简介:Asimplifiedmultisupportresponsespectrummethodispresented.Thestructuralresponseisasumoftwocomponentsofastructurewithafirstnaturalperiodlessthan2s.Thefirstcomponentisthepseudostaticresponsecausedbytheinconsistentmotionsofthestructuralsupports,andthesecondisthestructuraldynamicresponsetogroundmotionaccelerations.Thismethodisformallyconsistentwiththeclassicalresponsespectrummethod,andtheeffectsofmultisupportexcitationareconsideredforanymodalresponsespectrumormodalsuperposition.Iftheseismicinputsateachsupportarethesame,thesupportdisplacementscausedbythepseudostaticresponsebecomerigidbodydisplacements.Theresponsespectruminthecaseofmultisupportexcitationsthenreducestothatforuniformexcitations.Inotherwords,thismultisupportresponsespectrummethodisamodificationandextensionoftheexistingresponsespectrummethodunderuniformexcitation.Moreover,mostofthecoherencycoefficientsinthisformulationaresimplifiedbyapproximatingthegroundmotionexcitationaswhitenoise.Theresultsindicatethatthissimplificationcanreducethecalculationtimewhilemaintainingaccuracy.Furthermore,theinternalforcesobtainedbythemultisupportresponsespectrummethodarecomparedwiththoseproducedbythetraditionalresponsespectrummethodintwocasestudiesofexistinglong-spanstructures.Becausetheeffectsofinconsistentsupportdisplacementsarenotconsideredinthetraditionalresponsespectrummethod,thevaluesofinternalforcesnearthesupportsareunderestimated.Theseregionsareimportantpotentialfailurepointsanddeservespecialattentionintheseismicdesignofreticulatedstructures.
简介:Temporalandspatialevolutioncharacteristicsofthe30-60dayoscillation(intraseasonaloscillation,ISO)ofsummerrainfallinChinaandtheeffectsofEastAsianmonsoonontherainfallISOareanalyzedinthispaper.Resultsshowthattheannualanddecadalvariationsoftheoscillationexistbetween1960and2008,andtheintensityisweakestinthelate1970sandearly1980s.InthetypicalstrongyearsoftherainfallISOobtainedfromempiricalorthogonalfunctions(EOFmode1),ananticycloneisinnorthwesternPacificandacycloneisintheeastofChina.Inthetypicalweakyears,thewindISOismuchweaker.Thelow-frequencyzonalwindandwatervaportransportfromthelowlatitudestomid-latitudesinthetypicalstrongyears,andtheoscillationstrengthofdiabaticheatingismuchstrongerthanthatintheweakyearsoftherainfallISO.TheanomalycharacteristicsoftherainfallISOshowanti-phasesbetweentheYangtzeRiverbasinandsouthofChina.AsforthetypicalstrongyearsoftherainfallISOintheYangtzeRiverbasin(EOFmode2),themainoscillationcenterofwatervaporisintheeastofChina(20-30°N,110-130°E).Inthepeak(break)phaseoftherainfalloscillation,alow-frequencycyclone(anticyclone)isintheYangtzeRiverbasinandananticyclone(cyclone)isnearTaiwanIsland.Inaddition,thepeakrainfallcorrespondstotheheatsourceintheYangtzeRiverbasinandtheheatsinkintheQinghai-TibetPlateau.AsforthetypicalstrongyearsoftherainfallISOinthesouthofChina,themainoscillationcenterofwatervaporissouthof20°N.Inthepeak(break)phaseoftherainfallISO,alow-frequencycyclone(anticyclone)isinthesouthofChinaandananticyclone(cyclone)isinthePhilippines.ThepeakrainfallcorrespondstotheheatsourceinthesouthofChinaandtheSouthChinaSea,andtheheatsinkinthewestofIndochina.
简介:Analfistulaisoneofthethreegreatestanorectaldiseaseswithahighprevalence.Thetraditionaltreatments(e.g.,surgery)forfistulahavelimitationsduetodamagetotheinternalanalsphincterofpatients.Withrecentadvancesinbiomaterials,treatmentsbasedonbiomaterialfilling(e.g.,scleraproteininjection,fistulaplug)haveemergedasnoveltherapiesforfistula.Theanalfistulaplug(e.g.,basedonsmallintestinalsubmucosa(SIS))hasattractedincreasingattentionbecauseofshorttermhealingrateandbiocompatibility.However,challengesremainforthismethodsuchasplugfallingasobservedinclinics.Toaddressthis,thispaperanalyzesthecaseofSISfallingunderphysiologicalconditionfrommechanicalpointofviewusingANSYSsimulation.Itthenproposesthreenewgeometricalstructuresforfistulaplugandcomparestheirmechanicalbehavior(e.g.,axialstress,reactionofconstraint)withthatofclinicallyusedstructure(coneshape).Basedonthesimulation,itoptimizesthegeometricparametersoffistulaplug.Theapproachdevelopedherecanhelptoimprovethedesignoffistulaplugforbetterclinicaltreatments.
