外文参考资料及译文封面定稿.docx

外文参考资料及译文封面定稿.docx

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外文参考资料及译文封面定稿

毕业设计（论文）外文参考资料及译文

译文题目：

Telephoneexchangestheprincipleanddevelopment

　　　　　电话交换机的原理以及发展

学生姓名：

毛远学　　号：

0805110803

专　　业：

通信工程

所在学院：

信息技术学院

指导教师：

杨娟

职　　称：

讲师

2011年12月7日

说明：

要求学生结合毕业设计（论文）课题参阅一篇以上的外文资料，并翻译至少一万印刷符（或译出3千汉字）以上的译文。

译文原则上要求打印（如手写，一律用400字方格稿纸书写），连同学校提供的统一封面及英文原文装订，于毕业设计（论文）工作开始后2周内完成，作为成绩考核的一部分。

Telephoneexchangestheprincipleanddevelopment

From《BriefintroductionofSPCexchanges》

Abstract

theclassificationoftelephoneexchanges

1）telephoneexchangecontrolmodeisdividedintothefollowingtwocategoriesas:

1.Thewiringlogiccontrol2.Storageprogramcontrol

2）accordingtothepurposesofSPCexchangescanbedividedinto:

audiosignals,long-distanceandusersswitch;

3）intheairwaycanbedividedbytimeandswitches.

4）ofSPCexchangesbyinformationtransfermodecanbedividedinto:

analogswitchesanddigitalswitches.

Duetotheairinthenetworkprogram-controlledswitch（orexchangenetwork）inairseparationunitforwiring（orintersectionswitcharray）,andinthewordsofthegeneraltransferandwayoftheexchangeofanalogvoicesignalis,andhabitscalledprogram-controlledanalogswitches,theswitchtovoicethemoduleconversion（decoding）,theusercircuitissimple,andlowcost,mainlyusedasasmallcapacitysimulationusersswitch.

Atthegeneralinwordsprogram-controlledswitchpartwaytotransmitandswitchingisanalogvoicesignals,thushabitscalleddigitalprogram-controlledswitch,alongwiththedigitalcommunicationandpulsecodemodulation（PCM）technologytotherapiddevelopmentandapplicationof,theadvancedcountriesintheworldsincetheswithgreatpassiontodevelopingdigitalprogram-controlledswitch,throughhardwork,theFrenchfirstin1970inpullnyon（Lanion）successopenedtheworldthefirstdigitalprogram-controlledexchangesystemwas,itmarkedtheexchangetechnologyfromthetraditionalanalogexchangeintothedigitalageexchange.Becausedigitalprogram-controlledexchangetechnologyandequipmentoftheadvancednatureoftheeconomy,thetelephoneexchangegotintoanewstage,andtoopenthewordsbusiness,torealizecomprehensivedigitalswitchingbusinesslaidafoundation,thusithasbecomethemaindirectionofexchangetechnology,alongwiththemicroprocessortechnologyandspecialintegratedcircuitoftheleapdevelopment,digitalprogram-controlledexchangebecameapparentthesuperiorityoftheshow.AtpresenttheproductionoflargecapacityoftheChengKongJiallfordigital.

Second,theroleofprogram-controlledcustomerexchangersandtype

1.ThePBXrole

Usersswitchisindustrialandminingenterprises,andotherunitsinternalorgansofthetelephoneexchangeaspecialswitches,itsbasicfunctioniscompleteunitinterioruserscalleachother,butalsocanbeequippedwithtrunksinandoutofthepublictelephonenetworkaccessthenetspartandnetuserscall（includingcitycalls,domesticandinternationallong-distancecallslong-distance）.Becausethiskindofswitchesisspecialunitinterior,socanbebasedonuserneedstoincreasethenumberofadditionalperformancetoprovideconvenientuse.Sothiskindswitchhasagreaterflexibility.

Usersswitchonthetechnologyusedisthedevelopmenttrendofprogram-controlledcustomerexchangers,anewdigitalprogram-controlledswitchcanbeexchangedphoneusernotonlythebusiness,butalsocanexchangedataonthewordsbusiness,doavarietyofbusinessofcomprehensiveexchangeandtransmission.Foreachunitformintegratedservicesdigitalnetwork（ISDN）createdtheconditions.AtpresentalreadycanaccessISDNusers.SOPHOistheworldfirstcandealwithISDNbusinesscomprehensiveinformationswitches,whethertoprovideinterfaceorsignalingcompletelyaccordwiththestandardwayISDN.CanfirmlybelievesthatinthefuturetheISDNnetsindigitalprogram-controlledswitchwillusersplayanimportantrole.

2.Thetypeofprogram-controlledcustomerexchangers

Program-controlledcustomerexchangershavesomanykinds,fromatechnicalstructureisdividedintoprogram-controlledswitchandprogramcontrolairusersofdigitalsubscriberswitchestwokinds.Theformerisanalogvoicesignaltoexchange,belongstothesimulationexchangecategory.ThelatterexchangeofdigitalvoicesignalPCMis,isatypeofdigitalswitches.

