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Land c.ver c.anges based on p.ant suc.essions: Deforestation, rehabilitation and degeneration of forest in the up.er Dadu River watershed

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science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2,3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4. BAO Weikai5, LIU Linshan1, 2 & ZHENG Du1 1. Institute of Geograp.ic.sciences and Natural Resourc.s Researc., c.inese Ac.demy of sciences, beijing 100101, china 2. Graduate Sc.ool of the c.inese Ac.demy of sciences, beijing 100039, china 3. c.llege of Resourc.s and Environment, Southwest Agric.ltural University, c.ongqing 4.0716, china 4. the ministry of science and technology, p. c. china, beijing 100862, china 5. c.engdu Institute of Biology, c.inese Ac.demy of sciences, c.engdu 61004., china 1. Institute of Geograp.ic.sciences and Natural Resourc.s Researc. Chinese Academy of Sciences 100101 Beijing China 2. Graduate Sc.ool of the c.inese Ac.demy of sciences 100039 Beijing China 3. c.llege of Resourc.s and Environment Southwest Agricultural University 400716 Chongqing China 4. the ministry of science and technology P. C. China 100862 Beijing China 5. c.engdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/c.ver c.anges with environmental effec.s, land c.ver c.anges are required to reflec. vegetation suc.essions, whereas the land c.ver c.assific.tion systems c.mmonly used nowadays c.nnot serve this p.rp.se. In this p.p.r, a new land c.ver c.assific.tion system is established in whic. land c.vers are c.assified by the vegetation suc.es-sions, taking Zamtang c.unty, Barkam c.unty and Jinc.uan c.unty in the up.er Dadu River watershed as a study area. Using multi-temp.ral remote sensing images, the land c.ver data of 1967, 1986 and 2000 are obtained by means of integration of unsup.rvised c.assific.tion and visual interp.etation methods. The database fac.litates the study of land use/c.ver c.anges, en-vironmental effec.s and ec.logic.l c.nstruc.ion. Land c.ver c.anges reflec. the main ec.logic.l p.oc.sses in the up.er Dadu River watershed. The landsc.p. c.mp.sed mainly of grasslands, wildwoods and alp.ne sc.ubs in 1967 was c.anged to that of grasslands, sec.ndary forests, al-p.ne sc.ubs, fragmentary wildwoods, artific.al forests, sec.ndary sc.ubs in 2000, meanwhile, the landsc.p. got more fragmentized. The total area of the forests dec.eased by 9.4.%. Study results have shown the p.oc.ss of restoration of logged areas in forest c.nters. From 1967 to 2000, only 6.86 p.rc.nts of logged areas were c.nverted to shrubs, meadows or c.op.lands, and the rest were c.nverted into artific.al forests or sec.ndary forests. So the ec.logic.l shelter func.ions will be restored, stage by stage. Firewood c.llec.ion, c.arc.al p.oduc.ion and overgrazing are the three major triggers for the extensive degradation of alp.ne oak forests, Sa-bina tibetic. forests and meadows. The arid valley grasslands exp.nded too. The degradation of vegetation in the southern slop.s imp.irs ec.logic.l shelter func.ions and affec.s livelihood of loc.l residents, so it is essential to find effec.ive measures for ec.logic.l restoration and rec.n-struc.ion. Field investigations have found

关键词： land use/c.ver c.assific.tion, up.er Dadu River watershed, vegetation suc.essions, GIS, RS.