简介:Thepatternofprecipitation,includingprecipitationamount,frequencyandintensity,maychangeinthefutureaccordingtothepredictionofclimatechange.Inaridzones,thesoildynamics,plantgrowthandvegetationchange,desertificationandhydrologymightbeaffectedbyprecipitationchange.Ingeneral,theprecipitationinextremearidzoneandaridzoneshowedanincreasetendencywhereastheprecipitationinsomeareainsemi-aridzoneandsub-humidaridzoneshowedadecreasetendency.Theincreaseofprecipitationcouldenhancethegrowthofbiologicalsoilcrust,improvesoilwaterstatus,promoteplantgrowth,increasevegetationcoverage,facilitatethechangefromdesertvegetationtograsslandvegetation,anditisbenefittothereversionoflanddesertification.Inaddition,theincreaseofprecipitationcouldalsoincreasetheriverrunoff,lakestorageandpromotetheoccurrenceofflood,whilethedecreaseofprecipitationhastheadverseeffect.Thesestudieswillbenefitthepredictionofthepossibleresponseofecosystemprocessestothepotentialchangeofprecipitationpatterninaridzonesinthefuture,anditisimportanttotheconservationofnaturalvegetationandthecontrolofdesertification.Morefieldexperimentsandstudiesshouldbeconductedinthefuture,includingtheeffectofincreasedprecipitationortemperature,nitrogendepositionandCO2onsoil,vegetation,desertificationandhydrologyofaridzones,soasthemorepersuasiveresultscouldbeobtainedfromtheseexperimentsandstudies.
简介:Nonlineardynamicresponseofnanomechanicalresonatorisofveryimportantcharacteristicsinitsapplication.Twocategoriesofthetension-dominantandcurvature-dominantnonlinearitiesareanalyzed.Thedynamicnonlinearityoffourbeamstructuresofnanomechanicalresonatorisquantitativelystudiedviaadimensionalanalysisapproach.Thedimensionalanalysisshowsthatforthenanomechanicalresonatoroftension-dominantnonlinearity,itsdynamicnonlinearitydecreasesmonotonicallywithincreasingaxialloadingandincreasesmonotonicallywiththeincreasingaspectratiooflengthtothickness;thedynamicnonlinearitycanonlyresultinthehardeningeffects.However,forthenanomechanicalresonatorofthecurvature-dominantnonlinearity,itsdynamicnonlinearityisonlydependentonaxialloading.Comparedwiththetension-dominantnonlinearity,thecurvature-dominantnonlinearityincreasesmonotonicallywithincreasingaxialloading;itsdynamicnonlinearitycanresultinbothhardeningandsofteningeffects.Theanalysisonthedynamicnonlinearitycanbeveryhelpfultothetuningapplicationofthenanomechanicalresonator.
简介:为高周波的表面的硼氮化物(BN)电影声学的波浪(锯)设备被无线电在Ti/Al/Si(111)晶片上扔频率(RF)磁控管劈啪作响。BN电影的结构被Fourier变换调查红外线(FTIR)光谱学和X光检查衍射(XRD)系列,和表面形态学和BN电影的压电的性质被原子力量显微镜学(AFM)描绘。结果证明当氮和氩的流动比率是2:18时,立方的BN(c-BN)电影与高纯净和c轴取向被扔,并且当氮和氩的流动比率是4:20时,六角形的BN(h-BN)电影与高c轴取向被扔。粒子一致、紧缩,并且粗糙分别地是1.5nm和2.29nm。h-BN电影比c-BN电影有更好压电的反应和分发。
简介:Humanimmunodeficiencyvirus(HIV)hashadaninsightfulimpactaboutthestateofhealthinessofhumanimmunesystem.Duetogreatimprovementindrugtherapy,HIVinfectionshavebeenreducedby17%overthepasteightyears.IthasbeenprovedthatmosteffectivetreatmentHAART(HighlyActiveAntiRetroviralTherapy)mainlycontrolsthediseasesprogressionbutitdoesnoteradicatethediseasescompletely.ReverseTranscriptaseInhibitordrugsspeciallyassociatedwithvirusspecificCytotoxicT-Lymphocyte(CTL)thatdeclineswithdiseaseprogression.CTLresponsesagainstAIDSpathogenesiscouldbepotentialinthedynamicsofvirusreplication,recognitionandclearanceofinfectedcells.InthisresearcharticleamathematicalmodelhasbeenproposedonthebasisofCTLresponsesuppressioninthechronicphaseofinfectionduetopresenceofvirus.WealsoconsiderthegrowthoftheviruspopulationfromtheinfectedCD4~+Tcellsbuddingprocessandfromtheotherinfectedcellslikemacrophagesandthymocytes.Ouranalyticalandnumericalstudiesareconsistentwithexistingobservationsfromalliedareas.
