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1MechanicalEngineeringIntroductiontoMechanicalEngineeringMechanicalengineeringisthebranchofengineeringthatdealswithmachinesandtheproductionofpower.Itisparticularlyconcernedwithforcesandmotion.HistoryofMechanicalEngineeringTheinventionofthesteamengineinthelatterpartofthe18thcentury,providingakeysourceofpowerfortheIndustrialRevolution,gaveanenormousimpetustothedevelopmentofmachineryofalltypes.Asaresultanewmajorclassificationofengineering,separatefromcivilengineeringanddealingwithtoolsandmachines,developed,receivingformalrecognitionin1847inthefoundingoftheInstitutionofMechanicalEngineersinBirmingham,England.Mechanicalengineeringhasevolvedfromthepracticebythemechanicofanartbasedlargelyontrialanderrortotheapplicationbytheprofessionalengineerofthescientificmethodinresearch,design,andproduction.Thedemandforincreasedefficiency,inthewidestsense,iscontinuallyraisingthequalityofworkexpectedfromamechanicalengineerandrequiringofhimahigherdegreeofeducationandtraining.NotonlymustmachinesrunmoreeconomicallybutcapitalCostsalsomustbeminimized.FieldsofMechanicalEngineeringDevelopmentofmachinesfortheproductionofgoodsthehighmaterialstandardoflivinginthedevelopedcountriesowesmuchtothemachinerymadepossiblebymechanicalengineering.Themechanicalengineercontinuallyinventsmachinestoproducegoodsanddevelopsmachinetoolsofincreasingaccuracyandcomplexitytobuildthemachines.Theprincipallinesofdevelopmentofmachineryhavebeenanincreaseinthespeedofoperationtoobtainhighratesofproduction,improvementinaccuracytoobtainqualityandeconomyintheproduct,andminimizationofoperatingcosts.Thesethreerequirementshaveledtotheevolutionofcomplexcontrolsystems.Themostsuccessfulproductionmachineryisthatinwhichthemechanicaldesignofthemachineiscloselyintegratedwiththecontrolsystem,whetherthelatterismechanicalorelectricalinnature.Amoderntransferline(conveyor)forthemanufactureofautomobileenginesisagoodexampleofthemechanizationofacomplexseriesofmanufacturingprocesses.Developmentsareinhandtoautomateproductionmachineryfurther,usingcomputerstostoreandprocessthevastamountofdatarequiredformanufacturingavarietyofcomponentswithasmallnumberofversatilemachinetools.Oneaimisacompletelyautomatedmachineshopforbatchproduction,operatingonathreeshiftbasisbutattendedbyastaffforonlyoneshiftperday.DevelopmentofmachinesfortheproductionofpowerProductionmachinerypresupposeanamplesupplyofpower.Thesteamengineprovidedthefirstpracticalmeansofgeneratingpowerfromheattoaugmenttheoldsourcesofpowerfrommuscle,wind,andwaterOneofthefirstchallengestothenewprofessionofmechanicalengineeringwastoincrease2thermalefficienciesandpower;thiswasdoneprincipallybythedevelopmentofthesteamturbineandassociatedlargesteamboilers.The20thcenturyhaswitnessedacontinuedrapidgrowthinthepoweroutputofturbinesfordrivingelectricgenerators,togetherwithasteadyincreaseinthermalefficiencyandreductionincapitalcostperkilowattoflargepowerstations.Finally,mechanicalengineersacquiredtheresourceofnuclearenergy,whoseapplicationhasdemandedanexceptionalstandardofreliabilityandsafetyinvolvingthesolutionofentirelynewproblems-Thecontrolsystemsoflargepowerplankandcompletenuclearpowerstationshavebecomehighlysophisticatednetworksofelectronic,fluidic.Electric,hydraulic,andmechanicalcomponents,ailoftheseinvolvingmeprovinceofthemechanicalengineer.Themechanicalengineerisalsoresponsibleforthemuchsmallerinternalcombustionengines,bothreciprocating(gasolineanddiesel)androtary(gas-turbineandWankel)engines,withtheirwidespreadtransportapplications-Inthetransportationfieldgenerally,inairandspaceaswellasonlandandsea.themechanicalengineerhascreatedtheequipmentandthepowerplant,collaboratingincreasinglywiththeelectricalengineer,especiallyinthedevelopmentofsuitablecontrolsystems.DevelopmentofmilitaryweaponsTheskillsappliedtowarbythemechanicalengineeraresimilartothoserequiredincivilianapplications,thoughthepurposeistoenhancedestructivepowerratherthantoraisecreativeefficiency.Thedemandsofwarhavechanneledhugeresourcesintotechnicalfields,however,andledtodevelopmentsthathaveprofoundbenefitsinpeace.Jetaircraftandnuclearreactorsarenotableexamples.BiaengineeringBioengineeringisarelativelynewanddistinctfieldofmechanicalengineeringthatincludestheprovisionofmachinestoreplaceoraugmentthefunctionsofthehumanbodyandofequipmentforuseinmedicaltreatment.Artificiallimbshavebeendevelopedincorporatingsuchlifelikefunctionsaspoweredmotionandtouchfeedback.Developmentisrapidinthedirectionofartificialspare-partsurgery.Sophisticatedheart-lungmachinesandsimilarequipmentpermitoperationsofincreasingcomplexityandpermitthevitalfunctionsinseriouslyinjuredordiseasedpatientstobemaintained.EnvironmentalcontrolSomeoftheearliesteffortsofmechanicalengineerswereaimedatcontrollingman'senvironmentbypumpingwatertodrainorirrigatelandandbyventilatingmines.Theubiquitousrefrigeratingandair-conditioningplantsofthemodemagearebasedonareversedheatengine,wherethesupplyofpowerpumpsheatfromthecoldregiontothewarmerexterior.Manyoftheproductsofmechanicalengineering,togetherwithtechnologicaldevelopmentsinotherfields,havesi