanghai 200234 China

Linear mixed models are popularly used to fit continuous longitudinal data, and the random effects are commonly assumed to have normal distribution. However, this assumption needs to be tested so that further analysis can be proceeded well. In this paper, we consider the Baringhaus-Henze-Epps-Pulley （BHEP） tests, which are based on an empirical characteristic function. Differing from their case, we consider the normality checking for the random effects which are unobservable and the test should be based on their predictors. The test is consistent against global alternatives, and is sensitive to the local alternatives converging to the null at a certain rate arbitrarily close to 1.V~ where n is sample size. ^-hlrthermore, to overcome the problem that the limiting null distribution of the test is not tractable, we suggest a new method： use a conditional Monte Carlo test （CMCT） to approximate the null distribution, and then to simulate p-values. The test is compared with existing methods, the power is examined, and several examples are applied to illustrate the usefulness of our test in the analysis of longitudinal data.

关键词： linear mixed models estimated best linear unbiased predictors BHEP tests conditional MonteCarlo test

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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 Science, Key Laboratory for Water and Sediment Sciences of the Ministry of Education, Beijing normal {1., Beijing 1.0875, china 2 school of Science, Beijing Institute of Education, Beijing 1.001., china 3.school of Mathematical Sciences, Beijing normal {1., Beijing 1.0875, china 4 College of Information Science and Technology, Beijing normal {1., Beijing 1.0875, 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 Technology 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 (1.51.2004) 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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