简介:氮使用效率(NUE)在中国是很低的,差不多70%应用的氮化肥的损失在high-yielding稻田被报导。以便调查高亲密关系的铵运输或举起的分子的基础进米饭(OryzasativaL.),我们分析了九铵的表示侧面transporters(AMT),OsAMT1的三各个,OsAMT2和OsAMT3,根据外部N地位在象在这些表示模式的变化一样的米饭生长的二个不同N要求阶段(年轻幼苗阶段和tillering阶段)使用即时反向的抄写聚合酶链反应(RT-PCR)。结果建议九OsAMT基因在米饭植物的不同机关被表示,包括成熟的根,新根,茎,旧叶子和新叶子并且表示模式是相应蛋白质的位置在种系发生的树上特定、独立的机关。OsAMT1;1,3;2和3;3在根和射击被表示,首先旧的叶子,OsAMT1;2和1;3主要在根,和OsAMT2;1,2;2,2;3和3;1主要在射击,首先在新叶子,并且相对更在里面茎比另外的基因。在二个不同N要求阶段的表示模式是一样;在有更大的N要求的tillering阶段,然而,OsAMTs抄本层次比在有低N要求的年轻幼苗阶段的那些大。为48h的N饥饿起来调整的OsAMT1;1,1;2,3;1,3;2,3;3并且下面调整的OsAMT1;3mRNA丰富。后面的N饥饿,NH4+和NH4NO3再供给下面调整的OsAMT1;2和3;3并且起来调整的OsAMT1;3,而NO3再供给下面调整的OsAMT1;1和1;2。这些建议OsAMT的器官特定的表示模式能被N要求和外部N地位调整。
简介:MassselectionforfastgrowthwasconductedinthreePacificoyster(Crassostreagigas)stocksfromChina,JapanandKoreausingpreviouslyestablishedlines(CS1,JS1,andKS1).Todeterminewhethercontinuousprogresscanbeachievedbyselectionforgrowth,theprogenyofthreesecond-generationPacificoysterlineswasselectedforshellheightandevaluatedviaa400-dayfarmingexperiment.Whenharvestedattheendoftheexperiment,theselectedcrossesofCS2,JS2,andKS2linesgrewby9.2%,10.2%and9.6%largerthanthecontrolcrosses,respectively.Duringgrow-outstage,thegeneticgainofthreeselectedlineswas(10.2±1.4)%,(10.4±0.3)%,and(8.4±1.6)%,respectively;andthecorrespondingrealizedheritabilitywas0.457±0.143,0.312±0.071and0.332±0.009,respectively.Theseresultsindicatedthattheselectionforfastgrowthachievedsteadyprogressinthesecondgenerationofoyster.OurworkprovidessupportiveevidenceforthecontinuityofthePacificoysterselectivebreedingprogram.
简介:Time-temperaturesuperpositionprinciple(TTSP)wasusedtoexaminedynamicviscoelasticpropertiesofChineseFir(Cunninghamialanceolata)woodatanextremelylowmoisturecontent(0.6%).Storagemodulusandlossfactordatawereobtainedatdifferentconstanttemperaturesrangingfrom25℃to150℃infrequencymultiplexingexperiments(0.1-20Hz).Allviscoelasticcurvesatothertemperatureswereshiftedalongthelog-frequencyaxistosuperimposethemonareferencetemperature(i.e.135℃inthisstudy)curve.Theextendedstoragemodulusandlossfactorisothermalmastercurveswereoverawiderangeoffrequency.TheshiftfactorsweredeterminedtobeafunctionoftemperatureandfittedintotheArrheniusequationwiththeleastsquaresmethod.TheresultsshowedthatthestoragemodulusdatawereexcellentlyfittedintotheArrheniusmodel,indicatingthevalidityofthemodeltocharacterizethedynamicstiffnessbehaviorofdrywoodintherangeof25-150℃usingtheTTSP.However,thetime-temperatureequivalencewasnotabletopredictthedampingproperties.
