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  • 简介:TheemergenceofZhangHeng’sseismoscopehasaprofoundhistoricalbackground.ThispaperintendstoexploretheformationandmaterialbasisofZhangHeng’sscientificthought.Itappearsthatthesimpleintentionof"observingvisionsanddistinguishinggoodfortuneormisfortune"washismotivationtodeveloptheseismoscope.Tracingitshistoricalbackground,theauthorsproposedinthispaperthatthedevelopmentofthisseismoscopestartedaround128A.D.,andbasedonperceptualknowledge,twoideasaboutearthquakescameintobeing,i.e.,earthquakelocationcouldbejudgedaccordingtotheinstrumentshakingdirection,andtheearthquakeandearthsplitwereessentiallydifferent.Intheinstrumentmanufacture,ZhangHengadvocatedaprincipleof"makingutensilstoimitatecosmos".Bythisprinciple,thefollowingthreeproblemswerereadilysolved:theseismoscopeimitatedtheresponseofthesuspensionsystemtoearthquakes(i.e.naturalseismoscope).Technically,thetriggermechanismofthelatchwasusedforreference,anditrecordedthephysicalevidenceofearthquakeoccurrencebyaningeniouswayofaballdroppingfromadragon’smouth.Thesolutionofthesethreekeyproblemsleadtotheemergenceoftheseismoscopein132A.D.andthesuccessfuldetectionofanearthquakein134A.D.Hisinventiondeepenedhumanity’sknowledgeofnaturallaws,andpromotedthedevelopmentofscienceandtechnologyinthattimeandlater.

  • 标签: 候风地动仪 张衡 地震定位 科学思想 仪器制造 物质基础
  • 简介:<正>ThearticlemainlyexploresthecurrentconceptofWorldEnglishesanditsimplicationforlanguageteaching.AfterthehistoryandpresentdefinitionofWorldEnglisheshavebeendiscussedinabroadperspective,theauthorcontinuestotalkabouttheinfluenceofWorldEnglishesonWorldLanguageEducation.ChineseEnglisheducationisthenspecificallyaddressedwithimplicationsgivenforbothpolicy-makersandclassroomteachersofEnglish.

  • 标签: World Englishes STANDARD ENGLISH CHINESE ENGLISH
  • 简介:Thispaperdiscussespointwiseerrorestimatesfortheapproximationbyboundedlinearoperatorsofcontinuousfunctionsdefinedoncompactmetricspaces(X,d),Theauthorsintroduceanewmajorautofthemodulusofthecontinuitywhichisthesrnallestamongthoseg(ξ)'swhichhavethefollowingpropertiesω(f,ε)≤9(f,ε)andg(f,λε)≤(1+λ)g(f,ε)andbythismajorantanewquantitativeKorovkintypetheoremonanycompactmetricspaceisproved.

  • 标签: 最小支配连续模 数值近似 紧空间 有界线性算子
  • 简介:Eachcomponentofthehumanearperformsaspecificfunctioninhearing.Theactualprocessofsoundtransductiontakesplaceintheauditoryportionoftheinnerear,thefluid-filledcochlea.Inthecochlea,thesensitivityandefficiencyofsensoryapparatustoconvertmechanicalenergyintoneuralactivity,largelydependsonthefluidicandionicenvironment.Inthelateralwallofcochlea,thesecretoryepitheliumstriavascularisplaysanimportantroleinthemaintenanceoffluidicandionichomeostasis.Avarietyofgenemutationsdisturbsthecochlearhomeostasisandsubsequentlyleadstohearingimpairment.Thereviewcoversseveralaspectsofcochlearhomeostasis,fromcochlearfluidandthefunctionalroleofstriavascularis,cochlearK+recyclinganditsmolecularsubstratestogeneticdeafnesswithabnormalcochlearhomeostasis.

