简介:Inthispaper,theinterestingdevelopmentoftheveryimportantinnovationofthrustvestoringtechnologyinappliedaerodynamicsisdescribed.InMemoryofafirend.Dr.W.HerbstofMBB,Germany,theso-calledfatheroftheX-31experimentalthrustvectoringfighter,wholosthislifeafewyearsagowhilepilotinghisprivateairplane.BertrandRussel:“Menarebornignorant,notstupid-theyaremadestupidbyeducation.”.AdmiralHymanRickover:“Thebestengineersarethosewho,inadditiontotechnicalexpertise,havehadgoodtrainingintheliberalartsandunderstandtheworldaroundthem”。
简介:Energyandenvironmentalissueshavebecomeincreasinglyprominentinmattersoftransportation.Comparedwithroad,air,andseatransportation,railwaytransportationhastheadvantagesofalargetransmissioncapacity,withrapid,safe,andon-timetravel,requiringlesslandresources,withlowerenergyconsumption,lessenvironmentalpollution,andthecapacitytooperateundermostweatherconditions.Inparticular,high-speedrailwaytechnologyhasbeengrowingrapidly.Sincetheworld'sfirsthigh-speedrailwaywasbuiltinJapanin1964,morethantencountriesandregionshavedevelopedhigh-speedrailways,operatingoveratotalofmorethan10000km.High-speedrailwaysnotonlyprovidethepublicwithanewtypeofrapid,convenient,safe,andcomfortabletravel,butalsogreatlyboostthesocio-economicdevelopmentofthecountry.
简介:AlthoughtheimpactofroadtransportonurbanairqualityhasachievedahighprofileinChina,stillgreaterattentionisrequiredasithasnotyetbeenconsideredfullyeveninrelationtotheroadnetworklinkingcitiesandurbanareas.Strategicenvironmentalassessment(SEA)isasystematicandcomprehensiveprocessforevaluatingtheenvironmentalimpactsofapolicy,planorprograminpubliclyaccountabledecision-making.AirpollutionhasbeenrecognizedasasignificantissueinmosttransportSEApractices.TheStrategicEnvironmentalAssessmentoftheHubeiRoadNetworkPlan(2002-2020)(HRNP)wasintroducedasoneoftheWorldBank'spilotSEAprojects.Aneffectiveframeworkwasdevelopedtoinvestigatethefunctionalrelationshipbetweentheroadnetworkanditspotentialairpollutantemissions.Inthisstudy,twoindicatorswereidentified:emissionintensity/inventoryofpollutantsandthespatialdistributionofthemostpollutedareas.Becausestrategicactionsareinherentlynebulousanddataqualityisoftendisappointing,threealternativescenarioswereemployedtoaddressuncertaintiesanddata/scaleissues.Calculationsweremadeusingemissionmodelsandresultswereanalyzedwiththehelpofstatisticaltoolsandthegeographicinformationsystem(GIS).TheresultsfromtheprojectimplementationandthefeedbackfromtheWorldBankhavebothshownthattheproposedframeworkiseffectiveinthetransportSEAprocess.
简介:Toestablishthemechanismofsurfacechangeinacontinuouspolishingsystem,anidealmathematicalmodelisbuiltbasedonWinkler’shypothesisandthePrestonequation.Thebasicfeaturesofthemodelarethechangeratesinthesurfacepeak–valley(PV)valuesoftheworkpiece,conditioningdiskandpitchlap,ratherthanthespecificsurfaceshapes.Inaddition,anequilibriumstateexistsinthesystem,indicatingthatthesurfacechangeratesareallzero.Underequilibrium,thesurfaceofthelapcouldremainflat,anditisinsensitivetothesurfaceerroroftheworkpiece.Thesecharacteristicslaythetheoreticalfoundationsforhigh-efficiencyandhigh-precisionpolishing.Themethodstoobtainanequilibriumstatewithflatsurfacesarethenproposedandconfirmedexperimentally.High-precisionsurfacesbetterthanλ/10(λ=632.8nm)areconsistentlyproducedexperimentally.
简介:AimTheJournalsofZhejiangUniversitySCIENCE(A&B)areeditedbytheinternationalboardofdistinguishedChineseand
简介:在日常生活,人们经常在某些时期重复常规线路。在这篇论文,一个采矿系统被开发经过旅行发现个人的连续线路模式。数个人动人的地位的差异的无异状,采矿系统采用记录的适应GPS数据,五个数据过滤保证clean使数据犯错。采矿系统使用客户机/服务器体系结构保护个人隐私并且减少计算负担。服务者进行主要采矿过程,但是与到recover的不够的信息,真实个人发送。改进顺序的模式采矿的可伸缩性的无异状,一个新奇模式采矿算法,连续线路模式采矿(CRPM),被建议。这个算法能容忍在真实线路和摘录的不同骚乱经常的模式。基于九个人的旅行表演,那CRPM能更长多于twotimes提取的试验性的结果比传统的线路模式采矿算法发送模式。