简介：“把”(bǎ)-SentenceisanimportantpartofChineseteaching.Takingbǎ-SentenceintheHSKDynamicCompositionCorpusastheobjectofstudy,thewritersummarizestheerrorsthatforeignstudentsmakewhentheylearnandusethebǎ-Sentence,exploresthecausesoftheseerrorsundertheguidanceofthetheoriesoftheinter-languageanderroranalysis,andgivescorrespondingteachingsuggestionsinthisstudy.

简介：Inthispaper,thecycle’sstructureofembeddedgraphsinsurfacesarestudied.Accordingtothemethodoffundamentalcycles,thesetC(Ccontainsallshortest)isfound.AundirectedgraphGwithnverticeshasatmostO(n5)manyshortestcycles;IftheshortestcycleofGisoddcycle,thenGhasatmostO(n3)manyshortestcycles;IfGhasbeenembeddedinasurfaceSg(Ng,gisaconstant),thenithasatmostO(n3)shortestcycles,moreover,iftheshortestcycleofGisoddcycle,then,GhasatmostO(n2)manyshortestcycles.WecanfindacyclebaseofG,thenumberofoddcyclesofG,thenumberofevencyclesofG,thenumberofcontractiblecyclesofG,thenumberofnon-contractiblecyclesofG,arealldecided.IftheΠ-embeddedgraphGhasΠ-twosidedcycles,then,CcontainsashortestΠ-twosidedcycleofG,thereisapolynomiallyboundedalgorithmthatfindsashortestΠ-twosidedcycleofaΠ-embeddedgraphG,thenewandsimplesolutionsabouttheopenproblemofBojanMoharandCarstenThomassenareobtained.

简介：Thispaperdescribesthestructure,geometricmodelandgeometriccalibrationofPhotogrammetronI-thefirsttypeofphotogrammetronwhichisdesignedtobeacoherentstereophotogrammetricsysteminwhichtwocamerasaremountedonaphysicalbasebutdrivenbyanintelligentagentarchitecture.Thesystemcalibrationisdividedintotwoparts:thein-labcalibrationdeterminesthefixedparametersinadvanceofsystemoperation,andthein-situcalibrationkeepstrackingthefreeparametersinreal-timeduringthesystemoperation.Inavideosurveillanceset-up,preparedcontrolpointsaretrackedinstereoimagesequences,sothatthefreeparametersofthesystemcanbecontinuouslyupdatedthroughiterativebundleadjustmentandKalmanfiltering.

简介：Usingtime-dependentcompressiblelaminarNavier-Stokesequationswithafinitevolumemethodincorporatingathird-order-accuratediscretizationscheme,theflowstructuresaroundaslenderatcertainincidencesarenumericalsimulatedandtypicalcrossflowpatternsarepresented.Atincidence10°,thesevorticalconfigurationsaredifferentatdissimilaraxiallocationsthoughtheyaresymmetric.At35°,thesymmetricvorticalstructuresstillmaintainovertheslender,yettheirinteractionatafterbodyisintensethanthatattheforebodysincethetwovorticeshavefullydevelopeddownstream.Theunstabletopologicalstructureoftrajectoryofsaddle-to-saddlepointsandmultiplelimitcyclearefurtherdiscussedintopologicalstabilitytheory.Thesestructureseasilyproducebifurcationwithperturbation.Theresultssupporttheviewofhydrodynamicinstabilityofvorticesflowfield.

简介：Westudystructure-preservingalgorithmstophasespacevolumeforlineardynamicalsystemsy=Lyforwhicharbitrarilyhighorderexplicitsymmetricstructure-preservingschemes,i.e.thenumericalsolutionsgeneratedbytheschemessatisfydet()=ehtrL,wheretrListhetraceofmatrixL,canbeconstructed.Fornonlineardynamicalsystemsy=f(y)Feng-Shangfirst-ordervolume-preservingschemecanbealsoconstructedstartingfrommodifiedθ-methodsandisshownthattheschemeisstructure-preservingtophasespacevolume.

简介：ＵｎｉｖｅｒｓａｌＳｐｅｃｔｒａｌＭｏｄｕｌａｔｉｏｎＳｅｎｓｏｒｓ：（Ⅰ）ＴｈｅｏｒｙａｎｄＳｔｒｕｃｔｕｒｅ①ＳＨＩＹｏｎｇｊｉ（ＬｕｏｙａｎｇＴｅｃｈｎｏｌｏｇｙＣｏｌｅｇｅ，Ｌｕｏｙａｎｇ４７１００３，ＣＨＮ）Ａｂｓｔｒａｃｔ：Ａｕｎｉｖｅｒ...

