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127 个结果
  • 简介:ThetermhybridwarfarewasfirstcoinedbyUSmilitaryscholarsandlaterwidelyadoptedintheWesttorefertoRussianmilitaryoperationsintheUkrainianandSyriancrises.InRussia,itiscalled'Gerasimovism'.RussiaadaptedtheideaofhybridwarfareforitsmilitaryoperationsinUkraineandSyriaintoaRussian-stylehybridwarfarethathasseensuccessfulresultssofar.Thismodelislikelytoimpactfuturemilitarydevelopments.

  • 标签: 俄罗斯 混合 战争 风格 美国军事 军事行动
  • 简介:由生命周期评价(LCA)的申请方法论,这份报纸估计生产的环境影响和在中国在电的车辆使用的拖拉马达的处理。结果证明拖拉马达生产和处理的全部的精力使用,标准排出物和温室气体(GHG)排出物是大约2,899,MJ,4.5,kg并且259.5,kg每分别地交通。在调整排出物之中,SOx排放由全部的质量评价第一,由公司,PM10,没有x,PM2.5,和不稳定的有机化合物(VOC)列在后面。为大多数精力消费和排出物的马达材料生产阶段报道,由集会阶段和end-of-life处理列在后面舞台。在这研究,环境表演分析为材料生产阶段被扩大到在第二等的材料和主要材料的使用之间的比较。用100%,第二等的材料与百分之百主要的材料的使用相比在GHG排出物在精力消费,在调整排出物的49.8%减小,和49.3%减小导致52.9%减小,这被发现。

  • 标签: 生命周期评价 生产阶段 环境影响 牵引电机 温室气体排放量 出售
  • 简介:PROGRESSESOFTHESTUDYONIMPACTSOFCLIMATECHANGEONAGRICULTURALPRODUCTIONINCHINA¥WangFutang(王馥棠)PROGRESSESOFTHESTUDYONIMPACTSOFCLI...

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  • 简介:I.IntroductionofStudyAreaHaihebasincoversanareaof318000km2,consistingofHebeiProvince,BeijingandTianjin,municipalitiesandparto...

  • 标签: IMPACTS HUMAN activity WATER CYCLE Haihe
  • 简介:Aquaticvegetationplaysanimportantroleintheflowstructureofopenchannelsandthuschangesthefateandthetransportofsediment.Thisarticleproposesathree-dimensionalturbulencemodelbyintroducingvegetationdensityanddragforceintothecontrolequationsofwaterflowinthepresenceofvegetation.Themodelwasusedtocalculatetheimpactsofsubmergedvegetationontheverticalprofilesoflongitudinalflowvelocities,thechangesofthedepth-averagedflowvelocitiesinacompoundchannelwithemergentvegetationinthefloodplain,theremovalofsuspendedsedimentfromthechannelsbyemergentvegetation,andthebedchangesaroundandinavegetatedisland.Numericalinvestigationsshowthataquaticvegetationretardsflowinthevegetationzone,reducesthesedimenttransportcapacity,andcontributestoerosiononbothsidesofthevegetatedisland.Calculatedresultsagreewellwithexperimentalresults.

  • 标签: 湍流模型 水生植物 沉淀物 构造实验
  • 简介:TheimpactsofclimatechangeonChina'sagriculturearemeasuredbasedonRicardianmodel.Byusingcounty-levelcross-sectionaldataonagriculturalnetrevenue,climate,andothereconomicandgeographicaldatafor1275agriculture-dominatedcountiesintheperiodof1985-1991,wefindthatbothhighertemperatureandmoreprecipitationwillhaveoverallpositiveimpactonChina'sagriculture.However,theimpactsvaryseasonallyandregionally.Highertemperatureinallseasonsexceptspringincreasesagriculturalnetrevenuewhilemoreprecipitationisbeneficialinwinterbutisharmfulinsummer.Applyingthemodeltofiveclimatescenariosinthe2020sand2050sshowsthattheNorth,theNortheast,theNorthwest,andtheQinghai-TibetPlateauwouldalwaysbenefitfromclimatechangewhiletheSouthandtheSouthwestmaybenegativelyaffected.FortheEastandtheCentralChina,mostscenariosshowthattheymaybenefitfromclimatechange.Inconclusion,climatechangewouldbebeneficialtothewholeChina.

