简介：Inthispaper,anunderwaterstructureismodeledasacylindricalshellwithinternalbulkheads,andclosedbyatruncatedconicalshell,anditconsistsofmetalsubstrateandsoundabsorbingcoating,whoseFGMcoreisconsidered.Supposetheinnercavityandouterspaceofthestructurearefilledwithairandfluidmediums,themechanicalresponseoftheunderwaterstructureiscalculatedwithGalerkinmethodwhiletheacousticresponseisinvestigatedbymeansoftheHelmholtzintegral.Somenumericalexamplesaregivenandtheeffectofgeometricalsizeandmaterialparametersonmechanicalandacousticresponseisdiscussed.

简介：Theeffectivenessofmechanicalventilation,bothinvasive(byendotrachealintubation)andnon-invasiive(bynegativepressureventilation)wasestablishedduringtheepidemicsofpolioinEuropeandNorthAmericainthelain1950sandearly1960s.Theindicationsforventilationhaveincreasedsincethattime,andinvasiveventilationserviceshavebecomeconcentratedinhighly-staffedcriticalcareunitsand.insomepartsofEurope,respiratorycareunits.

简介：ＯＮＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＹＯＦＣＯＮＳＴＲＡＩＮＴＷｅｉＹａｎｇ（韦杨）；ＬｉａｎｇＬｉｆｕ（梁立孚）；ＬｉａｎｇＺｈｏｎｇｗｅｉ（梁忠伟）（ＲｅｃｅｉｖｅｄＳｅｐ．６，１９９４；ＣｏｍｍｕｎｉｃａｔｅｄｂｙＣｈｉｅｎＷｅｉｚａｎｇ）Ａ...

简介：Aporosity-freeandcontamination-freesurfacelayerwithgrainsizesrangingfromnanometertomicrometerinFesampleswasobtainedbysurfacemechanicalattritiontreatment(SMAT)technique.MechanicalandwearpropertiesofthesurfacelayerintheSMATedandannealedFesamplesweremeasuredbymeansofnanoindentationandnanoscratchtests,respectively.ExperimentalresultsshowedthatthehardnessofthesurfacelayerintheSMATedFesampleincreasedevidentlyduetothegrainrefinement.TheelasticnoduliofthesurfacelayersintheSMATedandannealedFesampleswereunchanged,independentofgrainsizeinthepresentgrainsizeregime.ComparedwiththeoriginalFesample,thewearresistanceenhancedandthecoefficientoffrictiondecreasedinthesurfacelayeroftheSMATedFesample.

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简介：ＡＣＯＭＰＵＴＥＲＭＵＬＴＩＭＥＤＩＡＢＯＯＫＯＦＭＥＣＨＡＮＩＣＡＬＤＲＡＷＩＮＧＺｕｏＺｏｎｇｙｉＦｅｎｇＫａｉｐｉｎｇＡｂｓｔｒａｃｔＴｈｉｓｒｅｐｏｒｔｇｉｖｅｓａｖｉｅｗｏｆａｃｏｍｐｕｔｅｒｍｕｌｔｉｍｅｄｉａｂｏｏｋｏｆｍｅｃｈａｎｉｃ...

简介：Combinedwithpracticalcase,thepaperelaboratesthedevelopmentandapplicationsofmechanicaldrawing,mechanicaldesignandmanufacturingbasedonSolidworkssoftware.Bycombiningprofessionalcoursesbetweeneachother,theknowledgecontinuouslythroughdifferentcoursescanenhancestudents'enthusiasmforthecourseandmakemorereasonablearrangementforthecourses.

简介：Non-invasiveventilation(NIV)istheprovisionofventilatorysupportwithoutinstrumentationoftheairway.Itcanbeachievedusinganegative-pressuremachine(e.g.‘ironlung')or,morecommonly,withpositivepressureadministeredthroughawell-fittingmask.Thiscontributionconsiderspositivepressureventilationonly;negativepressureisnowseldomused.

简介：Theturtleshellisanamazingstructureoptimizedthroughthelong-termevolutionbynature.Thispaperreportstheexperimentalstudyonthemechanicalpropertyatdifferentlevelsandlocations,andthemicrostructureoftheshellfromTrachemysscripta(Red-earturtle)livinginSouthChina.

简介：Biomaterialssuchasbone,teeth,nacreandsilkareknowntohavesuperiormechanicalpropertiesduetotheirspecificnanocompositestructures.Herewereportthatthewoodpecker’stongueexhibitsanovelstrengthandflexibilityduetoitsspecialcompositemicro/nanostructure.Thetongueconsistsofaflexiblecartilage-and-boneskeletoncoveredwithathinlayertissueofhighstrengthandelasticity.Attheinterfacebetweenthecartilage-and-boneskeletonandthetissuelayer,thereisahierarchicalfiber-typedconnection.Itisthisspecialdesignofthetonguethatmakesthewoodpeckersefficientincatchingtheinsectsinsidetrees.Thespecialmicro/nanostructuresofthewoodpecker’stongueshowusapotentialmethodtoenhancetheinterfacialconnectionbetweensoftandhardmateriallayersforbio-inspiredcompositesystemdesigns.

