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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

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 Key {2. of Three-dimensional information extraction and application, Capital Normal University, beijing 100037, china State Key {2. 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.

dimension reduction based on weighted variance estimate

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Science china Mathematics 2009年第3期52卷 539-560页

作者： ZHAO JunLong1 & XU XingZhong2.1 Department of Mathematics, Beihang University laboratory of Mathematics, information and Behavior of the {2. of education, beijing 100083, china 2.Department of Mathematics, beijing Institute of Technology, beijing 100081, china Department of Mathematics Beihang University laboratory of Mathematics Information and Behavior of the Ministry of Education Beijing 100083 China Department of Mathematics Beijing Institute of Technology Beijing 100081 China

In this paper, we propose a new estimate for dimension reduction, called the weighted variance estimate (WVE), which includes Sliced Average Variance Estimate (SAVE) as a special case. Bootstrap method is used to select the best estimate from the WVE and to estimate the structure dimension. And this selected best estimate usually performs better than the existing methods such as Sliced Inverse Regression (SIR), SAVE, etc. Many methods such as SIR, SAVE, etc. usually put the same weight on each observation to estimate central subspace (CS). By introducing a weight function, WVE puts different weights on different observations according to distance of observations from CS. The weight function makes WVE have very good performance in general and complicated situations, for example, the distribution of regressor deviating severely from elliptical distribution which is the base of many methods, such as SIR, etc. And compared with many existing methods, WVE is insensitive to the distribution of the regressor. The consistency of the WVE is established. Simulations to compare the performances of WVE with other existing methods confirm the advantage of WVE.

关键词： central subspace contour regression sliced average variance estimate sliced inverse regression sufficient dimension reduction weight function 62.08 62.05

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 {2., beijing Normal University, beijing 100875, china 2.School of Science, beijing Institute of {2., 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 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 (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

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,{2. 2. School of Surveying and land information Engineering, Henan Polytechnic University, Jiaozuo 454003,{2. 3. Qingdao Branch of Naval Aeronautical Engineering Institute, Qingdao 2.6041,{2. 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

Timeliness evaluation of task-oriented networked space-based information system

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Journal of Systems Engineering and Electronics 2011年第4期22卷 621-627页

作者： Chen Chen 1,2.and Jie Chen 2.3 1.Department of Automation,Tsinghua University,beijing 100084,P.R.china 2.School of Automation,beijing Institute of Technology,beijing 100081,P.R.china 3.Complex System Intelligent Control and Decision,ministry of education,beijing 100081,P.R.china Department of Automation Tsinghua University Beijing 100084 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China School of Automation Beijing Institute of Technology Beijing 100081 P. R. China Complex System Intelligent Control and Decision Ministry of Education Beijing 100081 P. R. China

Task-oriented networked information system is an integrated information system which builds on multi-satellite networking to accomplish one or more tasks. In the background of emer- gency relief for {2.s, system working flow and response process are analyzed, and a timeliness effectiveness evaluation index system is constructed at multi-task level. The effectiveness is a measurement of promptness of information return. In evalua- tion process, system performance and tasks are associated, then an evaluation model based on efficacy function is established, and different evaluation criteria are selected for different tasks. A distributed simulation system is constructed, and the execution of task is decomposed. The simulation platform provides a comprehensive data source for evaluation. The results are easy to compare with each other, which reflects system time efficiency in different satellites networks and provides actual systems with basis and reference for design and {2..

关键词： timeliness efficacy function space-based informationsystem simulation system.