简介：在关于闪电放电的物理过程和在在中国的最后十年的雷雨的电的结构的研究的进步被考察了。由使用开发theself的闪电与时间的高度和空间分辨率检测并且定位技术，在在中国的一些代表性的区域的闪电放电的特征和参数被获得了。在闪电活动的观察在2002-2005在Qinghai西藏的高原第一次被进行，并且雷雨的特殊特征和在高原的闪电活动被揭示。在可见的光的乐队的闪电系列被记录，并且光谱线与原子结构的现代理论的介绍详细被识别。这些技术在上人工地，高度触发了闪电，在严厉电磁的环境下面的相关大小好发展。ofbi方向性的领导人繁殖在触发的闪电放电期间借助于光学和甚高频放射被观察的证据。一些闪电保护设备用触发技术的人工的闪电被测试了。另外，在闪电活动和天气和气候之间的关联preliminarily被学习。

简介：Inthispaper,severaldicalciumsilicates（β-C2S）obtainedfromimpuritieshavebeenstudied.AstudyofthestructureandpropertiesofthesedopeddicalciumsilicatesrevealsthatthedopingwithMgOofBaSO4enhancedtheiractivityandrateofhydration,K20hasasimilareffectroughlesspronounced.Thelatticedistortionandcrystalsizeinβ-dicalciumsilicatesaremeasuredbyX-raypowderdiffractiontechnique,thebindingenergiesof2P3forCaand2PforSiareobtainedbyX-rayphotoelectricspectrum,thevibrationsofthechemicalbondsinsilicateanion[SiO4]4-areexaminedbyFT-IRandLaserRamanspectraandtheheatevolutionduringhydrationreactionforβ-dicalciumsilicatesaredeterminedbymicrocalorimetry.FromtheresultsofXRD,XPS,FT-IR,Ramanandmicro-DSC,therelationshipbetweenthemicrostructureandpropertiesofdopeddicalciumsilicatesandthemechanismofactivationduetoimpuritiesarediscussed.

简介：复杂网络的显微镜的结构怎么在流行繁殖上拿影响，被调查。特殊注意对它的平均的度随着时间变化的成长网络被给予。为感染的个人的最后的密度的一个公式被数字模拟给并且被证实。我们的结果证明最后的密度倔强与两个线性地非增加节点和网络结构的可调节的随机的参数的平均的度。

简介：Differentfromthetraditionalone-dimensionalextremevaluestatisticalmethod,practicaldesigncriteriafornearshorestructuredesignarepresentedbasedonjointprobabilitytheoryinthispaper.Theproposedprocedureconsidersthecombinedeffectoftidelevel,hugewavesandwindaffectingcoastalstructures.TheImportanceSamplingProcedure(ISP)isutilizedtosolvethejointdistributionofnon-Gaussiancorrelatedmultivariatedistributions.ThecalculationresultsshowthattheISPisasimulatingtechniquewiththeadvantagesofefficiencyandhighconvergency.Finallytheenvironmentalconditionsaregivenusingthistechniquefornear-shorestructuredesignintheQingdaoarea.

简介：ThispaperpresentsactualityofinvestigationandstudyofthecrustalstructurecharactersofEastChinaSeaathomeandabroad.Basedonlotsofinvestigationandstudyachievementsandthedifferenceofthecrustalvelocitystructurefromwesttoeast,theEastChinaSeaisdividedintothreeparts-EastChinaSeashelfzone,OkinawaTroughzoneandRyukyuarc-trenchzone.TheEastChinaSeasheffzonemostlyhasthreevelocitylayers,i.e.,thesedimentblanketlayer(thevelocityis5.8-5.9km/s),thebasementlayer(thevelocityis6.0-6.3km/s),andthelowercrustallayer(thevelocityis6.8-7.6km/s).SotheEastChinaSeashelfzonebelongstothetypicalcontinentalcrust.TheOkinawaTroughzoneislocatedatthetransitionalbeltbetweenthecontinentalcrustandtheoceaniccrust.Itstillhasthestructuralcharactersofthecontinentalcrust,andnoformationoftheoceaniccrust,butthecrustofthecentraltroughhasbecometothinningdown.TheRyukyuarc-trenchzonebelongstothetransitionaltypecrustasawhole,buttheoceansideofthetrenchalreadybelongstotheoceaniccrust.AndthenorthwestPhilippineBasintotheeastoftheRyukyuTrenchabsolutelybelongstothetypicaloceaniccrust.

简介：在大约431nm的蓝光在C+培植以后从取向附生的硅被获得，在顺序蚀刻的氢环境和化学药品退火。随化学蚀刻的增加，蓝山峰起初被一座红山峰最后提高，然后减少了并且代替。C=O混合物在C+培植期间被介绍并且在纳米Si的表面嵌入在退火期间形成了，并且最后被形成纳米硅与嵌入结构，它贡献蓝排放。介绍是光致发光的可能的机制。

简介：CADprocessforstructuredesignofboxculvertisintroduced.Itfollowsthetraditionalwayofculvertdesign.Allworkingconditionsofculvertaretakenintoaccount.Itcangenerateloaddiagram,bendingmomentdiagramandbendingmomentenvelopediagramforasingle-hole,double-holeortriple-holeboxculvert.Thatistosay,thewholeCADprocessfortheboxculvertstructuredesignisrealizedwiththeself-developedsystem.IthasbeenusedtoaccomplishseveralprojectsinChinaandtheresultsaresatisfactory.

