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Test of magnetic susceptibility and grain-size age models of loess

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Progress in Natural Science:Materials International 2007年第11期17卷 1312-1317页

作者： Chen Yimeng1,2.3, Feng Zhaodong4 and Gong Huili1,2.1. MOE and key Laboratory of Resources Environment and GIS of beijing,{2., china 2. key Laboratory of 3D information Acquisition and application, The Capital Normal University,{2., china 3. Department of Economics & Management of Huizhou University, Huizhou 516007, china 4. key Laboratory of Western china’s Environmental Systems, {12. of education, Lanzhou University, Lanzhou 730000, china) MOE and key Laboratory of Resources Environment and GIS of beijing Beijing 100037 China key Laboratory of 3D information Acquisition and {2. The Capital Normal University Beijing 100037 China Department of Economics & Management of Huizhou University Huizhou 516007 China key Laboratory of Western china’s Environmental Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Ages of the stratigraphic boundary MIS1/2.and MIS3/4 of the Yuanbu loess section in Linxia are used as the basis of the nodal control age. The age of MIS1/2.and MIS3/4 are obtained from the latest international research result—the climatic events recorded in the stalagmite in the Hulu Cave in Nanjing, that MIS1/2.is 11.5 kaB.P. and MIS3/4 is 59.8 kaB.P.. The ages of the two climatic events contain three nodal age control models (Model 1: 0 kaB.P.—59.8 kaB.P.; Model 2. 0 kaB.P.—11.5 kaB.P. and 11.5 kaB.P.—59.8 kaB.P.; Model 3: 11.5 kaB.P.—59.8 kaB.P.), which are used as the nodal control age separately. The deposition times of various stratigraphic horizons are calculated by using the magnetic susceptibility age model and grain-size age model, and then compared with each other. In addition, the AMS14C age, OSL age and the ages of YD and H events are compared with the ages of the corresponding horizons calculated by the three models of nodal control ages. From the analyses of lithologic characters and climatic stages it has been found that both the magnetic susceptibility age model and the grain-size age model have some defects. Because the accurate control ages are selected as the nodal points of the glacial period or interglacial period, the stratigraphic deposition times determined by the high resolution of magnetic susceptibility age model and grain-size age model approximate to the actual ages. As for the relative accuracy of the two age models, the magnetic susceptibility age model is more accurate than the grain-size age model.

关键词： loess nodal control age magnetic susceptibility age model grain-size age model test

Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2. 3, GONG A-du2. 3 1. School of Surveying & Land information Engineering, Henan Polytechnic University, Jiaozuo 454000, china 2. {2. Laboratory of Environmental Change and Natural Disaster, ministry of education, beijing Normal University, beijing 100875, china 3. ministry of Civil Affairs/ministry of education of china Academy of Disaster Reduction and Emergency Management, beijing Normal University, beijing 100875, china [a] School of Surveying & Land information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China [c] ministry of Civil Affairs/ministry of {2. of china Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4, YANG Liqiang1,2.& GAO Bangfei1,2.1. State key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, {2. 100083, china 2. key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of ministry of education, china University of Geo- sciences, {2. 100083, china 3. Faculty of Earth Sciences, china University of Geosciences, Wuhan 430074, china 4. School of Mathematics and {12. Science, Guangzhou University, Guangzhou 510405, china 1. State key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of ministry of {2. China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2. PENG Xiang1,2. TIAN Jindong1, NIU Hanben1, DIAO Luhong3 & LI Hua3 1. key Laboratory of Optoelectronic Devices and Systems of ministry of {2., Institute of Optoelec- tronics, Shenzhen University, Shenzhen 518060, china 2. State key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072.china 3. key Laboratory of Intelligent information Processing, Institute of Computing Technology, Chinese Academy of Sciences, beijing 100080,china 1. key Laboratory of Optoelectronic Devices and Systems of ministry of {2. Institute of Optoelectronics Shenzhen University 518060 Shenzhen China 2. State key Laboratory of Precision Measuring Technology and Instruments Tianjin University 300072 Tianjin China 3. key Laboratory of Intelligent information Processing Institute of Computing Technology Chinese Academy of Sciences 100080 Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.

A study on determining the location of groundwater divide using a mathematical morphology method

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Science china(Technological Sciences) 2006年第z2期49卷 141-148页

作者： PAN Yun, GONG Huili, DUAN Fuzhou & HU Zhuowei key Laboratory of 3D information Acquisition and {2., ministry of education, Capital Normal University, beijing 100037, china key Laboratory of Resource Environment and GIS of beijing, Capital Normal University, beijing 100037, china Capital Normal Univ Minist Educ Key Lab D Informat Acquisit & Applicat 3 Beijing 100037 Peoples R China Capital Normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing Beijing 100037 Peoples R China

Placement of a groundwater divide indicates sink areas and spatial distribution, knowledge of which helps in the mapping of regional aquifer properties and the management of groundwater resources. By applying mathematical morphology to a conceptual model of a watershed and characteristic erosion and dilation operations, this paper proposes a structuring element with which to extract the shape and location of groundwater divide. With due consideration to watershed linearity, a structuring element with three origins is designed to connect watershed points. After erosion, closing, and dilation operations, the groundwater divide is determined; the results indicate this method's feasibility and accuracy.

关键词： groundwater divide, mathematical morphology, structuring element.