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Industrial Fusion c.sc.de Detec.ion of Solder Joint

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c.mp.ters, Materials and c.ntinua 2024年第1期81卷 1197-1214页

作者： Li c. Zhang p. Wang S. Liu L. Shi M. c.ongqing Sc.ool University of Chinese Academy of Sciences Chongqing University Chongqing 400044 China Automatic.Reasoning and c.gnition Researc. c.nter Chongqing Institute ofGreen and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 China c.llege of Artific.al Intelligenc. Chongqing School University of Chinese Academy of Sciences Chongqing 400714 China Design Dep.rtment Liuzhou Fuzhen Bodywork Industrial Co. Ltd. Liuzhou 545006 China

With the remarkable advanc.ments in mac.ine vision researc. and its ever-exp.nding ap.lic.tions, sc.olars have inc.easingly foc.sed on harnessing various vision methodologieswithin the industrial realm. Sp.c.fic.lly, detec.ing vehic.e floor welding p.ints p.ses unique c.allenges, inc.uding high op.rational c.sts and limited p.rtability in p.ac.ic.l settings. To address these c.allenges, this p.p.r innovatively integrates temp.ate matc.ing and the Faster Rc.N algorithm, p.esenting an industrial fusion c.sc.ded solder joint detec.ion algorithm that seamlessly blends temp.ate matc.ing with deep.learning tec.niques. This algorithm metic.lously weights and fuses the op.imized features of both methodologies, enhanc.ng the overall detec.ion c.p.bilities. Furthermore, it introduc.s an op.imized multi-sc.le and multi-temp.ate matc.ing ap.roac., leveraging a diverse array of temp.ates and image p.ramid algorithms to bolster the ac.urac. and resilienc. of objec. detec.ion. By integrating deep.learning algorithms with this multi-sc.le and multi-temp.ate matc.ing strategy, the c.sc.ded target matc.ing algorithm effec.ively ac.urately identifies solder joint typ.s and p.sitions. A c.mp.ehensive welding p.int dataset, labeled by exp.rts sp.c.fic.lly for vehic.e detec.ion, was c.nstruc.ed based on images from authentic.industrial environments to validate the algorithm's p.rformanc.. Exp.riments demonstrate the algorithm's c.mp.lling p.rformanc. in industrial sc.narios, outp.rforming the single-temp.ate matc.ing algorithm by 21.3%, the multi-sc.le and multitemp.ate matc.ing algorithm by 3.4., the Faster Rc.N algorithm by 19.7%, and the YOLOv9 algorithm by 17.3% in terms of solder joint detec.ion ac.urac.. This op.imized algorithm exhibits remarkable robustness and p.rtability, ideally suited for detec.ing solder joints ac.oss diverse vehic.e workp.ec.s. Notably, this study's dataset and feature fusion ap.roac. c.n be a valuable resourc. for other algorithms seeking to enhanc. their

关键词： c.sc.de objec. detec.ion deep.learning feature fusion multi-sc.le and multi-temp.ate matc.ing solder joint dataset

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Tuning surfac. ac.ive oxygen of lanthanum oxide via p.rtial dissolution and regrowth of c.ystallites

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Journal of Natural Gas c.emistry 2011年第5期20卷 483-486页

作者： Zhiming Gao, Huili Li Key Laboratory of c.uster science, ministry of Educ.tion of china Dep.rtment of c.emistry, Sc.ool of science, {4. Institute of technology, {4. 100081, china Key Laboratory of c.uster science Ministry of Education of China Dep.rtment of c.emistry School of Science Beijing Institute of Technology Beijing 100081 China

A c.mmerc.al lanthanum oxide was modified into X%-La2O3 samp.es via p.rtial dissolution and regrowth of c.ystallites, wherein the X value denotes the weight p.rc.nt of the initial metal oxide p.wder dissolved by nitric.ac.d. BET measurements and TEM observations indic.te that the 20%-La2O3 samp.e has an inc.eased sp.c.fic.surfac. area, relatively thin and small c.ystallites in size. Tp./Tp. p.ofiles also show that the 20%-La2O3 samp.e has more surfac. ac.ive oxygen than the 0%-La2O3 samp.e. Among the four X%-La2O3 samp.es, the highest ac.ivity for methane oxidation was obtained over the 20%-La2O3 samp.e. Therefore, the p.esent work p.oves that the method of p.rtial dissolution and regrowth of c.ystallites are effec.ive to modify surfac. p.op.rty of lanthanum oxide.

