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Optimization of mathematical models for thematic maps

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Science china(Technological Sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1.ZHANG An1.JIANG LiLi1.ZOU Xiuping2,XU Li3 & CHENG Xi1.4 1.institute of Geographical Sciences and Natural resources {1.,chinese academy of Sciences,beijing 1.01.1.china 2 institute of policy and Management,chinese academy of Sciences,beijing 1.0080,china 3 Taishan University,Taian 271.21.china 4 Graduate University of chinese academy of Sciences,beijing 1.0049,china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical {1. goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

potential land for plantation of Jatropha curcas as feedstocks for biodiesel in china

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Science china Earth Sciences 2010年第1期53卷 120-127页

作者： WU WeiGuang 1.2,3,HUANG JiKun 1.3 & DENG XiangZheng 1.3 1.institute of Geographic Sciences and Natural resources {1.,chinese academy of Sciences,beijing 1.01.1.china 2 Department of Economics and Management,Zhejiang Forestry University,Linan 31.300,china 3 Center for chinese Agricultural policy,chinese academy of Sciences,beijing 1.01.1.china 1. institute of Geographic Sciences and Natural resources {1. Chinese Academy of Sciences Beijing 100101 China2. Department of Economics and Management Zhejiang Forestry University Linan 311300 China3. Center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China

As a renewable energy,biofuel has attracted great attention in china and the rest of *** with the national food security,china recently has shifted its biofuel development priority from grain-based to non-grain-based biofuels,including forest-based biodiesel,since *** curcas is one of major biodiesel ***,there is rising debate on availability of land for expanding Jatropha curcas *** overall goal of this paper is to evaluate potential land for Jatropha curcas used as feedstock for biodiesel in *** on remote sensing data on land use,data on meteorological,soil and land slope,and suitable environment for Jatropha curcas plantation,this study uses Agro Ecological Zone method and considers social-economic constraints to evaluate potential suitable land for Jatropha curcas plantation in china's major Jatropha curcas production region,Southwest *** results show that while there are some potential lands to expand Jatropha curcas areas,amount of these lands will hardly meet the government's target for Jatropha curcas-based biodiesels development in the *** may need to reconsider its long-term targets on the development of Jatropha curcas-based biodiesels.

关键词： biodiesel Jatropha curcas potential land suitability evaluation Southwest china

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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Science china Technological Sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1.2,3, WAN WeiXing1. liu LiBo1. {1. BaiQi1. ZHAO BiQiang1.& ZHANG ManLian1.1.institute of Geology and Geophysics, chinese academy of Sciences, beijing 1.0029, china 2 Wuhan institute of physics and Mathematics, chinese academy of Sciences, Wuhan 430071. china 3 Graduate University, chinese academy of Sciences, beijing 1.0049, china 1. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. Wuhan institute of physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China 3. chinese {1. of Sciences Graduate University Beijing 100049 China

The TIME-IGGCAS (Theoretical Ionospheric Model of the Earth in institute of Ge- ology and Geophysics, {1. academy of Sciences) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IrI, NeQuick-ITUr, and TItheridge temperature models) and multi-observations (GpS, Ionosondes, Topex, DMSp, FOrMOSAT, and CHAMp) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

regional differences and determinants of built-up area expansion in china

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Science china Earth Sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1.2,ZHU LiFen3,1.& DENG XiangZheng1.2 1.Center for chinese Agricultural {1.,chinese academy of Sciences,beijing 1.01.1.china 2 institute of Geographic Sciences and Natural resources research,chinese academy of Sciences,beijing 1.01.1.china 3 research Center of the Economy of the Upper reaches of the Yangtze river,Chongqing Technology and Business University,Chongqing 400067,china 1. Center for chinese Agricultural {1. Chinese Academy of Sciences Beijing 100101 China 2. institute of Geographic Sciences and Natural resources {1. Chinese Academy of Sciences Beijing 100101 China 3. research Center of the Economy of the Upper reaches of the Yangtze river Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the chinese {1. of Sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in china from the late 1.80s to 2000,and empirically estimates the major determinants of BUA expansion in different regions in 1.96―*** 1.89―2000,although china's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric analysis reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, china

parallel Implementation of the CCSDS Turbo Decoder on GpU

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china Communications 2024年第10期21卷 70-77页

作者： liu Zhanxian liu rongke Zhang Haijun Wang ning Sun Lei Wang Jianquan School of Computer&Communication Engineering University of Science and Technology BeijingBeijing 100083China School of Electronic and information Engineering Beihang UniversityBeijing 100191China beijing Engineering and Technology {1. Center for Convergence Networks and Ubiquitous Services Institute of Artificial IntelligenceUniversity of Science and Technology BeijingBeijing 100083China School of information Engineering Zhengzhou UniversityZhengzhou 450001China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China

