簡(jiǎn)介：附錄1BEGINNINGASPNET20INCASPACTIVESERVERPAGESISARELATIVELYNEWTECHNOLOGYTHAT’SALREADYLEAPTTHROUGHSEVERALSTAGESOFEVOLUTIONITWASINTRODUCEDABOUTSEVENYEARSAGOASANEASYWAYTOADDDYNAMICCONTENTTOORDINARYWEBPAGESSINCETHEN,IT’SGROWNINTOSOMETHINGMUCHMOREAMBITIOUSAPLATFORMFORCREATINGADVANCEDWEBAPPLICATIONS,INCLUDINGECOMMERCESHOPS,DATADRIVENPORTALSITES,ANDJUSTABOUTANYTHINGELSEYOUCANFINDONTHEINTERNETASPNET20ISTHELATESTVERSIONOFASP,ANDITREPRESENTSTHEMOSTDRAMATICCHANGEYETWITHASPNET,DEVELOPERSNOLONGERNEEDTOPASTETOGETHERAJUMBLEOFHTMLANDSCRIPTCODEINORDERTOPROGRAMTHEWEBINSTEAD,YOUCANCREATEFULLSCALEWEBAPPLICATIONSUSINGNOTHINGBUTCODEANDADESIGNTOOLSUCHASVISUALSTUDIO2005THECOSTOFALLTHISINNOVATIONISTHELEARNINGCURVENOTONLYDOYOUNEEDTOLEARNHOWTOUSEANADVANCEDDESIGNTOOLVISUALSTUDIOANDATOOLKITOFOBJECTSTHENETFRAMEWORK,YOUALSONEEDTOMASTERAPROGRAMMINGLANGUAGESUCHASCTHEINTERNETBEGANINTHELATE1960SASANEXPERIMENTITSGOALWASTOCREATEATRULYRESILIENTINFORMATIONNETWORKONETHATCOULDWITHSTANDTHELOSSOFSEVERALCOMPUTERSWITHOUTPREVENTINGTHEOTHERSFROMCOMMUNICATINGDRIVENBYPOTENTIALDISASTERSCENARIOSSUCHASNUCLEARATTACK,THEUSDEPARTMENTOFDEFENSEPROVIDEDTHEINITIALFUNDINGTHEEARLYINTERNETWASMOSTLYLIMITEDTOEDUCATIONALINSTITUTIONSANDDEFENSECONTRACTORSITFLOURISHEDASATOOLFORACADEMICCOLLABORATION,ALLOWINGRESEARCHERSACROSSTHEGLOBETOSHAREINFORMATIONINTHEEARLY1990S,MODEMSWERECREATEDTHATCOULDWORKOVEREXISTINGPHONELINES,ANDTHEINTERNETBEGANTOOPENUPTOCOMMERCIALUSERSIN1993,THEFIRSTHTMLBROWSERWASCREATED,ANDTHEINTERNETREVOLUTIONBEGANITWOULDBEDIFFICULTTODESCRIBEEARLYWEBSITESASWEBAPPLICATIONSINSTEAD,THEFIRSTGENERATIONOFWEBSITESOFTENLOOKEDMORELIKEBROCHURES,CONSISTINGMOSTLYOFFIXEDHTMLPAGESTHATNEEDEDTOBEUPDATEDBYHANDBASICHTMLPAGEISALITTLELIKEAWORDPROCESSINGDOCUMENTITCONTAINSFORMATTEDCONTENTTHATCANBEDISPLAYEDONYOURCOMPUTER,BUTITDOESN’TACTUALLYDOANYTHINGTHEFOLLOWINGEXAMPLESHOWSHTMLATITSSIMPLEST,WITHADOCUMENTTHATCONTAINSAHEADINGANDSINGLELINEOFTEXTANHTMLDOCUMENTHASTWOTYPESOFCONTENTTHETEXTANDTHETAGSTHATTELLTHEBROWSERHOWTOFORMATITTHETAGSAREEASILYRECOGNIZABLE,BECAUSETHEYOCCURINSIDEANGLEDBRACKETSHTMLDEFINESTAGSFORDIFFERENTLEVELSOFHEADINGS,PARAGRAPHS,HYPERLINKS,ITALICANDBOLDFORMATTING,HORIZONTALLINES,ANDSOONFOREXAMPLE,SOMETEXTTELLSTHEBROWSERTODISPLAYSOMETEXTINTHEHEADING1STYLE,WHICHUSESALARGE,BOLDFONTFIGURE11SHOWSTHESIMPLEHTMLPAGEINABROWSERHTML20INTRODUCEDTHEFIRSTSEEDOFWEBPROGRAMMINGWITHATECHNOLOGYCALLEDHTMLFORMSHTMLFORMSEXPANDHTMLSOTHATITINCLUDESNOTONLYFORMATTINGTAGSBUTALSOTAGSFORGRAPHICALWIDGETS,ORCONTROLSTHESECONTROLSINCLUDECOMMONINGREDIENTSSUCHASDROPDOWNLISTS,TEXTBOXES,ANDBUTTONSHERE’SASAMPLEWEBPAGECREATEDWITHHTMLFORMCONTROLSHTMLFORMSALLOWWEBAPPLICATIONDEVELOPERSTODESIGNSTANDARDINPUTPAGESWHENTHEUSERCLICKSTHEERRORPRONEDEPLOYMENTSTEPSINSTEAD,AWEBAPPLICATIONCANBEUSEDONANYCOMPUTERTHATHASINTERNETACCESSBUTWHENDEVELOPERSUSECLIENTSIDETECHNOLOGIES,THEYENCOUNTERAFEWFAMILIARHEADACHESSUDDENLY,CROSSBROWSERCOMPATIBILITYBECOMESAPROBLEMDEVELOPERSAREFORCEDTOTESTTHEIRWEBSITESWITHDIFFERNETOPERATINGSYSTEMSANDBROWSERS,ANDTHEYMIGHTEVENNEEDTODISTRIBUTEBROWSERUPDATESTOTHEIRCLIENTSINOTHERWORDS,THECLIENTSIDEMODELSACRIFICESSOMEOFTHEMOSTIMPORTANTBENEFITSOFWEBDEVELOPMENTORTHATREASON,ASPNETISDESIGNEDASASERVERSIDETECHNOLOGYALLASPNETCODEEXECUTESONTHESERVERWHENTHECODEISFINISHEDEXECUTING,THEUSERRECEIVESANORDINARYHTMLPAGE,WHICHCANBEVIEWEDINANYBROWSERFIGURE13SHOWSTHEDIFFERENCEBETWEENTHESERVERSIDEANDCLIENTSIDEMODELTHESEARESOMEOTHERREASONSFORAVOIDINGCLIENTSIDEPROGRAMMINGISOLATIONCLIENTSIDECODECAN’TACCESSSERVERSIDERESOURCESFOREXAMPLE,ACLIENTSIDEAPPLICATIONHASNOEASYWAYTOREADAFILEORINTERACTWITHADATABASEONTHESERVERATLEASTNOTWITHOUTRUNNINGINTOPROBLEMSWITHSECURITYANDBROWSERCOMPATIBILITYSECURITYENDUSERSCANVIEWCLIENTSIDECODEANDONCEMALICIOUSUSERSUNDERSTANDHOWANAPPLICATIONWORKS,THEYCANOFTENTAMPERWITHITMECASES,ASPNETALLOWSYOUTOCOMBINETHEBESTOFCLIENTSIDEPROGRAMMINGWITHSERVERSIDEPROGRAMMINGFOREXAMPLE,THEBESTASPNETCONTROLSCANINTELLIGENTLYDETECTTHEFEATURESOFTHECLIENTBROWSERIFTHEBROWSERSUPPORTSJAVASCRIPT,THESECONTROLSWILLRETURNAWEBPAGETHATINCORPORATESJAVASCRIPTFORARICHER,MORERESPONSIVEUSERINTERFACEHOWEVER,NOMATTERWHATTHECAPABILITIESOFTHEBROWSER,YOURCODEISALWAYSEXECUTEDONTHESERVERSTATELIMITATIONSTOENSUREOPTIMUMPERFORMANCE,THEWEBISBUILTONSTATELESSPROTOCOLS,WHICHMEANSASSOONASAPAGEISSENTTOAUSER,THECONNECTIONISCLOSEDANDANYUSERSPECIFICINFORMATIONISDISCARDEDASPINCLUDESASESSIONSTATEFEATURETHATALLOWSPROGRAMMERSTOWORKAROUNDTHISPROBLEMUSINGSESSIONSTATE,AWEBAPPLICATIONCANRETAINTEMPORARYINFORMATIONABOUTEACHCLIENTINSERVERMEMORYHOWEVER,SESSIONSTATEISUSELESSINSCENARIOSWHEREAWEBSITEISHOSTEDBYSEVERALSEPARATEWEBSERVERSINTHISSCENARIO,ACLIENTMIGHTACCESSSERVERBWHILEITSSESSIONINFORMATIONISTRAPPEDONSERVERAANDESSENTIALLYABANDONEDASPNETCORRECTSTHISPROBLEMBYALLOWINGSTATETOBESTOREDINACENTRALREPOSITORY,SUCHASASEPARATEPROCESSORADATABASETHATALLSERVERSCANACCESSASPNETDEALSWITHTHESEPROBLEMSANDMANYMOREBYINTRODUCINGACOMPLETELYNEWMODELFORWEBPAGESTHISMODELISBASEDONAREMARKABLEPIECEOFTECHNOLOGYCALLEDTHENETFRAMEWORKYOUSHOULDUNDERSTANDTHATTHENETFRAMEWORKISREALLYACLUSTEROFSEVERALTEC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簡(jiǎn)介：1外文原文外文原文THECDESIGNRATIONALECISDESIGNEDTOBEANEXTENSIBLEPLATFORMFORRAPIDLYDEVELOPINGPROGRAMANALYSISTOOLSSEVERALFEATURESOFCFACILITATETHISBYCONVENTION,CWRITTENINLOWERCASELETTERSREFERSJUSTTOTHEPROGRAMTHATABSTRACTSDATAFROMACPROGRAMCIAWRITTENINCAPITALLETTERSREFERSTOTHESYSTEMMADEOFTHATABSTRACTORANDALLOFTHETOOLSTHATUSETHEDATABASEITGENERATESENTITIESINCLUDELES,MACROS,TYPES,FUNCTIONSANDVARIABLESSEPARATIONOFINFORMATIONEXTRACTIONANDPRESENTATIONTHEPROCESSOFEXTRACTINGINFORMATIONFROMAPROGRAMANDTHEPROCESSOFPRESENTINGTHATINFORMATIONSHOULDBESEPARATETHISELIMINATESTHENEEDFOREACHCANALYSISTOOLTODUPLICATETHEPARSINGPROCESSANDALLOWSCTOOLSTOSHARETHEINFORMATIONANDPRESENTITINDIFFERENTWAYSASIMILARDOCTRINEWASDEVELOPEDINTHEINTERLISPPROJECTUNFORTUNATELY,MANYCANDCTOOLSTODAYSTILLVIOLATETHISBASICPRINCIPLEAWELLCONCEIVEDCONCEPTUALMODELACONCEPTUALMODELBASEDONTHEENTITYRELATIONSHIPMODELWASDESIGNEDTODESCRIBETHEENTITIES,ATTRIBUTES,ANDRELATIONSHIPSINCPROGRAMSTHEMODELSERVESASANACCURATEHIGHLEVELSPECIFICATIONFORTHECONTENTSOFTHEPROGRAMDATABASERELATIONALDATABASETOSUPPORTREUSE,CSTORESABSTRACTEDINFORMATIONINTHEFORMOFARELATIONALDATABASETHISMAKESITPOSSIBLEFORTHATINFORMATIONTOBEACCESSEDBYAWIDEVARIETYOFEXISTINGDATABASEQUERYSYSTEMSINCREMENTALDATABASECONSTRUCTIONCBUILDSANDMAINTAINSAPROGRAMDATABASEFORLARGESYSTEMSEFFICIENTLYBECAUSEITALLOWSINCREMENTALUPDATESOFADATABASEWHENASETOFCSOURCELESISUPDATED,ONLYTHATPORTIONHASTOBEREABSTRACTEDTOUPDATETHEDATABASETHESEBASICDESIGNPRINCIPLESGIVETOOLSBASEDONCANADVANTAGEOVERMANYTRADITIONALDEVELOPMENTTOOLS,WHICHUSUALLYMERGETHEINFORMATIONEXTRACTIONAND3OFTHESIGNALREFLECTEDBYTHETARGET,ISADIRECTMEASUREOFTHEDISTANCEDTOBEMEASUREDHOWEVER,THELASERSIGNALISTRANSMITTEDATTHESPEEDOFLIGHTTHEREFORE,APRECISERANGINGREQUIRES,ACHANGEINTHEDISTANCETOTARGETBYFIFTEENCENTIMETERCORRESPONDSTOACHANGEINTIMEDIFFERENCEOFONLYONENANOSECONDINTHEPRIORART，THEREARESOMEMETHODSTOTRANSFORMTHEMEASUREDVALUESINORDERTOOBTAINTHEREQUIREDTIMERESOLUTIONANDCALCULATETHETIMEOFFLIGHTTHESEMETHODS,EITHERSTRETCHORTRANSFORMITINTOANOTHERMEASURABLEVALUESUCHASAVOLTAGE,RELYONAGREATQUANTITYOFPRECISEELECTRONICCOMPONENTS,INCREASETHECOMPLEXITYOFTHECIRCUITTHEACCURACYOFTHESEMETHODSISEASILYDEGRADEDBYTEMPERATUREAFFECTSMETHODSOFCALCULATINGTHEPHASEDIFFERENTBETWEENTHEELECTRONICCIRCUITMORECOMPLICATEDANDTAKEALONGERTIMETOPERFORMGENERALLY,ASPECIFICRANGINGMETHODANDAPPARATUSLIMITSTHERANGEANDRESOLUTIONOBTAINABLETHEREWITHTHATMEANS,ITISALMOSTIMPOSSIBLETOCHANGETHEMBYJUSTMODIFYINGAPARTOFTHECIRCUITOBJECTORIENTATIONANDCCISJUSTONEOFMANYPROGRAMMINGLANGUAGESINUSETODAYWHYARETHERESOMANYLANGUAGESWHYDONEWONESAPPEAREVERYFEWYEARSPROGRAMMINGLANGUAGESHAVEEVOLVEDTOHELPPROGRAMMERSEASETHETRANSITIONFROMDESIGNTOIMPLEMENTATIONTHEFIRSTPROGRAMMINGLANGUAGESWEREVERYDEPENDENTONTHEUNDERLYINGMACHINEARCHITECTUREWRITINGPROGRAMSATTHISLEVELOFDETAILISVERYCUMBERSOMEJUSTASHARDWAREENGINEERSLEARNEDHOWTOBUILDCOMPUTERSYSTEMSOUTOFOTHERCOMPONENTS,LANGUAGEDESIGNERSALSOREALIZEDTHATPROGRAMSCOULDBEWRITTENATAMUCHHIGHERLEVEL,THEREBYSHIELDINGTHEPROGRAMMERFROMTHEDETAILSOFTHEUNDERLYINGMACHINEWHYARETHERESUCHALARGENUMBEROFHIGHLEVELPROGRAMMINGLANGUAGESTHEREARELANGUAGESFORACCESSINGLARGEINVENTORYDATABASES,FORMATTINGFINANCIALREPORTS,CONTROLLINGROBOTSONTHEFACTORYFLOOR,PROCESSINGLISTS,CONTROLLINGSATELLITESINREALTIME,SIMULATINGANUCLEARREACTOR,PREDICTINGCHANGINGATMOSPHERICCONDITIONS,PLAYINGCHESS,ANDDRAWINGCIRCUITBOARDSEACHOFTHESEPROBLEMSREQUIRESDIFFERENTSETSOFDATASTRUCTURESAND

