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wuhan university Journal of Natural Sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2.3 , XU Bao-wen 2.3,4., ZHOU Xiao-yu 2.3,4.1. Department of Computer Science and Engineering, Nanjing university of Posts and Telecommunications, Nanjing 2.0003, Jiangsu, china 2. Department of Computer Science and Engineering, Southeast university, Nanjing 2.0096, Jiangsu, china 3. Jiangsu Institute of Software Quality, Nanjing 2.0096 Jiangsu, china 4. The state key Laboratory of Software Engineering, {14., wuhan 4.0072. Hubei, china Department of Computer Science and Engineering Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Department of Computer Science and Engineering Southeast University Najing Jiangsu China Jiangsu Institute of Software Quality Nanjing Jiangsu China The state key Laboratory of Software Engineering Wuhan University Wuhan Hubei China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. key words WWW - search engine - query reconstruction - feedback CLC number TP 311. 135.4.Foundation item: Supported by the National Natural Science Fundation of {4. (60373066). National Grand Fundamental Research 973 Program of {4. (2.02.B312.0). Opening Foundation of state key Laboratory of Software Engineering in wuhan university, Opening Foundation of Jiangsu key Laboratory of Computer information Processing Technology in Soochow {14.Biography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

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Numerical study of the auroral particle transport in the polar upper atmosphere

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Science china(Technological Sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2. MA ShuYing1,2.& PU ZuYin3 1 School of Electronic information, wuhan university, {2., china 2.key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, {2., china 3 School of Earth and Space Sciences, Peking university, Beijing 100871, china School of Electronic information Wuhan University Wuhan China key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan China School of Earth and Space Sciences Peking University Beijing China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2., to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2.ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

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Evolutionary ciphers against differential power analysis and differential fault analysis

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Science china(information Sciences) 2012年第11期55卷 2555-2569页

作者： TANG Ming1,2.QIU ZhenLong2.YANG Min3,CHENG PingPan2.GAO Si2.LIU ShuBo1,2.& MENG QinShu2.1state key Lab.of AIS & TC,Ministry of Education,{2.,wuhan 4.0072.china 2.chool of Computers,{2.,wuhan 4.0072.china 3International School of Software,{2.,wuhan 4.0072.china state key Lab. of AIS & TC Ministry of Education Wuhan University Wuhan China School of Computers Wuhan University Wuhan China International School of Software Wuhan University Wuhan China

Side channel analysis(SCA) focuses on attacking cryptographic algorithm implementations by collecting leaked information and analyzing the correlation between the leaked and key information in the cryptographic ***,SCA is the main threat to cryptographic implementations,with DPA(differential power analysis) and DFA(differential fault analysis) being two of the most threatening types of ***,the existing countermeasures against DPA and DFA have shortcomings and can hardly protect cipher designs *** on a comprehensive analysis of DPA and DFA,this paper proposes a new idea of using an evolutionary cipher(EVOC) against DPAs based on the model proposed by Kocher,and several different new types of *** fact,an EVOC is a kind of dynamic cipher designing ***,combined with intelligent searching algorithms and cryptography design policies,EVOCs utilize the dynamic and unpredictable properties of TRNG(a truly random number generator) to ensure cipher design at a high level of ***,with an EVOC we could design cryptography algorithms with high security to resist mathematical analysis as well as DPAs and *** paper analyzes and proves the security,efficiency,cost,and original features of EVOCs against DPA and DFA both theoretically and *** with existing countermeasures against SCAs,EVOCs use dynamic non-linear operations to destroy the bases of DPA and *** the algorithm level,EVOCs are more efficient than other resistance *** on the theory and experiments,this paper proposes certain modifications to the EVOC in the AES(advanced encryption standard) algorithm,which can be referenced by other dynamic designs of cryptographic algorithms.

关键词： evolutionary cipher DPA countermeasure DPA DFA countermeasure DFA SCA

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Mining subsidence control by solid backfilling under buildings

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中国有色金属学会会刊：英文版 2011年第S3期21卷 670-674页

作者： ZHA Jian-feng1, 2. 3, GUO Guang-li1, 2. FENG Wen-kai3, WANG Qiang1, 2.1. key Laboratory for Land Environment and Disaster Monitoring of the {4. Bureau of {2. and mapping, china university of Mining and Technology, Xuzhou 2.1116, china 2. Jiangsu key Laboratory of Resources and Environmental information Engineering, china university of Mining and Technology, Xuzhou 2.1116, china 3. {4. key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of Technology, Chengdu 610059, china key Laboratory for Land Environment and Disaster Monitoring of the state Bureau of {2. and mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu key Laboratory of Resources and Environmental information Engineering China University of Mining and Technology Xuzhou 221116 China state key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining can reduce the buildings' damage caused by mining greatly. The reduction of subsidence value, the slow advancing speed and the subsidence caused by backfilling body compaction are the main reasons that solid backfilling mining velocity decreases significantly. Based on the research of mechanism, some principles on subsidence control of solid backfilling mining under buildings were proposed. The equivalent mining height was designed according to the fortification criteria of buildings and their attachment structures, which enables the ground movement and deformation caused by mining to be less than the corresponding fortification criteria.