简介:纸象精力生产,消费和工业废物水的全部的分泌物的严肃中心的变化的决心一样在所有省和自治区域论述全部的精力生产和消费的预言,经由从1978~2009的精力和在由美国通用汽车公司(1,1)模型和严肃中心模型,纸也在精力产品处于地区性的差别基于分析动态变化的使用的中国的环境优秀数据的中国的气体和残余结果如下被显示出。1)精力生产的严肃中心逐渐地正在移动向西南并且全部运动轨道接近到线性变化,显示在东方和西方,南方和北方之间的精力生产的差别正在变窄到某个程度,在南方和北方之间比那快与东方和西方之间的差别变窄。2)精力消费的严肃中心正在移动与可察觉的变化,从2000~2005的严肃中心位置是相对稳定的与细微年度位置变化,基本上显示所有省和自治区域的生长率是向西南一样。3)工业废物水,气体和残余的全部的分泌物的严肃中心被变化在经度和纬度描绘到某个度。但是,它总体上显示出一个向西南的趋势。4)在精力生产与中国,和工业废物水的全部的分泌物的和那的严肃中心的比较分析的消费的严肃中心的变化课程有共同点和差异,气体和残余证明环境优秀水平仔细与精力生产和消费(特别精力消费)被联系,显示在精力的经济的环境费用在中国是更高的。
简介:Anintegralanalyticprocessfromquantificationtopropagationbasedonlimiteduncertainparametersisinvestigatedtodealwithpracticalengineeringproblems.Anewmethodbyuseofthesmallestinterval-set/hyper-rectanglecontainingallexperimentaldataisproposedtoquantifytheparameteruncertainties.Withthesmallestparameterinterval-set,theuncertaintypropagationevaluationofthemostfavorableresponseandtheleastfavorableresponseofthestructuresisstudiedbasedontheintervalanalysis.Therelationshipbetweentheproposedintervalanalysismethod(IAM)andtheclassicalIAMisdiscussed.Twonumericalexamplesarepresentedtodemonstratethefeasibilityandvalidityoftheproposedmethod.
简介:Inthisstudy,weanalyzetheco-seismicresponseofwaterlevelsintheJiajiwelltostrongearthquakes(MS≥7.8)from2001to2010atanepicentraldistancelessthan8000km.Weinvestigatedtheco-seismicvariationformofwaterlevels,andanalyzedtherelationshipbetweentheamplitudeofwaterlevelvariationandthemagnitudeandtheepicentraldistance.Wethencheckedtheseismicwavephaseswhenthechangesofwaterleveloccurred.Itwasshownthat:(1)thewaterlevel'sco-seismicresponseismainlycharacterizedbyescalationwithnooscillation;(2)theamplitudeofwaterlevelchangehasacertainconnectionwithepicentraldistanceandmagnitude;(3)co-seismicresponseofwaterlevelsintheJiajiwellshowsacertaindirectivity;(4)mostoftheco-seismicresponseswerecausedbysurfacewaves,andsomebylong-periodSwaves.
简介:装载的风是为控制大跨度的房顶结构的设计的最重要的负担之一。相等的静态的风负担,能通常瞄准决定特定的回答,被结构的设计者广泛地使用。为对多反应适用的相等的静态的风负担的一个方法在这份报纸被建议。相应于特别山峰回答的一个修改loadresponse-关联(纵向冗余码校验)方法被介绍,并且类似算法实现了因为组反应被描述。算法的主要想法是二回答能被放进一个组如果一回答的价值接近另外的反应的,当结构受到瞄准另外的反应的相等的静态的风负担时。基于修改纵向冗余码校验,组织反应方法被提出到装载的构造等价物静电干扰风。这种技术能同时为一些组织回答复制山峰回答。验证它的计算精确性,方法被用于实际大跨度的房顶结构。计算结果看那在一样的组的回答的类似什么时候高,有高精确性的相等的静态的风负担和相等的静电干扰的合理大小弯屈分发能被完成。