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简介：TheatomicstructureofanovelrareearthcomplexconsistingofNdandthesulfur-containingligandpipdtc(C5H10NCS2^-)hasbeenstudiedwithextendedx-rayabsortpitonfinestructure(EXAFS)andx-raydiffractiontechniques.ThecomplexofformulaNd(pipdtc)4N(CH3)4crystallizaesinthemonoclinicspacegroupP21/nwiththefollowinglatticeparameters,a=22.685(2),b=20.332(2),c=17.1270(10)A,β=100.570(10)°.Z=8,thecalculateddensityis1.47g/cm^3,Anewderivativemethodisusedtoremovethepiost-edgeabsorptionbackgroundincludingthemultielectronexcitationeffect.TheEXAFSresultsdemonstratethatthereareabouteightSandfourOatomsaroundNdwiththeNd-Sbondlengthof2.916AandtheNd-Obondlengthof2.415A,respectively.Thisimpliesthatthepowderofthiscomplexisnotstableandiseasytooxidizeinair.Thepossiblechangeofstructurebeforeandafteroxidationisdiscussed.

简介：ＰｒｏｊｅｃｔｉｏｎｏｆＣｈａｎｇｅｉｎｔｈｅＡｇｅＳｔｒｕｃｔｕｒｅｏｆｔｈｅＷｏｒｌｄＰｏｐｕｌａｔｉｏｎＢｙｔｈｅｍｉｄ－２１ｓｔｃｅｎｔｕｒｙ，ｔｈｅｗｏｒｌｄｐｏｐｕｌａｔｉｏｎｉｓｐｒｏｊｅｃｔｅｄｔｏｔｏｐｔｅｎｂｉｌｌｉｏｎ，ｏｆｗｈ...

简介：ThestudiesonthestructureandphysicalpropertiesoftheEarth'sinteriordonebyChinesegeophysicistsfrom1999to2002werereviewedinthispaper.Itincludesseveralresearchareas:thestructureoftheEarth'sinteriorsusingseismictomography,anisotropyoftheuppermantleinChinaanditsadjacentareas,qualityfactorQβforSwaves,subductionzone,mantlediscontinuities,physicalpropertiesofEarth'smaterialsandothers.Thereviewconcernsmainlythecontents,themethodsandtheresultsofthestudies.ItcanbeseenthatnewprogressinthestudyonthestructureandphysicalpropertiesoftheEarth'sinteriorhasbeenmadeinthelast4yearsinChina.Itisshownonthreeaspects:advancementmadeonsomepreexistentareas;pioneeringonsomenewfieldsandnewmethodsadopted.

简介：

简介：Thepedestalcharacteristicisanimportantbasisforhighconfinementmode(Hmode)research.BecauseofthefinitespatialresolutionofThomsonscattering(TS)diagnosticonExperimentalAdvancedSuperconductingTokamak(EAST),itisnecessarytocharacterizethepedestalwithasuitablefunctionalform.BasedonsimulatedandexperimentaldataofEAST,itisshownthatthetwo-linemethodwithabilinearfittinghasbetterreproducibilityofpedestalparametersthanhyperbolictangent(tanh)andmodifiedhyperbolictangent(mtanh)methods.ThismethodhasbeenappliedtoEASTtypeIedgelocalizedmode(ELM)discharges,andtheelectronpedestaldensityisfoundtobeproportionaltotheline-averageddensityandtheedgepressuregradientisfoundtobeproportionaltothepedestalpressure.Furthermore,theionpoloidalgyro-radiushasbeenidentifiedasthesuitableparametertodescribethepedestalpressurewidth.

简介：WithcomparisonofdemographicchangesbetweenthedevelopedEuropeancountriesandChina,thispaperhasdiscussedtheshortcomingsoftheWesterndemographictransitiontheories.Furthermore,thepaperhasproposedthedirectionofdemographictransitionandthecriteriaofsuchtransition'scompletion.Withtheestablishmentofage-structuretransitiontheory,andhelpedwithstrictdefinitionsofbothsurpluspopulationandappropriatepopulation,thepaperpointsoutthedistinctionofdemographicage-structurebetweenthosedevelopingcountriesthatareundergoingdemographictransitionandthosedevelopedcountrieswithanearcompletionofsuchdemographictransition.FinallyitconcludesthatChina'stransitionofagestructureismovingtowardsafeasibledirection.