关键词： solid backfilling mining subsidence control mining under buildings

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Petrogenesis of Indosinian volcanic rocks in Songpan-Garze fold belt of the northeastern Tibetan Plateau:New evidence for lithospheric delamination

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Science china Earth Sciences 2010年第9期53卷 1316-1328页

作者： CAI HongMing1,2. ZHANG HongFei1,2. XU WangChun1,2. SHI ZhangLiang1,2.& YUAN HongLin3 1 {4. key Laboratory of Geological Processes and Mineral Resources, {2. 4.0074. china 2.Faculty of Earth Sciences, china university of Geosciences, {2. 4.0074. china 3 {4. key Laboratory of Continental Dynamics, Northwest university, Xi’an 710069, china state key Laboratory of Geological Processes and Mineral Resources Wuhan China Faculty of Earth Sciences China University of Geosciences Wuhan China state key Laboratory of Continental Dynamics Northwest University Xi’an China

In the Songpan-Garze fold belt of the northeastern Tibetan Plateau, an Indosinian lithospheric delamination model has been proposed, based on previous investigation of widespread granitoids. However, this model lacks comparable information from volcanism in the area. During the Indosinian delamination in the Songpan-Garze fold belt, whether partial melting of litho- spheric mantle taken place is debated. This paper reports U-Pb zircon LA-ICP-MS ages, geochemical and Sr-Nd-Hf isotopic compositions from the Aba and Wasai calc-alkaline volcanic rocks in the central Songpan-Garze fold belt. Obtained magma crystallization ages are 2.0±3 Ma for the Aba andesite and 2.5±1 Ma for the Wasai andesite. These are consistent with magma crystallization ages of the late Indosinian granitoids in the Songpan-Garze fold belt that formed in a post-collisional tectonic setting. The Aba and Wasai andesites have distinct geochemical singnatures. The former has higher Al2.3, K2., Rb but lower Na2., Ba and Sr contents, suggesting differences in their magmatic evolution. The Aba andesites have ISr values of 0.7070-0.7076 and εNd(t) values of -3.9 to -5.3, and the Wasai andesites have ISr values of 0.7075-0.7077 and εNd(t) values of -3.6 to -3.9. Zircons show εHf(t) values of -3.7 to 0.3 for the Aba andesites and -2.7 to 5.5 for the Wasai andesites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that fractional crystallization and crustal assimilation processes are not key roles for their magma evolution, implying that their chemical compositions are those of primary melts. We suggest that the magma of the Aba andesites originated predominantly from a crustal source, with a minor mantle-derived component. The source region of the magma was likely at the crust-mantle boundary. The magma of the Wasai andesites resulted from partial melting of lithospheric mantle, which was probably metasomatized by fluids so that it was amphibole bearing. The petrogenesis of the Aba and Wasai andesite

关键词： volcanism U-Pb dating geochemistry petrogenesis lithospheric delamination Songpan-Garze fold belt

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Dependence Analysis Based on Dynamic Slicing for Debugging

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wuhan university Journal of Natural Sciences 2001年第Z1期6卷 398-404页

作者： Chen Zhen qiang 1, Xu Bao wen 1,2.1 Department of Computer Science & Engineering, Southeast university, Nanjing 2.0096, china {2. key Laboratory of Software Engineering, wuhan university, wuhan 4.0072. china Department of Computer Science & Engineering Southeast University Nanjing China state key Laboratory of Software Engineering Wuhan University Wuhan China

Dynamic program slicing is an effective technique for narrowing the errors to the relevant parts of a program when debugging. Given a slicing criterion, the dynamic slice contains only those statements that actually affect the variables in the slicing criterion. This paper proposes a dynamic slicing method based on static dependence analysis. It uses the program dependence graph and other static information to reduce the information needed to be traced during program execution. Thus, the efficiency is dramatically improved while the precision is not depressed. The slicing criterion is modified to fit for debugging. It consists of file name and the line number at which the statement is.