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  • 简介:Thesustainableuseofrenewableresourceshasbecomeanimportantissueworldwideinthemovetowardsalessfossil-fuel-intensivefuture.Mainstreammethodforfulfillingthisaimistoincreasetheshareofrenewableenergyandmaterialstosubstitutefossilfuelsandtobecomefullyindependentfromfossilfuelsoverthelong-term.However,theenvironmentalsustainabilityofthisendeavorhasbeenquestioned.Inaddition,economicandsocialsustainabilityissuesarealsomuchdebatedtopicsinthisparticularcontext.Forestresourcesareoftenthoughttocontributepartiallytoachievingaso-called'carbon-neutralsociety'.Inthisreview,wediscusssustainabilityissuesofusingforestbiomass.Wepresentseveralsustainabilityindicatorsforecological,economicandsocialdimensionsanddiscusstheissuesinapplyingtheminsustainabilityimpactassessments(SIAs).WealsopresentanumberoftoolsandmethodspreviouslyusedinconductingSIAs.WeapproachourstudyfromtheperspectiveoftheFinnishforestry;inaddition,variousaspectsregardingtheapplicationofSIAsinabroadercontextarealsopresented.Oneofthekeyconclusionsofthestudyisthatalthoughsufficientdataareavailabletomeasuremanyindicatorsaccurately,theimpactsmaybeverydifficulttoassess(e.g.impactofgreenhousegasesonbiodiversity)forconductingaholisticSIA.Furthermore,someindicators,suchas'biodiversity',aredifficulttoquantifyinthefirstplace.Therefore,amixofdifferentmethods,suchasMulti-criteriaAssessment,Life-cycleAssessmentorCost-BenefitAnalysis,aswellasdifferentapproaches(e.g.thresholdsandstrong/weaksustainability)areneededinaggregatingtheresultsoftheimpacts.SIAsareimportantinsupportingandimprovingtheacceptabilityofdecision-making,butacertaindegreeofuncertaintywillalwayshavetobetolerated.

  • 标签: 环境可持续性 生物经济 影响评估 森林资源 可持续发展问题 工具
  • 简介:Theimpactsofthethickness,thespecificacousticimpedanceandthemechanicallossfactorofthebackingontheperformanceofthethicknessmodepiezoelectrictransduceraresystemicallystudied,whicharefocusedontheeffectiveelectromechanicalcouplingcoefficientandthemechanicalqualityfactornearthecenterfrequency.Theresultsshowthatwithcontinuousincreasingofthebackingthickness,theeffectiveelectromechanicalcouplingcoefficientandthemechanicalqualityfactorarefoundrapidlydeclinedbyoscillationway.Withtheincreaseofthedifferencevalueoftheacousticimpedancebetweenthebackingmaterialandthepiezoelectricmaterial,theeffectiveelectromechanicalcouplingcoefficientdeceasesandthemechanicalqualityfactorincreases.Underconditionthatthethicknessofthepiezoelectricmaterialisfixed,theeffectiveelectromechanicalcouplingcoefficientisfounddeclinedwiththeincreaseofthemechanicallossfactorbymonotonousway.Themechanicalqualityfactorhasminimumvalueandtheelectriccharacteristiccurvetendstobesmoothinagivenfrequencyrange.Theequivalentcircuittheoryresultisingoodagreementwiththeonesbyfiniteelementmethodandtheexperimentalresults.Theworkmentionedaboveprovidesatheoreticalguidanceforthedesignandexperimentalfabricationofthethicknessmodepiezoelectrictransducer.