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简介：Plantleafisanaturalcompositebiomaterial,anditsstrengthiscloselyrelatedtothemicrostructure.Inthispaper,themechanicalcharacteristicsofeightspeciesofplantleaveswereinvestigatedandanalyzed.Theultimatestrengthofleavesandthehardnessofleafsurfacesweremeasuredbyusinguniversaltestingmachineandnanoindentertester,respectively.Thetensilestrengthoftheparallelmicrostructurewasinvestigatedbasedonitscross-sectionalmechanicalmodel.Theresultsoftensiontestsindicatethattheultimatestrengthofaleafisrelatedtothematerialcompositionandstructure.Thecoriaceousleavesusuallyexhibithighertensilestrength.Forexample,thePhyllostachyspubescensleafcanachievethemaximumultimatestrengthof5.9091N·mm-2.Itisconcludedfromtheresultsofhardnessteststhatmaterialcomponentsofleafsurfacecaninfluencethesurfacehardnessevidently.Theleafsurfacecomposedofmoreligninandcellulosematerialsshowsahighersurfacehardnessthanthatcomposedofmorecarbohydratesmaterials.

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简介：Recently,opticaltechniqueshaveattractedgreatattentionduetotheirexcellentnon-destructive,non-contact,high-resolution,andfull-fieldcharacteristics.Applicationscanbefoundindiversefieldssuchasprecisionmechanicsandmanufacturing,aerospaceandautomotivetestingandinspection,materialsscience,and

简介：Manymoderncontrolapplicationsareinterdisciplinaryinnature.Varietyofdisciplinesareorientedonapplicationofcontroltheoryandmodelingofmechanical/biomechanicalsystemstosolvepracticalproblemsintheirspecificfields.Bearingthisinmind,thereareincludedinthisspecialsubjectsomeinterestingcontributionscoveringdifferentareassuchasbifurcationsandchaosindynamicalsystems,stabilityofdynamicalsystems,originalnumericalmethodsofvibrationanalysis,non-smoothsystems,engineeringsystemsanddifferentialequations,controlindynamicalsystems,asymptoticmethodsinnonlineardynamics,vibrationsoflumpedandcontinuoussystems,dynamicsinlifesciencesandbioengineering.

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简介：随城市里的国内煤气的消费和在中国的镇的增加，煤气的爆炸事故相当经常发生了，并且许多结构极大地被损坏。合理物理设计能保护结构免受被破坏的伤害，但是爆炸负担的字符一定由建立一个正确机械模型模仿发泄的煤气的爆炸第一是有学问的。爆炸过程向化学工业设备的安全被学习许多年了。这些研究的关键问题通常是方程包含了必须被试验性的数据评估的一些可调节的参数，并且计算的过程是极其复杂的，因此这些研究的可靠性严重被限制。把研究基于这些，一个简单数学模型被使用发泄方程的精力保存，集体保存，煤气的州的方程，绝热压缩方程和气体在这篇论文建立。爆炸负担必须被考虑房间布局估计；压力上升的率然后被使用一个骚乱因素改正，因此压力时间曲线能被获得。由使用这个方法，复杂计算被避免，当试验性、计算的结果相当适合很好时。一个典型矩形的房间里的一些压力时间曲线被计算在爆炸压力上调查不同点火地点，煤气的厚度，集中，房间尺寸和发泄的区域的影响。结果显示了那：当在这个房间的几何学中心被点燃时，它是最危险的条件；更大燃烧速度，更坏的发泄效果；越大发泄的压力，越higher山峰压力；越大发泄的区域，越多降低山峰压力。

简介：MostofKBEsystemsappliedbypreviousresearchersaredependentonsomeCADsoftware,whichmakesknowledgehardtobereusedtootherCADsoftware.IndependentknowledgebasedsystemisindependentofCADsoftware;thereforeknowledgecanbereusedfreely.Thispaperdescribesindependentknowledgebasedsystemformechanicaldesign.Adetaileddiscussionabouttypicaldesignisputforwardincludingdesignprocessimplementationbasedonknowledgeengineering,independentknowledgebaseddesignarchitecture.Themainprincipalofknowledgedrivenengineeringisexplained.TheimplementationofKBEonthedesignofwormreducerisstudiedasacase.Independentknowledgebasedreducerdesignsystemisrealized.TheusageofindependentknowledgebasedsystemmakesKBEsystemworkindependentofCADsoftware,whichenhancestheirportabilityandfertilizesthecollaborativeworkofheterogeneousCADsystems.