Iffromtheuseofclassification,canbedividedintogeneralprogram-controlledcustomerexchangersandspecialprogram-controlledcustomerexchangerstwokindsbig.Universalusedingeneralenterprise,institution,factories,governmentagencies,andtheschooltovoicebusinessprimarilyoftheunit.Capacityinthegeneralhundredsofdoor,andtheinternaltrafficaccountsforabiggerchunkofthetotaltrafficthegeneralofaround70%.Thecurrentdomesticproductionofdoorofthe200program-controlledairseparationunitbelongtotheuserswitchthistype,itscharacteristicisthesystemstructureissimple,thevolumeissmall,easytouse,cheap,lessmaintenance.Specialapplytoallkindsofdifferentunits,accordingtoeachunitofspecialneedtoprovideallkindsofspecialfunction.Theseveralspecialseparatelyprogram-controlledcustomerexchangers:

Obviousshow.AtpresenttheproductionoflargecapacityoftheChengKongJiallfordigital.

AShakerChairandaLouisXVChair

TheShakerchairisapreciselycraftedbutunadornedobject.ItisamanifestationoftheconvictionsandvaluesoftheShakercommunity.Theseemphasisedsimplicity,arenunciationofworldlywealthandshow,andanavoidanceofthingswhichmightcauseprideandegotisticaltendencies.

BycontrasttheLouisXVchairexpressesopulence,statusandluxury.

AZenGardenandtheLasVegasStrip

TheZengardenisafocusformeditationandcontemplation.Itisanoutwardexpressionofaninnerjourney.

TheLasVegasStrip,bycontrast,couldbesaidtoepitomiseenticement,instantgratificationandgreed.

TheCitron2CVandtheRollsRoyce

TheCitron2CVisasmall,utilitariancarexpressiveofutilityandeconomy.Itishighlyversatile,relativelyinexpensiveandfulfilsitsfunctionwithoutluxuryorpretence.

TheRollsRoyceexpressesaverydifferentvaluesystem-oneconcernedwithpower,status,conspicuousconsumptionandluxury.Whileundoubtedlyahighqualityproduct,thisqualityismanifestedinawaywhichquiteexplicitlyspeaksofwealth,prideandvanity.

TheBicycleandtheMountain-Bike

Thebicycleisaproductwhichstartedoutasasimplestraightforwardmeansoftransport.Inmanyplacesitmaintainsthisroleasautilitarianobjectwhichfulfilsanimportantneed.Wherethebicycleisusedasabasicmeansoftransport,suchasinHollandandChina,itisaboutpersonaltransportationandlittleelse.

IncountriessuchasCanadaandtheUnitedStates,wherethecaristheprimarymodeoftransport,thebicycleis,forthemostpart,aleisureproduct,anditsmanifestationisthemountain-bike.IthasmovedfrombeingautilitarianproducttowhatLansleyhasreferredtoasa'positional'product1.Weacquire'positional'goods"notnecessarilyfortheirintrinsicworthbutaccordingtowhetherotherpeoplehavethem."2

HumanValuesandIncreasingWealth

Thetransitionfromanon-positionaltopositionalproductisanoutwardrepresentationofatransitionofvalues.Withincreasingwealthourvaluestendtochange,wemovefromusingbasic,functionalproductstodesiringandacquiringproductswhichhavemorestatus-orientedaccoutrementsandmeanings.Whilethishasalwaysbeenthecasethroughouthistory,inrecenttimestheabilitytoacquiresuchproductshasbecomepossibleforamuchlargerproportionofthepopulationthaninthepast.SinceWWIImoreandmoregoodshavemovedfrombeingneeds-oriented,to'positional'orstatus-oriented3.Thishascontributedtoanupwardspiralofconsumption,adownwardspiralintermsofenvironmentalstewardship,andawideninggapbetweenrichandpoor4.Moreover,thesedevelopmentsfundamentallyconflictwiththeperennialhumanvaluesespousedbythemajorreligiousandphilosophicaltraditions.

PerennialHumanValuesandContemporaryProducts

Allthemajorreligionsextolsimilarideasaboutthedangersofplacingtoomuchemphasisonpossessionsandmaterialwealth-anemphasisexacerbatedbyanincreasedorientationtowardsTpositionalUgoods.Indeed,theaspectswhichthesetraditionsvaluecouldbesaidtobetheantithesisorinverseofthosevaluesextolledbymodernpoliticalandbusinesspractices,andwhichmanycontemporaryproductsembodyandrepresent.

Gandhisaid:

"Iaskedmyselfwhatwasnecessaryformeinordertoremainabsolutelyuntouchedbyimmorality,byuntruth,bywhatisknownaspoliticalgain.....IcamedefinitelytotheconclusionthatifIhadtoservethepeopleinwhosemidstmylifewascastandwhosedifficultiesIwaswitnessfromdaytoday,Imustdiscardallwealth,allpossessions."5

Incontrasttothis,ourculturepromotestheveryoppositeview.Acquisitionofmaterialpossessionsisconstantlyencouragedbypoliticians,economistsandbusinessleaders:

"consumershavebeenonashoppingspreeforcars,furnitureandappliances,aswellashomes....TimO'Neill,chiefeconomistattheBankofMontreal,alsosaidthereturnofconsumerswhohavebeenhibernatingmostofthisdecadewillboosteconomicgrowth."6

"Wecanfeelgoodagain,sayTories.Thereturnofthe"feel-goodfactor"washailedbytheGovernmentyesterdayasfiguresshowedrenewedconfidenceinthehousingmarketandanincreasedpublicreadinesstospendoncredit.Ministerssaidthatthiswastheculminationofamonthofgoodeconomicnewsandvindicationoftheirpolicies."7

Peoplearecontinuallybeingtoldtoconsu