Ontology-based analysis of multi-scale modeling of geographical features

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Science china(Technological Sciences) 2006年第z2期49卷 121-131页

作者： WANG Yanhui, LI Xiaojuan & GONG Huili key Laboratory of Three-dimensional {2. Acquisition and application, ministry of education, Capital Normal University, beijing 100037, china beijing key Laboratory of Resource Environment and GIS, Capital Normal University, beijing 100037, china Capital Normal Univ Minist Educ Key Lab Dimens Informat Acquisit & Applicat 3 Beijing 100037 Peoples R China Capital Normal Univ Beijing Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing 100037 Peoples R China

As multi-scale databases based on scale series of map data are built, conceptual models are needed to define proper multi-scale representation formulas and to extract model entities and the relationships among them. However, the results of multi-scale conceptual abstraction schema may differ, according to which cognition, abstraction and application views are utilized, which presents an obvious obstacle to the reuse and sharing of spatial data. To facilitate the design of unified, common and objective abstract schema views for multi-scale spatial databases, this paper proposes an ontology-based analysis method for the multi-scale modeling of geographical features. It includes a three-layer ontology model, which serves as the framework for common multi-scale abstraction schema; an explanation of formulary abstractions accompanied by definitions of entities and their relationships at the same scale, as well as different scales,which are meant to provide strong feasibility, expansibility and speciality functions; and a case in point involving multi-scale representations of road features, to verify the method's feasibility.

关键词： multi-scale representation, ontology-based analysis, multi-scale data modeling, hierarchical ontology.

An Earth multi-body system elasticity and plasticity dynamics model

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Science china(Technological Sciences) 2006年第z2期49卷 23-29页

作者： ZHANG Qingxian, BI Siwen & GONG Huili education ministry {2. Laboratory of Three-dimensional information extraction and application, Capital Normal University, beijing 100037, china State {2. Laboratory of Remote Sensing Science, IRSA, Chinese Academy of Sciences, beijing 100101, china Capital Normal Univ Educ Minist Key Lab Dimens Informat Extract & App Beijing 100037 Peoples R China Chinese Acad Sci IRSA State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China

Research on the elasticity and plasticity dynamics of the Earth multi-body system, including the Earth multi-body system stratum-block's equivalent inertia force system and generalized inertia force, the Earth multi-body system stratum-block's equivalent inertia force system expressed with partial velocity and partial palstance, and Earth multi-body system generalized inertia force expressed with partial velocity and partial palstance. This research provides a theoretical foundation for further investigation of Earth multi-body dynamics.

关键词： Earth multi-body system, equivalent inertia force system, generalized inertia force, elasticity and plasticity, dynamics model.

A numerical study on nonlinear propagation and short-term variability of the migrating diurnal and semidiurnal tides

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Chinese Science Bulletin 2005年第17期50卷 1940-1948页

作者： HUANG Chunming1,2. ZHANG Shaodong1,2.& YI Fan1,2.1. School of Electronic information, Wuhan Universiy, Wuhan 430079, china 2. {2. Laboratory of Geospace Environment and Geodesy, ministry of education, Wuhan University, Wuhan 430079, china School of Electronic information Wuhan University Wuhan 430079 China key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan University Wuhan 430079 China

By using a three-dimensional fully nonlinear numerical model in spherical coordinates and taking the linear steady solutions of the migrating diurnal and semidi-urnal tides in January from the Global-Scale Wave Model (GSWM) as the initial values, we simulate the linear and nonlinear propagations of the migrating diurnal and semidi-urnal tides in the atmosphere from the ground to the lower thermosphere. A comparison of our simulations with the results of GSWM is also presented. The simulation results show that affected by the nonlinearity, the migrating diurnal and semidiurnal tides propagating in the middle and upper atmosphere exhibit evident short-term variability. The nonlinear interactions between the migrating tides and the background atmosphere can obviously alter the background wind and temperature fields, which suggests that the nonlin-ear propagations of the migrating diurnal and semidiurnal tides impact significantly on the transient dynamical and thermal structures of the background middle and upper at-mosphere and the nonlinear effect is an important cause of the difference between the results of GSWM and observa-tions.

关键词：大气非线性传播数学模型可变性温度场

Reverse reconciliation for continuous variable quantum key distribution

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Science china(Physics,Mechanics & Astronomy) 2010年第1期53卷 100-105页

作者： LU ZhiXin 1,2., YU Li 1,2., LI Kang 1,2., LIU BingCan 1,2.3 , LIN JianGui 1,2., JIAO RongZhen 1,2.& YANG BoJun 1,2. School of Science, beijing University of Posts and Telecommunications, beijing 100876,{2. 2.key Laboratory of information Photonics and Optical Communication, ministry of education, beijing University of Posts and Telecommunications, beijing 100876,{2. 3 Department of Fundamental Courses, Academy of Armored Force Engineering, beijing 100072.{2. 1. School of Science Beijing University of Posts and Telecommunications Beijing 100876 China2. Key Laboratory of Information Photonics and Optical Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China3. Department of Fundamental Courses Academy of Armored Force Engineering Beijing 100072 China

An efficient and practical post-processing technique based on reverse reconciliation for continuous variable quantum key distribution is proposed and simulated with low-density parity check (LDPC) codes. MultiLevel Coding/ MultiStage Decoding, which fully utilizes optimization technique such as vector quantization and iterative decoding and the optimal channel coding most close to the Shannon limit, was used to realize efficient reverse reconciliation algorithm. Simulation results showed that the proposed method can improve the secure key distribution rate to 2.2.kb/s and the coding efficiency to 0.89 over 2. km in single-mode optical fiber. Moreover, there still is room for much improvement.

关键词： quantum communication key distribution reverses reconciliation low-density parity check codes