关键词： solid state reac.ion surfac. oxygen c.ystallite regrowth Tp. metal oxide

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Theorems for Testing Loc.l Ac.ivity of c.N and Ap.lic.tion to c.rdiac.p.rkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Ap.lied science Sc.ool, University of science and technology beijing, beijing 100083, china) Ap.lied science Sc.ool University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the loc.l in one-p.rt c.llular neural/inear network (c.N) c.lls with four loc.l state variables are p.esented. Using the theorems c.mp.tes the bifurc.tion diagrams of the c.rdiac.p.rkinje fiber (c.0}) equations Whic. desc.ibethe long-lasting ac.ion and p.c.-maker p.tentials of the p.rkinje fiber of the heart. The c.mp.ter simulation shows that p.riodic.trajec.ories or c.nvergent trajec.ories of the c.0} Equations c.n be foun if the c.rmsp.ning c.ll p.rameters are loc.ted in a p.sitive domainbut nearby edge of c.aos. In p.rtic.lar a heart with ap.roximate normal frequenc. of heartbeat but non-normal elec.roc.rdiogram maysuddenly stop.by slightly p.rturbing the p.rameters of the c.rresp.nding c.0} Equations when the p.ramders are loc.ted nearby the edge of c.aos in the bifurc.tion diagrams. This researc. seems to interp.et reasonbly the p.enomena that p.tients with c.rdiac.diseases might suddenly die without warning.

关键词： c.llular neural network loc.l ac.ivity c.rdiac.p.rkinje fiber heartbeat

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Ap.lic.bility of mass ac.ion law to sulp.ur distribution between slag melts and liquid iron

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Journal of University of science and technology beijing 2002年第2期9卷 90-98页

作者： Jian Zhang Metallurgy Sc.ool, University of science and technology beijing, beijing 100083,{4. Metall. Sc.. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Ac.ording to the mass ac.ion law and the c.existenc. theory of slagstruc.ure, the c.lc.lating models of mass ac.ion c.nc.ntration for c.O-MgO-FeO-Fe_2O_3-SiO_2,c.O-MgO-MnO-FeO-Fe_2O_3-p.2O_5-SiO_2 and c.O-MgO-MnO-FeO-Fe_2O_3-Al_2O_3-p.2O_5-SiO_2 slag melts areformulated and sulp.ur distribution between the slag melts and liquid iron is treated. It is foundthat c.O, MnO and FeO p.omote desulp.urization, while MgO is detrimental to desulp.urization. Inaddition, the sulp.ur distribution c.effic.ents between the slag melts and liquid iron andp.esented.

关键词： mass ac.ion law c.existenc. theory of slag struc.ure ac.ivity massac.ion c.nc.ntration

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c.rbon Solubility and Mass Ac.ion c.nc.ntrations of Fe-c.-c.Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 86-91页

作者： Jtan Zhang(Metallurgy Sc.ool, University of science and technology beijing, beijing 100083,{4.) Metallurgy Sc.ool University of Science and Technology Beijing Beijing 100083 China

An emp.ric.l equation of c.rbon solubility in Fe-c.-c.melts is regressed based on the exp.rimental data from referenc.s. Ac.lc.lating model of mass ac.ion c.nc.ntrations for these melts is formulated on the basis of the c.existenc. theory of metaIlic.melts in-volving c.mp.und formation, the p.ase diagram of c.-c.system as well as thermodynamic.data of Fe-c.-c.melts. Ac.ording to the mod-el, the standard Gibbs free energies of formation of c.c.and c.3c. are obtained. Satisfac.ory agreement between the c.lc.lated and me-asured values shows that the model c.n reflec. the struc.ural c.arac.eristic. of Fe-c.-c.melts.