  • 标签: thickness MODE piezoelectric TRANSDUCER CHARACTERISTICS of
  • 简介:TheimpactoforbitalparametersontheclimateofChinaintheHoloceneissimulatedfrom11kaBPto0kaBPwithanintervalof1kausingNationalCenterforAtmosphericResearch(NCAR)CommunityAtmosphereModelversion2(CAM2).Thegeographicdistributionsofsummerprecipitationaroundboth9kaBPand4kaBPwererealisticallycapturedbyCAM2,comparedtotheproxydatacollectedfrom80stations.Amongallorbitalparameters,theprecessionplaysamajorroleincomputingsolarradiation,whichdominatesthevariationsofsummerprecipitationoverChinaduringtheHolocene.Thesummersaround9kaBPwerethewettestinChina.Lateron,theprecipitationgraduallyreducedtotheminimumaround0kaBPbyabout10%.ThistremendouschangeoccurredfromtheNortheastChinaandtheeasternInnerMongoliaextendingsouthwestwardstotheQinghai-TibetPlateau,especiallyovertheQinghai-TibetPlateau.

  • 标签: HOLOCENE 气候模拟 轨道的参数 气候湿度
  • 简介:SuburbanizationinlargecitiesisanimportantphenomenonintheprocessofurbanizationdevelopmentinChinainrecentdecades,whichplaysaveryimportantroleinpromotingcitydevelopment,whereassomesideeffectsontheeco-environmentappearedatthesametime.Thispaper,takingXi'anCityinChinaasacasestudysite,analyzedthefeaturesofpopulationsuburbanizationandindustrysuburbanizationandpointedouttheimpactsofsuburbanizationonurbaneco-environment.Basedontheresearch,suggestionsofcountermeasuresforurbanplanningandmunicipalmanagementofXi'anCityinprotectingurbaneco-environmentandconservingnaturalecologywereputforwardintheend.

  • 标签: 城市生态环境 城市郊区化 西安市 中国 工业郊区化 城市发展
  • 简介:AbstractAssisted reproductive technology (ART) has evolved rapidly over the last 40 years, offering hope to individuals and couples struggling with infertility. As technology continues to evolve, simulating a realistic female reproductive system environment has become a common goal for all types of ARTs, thereby reducing the impact of the artificial microenvironment on perinatal and offspring health. In this review, we provide a brief history of the development of each major ART and discuss the impact of ART on perinatal and offspring health. We also explore how the negative consequences of ART may be overcome and how its benefits can be maximized.

  • 标签: Assisted reproductive technology Perinatal outcomes Offspring health
  • 简介:AtthestartofournewJournalofBiosafety,IwaspromptedbymyCo-Editors-in-Chief,ProfessorWanandProfessorYou,toprovideregularreviewsorupdatesonbiosafetyforourreaders,giventhatImostlyresideoutsideChina,andhavemanyinternationalconnections.Thatisaverybigtask,andIwasnotsurethatIcoulddoitasthejournaldemands.However,Ihadthoughtthatinalighterway,IcouldattempttopresentmythoughtsonsomeissuesthatIfeelareofimportancetoday.Chinaisveryquicklyopeningtotheworld,economically,scientifically,andinmanyotherfields,andformanycolleaguesinsideandoutsideChina,thisisanewsituation.Duringmycareer,IhaveworkedinseveralcountriesofEurope,inNewZealand,andhadprojectsonothercontinents.Thisgavemeexperiencesindifferentpartsofourglobe,andIfeelthatallofus,ecologists,havetostartthinkingmorewidely,andbeawareofdevelopments,especiallyofhumanimpacts,onfarawayplaces.Somyviewwhenwritingtheseessayswilltrytobebothlocalandglobal.ThereforeIhavechosentheoveralltitleforthisseriesofessays'Thoughtsofatravellingecologist'.Belowyouwillbeabletoreadthefirstone-Ihopeyouwillenjoythem.Ifyoufeelliketoadd,orcommentonmyessays,pleasefeelfreetodoso.Anyfeedbackwillbemostwelcome.