簡(jiǎn)介：內(nèi)蒙古科技大學(xué)本科生畢業(yè)設(shè)計(jì)說(shuō)明書（畢業(yè)論文）題目基于AT89C51單片機(jī)的步進(jìn)電機(jī)控制系統(tǒng)學(xué)生姓名學(xué)號(hào)專業(yè)自動(dòng)化班級(jí)自動(dòng)化063班指導(dǎo)教師內(nèi)蒙古科技大學(xué)畢業(yè)設(shè)計(jì)說(shuō)明書（畢業(yè)論文）IIBASEDONAT89C51SINGLECHIPCOMPUTERSTEPPINGMOTORCONTROLSYSTEMABSTRACTSTEPPINGMOTORISAKINDOFDIGITALCONTROLSYSTEMCOMPONENTSITCANACHIEVEQUICKSTARTUP,POSITIVEINVERSION,STOPPINGANDSPEEDCONTROL,ACCORDINGTOTHECONTROLPULSEITHASHIGHPRECISIONSTEPANGLE,ANDCANBESELFLOCKINGWHENITKEEPSSTILLASTHESECHARACTERISTICS,STEPPINGMOTORINAUTOMATICCONTROLSYSTEM,ESPECIALLYINTHEOPENLOOPCONTROLSYSTEMHASBEENWIDELYAPPLIEDTHISARTICLEMAINLYFOCUSESONTAKINGSINGLECHIPCOMPUTERANDCYCLEPULSEDISTRIBUTORASTHECORE,ANDDESIGNINGTHESTEPPINGMOTORCONTROLSYSTEMTHROUGHTHEDESIGNOFTHESOFTWAREANDHARDWAREDEBUGGING,ITREALIZESCONTROLLINGTHESTEPMOTOR’SACCELERATIONANDDECELERATIONAUTOMATICALLY,ACCORDINGTOPARAMETERSETTINGMAKINGTHESYSTEMARRIVETHEENDPOINTWITHTHESHORTESTTIME,BUTNOTOCCUROUTINGOFSTEPBESIDESITCANACCURATELYACHIEVESTARTUP,POSITIVEINVERSIONANDSHUTDOWNHARDWARETAKESAT89C51ASTHECOREOFCONTROLCIRCUIT,MAINLYINCLUDINGCYCLEPULSEDISTRIBUTOR,KEYBOARDANDDISPLAYCIRCUIT,STEPPINGMOTORDRIVINGCIRCUIT,ETCSOFTWAREPARTADOPTSTHECLANGUAGEPROGRAMMING,MAINLYINCLUDINGKEYBOARDANDDISPLAYPROGRAM,STEPPINGMOTORSPEEDCONTROLPROGRAM,STOPJUDGINGPROGRAM,ETCKEYWORDSSTEPPINGMOTORCONTROLSYSTEMSPEEDCONTROLSINGLECHIPCOMPUTER

簡(jiǎn)介：外文翻譯1附錄附錄A英文原文英文原文DESIGNOFPWMCONTROLLERINAMCS51COMPATIBLEMCUAUTHORYUELIHU,WEIWANGMICROELECTRONICRESEARCHDEVELOPMENTCENTERCAMPUSPOB221,149YANCHANGRD,SHANGHAI200072,CHINAINTRODUCTIONPWMTECHNOLOGYISAKINDOFVOLTAGEREGULATIONMETHODBYCONTROLLINGTHESWITCHFREQUENCYOFDCPOWERWITHFIXEDVOLTAGETOMODIFYTHETWOENDVOLTAGEOFLOADTHISTECHNOLOGYCANBEUSEDFORAVARIETYOFAPPLICATIONSINCLUDINGMOTORCONTROL,TEMPERATURECONTROLANDPRESSURECONTROLANDSOONINTHEMOTORCONTROLSYSTEMSHOWNASFIG1,THROUGHADJUSTINGTHEDUTYCYCLEOFPOWERSWITCH,THESPEEDOFMOTORCANBECONTROLLEDASSHOWNINFIG2,UNDERTHECONTROLOFPWMSIGNAL,THEAVERAGEOFVOLTAGETHATCONTROLSTHESPEEDOFMOTORCHANGESWITHDUTYCYCLEDT1/TINTHISFIGURE,THUSTHEMOTORSPEEDCANBEINCREASEDWHENMOTORPOWERTURNON,DECREASEDWHENPOWERTURNOFFFIG1THERELATIONSHIPBETWEENVOLTAGEOFARMATUREANDFIG2ARCHITECTUREOFPWMMODULETHEREFORE,THEMOTORSPEEDCANBECONTROLLEDWITHREGULARLYADJUSTINGTHETIMEOFTURNONANDTURNOFFTHEREARETHREEMETHODSCOULDACHIEVETHEADJUSTMENTOFDUTYCYCLE1ADJUSTFREQUENCYWITHFIXEDPULSEWIDTH2ADJUSTBOTHFREQUENCYANDPULSEWIDTH3ADJUSTPULSEWIDTHWITHFIXEDFREQUENCYGENERALLY,THEREAREFOURMETHODSTOGENERATETHEPWMSIGNALSASTHEFOLLOWING1GENERATEDBYTHEDEVICECOMPOSEDOFSEPARATELOGICCOMPONENTSTHISMETHODISTHEORIGINALMETHODWHICHNOWHASBEENDISCARDED2GENERATEDBYSOFTWARETHISMETHODNEEDCPUTO外文翻譯3DUTYCYCLEUPDATESARECONFIGURABLETOBEIMMEDIATEDORSYNCHRONIZEDTOTHEPWMFIG3ARCHITECTUREOFPWMMODULEDETAILSOFTHEARCHITECTUREPMWGENERATORTHEARCHITECTUREOFTHE2OUTPUTPWMGENERATORSHOWNINFIG4ISBASEDONA16BITRESOLUTIONCOUNTERWHICHCREATESAPULSEWIDTHMODULATEDSIGNALTHESYSTEMISSYNTHESIZEDBYASYSTEMCLOCKSIGNALWHOSEFREQUENCYCANBEDIVIDEDBY4TIMESOR12TIMESTHROUGHSETTINGTHEVALUEOFT3MFORPWM0ORT4MFORPWM1INTHESPECIALREGISTERPWMCONASSHOWNINFIG4TOPWM0GENERATOR,THECLOCKTO16BITCOUNTERWILLBEPREDIVIDEDBY4TIMESBYDEFAULTWHENT3MISSETTOZEROANDTHECLOCKWILLBEDIVIDEDBY12TIMESWHENT3MISSETTO1THISISALSOTRUEFORPWM1THEOTHERBITSINPWMCONAREEXPLAINEDINDETAILINTABLE1FIG4BITMAPPINGOFPWMCON

