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Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 College of Geographical science, chongqing Normal {2., chongqing 400047, china 2.College of Resources and Environmental science, chongqing {2., chongqing 400044, china 3 College of Resources science & Technology, Beijing Normal {2., Beijing 100875, china College of Geographical science Chongqing Normal University Chongqing 400047 China College of Resources and Environmental science Chongqing University Chongqing 400044 China College of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Influence of stacking fault energy on formation of long period stacking ordered structures in Mg-Zn-Y-Zr alloys

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Progress in Natural science:Materials International 2011年第6期21卷 485-490页

作者： Fu-sheng PAN~(1,2.,Su-qin LUO~1,Ai-tao TANG~(1,2.,Jian PENG~(1,2.,Yun LU~3 1.College of Materials science and engineering,{2. university,{2. 400044,china 2.National engineering Research Center for Magnesium Alloys,{2. university,{2. 400044,china 3.Faculty of engineering,Chiba university,Chiba 2.3-852.,Japan [a] College of Materials science and engineering Chongqing University Chongqing 400044 China [b] National engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China [c] Faculty of engineering Chiba University Chiba 263-8522 Japan

The influence of alloying elements on the stacking fault energy（SFE） of Mg-Y-Zn-Zr alloys was calculated by using first-principles,and the microstructure of as-cast Mg-1.05Y-0.79Zn-0.07Zr（mole fraction,%） alloy prepared by conventional casting was investigated by SEM,TEM and *** block-like long period stacking ordered（LPSO） phase,the lamellar LPSO phase and stacking faults were observed simultaneously and the lamellar LPSO structure and stacking faults were both formed on （0001）α-Mghabit plane and grown or extended along[01 1 0]α-*** calculation results by the first-principles showed that the addition of Y can sharply decrease the stacking fault energy of the Mg-Zn-Y-Zr alloy,while Zn slightly increases the stacking fault energy of the *** influence of stacking fault energy on the formation of LPSO was *** shows that LPSO may nucleate directly through stacking faults and the lower stacking fault energy was in favor of formation of LPSO.

关键词： magnesium alloy Mg-Zn-Y-Zr long period stacking ordered(LPSO) structures stacking fault energy(SFE) firstprinciples calculation

Effects of rapid solidification on the microstructure and microhardness of a lead-free Sn-3.5Ag solder

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Rare Metals 2006年第4期25卷 365-370页

作者： SHEN Jun LIU Yongchang Han Yajing GAO Houxiu College of mechanical engineering Chongqing University Chongqing 400044 China College of Materials science and engineering Tianjin University Tianjin 300072 China

A lead-free Sn-3.5Ag solder was prepared by rapid solidification technology. The high solidification rate, obtained by rapid cooling, promotes nucleation, and suppresses the growth of Ag3Sn intermetallic compounds （IMCs） in Ag-rich zone, yielding fine Ag3Sn nanoparticulates with spherical morphology in the matrix of the solder. The large amount of tough homogeneously-dispersed IMCs helps to improve the surface area per unit volume and obstructs the dislocation lines passing through the solder, which fits with the dispersion-strengthening theory. Hence, the rapidly-solidified Sn-3.5Ag solder exhibits a higher rnicrohardness when compared with a slowly-solidified Sn-3.5Ag solder.

关键词： lead-free solder nanoparticulate rapid solidification intermetallic compounds dispersion-strengthening effect

Construction and cross-correlation analysis of the affective physiological response database

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science china(Information sciences) 2010年第9期53卷 1774-1784页

作者： WEN WanHui1,QIU YuHui2.LIU GuangYuan1*,CHENG NanPu3 & HUANG XiTing4 1school of Electronic and Information engineering,Southwest {2.,chongqing 400715,china 2.ollege of Computer and Information science,Southwest {2.,chongqing 400715,china 3school of Materials science and engineering,Southwest {2.,chongqing 400715,china 4school of Psychology,Southwest {2.,chongqing 400715,china 1. school of Electronic and Information engineering Southwest University Chongqing 400715 China2. College of Computer and Information Science Southwest University Chongqing 400715 China3. School of Materials Science and Engineering Southwest University Chongqing 400715 China4. School of Psychology Southwest University Chongqing 400715 China

Six kinds of emotions,namely joy,surprise,disgust,grief,anger and fear,are elicited from 300 ordinary college students by means of high-rated movie *** signals of galvanic skin response(GSR),heart rate(HR),blood volume pulse(BVP),electrocardiogram(ECG),respiration(Rsp.),facial electromyography(EMG) and two channels of electroencephalography(EEG) from the frontal lobe were recorded while the subjects were watching the affective eliciting *** samples of each kind of signals are analyzed by using random matrix theory(RMT).From the distribution of the eigenvalues and eigenvectors of the correlation matrices of BVP,facial EMG and two EEGs,we find that the statistical properties of these four kinds of signals coincide with the RMT ***,the largest eigenvalue and the corresponding eigenvector component distribution of the correlation matrices of GSR,HR,ECG and *** deviated significantly from the RMT *** experiments also reveal that the correlations between two arbitrary samples of BVP,facial EMG or EEGs does not result from affective response but from random noises,whereas the amplitude variations of GSR,HR,ECG and *** the correlated affective physiological response *** to the data analysis results of RMT,110 features are firstly extracted from the GSR and HR signals,and then a subset of the initial features is selected by using the Backward Selection *** affective data samples each of which is a vector of the features are classified by using a Fisher classifier,and furthermore,the user-independent emotion recognition systems with good prediction performance are constructed during the model selection process.