关键词： program slice slicing criterion program dependence graph

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Development of environmental monitoring satellite systems in china

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Science china Earth Sciences 2010年第S1期53卷 1-7页

作者： LI GuoPing1 & CAO ChunXiang2.1 School of Earth and Space Sciences,Peking university,Beijing 100871,china {2. {4. Laboratory of remote sensing Science,Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of Sciences and Beijing Normal university,Beijing 100101,china School of Earth and Space Sciences Peking University Beijing China state key Laboratory of {2. sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China

With the increase in global environmental problems,the necessity and urgency of remote sensing technology being applied to environmental monitoring has been widely recognized around the *** has launched the environment and disaster monitoring and forecasting small satellite constellation HJ-1A/B and the FY3 atmosphere and environmental satellite,but they still cannot fully satisfy requirements for environmental *** paper summarizes the current status of satellite environmental monitoring in {2. and the existing problems of inadequate load design and low data utilization efficiency,and discusses the demand for environmental monitoring *** on the development of foreign satellite systems for environmental monitoring,the future development and key tasks of the environmental monitoring satellite system in {2. is discussed,as are some related initiatives.

关键词： environmental satellite environmental monitoring global climate change specialty load satellite system

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Analysis of forest backscattering characteristics based on polarization coherence tomography

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Science china(Technological Sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,LI XiaoWen 1,2.CHEN ErXue 3,CHENG Jian 4.& CAO ChunXiang 2. Institute of Geo-Spatial information Science and Technology,university of Electronic Science and Technology of {2.,Chengdu 610054.{2. 2.state key Laboratory of remote sensing Science,Jointly Sponsored by the Institute of remote sensing Applications of Chinese Academy of Sciences and Beijing Normal university,Beijing 100101,{2. 3Institute of Forest Resources information Technique of Chinese Academy of Forestry,Beijing 100091,{2. 4.School of Electronic Engineering,university of Electronic Science and Technology of {2.,Chengdu 610054.{2. Institute of Geo-Spatial information Science and Technology University of Electronic Science and Technology of China Chengdu China state key Laboratory of {2. sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Institute of Forest Resources information Technique of Chinese Academy of Forestry Beijing China School of Electronic Engineering University of Electronic Science and Technology of China Chengdu China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2.D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POLInSAR PCT vertical structure function

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Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science china(Technological Sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN XiaoLing 1,2.3,YU ZhiFeng 1,XIAO JingJing 1,QIU Feng 1 & ZHAO Xi 1 1 state key Laboratory of {2. Engineering in {4.,mapping and remote sensing,wuhan university,wuhan 4.0079,china 2.1} Laboratory of Poyang Lake Wetland and Watershed Research,Ministry of Education,Jiangxi Normal university,Nanchang 33002.,china 3 The key Laboratory of Poyang Lake Environment and Resource Utilization,Ministry of Education,Nanchang university,Nanchang 330031,china state key Laboratory of {2. Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China key Laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal University Nanchang China The key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education Nanchang University Nanchang China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote {2. study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

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Retrieving crop leaf area index by assimilation of MODIS data into a crop growth model

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Science china Earth Sciences 2010年第5期53卷 721-730页

作者： WANG DongWei1,2.3, WANG JinDi1,2.& LIANG ShunLin4.1 state key Laboratory of {2. sensing Science, Jointly Sponsored by Beijing Normal university and Institute of {2. sensing Applications, CAS, Beijing 100875, china 2.School of Geography, Beijing key Laboratory of Environmental {2. sensing and Digital City, Beijing Normal university, Beijing 100875, china 3 Haihe River Water Conservancy Commission, Tianjin 300170, china 4.Department of Geography, university of Maryland, College Park, MD 2.74.0} USA state key Laboratory of {2. sensing Science Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing Applications CAS Beijing China School of Geography Beijing Key Laboratory of Environmental Remote Sensing and Digital City Beijing Normal University Beijing China Haihe River Water Conservancy Commission Tianjin China Department of Geography University of Maryland College Park USA

Leaf area index (LAI) is an important parameter in monitoring crop growth. One of the methods for retrieving LAI from remotely sensed observations is through inversion of canopy reflectance models. Many model inversion methods fail to account for variable LAI values at different crop growth stages. In this research, we use the crop growth model to describe the LAI changes with crop growth, and consider a priori LAI values at different crop growth stages as constraint information. The {2. approach of this research is to assimilate multiple canopy reflectance values observed at different growth stages and a priori LAI values into a coupled crop growth and radiative transfer model sequentially using a variational data assimilation algorithm. Adjoint method is used to minimize the cost function. Any other information source can be easily incorporated into the inversion cost function. The validation results show that the time series of MODIS canopy reflectance can greatly reduce the uncertainty of the inverted LAI values. Compared with MODIS LAI product at Changping and Shunyi Counties of Beijing, this method has significantly improved the estimated LAI temporal profile.

关键词： inversion leaf area index crop growth model time series MODIS

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