簡(jiǎn)介：武漢工業(yè)學(xué)院武漢工業(yè)學(xué)院畢業(yè)設(shè)計(jì)（論計(jì)（論文）文）設(shè)計(jì)（論文）題目設(shè)計(jì)（論文）題目基于基于DSPDSP的語(yǔ)音信號(hào)的去噪方法的語(yǔ)音信號(hào)的去噪方法姓名________李YI__________YI__________學(xué)號(hào)___090000000____________090000000_________院（系）院（系）_電氣與電子工程學(xué)院電氣與電子工程學(xué)院______專業(yè)______通信工程通信工程______________________指導(dǎo)教師指導(dǎo)教師_____00000_____________00000________20132013年5月5日2目錄摘要基于DSP的語(yǔ)音信號(hào)的去噪方法1目錄2第一章緒論31．1課題的研究背景及意義31．2語(yǔ)音去噪的基礎(chǔ)知識(shí)41．2．1語(yǔ)音信號(hào)的特點(diǎn)41．2．2噪聲特性41．3TIDSP介紹5131C54X芯片614CCS開發(fā)環(huán)境6141CCS集成開發(fā)環(huán)境715本文重點(diǎn)總結(jié)8第二章小波在語(yǔ)音消噪中的應(yīng)用921經(jīng)典的小波算法9211模極大值去噪算法9212相關(guān)性去噪算法9213小波閾值去噪算法1022一種新的小波閾值去噪方法1123本章總結(jié)12第三章實(shí)驗(yàn)設(shè)計(jì)原理及過(guò)程1331小波去噪原理分析13311小波去噪原理13312小波去噪步驟1432閾值的選取與量化14321軟閾值和硬閾值14322閾值的幾種形式15323閥值的選取1633實(shí)驗(yàn)步驟16331小波去噪驗(yàn)證仿真16332小波去噪與FFT去噪效果對(duì)比1734本章總結(jié)18第四章實(shí)驗(yàn)仿真及圖1941實(shí)驗(yàn)結(jié)論19結(jié)論21致謝22參考文獻(xiàn)23附錄24

簡(jiǎn)介：中文中文4220字畢業(yè)論文外文資料翻畢業(yè)論文外文資料翻譯題目合成ΒMO2C薄膜和電子場(chǎng)發(fā)射13我們目的是用價(jià)格低廉的材料替代鉑族金屬來(lái)表面氫分離。這種材料合成的薄膜將有利于催化劑性能的基礎(chǔ)研究。許多技術(shù)已被用于沉積碳化鉬薄膜，包括化學(xué)氣相沉積（CVD），814，物理氣相沉積（PVD），9，11和電化學(xué)沉積。15MOC是相當(dāng)復(fù)雜的，它有眾多的穩(wěn)定和亞穩(wěn)化合物和晶相。1416，相純度的控制一直是個(gè)難題，CVD和PVD兩種方法的制備中，薄膜通常包含混合富含碳的產(chǎn)物，它是一個(gè)復(fù)雜的依賴具體操作條件選測(cè)的過(guò)程。8，11，14與此相反，它的催化應(yīng)用制備所需的粉末狀ΒMO2C相。14，后來(lái)BOUDART和他的同事12開發(fā)出一種方法，加入H2稀釋的碳?xì)浠衔锊⒉捎贸绦蛏郎胤磻?yīng)或TPR的混合物轉(zhuǎn)換成高表面積MO2C密集的氧化鉬粉。MOO3轉(zhuǎn)變?yōu)镸O2C方法涉及MOO3的晶格中的氧碳替代，在反應(yīng)過(guò)程中有MO原子的微小位移。因?yàn)镸O2C的摩爾體積比MOO3的摩爾體積小，微孔狀的氧化物轉(zhuǎn)換成碳化物。在適當(dāng)條件下的氧化鉬被轉(zhuǎn)換成MO2C過(guò)程中沒(méi)有形成金屬鉬作為反應(yīng)中間體。金屬燒結(jié)，避免使用這種方法，在物催化劑催化劑條件下，它可以準(zhǔn)備具有很高的表面積（5090平方米/克）。REBROVETAL5采用這方法，形成催化劑通過(guò)預(yù)氧化的鉬片滲碳涂料把它們應(yīng)用到水煤氣變換反應(yīng)。本實(shí)驗(yàn)是合成純相的ΒMO2C未來(lái)研究模型催化劑層薄膜。下面我們介紹一個(gè)兩步合成方法。首先，采用等離子體增強(qiáng)化學(xué)氣相沉積法（PECVD）在MOF6/H2/O2混合物中使密集的氧化鉬薄膜沉積在硅片上。MOF6在這種化學(xué)反應(yīng)中是很獨(dú)特，以前的含鉬的化合物的反應(yīng)是用MO（CO）的1718或MOCL514，19來(lái)化學(xué)氣相沉積。用PECVD參數(shù)來(lái)描述氧化物的增長(zhǎng)速度和質(zhì)量。使用的PECVD形成氧化物將產(chǎn)生在更廣泛的承印物上。薄膜通過(guò)TPR的催化條件轉(zhuǎn)化為ΒMO2C相。使用一套分析技術(shù)可將整個(gè)過(guò)程中膜的組成和結(jié)構(gòu)的演變進(jìn)行了量化。2試驗(yàn)一氧化氮合成在MOF6/H2/O2混合在一個(gè)電容耦合的PECVD系統(tǒng)中使氧化鉬薄膜沉積。采用類似PECVD反應(yīng)的化學(xué)的方法，用類似的氣體混合物（WF6/H2/O2）17，20已成功地應(yīng)用于合成的電致變色WO3的薄膜。鉬六氟化硫ACROSORGANIC,995VOL的分解容易，但是反應(yīng)過(guò)程中產(chǎn)生的氟自由基蝕刻膜是可逆的。為了解決這一問(wèn)題，我們添加了氫的高頻電子流來(lái)除去氟原子形成。還提供氧氣過(guò)量，以形成充分的氧化膜。這里描述的所有方法是在常溫下進(jìn)行的，并且電壓固定在200W。使用校準(zhǔn)的針閥控制MOF6生成，而電子質(zhì)量流量控制器控制氧氣和氫氣流速。該反應(yīng)的沉積壓力范圍為500?700毫托取決于機(jī)械泵（愛(ài)德華茲，E2M40）的控制。

簡(jiǎn)介：中文中文43754375字出處出處SCHAFERRW,RABINERLRDESIGNOFDIGITALFILTERBANKSFORSPEECHANALYSISJBELLSYSTEMTECHNICALJOURNAL,1971,501030973115實(shí)現(xiàn)語(yǔ)音分析的數(shù)字濾波器組設(shè)計(jì)RWSCHAFERANDLRRABINERBELLTELEPHONELABORATORIES,INCORPERATEDMURRYAYHILL,NJ本文是關(guān)于數(shù)字濾波器組的設(shè)計(jì)和分析，這些濾波器組是由相同帶通特性的等間隔帶通濾波器組成。通過(guò)選擇合適的相關(guān)相位的帶通濾波器，合成濾波器的響應(yīng)特性得到顯著提升。這個(gè)結(jié)果擴(kuò)展了一般濾波器的功能。I引言許多語(yǔ)音處理系統(tǒng)是基于短時(shí)頻譜分析的概念。這些系統(tǒng)的頻譜分析儀通常是由一組具有合適頻率范圍的混合通帶的帶通濾波器組組成。連續(xù)時(shí)間濾波的濾波器組往往被用在語(yǔ)音分析上，現(xiàn)在基于數(shù)字硬件實(shí)現(xiàn)的數(shù)字濾波器組也是可用的。在數(shù)字濾波器組的設(shè)計(jì)方面，其提供了很多優(yōu)點(diǎn)，這些優(yōu)點(diǎn)包括單個(gè)帶通濾波器設(shè)計(jì)的靈活性，實(shí)現(xiàn)的精確性，數(shù)字硬件的穩(wěn)定性，通過(guò)數(shù)字硬件的復(fù)用實(shí)現(xiàn)濾波器組應(yīng)用的高效性。此外，由數(shù)字帶通濾波器組成的濾波器組的設(shè)計(jì)技術(shù)也值得考慮。為了專注于濾波器組的設(shè)計(jì)的基礎(chǔ)概念，定義一個(gè)理想濾波器組的頻譜分析儀是很有用的。（圖1）描述了一個(gè)這樣的濾波器組，II均勻?yàn)V波器組的分析假定圖1的帶通濾波器有以下形式的脈沖響應(yīng)（1）其中，這里的K1,HNT是原型低通濾波器的脈沖響應(yīng)，（K01?W時(shí)濾波器被使用）這組帶通濾波器的功能是公式（2）中的Z用取代后，獲得這些濾波器的頻率響應(yīng)E?JΩT如果原型低通濾波器的頻率響應(yīng)急劇，從公式（3）中可以得到

簡(jiǎn)介：中文中文3580字畢業(yè)設(shè)計(jì)（論計(jì)（論文）外文）外文參考資料及譯文譯文題目譯文題目基于語(yǔ)音識(shí)別的智能門控系統(tǒng)設(shè)計(jì)出處出處2009ISECSINTERNATIONALCOLLOQUIUMONCOMPUTING,COMMUNICATION,CONTROL,ANDMANAGEMENT3

