简介：TravelingtoBeijingforthefirsttime?Don'tgetcaughtin,out,orupbyculturalshocks.Knowhowthingsshould-andshouldn't-hedonetoensureyourtripisamemorableoneforalltherightreasons.

简介：Carbon-manganesesteelisoftenappliedincomponentsofpipesinnuclearplant.Ultrasonicfatiguetestsfollowinglowcyclefatigue(LCF)cyclesdamagedareusedtostudythestrengthofveryhighcyclefatigure(VHCF).ThecomparisonoftestresultsofsimpleVHCFandcumulativefatigue(LCFplusVHCF)showsthatLCFloadinfluencesthefollowingVHCFstrength.ContinuumdamagemechanicsmodelisextendedtoVHCFregion.TheeffectofLCFloadonVHCFisstudiedbyanimprovedcumulativedamagemodel.

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简介：Chlorofluorocarbons(CFCs)orhydrochlorofluorocarbons(HCFCs)areasmainrefrigerantsusedintraditionalrefrigerationsystemsdrivenbyelectricityfromburningfossilfuels,whichisregardedasoneofthemajorreasonsforozonedepletion(man-maderefrigerantsemission)andglobalwarming(CO2emission).Sopeoplepaymoreandmoreattentiontonaturalrefrigerantsandenergysavingtechnologies.AninnovativesystemcombiningCO2transcriticalcyclewithejectorcycleisproposedinthispaper.TheCO2compressionsub-cycleispoweredbyelectricitywiththecharacteristicsofrelativelyhightemperatureinthegascooler(definedasanintercoolerbytheproposedsystem).Inordertorecoverthewasteheat,anejectorsub-cycleoperatingwiththenaturalrefrigerants(NH3,H2O)isemployed.Thetwosub-cyclesareconnectedbyanintercooler.Thiscombinedcyclejoinstheadvantagesofthetwocyclestogetherandeliminatesthedisadvantages.TheinfluencesoftheevaporationtemperatureinCO2compressionsub-cycle,theevaporationtemperatureintheejectorsub-cycle,thetemperatureintheintercoolerandthecondensationtemperatureintheproposedsystemperformancearediscussedtheoreticallyinthisstudy.Inaddition,someuniquefeaturesofthesystemarepresented.

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简介：Intheapplicationsofaircrafts,automobiles,railways,biomedicineandoff-shorestructures,manycomponentsmayexperiencecyclicloadingconditionsoveralongperiodoftime,runninguptoseveralhundredmillioncycles.1Determinationoflonglifefatiguebehaviorbecomesextremelyimportantforbetterunderstandinganddesignofcomponentsandstructures.

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简介：ThedirectedmotionofaBrownianparticleinaflashingpotentialwithvarioustransitionprobabilitiesandwaitingtimesinoneoftwostatesisstudied.AnexpressionfortheaveragecycleperiodisproposedandthesteadycurrentJoftheparticleiscalculatedviaLangevinsimulation.Theresultsshowthattheoptimalcycleperiodrm,whichtakesthemaximumofJ,isshiftedtoasmallvaluewhenthetransitionprobabilityλfromthepotentialontothepotentialoffdecreases,themaximalcurrentappearsinthecaseoftheaveragewaitingtimeinthepotentialonbeinglongerthaninthepotentialoff,andthedirectionofcurrentdependsontheratiooftheaveragetimeswaitingintwostates.

简介：Inrecentyears,lifecycleassessment(LCA)methodiswidelyusedingreenmanufacturing,energysaving,andemissionreductionofironandsteelproduction.BasedonthecarbonsteelLCAresearchandrelevantstandardsathomeandabroad,theapplicationofLCAinstainlesssteelinBaosteelwasstudied.Throughthestudyofstainlesssteel'sgoalandscope,lifecycleinventory,LCAandinterpretation,knowledgeandexperienceofLCA'sapplicationinstainlesssteelwasobtained.

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.

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简介：Wepresentasufficientandnecessaryconditionforaso-calledCnkpatterntohavepositivesemidefnite(PSD)completion.SincethegraphoftheCnkpatterniscomposedbysomesimplecycles,ourresultsextendthosegivenin[1]forasimplecycle.WealsoderivesomeresultsforapartialToeplitzPSDmatrixspecifyingtheCnkpatterntohavePSDcompletionandToeplitzPSDcompletion.

简介：Thispaper,firstpreparedanddeliveredforaworkshoponteachingBiblicalWisdomLiteratureinChina,providesmewiththeopportunity,sotospeak,"tokilltwobirdswithonestone."NotonlywillIcommentonthemainthemeofthe

简介：TheperformancesofnonlinearWDMsystemswithdifferentdutycyclearecomparedbymeansofnumericalsimulation.Thenumericalresultsshowthattheopticalpulsewithdutycycleof0.5issuperiortotheconventionalNRZmodulationschene.Theconclusionisdifferentfromthatofsomereferences.Thereasonisthatintersymbolinterferenceisnotincludedinsomereferences.Infact,intersymbolinterferenceplaysanimportantroleinmonlinearWDMsystem.Althoughthelargerthedutycycleis,thestrongertheeffectofthecross-phasemodulationandself-phasemodulationonnonlinearWDMishowever,thelargerthedutycycleis,thestrongertheintersymbolinterferenceis.

简介：Forestshavemultiplebenefitsandfunctions,includingmitigationofclimatechange.Theimpactsofforestsontheglobalcarboncycleincludeforestsascarbonsinks,wood-basedproductsascarbonsinks,bio-energy,andproductionanduseofnon-timberproducts.Inthepastdecades,forestcoverofChinahasincreasedfrom8.6%to18.21%bylarge-scaleafforestationandconversionofcroplandintoforests.Forestbiomasscarbon(C)stockincreasedfrom4.3PgC(1PgC=1015gC)intheearly1980sto5...

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简介：Thefatiguelifeofnumerousaerospace,locomotive,automotiveandbiomedicalstructuresmaygobeyond10~8cycles.Determinationoflonglifefatiguebehaviorbecomesextremelyimportantforbetterunderstandinganddesignofthecomponentsandstructures.Initially,beforetheinventionofultrasonicfatiguetesting,mostoftheengineeringmaterialsweresupposedtoexhibitfatiguelifeupto10~7cyclesorless.Thispaperreviewscurrentunderstandingofsomefundamentalaspectsonthedevelopmentofacceleratedfatiguetestingmethodanditsapplicationinultra-highcyclefatigue,crackinitiationandgrowthmechanismsofinternalfracture,S-Ndiagram,fatiguelimitandlifeprediction,etc.