This paper presents a software turbo decoder on graphics processing units(GpU).Unlike previous works,the proposed decoding architecture for turbo codes mainly focuses on the Consultative Committee for Space Data Systems(CCSDS)***,the information frame lengths of the CCSDS turbo codes are not suitable for flexible sub-frame parallelism *** mitigate this issue,we propose a padding method that inserts several bits before the information frame *** obtain low-latency performance and high resource utilization,two-level intra-frame parallelisms and an efficient data structure are *** presented Max-Log-Map decoder can be adopted to decode the Long Term Evolution(LTE)turbo codes with only small *** proposed CCSDS turbo decoder at 1. iterations on NVIDIA rTX3070 achieves about 1.0 Mbps and 50Mbps throughputs for the code rates 1.6 and 1.2,respectively.

关键词： CCSDS CUDA GpU parallel decoding turbo codes

Current Status and prospects of Biomass Energy Industry in china

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chinese Forestry Science and Technology 2009年第1期8卷 47-52页

作者： liu {1. research institute of Forestry policy and information,chinese academy of Forestry,beijing 1.0091,p.r.china

At present biomass energy industry is in its infancy in china and it has a bright future. Biomass energy production used grain as raw materials has entered industrialization *** key technologies of biomass energy industry are coming to *** has issued relevant industrial standards laws and regulations,and has provided support in finance,loan,tax,*** china's biomass energy industry is faced with many problems which need to be *** example,taking grain as raw materials is unsustain...

关键词： biomass energy industry status evaluation major problems prospects

Significant enhancement in local thermal conductivity of erythritol at interface with nanoparticles due to their interaction

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Nano research 2024年第8期17卷 7726-7736页

作者： ning Cao Yanhui Feng Kening Yan Zihan liu Jiawei Wan Lin Qiu School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

When nano-fillers are used to enhance the thermal conductivity of organic phase change materials(pCMs),the naturally formed interface is considered to hinder thermal transport of the composite ***,the effect of the interface on the thermal properties of surrounding pCM has not been fully *** this paper,three composite pCMs(Ery@SiC,Ery@SiO_(2) and Ery@Si_(3)N_(4))were prepared by melt-blending *** local thermal conductivity and reduced Young’s modulus(E^(*))of the erythritol at the interface and far away from the interface in the composite pCMs were simultaneously measured by scanning thermal microscopy(SThM).The results revealed significant enhancement in local thermal conductivity of erythritol at the interface and its obvious positive correlation with E^(*).For different composite pCMs,molecular dynamics(MD)simulations suggested that the increase in intrinsic thermal conductivity and E^(*)of erythritol is attributed to the increase in interaction energy between erythritol and nanoparticles,as more erythritol phonon vibrations transform from localized mode to delocalized mode and erythritol has a higher density at the *** findings will provide new ideas for the design of pCM for energy storage.

关键词： scanning thermal microscopy phase change materials thermal conductivity reduced Young’s modulus interaction energy phonon participation ratio

Impacts of the Wenchuan Earthquake on the Giant panda Nature reserves in china

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Journal of Mountain Science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng institute of Geographic Sciences and Natural resources {1. Chinese Academy of Sciences Beijing 100101 China Center for chinese Agricultural {1. Chinese Academy of Sciences Beijing 100101 China Graduate University of the chinese{1. of Sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake remote sensing Giant panda Giant panda nature reserve rapid assessment method

A novel logic-based automatic approach to constructing compliant security policies

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Science china({1. Sciences) 2012年第1期55卷 149-164页

作者： BAO YiBao1.2,4,YIN LiHua1.FANG BinXing 1.3&GUO Li 1.1.0} of Computing Technology,{1. academy of Sciences,beijing 1.01.0,china 2institute of Electronic Technology,information Engineering University,Zhengzhou 450004,china 3beijing University of posts and Telecommunications,beijing 1.01.0,china 4Graduate University,the {1. academy of Science,beijing 1.0049,china 1. institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China2. Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China4. Graduate University the Chinese Academy of Science Beijing 100049 China3. Beijing University of Posts and Telecommunications Beijing 100190 China

It is significant to automatically detect and resolve the incompliance in security *** existing works in this field focus on compliance verification,and few of them provide approaches to automatically correct the incompliant security *** paper proposes a novel approach to automatically transform a given security policy into a compliant *** security policy Π and delegation policy M declared by logic programs,the approach automatically rewrites Π into a new one ΠM which is compliant with M and is readable by the *** prove that the algorithm is sound and complete under noninterference ***,we show that the security policy query evaluation algorithm with conflict and unsettlement resolution still works very well on Π*** approach is automatic,so it doesn't require a administrator with excess *** this sense,our proposal can help us to save much manpower resource in security management and improves the security assurance abilities.

关键词： security policy rewriting logic program compliance