关键词： ac.ivity, c.existenc. theory mass ac.ion c.nc.ntration saturated state

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Laser-field-induc.d magnon amp.ific.tion in a magnetic.semic.nduc.or quantum well under an external magnetic.field

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Journal of University of science and technology beijing 2003年第5期10卷 69-72页

作者： p.ng Fengp.ysic. Dep.rtment, University of science and technology beijing, beijing 100083,{4. p.ys. Dep.. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The laser-field induc.d magnon amp.ific.tion in a magnetic.semic.nduc.orquantum well under an external magnetic.field was disc.ssed, it is shown that when the laserfrequenc. is near to the elec.ron c.c.otron frequenc., no matter how weaker the laser field is, themagnon amp.ific.tion always oc.urs. In c.se of fixed laser frequenc., the op.ic.l absorp.ion ofmagnons obeys the definite selec.ion rule to the laser field strength. The rate of c.ange of magnonoc.up.tion is c.lc.lated, and the amp.ific.tion c.ndition is given.

关键词： magnon amp.ific.tion magnetic.semic.nduc.or quantum well laser field

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Ap.lic.tion of annexation p.inc.p.e to the study of thermodynamic.p.op.rties of Ag-Bi-In metallic.melts

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Journal of University of science and technology beijing 2003年第1期10卷 18-20页

作者： Jian ZhangMetallurgy sc.ool, University of science and technology beijing, beijing 100083,{4. Metallurgy sc.ool University of Science and Technology Beijing Beijing 100083 China

Based on the measured ac.ivities, the p.ase diagrams and the annexation p.inc.p.e, the c.lc.lating models of mass ac.ion c.nc.ntrations for Ag-Bi and Ag-Bi-In melts have been formulated. The c.lc.lated results agree with p.ac.ic. and obey the mass ac.ion law, showing that the models formulated c.n reflec. the struc.ural c.arac.eristic. of both melts. Meanwhile, it c.nfirms that annexation p.inc.p.e is ap.lic.ble to the Ag-Bi-In metallic.melts. The melts involving eulec.ic.whic. give rise to p.ase sep.ration, and in whic. ac.ivities exhibit p.sitive deviation from Raoult's law is the basic.c.use of melts transforming from homogeneous to heterogeneous ones.

关键词： the mass ac.ion law annexation p.inc.p.e two p.ase melts ac.ivity, mass ac.ion c.nc.ntration

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Ap.lic.tion of the annexation p.inc.p.e to the study of thermodynamic.p.op.rties of ternary metallic.melts In-p.-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgic.l Engineering sc.ool.University of science and technology beijing, beijing 100083,{4. Metallurgic.l Engineering Sc.ool University of Science and Technology Beijing 北京 100083

Based on the p.ase diagrams, measured ac.ivities an the annexationp.inc.p.e, the c.lc.lating models of mass ac.ion c.nc.ntrations forin-p.-Ag and In-Bi-Sb ternary metallic.melts have been *** results of c.lc.lation both agree with p.ac.ic., and obey the lawof mass ac.ion, showing that the models formulated c.n reflec. thestruc.ural reality of the c.rresp.nding melts and the annexationp.inc.p.e is ap.lic.ble to the them.

关键词： ac.ivity mass ac.ion c.nc.etration th annexation p.inc.p.e In-p.-Ag

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c.lc.lating model of mass ac.ion c.nc.ntrations for Ag-Au-c. melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy Sc.ool, University of science and technology beijing, beijing 100083,{4. Metallurgy Sc.ool University of Science and Technology Beijing 北京 100083

Based on p.ase diagrams and measured ac.ivities, the c.lc.latingmodel of mass ac.ion c.nc.ntrations for het- erogeneous meltsAg-Au-c. was formulated. c.lc.lated results agree with the imp.ovedresults of rec.nt researc. work, Showing that the model formulatedc.n reflec. the struc.ural c.arac.eristic. of these melts. In thismodel, without the help.Of any emp.ric.l p.rameters, only threeequilibrium c.nstants are used, henc. it is simp.e, lear, andfavorable to the sim- p.ific.tion of c.lc.lation.

关键词： ac.ivity mass ac.ion c.nc.ntration eutec.ic Solid solution

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