簡(jiǎn)介：ANAT89C2051BASEDINTELLIGENTPROXIMITYWARNINGINDICATORFORAUTOMOBILEITINTRODUCESTHEFUNCTIONANDCHARACTERISTICSOFMICROCONTROLLERAT89C2051BASEDONITALOWCOSTHIGHACCURACYMICROMINIATURIZATIONANDDIGITALDISPLAYPROXIMITYWARNINGINDICATORFORAUTOMOBILEISDESIGNEDTHEINDICATORMEASURESTHEDISTANCEANDSPEEDOFTHEAUTOMOBILE,WITHULTRASONICWAVEANDINTEGRATEDHALLUNITANDCONTROLSTHESYSTEMBYTHEREALTIMECONTROLANDDATAPROCESSINGOFTHEMICROCONTROLLERMOREOVERITSCIRCUITRYPRINCIPLEISINTRODUCEDINDETAILASWELLASITSSOFTWAREDESIGNALONGWITHMODERNRHYTHMOFLIFESPEEDINGUP,THEFREQUENCYWHICHTHETRAFFICACCIDENTOCCURREDISINCREASING,FORENHANCESTHESECURITYOFAUTOMOBILEMOVEMENTTHISARTICLEINTRODUCEDONEKINDOFALARMSYSTEMBASEDONMONOLITHICINTEGRATEDCIRCUITCONTROLSTHEAUTOMOBILEGUARDSAGAINSTHITTINGTHISEQUIPMENTTHEMONOLITHICINTEGRATEDCIRCUITREALTIMECONTROLANDTHEDATAPROCESSINGFUNCTION,WITHTHEULTRASONICWAVERANGEFINDERTECHNOLOGY,THESENSORTECHNOLOGYUNIFIES,MAYEXAMINEINTHEAUTOMOBILEMOVEMENTREARAREATHEOBSTACLEANDTHEAUTOMOBILEDISTANCEANDTHEAUTOMOBILEVEHICLESPEED,REVEALSTHEINSTALLMENTDEMONSTRATIONDISTANCETHROUGHTHENUMBER,ANDISAWAYFROMFARANDNEARTHESITUATIONBYTHESOUNDPRODUCTIONELECTRICCIRCUITBASISTOSENDOUTTHEWARNINGSOUNDTHEULTRASONICRANGINGPRINCIPLEIS,AFTERUNCEASINGLYEXAMINESTHEULTRASONICWAVELAUNCHTOMEETTHEECHOWHICHTHEOBSTACLEREFLECTS,THUSDETERMINESTHELAUNCHULTRASONICWAVEANDRECEIVESTHEECHOTHETIMEDIFFERENCETHENEXTRACTSISAWAYFROMSCT/2,CISTHEULTRASONICWAVEWAVEVELOCITY,UNDERTHENORMALTEMPERATURETAKESIS344M/SAFTERSONICSPEEDDETERMINATION,SOLONGASOBTAINSTHEULTRASONICWAVEROUNDTRIPTHETIME,THENOBTAINSTHEDISTANCETHEAUTOMOBILEVEHICLESPEEDSURVEYISINTEGRATESTHESENSORTHROUGHHALLTOREALIZENAMELY,ISLOADEDWITHTHEPERMANENTMAGNETTHETURNTABLEINPUTAXISANDTHEWHEELREVOLUTIONAXISISCONNECTED,WHENTHEWHEELROTATES,THETURNTABLEALONGWITHITROTATION,THISTIME,ONTHETURNTABLEPERMANENTMAGNETCANINTEGRATETHESENSORAFTERHALL,THUSINTEGRATESTHESENSORINHALLTHEINPUTENDTOOBTAINAMAGNETISMSIGNAL,IFTHETURNTABLEDOESNOTSTOPTHEROTATION,HALLINTEGRATESTHESENSORTHENTOBEABLETOOUTPUTTHEROTATIONALSPEEDSIGNALITCANBESAIDTHAT,TOTHEAUTOMOBILEVEHICLESPEEDSURVEYESSENCEINTOTHEROTATIONALSPEEDSIGNALFREQUENCYSURVEYAT89C2051ISALOWPOWERLOSS,THEHIGHPERFORMANCE8CMOSMICROPROCESSOR,ISCOMPATIBLEWITHTHEMCS51SERIESINSTRUCTIONCOLLECTIONANDTHEPIN,HASFOLLOWINGCHARACTERISTIC128BYTESINTERNALRAM,2KBYTESEPROM,FIFTEENI/OLINE,TWOSIXTEENFIXEDTIMECOUNTERS,FIVETWOLEVELOFINTERRUPTSOURCES,ONEENTIREDUPLEXSERIALPORT,INTERNALPRECISELYSIMULATESTHECOMPARATORANDINTERNALSWINGMING,THELOWPOWERLOSSLEAVESUNUSEDANDFALLSTHEELECTRICITYPATTERNTHEWORKINGVOLTAGESCOPE42555V,THEOPERATINGFREQUENCYTAKES12MHZINAT89C2051,TWOSIXTEENFIXEDTIME/COUNTERSREGISTERSIST0ANDT1,MAKEFIXEDTIME/COUNTERS,MAYCOUNTTHEMACHINECYCLE,COUNTSTHEFREQUENCYFORTHEOSCILATIONFREQUENCY1/12WHENMAKESTHECOUNTER,MAYAPPEARSTOONEXTERIORINPUTPINP34/T0ANDP35/T1FROM1TO0CHANGESWHENINCREASE1,COUNTSTHEFREQUENCYFORWAY,WHENULTRASONICWAVELAUNCHSTARTSTOCOUNT,AFTERPINP32RECEIVESTHEECHO,STOPSCOUNTING,T0TIMESNAMELYFORTHEULTRASONICWAVEROUNDTRIPTRANSMISSIONTIME,THEMONOLITHICINTEGRATEDCIRCUITCARRIESONPROCESSINGTOTHISDATA,THENDETERMINESTHEDISTANCETHEINTERNALTIMERT1WORKISCOUNTINGTHEWAY,COUNTSBYP35PININPUTPULSESIGNALCONTROLT1,COUNTSTHEVALUEBYT1TODETERMINETHEAUTOMOBILETHEROTATIONALSPEEDTHEMONOLITHICINTEGRATEDCIRCUITBASISMEASUREDISAWAYFROMANDTHEVEHICLESPEEDCARRIESONTHECOMPARISON,JUDGESWHETHERACTUATESTHEALARMCIRCUITTOREPORTTOTHEPOLICE,LIKEHYPOTHESISWHENTHEVEHICLESPEEDISSMALLEROREQUALTO30KM/S,THESAFEDISTANCESHOULDBEBIGGERTHANISEQUALTO1MWHENTHEVEHICLESPEEDISSMALLEROREQUALTO80KM/S,THESAFEDISTANCESHOULDBEBIGGERTHANISEQUALTO2MWHENTHEVEHICLESPEEDISBIGGERTHAN80KM/S,THESAFEDISTANCESHOULDBEBIGGERTHANISEQUALTO5MTHISINSTALLMENTCONTROLSOFTWAREMUSTCOMPLETETHESYSTEMINITIALIZATION,THECONTROLTRIGGERPULSESIGNALLAUNCHANDTHERECEIVE,ACCORDINGTOFIXEDTIMETHECOUNTDOWNOBSTACLEDISTANCE,ACCORDINGTOCOUNTSTHEFREQUENCYCOMPUTATIONAUTOMOBILEVEHICLESPEED,JUDGESMEASUREDISAWAYFROMWHETHERINTHEMARGINFORSAFETYWHICHTHEVEHICLESPEEDCORRESPONDS,ANDACCORDINGTOCALCULATESHASTHEBCDCODEANDTHECORRESPONDINGFREQUENCYPULSESIGNALWITHTHEJUDGEMENTRESULT,ACTUATESTHEDISPLAYCIRCUITANDTHESOUNDPRODUCTIONELECTRICCIRCUIT