  • 标签: HOMEOSTASIS mechanical energy maintenance molecular inner
  • 简介:多字的表情(MWE)在自然语言经常并且不合语法地出现。在免费文章识别MWE是一个很挑战性的问题。这份报纸建议没有知识、无指导、语言无关的多字的表示距离(MED)。新度量标准从一个接受物理原则被导出,从n克测量距离到它的语义,并且超过在二应用的MWE上的另外的最先进的方法:问答和命名实体抽取。

  • 标签: 应用程序 度量 语义距离 自然语言 物理原理 命名实体
  • 简介:第一原则的计算被执行学习有TiC的形态学的硼和它的关系的吸附。尽管所有低索引的TiC水晶飞机上的硼的吸附是热地有利的,它将更容易被吸附由,这被发现终止C{111}并且{011}飞机,当时不太可能被吸附由{001}。B-B簇的形成的学习显示硼adatoms在上的分发终止C(111)并且{011}飞机将是更一致的,并且adatom的散开进一步证实上述结果。根据几何学关系和不同水晶飞机的生长率,TiC上的硼的吸附将严重阻碍生长,这被推出{111}并且{011}飞机,它能让TiC长成六角形的血小板。

  • 标签: TIC 吸附 表面和接口 第一原则的计算
  • 简介:TheestablishmentoftheEAEUwillhavebroadstrategicimplicationsfortheEurasiancontinentandtheworld.IthashelpedRussiaconsolidateitssphereofinfluenceinthepost-Sovietspaceandstrengtheneditsroleasapoleintheworld.ItwillalsoexertawideinfluenceontheEurasianregionaleconomicstructure,thegeographicaleconomiccompetitionbetweenRussiaandtheWest,andthirdparties’influenceintheregion.

  • 标签: 联盟 世界 经济 吉尔吉斯斯坦 白俄罗斯 哈萨克斯坦
  • 简介:Thispaperaimsatprovidinganuncertainbilevelknapsackproblem(UBKP)model,whichisatypeofBKPsinvolvinguncertainvariables.AndthenanuncertainsolutionfortheUBKPisproposedbydefiningPENashequilibriumandPEStackelbergNashequilibrium.Inordertoimprovethecomputationalefficiencyoftheuncertainsolution,severaloperators(binarycodingdistance,inversionoperator,explosionoperatorandbinarybacklearningoperator)areappliedtothebasicfireworksalgorithmtodesignthebinarybackwardfireworksalgorithm(BBFWA),whichhasagoodperformanceinsolvingtheBKP.Asanillustration,acasestudyoftheUBKPmodelandthePEuncertainsolutionisappliedtoanarmamentstransportationproblem.

  • 标签: uncertainty bilevel PROGRAMMING KNAPSACK problem BINARY
  • 简介:当一个非免疫学的机关首先从事了新陈代谢的、滋养的存储和detoxification活动,人的肝通常被察觉。然而,我们现在知道健康的肝也是复杂免疫学的一个地点活动象非造血的房间人口一样由一个多样的有免疫力的房间全部剧目调停了。在疾病得非的肝,新陈代谢并且织物改变功能要求发炎的元素。在有到饮食、微生物引起的产品的常规暴露的联合,这发炎为过多的有免疫力的激活创造潜力。在这复杂微型环境,肝的免疫系统容忍无害的分子当同时对可能的传染代理人仍然保持警惕时,恶意的房间或纸巾损坏。在到由病原体或织物损坏的挑战的适当有免疫力的激活之上,解决发炎的机制是必要的维持肝动态平衡。清除‘的失败;dangerous’;刺激或调整适当地激活的有免疫力的机制导致病理学的发炎和纤维变性,肝硬化和最终的肝失败的进步发展描绘的破坏织物动态平衡。肝的煽动性的机制因此在健康的成年的肝有角色的一个系列;他们是必要的维持织物和机关动态平衡并且dysregulated,肝病理的关键司机与长期的感染,autoimmunity和恶意被联系。在这评论,我们在正常的肝动态平衡探索发炎和煽动性的调停人的变化感觉并且求婚作为一条治疗学的途径肝特定的有免疫力的规定小径指向治疗肝疾病。