关键词： affective computing emotion recognition affective physiological response database correlation analysis random matrix theory

Study on An Absolute Non-Collision Hash and Jumping Table IP Classification Algorithms

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Wuhan university Journal of Natural sciences 2004年第5期9卷 835-838页

作者： SHANG Feng-jun 1,2.,PAN Ying-jun 1 1. Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic engineering,chongqing {2., chongqing 400044,china 2. College of Computer science and Technology, chongqing {2. of Posts and Telecommunications, chongqing 400065,china chongqing university Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic Engineering Chongqing China (GRID:grid.190737.b) (ISNI:***) chongqing university of Posts and Telecommunications College of Computer Science and Technology Chongqing China (GRID:grid.411587.e) (ISNI:***) chongqing university Key Laboratory of Opto-Electronic Technology and System of Ministry of Education/College of Opto-Electronic Engineering Chongqing China (GRID:grid.190737.b) (ISNI:***)

In order to classify packet, we propose a novel IP classification based the non-collision hash and jumping table trie-tree (NHJTTT) algorithm, which is based on noncollision hash Trie-tree and Lakshman and Stiliadis proposing a 2.dimensional classification algorithm (LS algorithm). The core of algorithm consists of two parts: structure the non-collision hash function, which is constructed mainly based on destination/source port and protocol type field so that the hash function can avoid space explosion problem; introduce jumping table Trie-tree based LS algorithm in order to reduce time complexity. The test results show that the classification rate of NHJTTT algorithm is up to 1 million packets per second and the maximum memory consumed is 9 MB for 10 000 rules. Key words IP classification - lookup algorithm - trie-tree - non-collision hash - jumping table CLC number TN 393.06 Foundation item: Supported by the chongqing of Posts and Telecommunications Younger Teacher Fundation (A2.03-03).Biography: SHANG Feng-jun (1972.), male, Ph.D. candidate, lecture, research direction: the smart instrument and network.

关键词： IP classification lookup algorithm trie-tree non-collision hash jumping table

Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

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science china Chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2. LIU ZhongFang1 & LIU ShaoPu1 1 school of Chemistry and Chemical engineering, Southwest {2., chongqing 400715, china 2.Department of Chemistry, Fuling Normal {2., chongqing 408000, china school of Chemistry and Chemical engineering Southwest UniversityChongqing400715China Department of Chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1, Feng Jiuchao1,2. Xie Shengli2.and Wang Shiyuan1(1. Faculty of Electronic and Information engineering ,Southwest university, {2. 400715, china 2. school of Electronic and Information engineering, South china university of Technology, Guangzhou 510641, china) Faculty of Electronic and Information engineering Southwest University Chongqing 400715 China school of Electronic and Information engineering South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

Water-Air Mixing Jet Produced by Electro-hydraulic Impulse Technology Strengthening the Quality of Surface of Metal Materials

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Journal of Materials science & Technology 2002年第3期18卷 194-196页

作者： Zhenfang LIAO and Shijin ZHANGCollege of mechanical engineering, {2. university, {2. 400044, china [ Manuscript received September 10, 2.01, in revised form October 2., 2.01] chongqing Univ Coll Mech Engn Chongqing 400044 Peoples R China

Electro-hydraulic impulse water-air mixing jet by which the quality of metal materials can be improved is described in this paper. The experimental results proved that the hardness and the micro-hardness of the surface layer of metal materials can be improved with this method, for example, the microhardness of CrWMn can be increased by 35.62.percent.

关键词： Electro-hydraulic impulse Water-air mixing jet Quality of surface

Flow instability of buoyant-Marangoni convection in the LEC GaAs melt

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science china(Technological sciences) 2008年第4期51卷 397-406页

作者： CHEN ShuXian1 & LI MingWei2.3 1 Aviation engineering Institute, Civil Aviation Flight university of{2., Guanghan 618307,{2. 2.Institute of Power engineering of chongqing university, chongqing 400030,{2. 3 Research Center of Biological Function Information and Instruments of chongqing university by Sec-ond-Term National 985 Project, chongqing university, chongqing 400030,{2. Aviation engineering Institute Civil Aviation Flight University of China Guanghan 618307 China Institute of Power engineering of chongqing {2. Chongqing 400030 China Research Center of Biological Function Information Instruments of chongqing university by Second-Term National 985 Project Chongqing University Chongqing 400030 China

Flow transitions and instabilities have significant effects on the quality of the crystals. The flow and heat transfer in the LEC GaAs melt are numerically studied by a time-dependent and three-dimensional turbulent flow model. The effects of the change of the buoyancy and Marangoni force on the flow state are analyzed by changing the temperature difference between the crystal and the crucible walls. The results show that the flow will transform from axisymmetric steady flow to non-axisymmetric oscillatory flow when the temperature difference exceeds the critical value, and that the mechanism of the transition is attributed to the Marangoni instability. The critical temperature differences for the flow transitions corresponding to different melt depth H are numerically predicted. Several important characteristics of the non-axisymmetric buoyant-Marangoni convection are numerically observed and compared with that of the non-axisymmetric mixed convection coupled with crystal rotation.

关键词： flow transition flow instability buoyant-Marangoni convection mixed convection LEC GaAs melt