  • 标签: 摘要 编辑部 编辑工作 读者
  • 简介:TheimportanceofsolvingtheemploymentproblemsbynongovernmentaleconomyinChinahasarousedtheconcernofmanyscholarswidely.However,fewliteraturescouldbefoundtodealwiththeimpactsonnonagriculturalemploymentgrowthinChinabynongovernmentaleconomyfromseverallevelssuchasthewholenation,urbanandrural.Basedontheresearchaccessedontherelationshipsbetweennongovernmentaleconomyandem-ployment,theimpactsofthedevelopmentofnongovernmentaleconomyonnon-agriculturalemploymentgrowthinChinaareemphasizedinthispaper.Takingtimeseriesdataofnon-agriculturalemploymentinChina’sdifferenteconomytypesin1992–2005asstudyobjects,byestablishingeconometricre-gressionmodels,somemeaningfulpointsarefoundasfollows,theimpactsofnongovernmentaleconomyonthenonagriculturalemploymentineithernationalorurban-rurallevelarerathersig-nificantalthoughtheirimpacts’degreesaredifferent.Basedontheresearchfindingsabove,somecountermeasuresareproposedtoacceleratethenongovernmentaleconomicdevelopmentandim-proveitsabilitytoabsorbnonagriculturalemployment.

  • 标签: 中国 非公有经济 非农业 雇工 增长
  • 简介:Two-dimensionalhydrodynamicsimulationfortheYangtzeEstuaryisperformedbyusingtheDelft3Dmodeladoptingtheshallowwaterequationsandthefinitevolumemethodonacurvilinearbody-fittedgrid.Themodeliscalibratedandvalidatedusingavailabletidaldataandfieldmeasurements.Thevelocityvectorfields,thetidallevels,thetrajectoriesofdroguesandthefarfieldsewagedilutionfromtheexistingandproposedoutfallsarestudiedforthespring/neaptideandthedry/wetseason.Theresultsshowthatthetidalcurrentsandtherunoffflowareabletodiluteanddispersethesewagefromtheoutfallstotheoutersea.ThesewagedilutioncontoursundervarioushydrodynamicconditionsindicatethatthedischargedeffluentatpresenthaverelativelyminorimpactonthewaterenvironmentoftheYangtzeEstuary;whereastheplannedsewageplanwouldsignificantlydeterioratethewaterqualityoftheestuaryintheabsenceofanytreatment,especiallyduringtheneaptideofdryseason.ThedroguetrackingshowsthattheeffluentfromthefourouffallswillbetransporteddownstreamtotheHangzhouBay.Astudyonthepollutionduetotheprojectandtheself-purificationcapacityofHangzhouBayisproposedinadditiontothatoftheYangtzeEstuary.

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  • 简介:PhasecompositeanalysesareconductedtoinvestigatethepossibleeffectoftheMadden–Julianoscillation(MJO)onthespringrainfallanomaliesinEastChinabyusingtheReal-timeMultivariateMJO(RMM)indexfromAustralianMeteorologicalBureau.Theresultsshowthattherainfallanomaliesoverthemid-andlower-valleyofYangtzeRiverarepositivewhentheMJOshiftseastwardtothemid-andeastern-IndianOcean,andanomalousprecipitationoverSouthChinaarepositivewhentheMJOmovesfurthereastwardtothemaritimecontinent,whereasspringrainfallanomaliesoverEastChinaarenegativeintheotherMJOepisodes.TheMJOimpactsontheprecipitationoverEastChinaresultfromthechangesinlarge-scaleatmosphericcirculationaswellasvorticityandwatervaportransportationinthemid-andlower-troposphere.

  • 标签: MJO activities spring precipitation over East
  • 简介:AspecialinterpolationprogramGREENhasbeendevelopedtodeterminetheclimaticparametersforthedistributionregionofChinesepine(PinustabulaeformisCarr.)basedontheresearchesonthedistributionofthetreespecies.Thecentralregion,whichisthemostsuitabledistributionregion,andpotentialdistributionregionofthespeciesundercurrentclimaticconditionsweremappedusingaGeographicInformationSystemIDRISI.Accordingtotheaveragedpredictionsby5GCMsfor2030,aprojecti...

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