  • 标签: 肝脏疾病 炎症介质 免疫学 稳态 自身免疫性疾病 组织损伤
  • 简介:Thisinvestigationdiscussesfurthertheextenttowhichanewdamagetheoryrecentlyproposedbytheauthorcanserveasaunifiedtheorytocharacter-izevariousductilefailureproblems.Ageneraldamageintegralandcorrespondingcriterionforductilefracturearepresented.Anewparameterforductilefractureisemphasized,whichisexperimentallyverifiedasamaterialconstantindependentofstressstate,hasclearphysicalmeaning,andcaneasilybedetermined.Theapplica-bilityofthistheorytoevaluationoftheductilityofweldsandengineeringmaterialsundervariousconditionsisexamined.Also,itisusedtopredicttheeffectofresid-ualstressonfailureofwelds,topredictsheetforminglimits,andtocorrelatethevariabilityofelasto-plasticfracturetoughnessvaluesJ1candδcwithdifferentspec-imengeometries.Anewconstraintcorrectionmethodisproposed,andconstraintcorrectednewtoughnessparametersJdcandδdcarerecommended.Experimentshaveshownthatthetoughnessvariationwithdifferentspecimengeometriescanef-fectivelyberemovedbyuseofthemethod.Thegeneralapplicabilityofthetheorytocharacterizationofvariousductilefailuresprovidesanewdesigntoolforengineeringcomponentsorstructures.

  • 标签: DUCTILE FRACTURE DAMAGE DAMAGE MECHANICS FRACTURE
  • 简介:Usingtime-dependentcompressiblelaminarNavier-Stokesequationswithafinitevolumemethodincorporatingathird-order-accuratediscretizationscheme,theflowstructuresaroundaslenderatcertainincidencesarenumericalsimulatedandtypicalcrossflowpatternsarepresented.Atincidence10°,thesevorticalconfigurationsaredifferentatdissimilaraxiallocationsthoughtheyaresymmetric.At35°,thesymmetricvorticalstructuresstillmaintainovertheslender,yettheirinteractionatafterbodyisintensethanthatattheforebodysincethetwovorticeshavefullydevelopeddownstream.Theunstabletopologicalstructureoftrajectoryofsaddle-to-saddlepointsandmultiplelimitcyclearefurtherdiscussedintopologicalstabilitytheory.Thesestructureseasilyproducebifurcationwithperturbation.Theresultssupporttheviewofhydrodynamicinstabilityofvorticesflowfield.

  • 标签: 对称涡流 拓扑稳定性 数字模仿 交叉流程 分歧理论
  • 简介:Onthebasesofthepropertiesofabstracthierarchicalstructuremodelandtheconcretestructureofthemodelsystem,whichisconvenienttosolvepracticalproblems,avisualinteractivehierarchicalcoordinationmethodhasbeenproposed.Inthispaper,acompensationadjustmentsub-modelforhydropowerstations,anoptimaloperationsub-modelforhydro-thermalpowersystems,andanaggregationmodelbasedontheaspirationleveltheoryarebuilt,andthesemodelscanbesolvedwithdecisionsupportalgorithm.Thesetofobjectivesanditsstructurecouldbemadebythedecision-makerinvisualsoftware,whichcouldbedecidedbyAHP.Finally,theapplicationresultsshowthatthismethodologyisfeasible,however,thesoftware(DSS)needsfurtherimprovement.

  • 标签: INTERACTIVE DECISION support algorithm MULTI-OBJECTIVE and
  • 简介:Inthispaper,theauthorsintroducemedicinalvesiculationtherapyfromitsorigin,pointsforattentioninclinicalapplication,andtheirindividualexperiences.Inclinicalapplication,theauthorsadvocate:①avoidusingdrugsthatareover-irritatingintheproperty,andstrictlycontrollingthedoseofdrugsendthedurationofapplication,②)inselectionofdrugs,somefactorsaspatients'conditions,theseason,thegeographiclocation,etc.shouldbetakenintoaccount.Inthepresentpaper,3typicalcasesofbronchialasthma,tonsilswellingandfacialparalysistreatedwithmedicinalvesiculationtherapyareintroduced.Clinicalpracticedemonsetratesthatthistherapyiseconomical,simpleandconvenientandfairlyeffectiveintreatmentofsomechronicdiseases.

  • 标签: 针灸疗法 冷针 临床应用 面部瘫痪 扁桃体肿大 支气管哮喘
  • 简介:TheheightoftheU.S.strengthisattheperiodfromPresidentClinton'scomingtopowerin1992tilltheendofthelarge-scalebattlesintheIraqwaronMay1,2003.HowAmerica'snationalfortunewilldevelopdependsonhowAmericawillresolvetheIraqissue,implementitsprogramofreformingMiddleEast,andmaintaininsteadofdamagingitsnationalfundamentalprinciplesathome.

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