簡(jiǎn)介：中文中文3487字出處出處WANGS,XUY,PANGYAFASTUNDERWATEROPTICALIMAGESEGMENTATIONALGORITHMBASEDONAHISTOGRAMWEIGHTEDFUZZYCMEANSIMPROVEDBYPSOJJOURNALOFMARINESCIENCEANDAPPLICATION,2011,1017075畢業(yè)論文（設(shè)計(jì)）外文翻譯水下強(qiáng)噪聲圖像目標(biāo)分割方法研究學(xué)生姓名指導(dǎo)教師專業(yè)名稱電子信息工程所在學(xué)院信息工程學(xué)院2013年4月二、水下圖像分割傳統(tǒng)的二、水下圖像分割傳統(tǒng)的FCM算法算法FCM聚類分割算法的中心思想是根據(jù)加權(quán)相似性來(lái)衡量像素和聚類中心，迭代優(yōu)化目標(biāo)函數(shù)已確定最佳的聚類。通過(guò)這個(gè)實(shí)現(xiàn)在LH圖像中（L和H待變相關(guān)圖像的寬度和高度），根據(jù)加權(quán)資格隸屬度N（NLH）屬于每個(gè)C聚類中心的圖像中的像素，當(dāng)目標(biāo)函數(shù)最小時(shí)，迭代地優(yōu)化目標(biāo)函數(shù)來(lái)獲得模糊劃分矩陣U和類中心矩陣V。目標(biāo)函數(shù)為通過(guò)拉格朗日乘數(shù)法，建立等式1的一個(gè)必要條件可以推導(dǎo)出這種典型的FCM圖像分割是為了通過(guò)迭代搜尋最優(yōu)聚類中心和隸屬度來(lái)獲得最小目標(biāo)函數(shù)。三、直方圖加權(quán)三、直方圖加權(quán)FCM聚類算法（聚類算法（HWFCM）1、算法描述通過(guò)分析FCM算法，可以發(fā)現(xiàn)影響計(jì)算時(shí)間一個(gè)主要因素是聚類中心的更新頻率太低。在FCM算法中，每個(gè)聚類中心的更新必須等到所有輸入模式完成遍歷。當(dāng)它用在圖像分割中，因?yàn)閳D像的采樣數(shù)據(jù)數(shù)量非常大（每個(gè)圖像尺寸為768576，數(shù)量為442368），計(jì)算就十分耗時(shí)。因此，根據(jù)水下圖像的特性，我們提出了一種快速的FCM分割算法。在迭代處理中，通過(guò)采集圖像強(qiáng)度直方圖的統(tǒng)計(jì)特性作為隸屬度的權(quán)重，目標(biāo)函數(shù)的最優(yōu)解可以得到。因此，它減少了FCM迭代過(guò)程大量的數(shù)據(jù)存儲(chǔ)而且加速了收斂速度。對(duì)于一個(gè)圖像（NLH），F(xiàn)（X,Y）是圖像在（X,Y）位置的灰度值，F(xiàn)∈{0,1,,I?1}，I是所有系列灰度圖像的數(shù)量。定義灰度圖像直方圖為HJ,因此一個(gè)加權(quán)直方圖修改的成員為相應(yīng)的聚類中心新的目標(biāo)函數(shù)為

簡(jiǎn)介：USEOFVOICERECOGNITIONFORCONTROLOFAROBOTICWELDINGWORKCELLABSTRACTTHISPAPERDESCRIBESWORKUNDERWAYTOEVALUATETHEEFFECTIVENESSOFVOICERECOGNITIONSYSTEMSASANELEMENTINTHECONTROLOFAROBOTICWELDINGWORKCELLFACTORSBEINGCONSIDEREDFORCONTROLINCLUDEPROGRAMEDITORACCESSSECURITY,PREOPERATIONCHECKLISTREQUIREMENTS,WELDINGPROCESSVARIABLECONTROL,ANDROBOTMANIPULATORMOTIONOVERRIDESINTHELATTERTWOCATEGORIES,MANUALVOCALCONTROLISBEINGCOMPAREDAGAINSTMANUALTACTILECONTROLANDFULLYAUTOMATICCONTROLINTERMSOFSPEEDOFRESPONSE,ACCURACY,STABILITY,RELIABILITYANDSAFETYINTRODUCTIONVOICERECOGNITIONTECHNOLOGYISNOWRECOGNIZEDASAPOTENTIALMEANSFOREASINGTHEWORKLOADOFOPERATORSOFCOMPLEXSYSTEMSNUMEROUSAPPLICATIONSHAVEALREADYBEENIMPLEMENTED,AREINVARIOUSSTAGESOFDEVELOPMENT,ORAREUNDERCONSIDERATIONTHESEINCLUDEDATAENTRY,CONTROLOFAIRCRAFTSYSTEMS,ANDVOICEIDENTIFICATIONANDVERIFICATIONFORSECURITYPURPOSESVOICECONTROLHASALSOBEENPROPOSEDFORUSEABOARDTHESPACESTATIONONEPRIMEAREAFORAPPLICATIONWOULDBECONTROLOFSOMEFUNCTIONSOFROBOTSUSEDFORINTRAANDEXTRAVEHICULARINSPECTION,ASSEMBLY,REPAIR,SATELLITERETRIEVAL,ANDSATELLITEMAINTENANCEWHENACREWMEMBERISSERVINGINASUPERVISORYCAPACITYORTHESYSTEMISOPERATINGINATELEOPERATIONMODEVOICECONTROLOFSENSORSANDPROCESSVARIABLESWOULDFREETHECREWMEMBER’SHANDSFOROTHERTASKS,SUCHASDIRECTCONTROLOROVERRIDEOFTHEMANIPULATORMOTIONSIMILARLY,THEWORKLOADASSOCIATEDWITHCONTROLOFMANYONBOARDEXPERIMENTSCOULDBEEASEDTHROUGHTHEUSEOFTHISTECHNOLOGYTHISPAPERDESCRIBESTHEAPPLICATIONOFVOICERECOGNITIONFORCONTROLOFAROBOTICWELDINGWORKCELLTHISISACOMPLEXSYSTEMINVOLVINGINPUTSFROMMULTIPLESENSORSANDCONTROLOFAWIDEVARIETYOFROBOTMANIPULATORMOTIONSANDPROCESSVARIABLESWHILEMANYFUNCTIONSAREAUTOMATED,AHUMANOPERATORSERVESINASUPERVISORYCAPACITY,READYTOOVERRIDEFUNCTIONSWHENNECESSARYINTHEPRESENTINVESTIGATION,ACOMMERCIALLYAVAILABLEVOICERECOGNITIONSYSTEMISBEINGINTEGRATEDWITHAROBOTICWELDINGWORKCELLATNASAWIREFEEDGUIDETUBEORBYISSUINGTACTILECOMMANDSTOASERVOMECHANISMUSEOFAVOICERECOGNITIONSYSTEMCOULDELIMINATETHENEEDFORTHEOPERATORTOPLACEHISHANDWITHINTHEWORKINGENVELOPEOFTHEROBOTENDEFFECTOROR,IFSERVOMECHANISMSAREEMPLOYED,COULDIMPROVESPEEDOFRESPONSEANDSTABILITYANOTHERASPECTOFROBOTOPERATIONINANINDUSTRIALENVIRONMENTTHATISVERYIMPORTANTISTHESECURITYOFAPROGRAMEDITINGCAPABILITYOFTHESYSTEMUNDERNOCIRCUMSTANCESSHOULDANYUNAUTHORIZEDPERSONBEABLETOENTERTHISPROGRAMMINGMODEANDALTERTHEROBOT’SPROGRAMAVOICERECOGNITIONSYSTEMCANPROVIDETHENECESSARYSECURITYBYALLOWINGACCESSONLYFORINDIVIDUALSWHOAREAUTHORIZEDANDWHOSEVOICESCANBEIDENTIFIEDBYTHESYSTEMBACKGROUNDROBOTICWELDINGISUNDERDEVELOPMENTBYNASAANDROCKETDYNEFORTHEAUTOMATIONOFWELDSONTHESPACESHUTTLEMAINENGINETHATAREPRESENTLYMADEMANUALLYTHEPROGRAMMABILITYOFAROBOTCANREDUCETHEPERCENTAGEOFWELDINGDEFECTSTHROUGHACOMBINATIONOFCONSISTENCYANDREPEATABILITYUNATTAINABLEBYITSHUMANCOUNTERPARTSTODOTHIS,THEROBOTISPROGRAMMEDTOANOMINALWELDPATHANDLEVELOFWELDPROCESSPARAMETERSIE,CURRENT,TRAVELSPEEDVOLTAGE,WIREADDITIONRATESOMEADJUSTMENTOFTHESEVALUESISOFTENNECESSARYDUETOCONDITIONSCHANGINGDURINGTHEWELDAHUMANMAKINGAMANUALWELDACCOMPLISHESTHISADJUSTMENTREADILY,WHILEAROBOTMUSTRELYONTHELIMITEDTALENTSOFSENSORSANDTHEABILITYOFTHEOPERATORTOOVERRIDEFUNCTIONSWHENNECESSARYSYSTEMINTEGRATIONTHEBASICELEMENTSOFTHEWORKCELLSYSTEMARESHOWNDIAGRAMMATICALLYINTHEILLUSTRATIONTHEULTIMATEGOALOFTHESYSTEMDEVELOPMENTWORKINPROGRESSISTOGENERATEROBOTMANIPULATORPROGRAMSANDWELDPROCESSPROGRAMSOFFLINE,DOWNLOADTHEMTOTHEWORKCELLSUPERVISORYCOMPUTER,THENUSESENSORSUBSYSTEMSTOMAKECLOSEDLOOP

簡(jiǎn)介：PUBLISHEDJANUARY20,2011R2011AMERICANCHEMICALSOCIETY517DXDOIORG/101021/AM101095H|ACSAPPLMATERINTERFACES2011,3,517–521RESEARCHARTICLEWWWACSAMIORGSYNTHESISOFΒMO2CTHINFILMSCOLINAWOLDEN,,?ANNAPICKERELL,?TRUPTIGAWAI,?STERLINGPARKS,?JESSEHENSLEY,?ANDJDOUGLASWAY??DEPARTMENTOFCHEMICALENGINEERING,COLORADOSCHOOLOFMINES,GOLDEN,COLORADO80401,UNITEDSTATES?NATIONALRENEWABLEENERGYLABORATORY,1617COLEBOULEVARD,GOLDEN,COLORADO80401,UNITEDSTATESABSTRACTTHINFILMSOFSTOICHIOMETRICΒMO2CWEREFABRICATEDUSINGATWOSTEPSYNTHESISPROCESSDENSEMOLYBDENUMOXIDEFILMSWEREFIRSTDEPOSITEDBYPLASMAENHANCEDCHEMICALVAPORDEPOSITIONUSINGMIXTURESOFMOF6,H2,ANDO2THEDEPENDENCEOFOPERATINGPARAMETERSWITHRESPECTTODEPOSITIONRATEANDQUALITYISREVIEWEDOXIDEFILMS100500NMINTHICKNESSWERETHENCONVERTEDINTOMOLYBDENUMCARBIDEUSINGTEMPERATUREPROGRAMMEDREACTIONUSINGMIXTURESOFH2ANDCH4XRAYDIFFRACTIONCONFIRMEDTHATMOLYBDENUMOXIDEISCOMPLETELYTRANSFORMEDINTOTHEΒMO2CPHASEWHENHEATEDTO700?CINMIXTURESOF20CH4INH2THEFILMSREMAINEDWELLADHEREDTOTHEUNDERLYINGSILICONSUBSTRATEAFTERCARBURIZATIONXRAYPHOTOELECTRONSPECTROSCOPYDETECTEDNOIMPURITIESINTHEFILMS,ANDMOWASFOUNDTOEXISTINASINGLEOXIDATIONSTATEMICROSCOPYREVEALEDTHATTHEASDEPOSITEDOXIDEFILMSWEREFEATURELESS,WHEREASTHECARBIDEFILMSDISPLAYACOMPLEXNANOSTRUCTUREKEYWORDSTHINFILM,CARBIDE,OXIDE,PLASMAENHANCEDCHEMICALVAPORDEPOSITION,CATALYST’INTRODUCTIONMOLYBDENUMCARBIDEISAVERSATILEMATERIALWITHPOTENTIALAPPLICATIONSINAVARIETYOFAREASMOLYBDENUMCARBIDEEXHIBITSCATALYTICPROPERTIESANALOGOUSTOPLATINUMGROUPMETALS,ANDINTHELASTFEWDECADES,EFFORTSHAVEBEENMADETOEXPLOITTHISTRAITINANUMBEROFCHEMICALPROCESSESINCLUDINGAMMONIASYNTHESIS,HYDROCARBONREFORMING,WATERGASSHIFT,H2PRODUCTION,ANDALCOHOLSYNTHESIS17ASATHINFILM,THEHIGHHARDNESSANDTHERMALSTABILITYOFTHETRANSITIONMETALCARBIDESMAKETHEMUSEFULASWEARRESISTANTMATERIALS8,9MORERECENTSTUDIESHAVEFOCUSEDONTHEOPTOELECTRONICPROPERTIESOFMOLYBDENUMCARBIDEFORARANGEOFAPPLICATIONSINCLUDINGMIRRORS,10DIFFUSIONBARRIERS,11INTERCONNECTS,12ANDELECTRONFIELDEMISSION13OURINTERESTISINTHECREATIONOFINEXPENSIVEALTERNATIVESTOPLATINUMGROUPMETALSFORSURFACEDISSOCIATIONOFH2FORMATIONOFTHISMATERIALASATHINFILMWOULDFACILITATEFUNDAMENTALSTUDIESOFCATALYSTPERFORMANCENUMEROUSTECHNIQUESHAVEBEENUSEDTODEPOSITMOLYBDENUMCARBIDEFILMSINCLUDINGCHEMICALVAPORDEPOSITIONCVD,8,14PHYSICALVAPORDEPOSITIONPVD,9,11ANDELECTRODEPOSITION15THEMOCSYSTEMISQUITECOMPLEX,WITHNUMEROUSSTABLEANDMETASTABLECOMPOUNDSANDCRYSTALPHASESTHATHAVEBEENOBSERVED14,16CONTROLOFPHASEPURITYHASBEENPROBLEMATICFORBOTHCVDANDPVDAPPROACHES,ANDFILMSOFTENCONTAINAMIXTUREOFCARBONRICHPRODUCTSTHATDISPLAYACOMPLEXDEPENDENCEONTHESPECIFICOPERATINGCONDITIONSEMPLOYED8,11,14INCONTRAST,FORCATALYSISAPPLICATIONSITISRELATIVELYSTRAIGHTFORWARDTOACHIEVETHEDESIREDΒMO2CPHASEINPOWDERFORM14THEKEYDEVELOPMENTCAMEFROMBOUDARTANDCOWORKERS1,2WHODEVELOPEDAMETHODTOCONVERTDENSEMOO3POWDERSINTOHIGHSURFACEAREAMO2CBYTEMPERATUREPROGRAMMEDREACTIONORTPR,USINGMIXTURESOFHYDROCARBONSDILUTEDINH2THEMECHANISMFORTHEMOO3TOMO2CTRANSFORMATIONINVOLVESTHESUBSTITUTIONOFCARBONFOROXYGENINTHEMOO3LATTICE,WITHLITTLEDISPLACEMENTOFTHEMOATOMSDURINGTHEREACTIONBECAUSETHEMOLARVOLUMEOFMO2CISSMALLERTHANTHEMOLARVOLUMEOFMOO3,MICROPORESFORMASTHEOXIDETRANSFORMSINTOTHECARBIDEUNDERPROPERCONDITIONSTHEMOO3ISCONVERTEDINTOMO2CWITHOUTFORMINGMETALLICMOASAREACTIONINTERMEDIATEMETALSINTERINGISAVOIDEDUSINGTHISMETHOD,ANDUNSUPPORTEDCATALYSTSCANBEPREPAREDWITHVERYHIGHSURFACEAREAS5090M2/GREBROVETAL5USEDTHISSTRATEGYTOFORMCATALYSTCOATINGSTHROUGHTHECARBURIZATIONOFPREOXIDIZEDMOLYBDENUMSHEETS,ANDAPPLIEDTHEMTOTHEWATERGASSHIFTREACTIONTHEGOALOFTHISWORKWASTOPRODUCEPHASEPUREΒMO2CFILMSFORFUTURESTUDYASMODELCATALYSTLAYERSBELOWWEDESCRIBEATWOSTEPSYNTHESISAPPROACHFIRST,DENSEMOLYBDENUMOXIDEFILMSAREDEPOSITEDONSILICONUSINGPLASMAENHANCEDCHEMICALVAPORDEPOSITIONPECVDUSINGMIXTURESOFMOF6/H2/O2THEUSEOFMOF6ANDTHISREACTIONCHEMISTRYISSOMEWHATUNIQUE,ASPREVIOUSCVDOFMOCONTAININGCOMPOUNDSHAVEEMPLOYEDEITHERMOCO617,18ORMOCL514,19ASTHEMOLYBDENUMPRECURSORTHEDEPENDENCEOFOXIDEGROWTHRATEANDQUALITYONPECVDPARAMETERSISDESCRIBEDTHEUSEOFPECVDTOFORMTHEOXIDEALLOWSTHESEFILMSTOBEPRODUCEDONABROADERSETOFSUBSTRATESTHEFILMSWERETHENTRANSFORMEDINTOTHEΒMO2CPHASEBYAPPLYINGTPRCONDITIONSDEVELOPEDBYTHECATALYSISCOMMUNITYTHEEVOLUTIONOFFILMCOMPOSITIONANDSTRUCTURETHROUGHOUTTHESEPROCESSESISQUANTIFIEDUSINGASUITEOFANALYTICALTECHNIQUES’EXPERIMENTALSECTIONOXIDESYNTHESISMOLYBDENUMOXIDEFILMSWEREDEPOSITEDUSINGMIXTURESOFMOF6/H2/O2INACAPACITIVELYCOUPLEDPECVDSYSTEMTHISPECVDCHEMISTRYADOPTSASIMILARAPPROACHTHATHASBEENRECEIVEDNOVEMBER11,2010ACCEPTEDDECEMBER31,2010519DXDOIORG/101021/AM101095H|ACSAPPLMATERINTERFACES2011,3,517–521ACSAPPLIEDMATERIALSINTERFACESRESEARCHARTICLETHEOBSERVEDPEAKPOSITIONOFTHEASDEPOSITEDFILMATABINDINGENERGYBEOF2328EVISINGOODAGREEMENTWITHTHEMOT6STATEOFFULLYOXIDIZEDMOO3THEDORBITALPEAKSARESEPARATEDBY31EVANDAPPEARINTHETHEORETICALLYEXPECTED32RATIO,24PROVIDINGFURTHERSUPPORTTHATTHEMOISPRESENTINASINGLEOXIDATIONSTATEOFCOURSEHYDROGENCANNOTBEDETECTEDBYXPS,BUTTHEPOSITIONOFMOSPECTRAINITSFULLYOXIDIZEDSTATESUPPORTSITSABSENCEXPSANALYSISOFMOLYBDENUMOXIDEFILMSINTERCAL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簡(jiǎn)介：1INTRODUCTIONVITAMINCOCCURSINDIFFERENTCONCENTRATIONSINAVARIETYOFNATURALSAMPLESITISADDEDTOSEVERALPHARMACEUTICALPRODUCTSASANESSENTIALINGREDIENT,ASTABILIZERFORVITAMINBCOMPLEX,ANDASANANTIOXIDANTCONSEQUENTUPONITSDESIRABLEEFFECTS,ITISWIDELYUSEDINTHETREATMENTOFCERTAINDISEASESSUCHASSCURVY,COMMONCOLD,ANEMIA,HAEMORRHAGICDISORDERS,WOUNDHEALING,ANDEVENINFERTILITY,TOMENTIONSOMESTARKCASESITISCONSIDEREDESSENTIALFORTHEDEVELOPMENTANDREGENERATIONOFMUSCLES,BONES,TEETHANDSKINTHEINCREASINGUSEOFPHARMACEUTICALSANDOTHERNATURALSAMPLESCONTAININGVITAMINCHASMEANTTHATTHEPRACTICISINGCHEMISTSSHOULDDEVELOPANALYTICALPROCEDURESFORITSDETERMINATIONWHICHARESIMPLETOOPERATE,RAPID,ACCURATE,SENSITIVEANDSELECTIVETHEDESIRETODEVELOPMETHODSWITHIDEALCHARACTERISTICSHASRESULTEDALARGENUMBEROFPROCEDURESWITHVARYINGAPPLICABILITYMANYINSTRUMENTBASEDANALYSESINCLUDINGFLUOROMETRY1–4,HPLC5–10,POLAROGRAPHY11–13ANDENZYMATIC14,15METHODSAREREPORTEDINTHELITERATUREBUTDUETOTHEIRINHERENTLIMITATIONS,THESETECHNIQUESARENOTCOMMONLYUSEDFORROUTINEANALYSESHOWEVER,PHOTOMETRICMETHODSAREPARTICULARLYATTRACTIVEBECAUSEOFTHEIRSPEEDANDSIMPLICITYCONSEQUENTLY,ALARGENUMBEROFSUCHPROCEDURESHAVEBEENDEVELOPEDFORTHEDETERMINATIONOFASCORBICACIDAATHOUGHSOMESHORTREVIEWS16–18HAVEBEENREPORTED,ACRITICALASSESSMENTOFTHESEMETHODSISDESIRABLETOEXAMINETHEIRSALIENTFEATURESANDUTILITYTHISREVIEWISANATTEMPTTOASSESSEXCLUSIVELYTHEEXISTINGSPECTROPHOTOMETRICMETHODSFORTHEDETERMINATIONOFVITAMINCASREGARDSTHEIRSIMPLICITY,RAPIDITY,BEER’SLAWRANGE,SENSITIVITY,SELECTIVITYANDAPPLICABILITYITISPRIMARILYBASEDONTHEINFORMATIONCOLLECTEDTHROUGHTHECHEMICALABSTRACTSFORTHEPERIOD1970TOMID19972RESULTSANDDISCUSSIONSEVERALDYESSUCHAS2,6DICHLOROPHENOLINDOPHENOLDCIP,DIMETHOXYDIQUINONEDMDQ,NINHYDRIN,FASTREDALSALTAND2′,7′DICHLOROFLUORESCEINETCHAVEBEENUSEDFORTHEDETERMINATIONOFVITAMINCAMONGTHESEDYES,DCIPHASBEENMOSTEXTENSIVELYSTUDIEDITISINCLUDEDINTHEOFFICIALTITRIMETRICMETHODSASREPORTEDINDIFFERENTPHARMACOPOEIAS19–21ANDITALSOFORMSTHEBASISOFMANYCOLORIMETRICMETHODSTHEBLUEDYEDCIPISREDUCEDTOTHECOLORLESSFORMONADDITIONOFASCORBICACIDASSHOWNINFIG1,BUTITGIVESAPINKCOLORTOTHEACIDICSOLUTIONSUSINGTHEDYE,ASCORBICACIDPRESENTINHUMANURINE22ANDPROCESSEDPOTATOES23HASBEENDETERMINEDTHEEXCESSDYECANBEEXTRACTEDWITHXYLENEORBUTANOL24MANYSUBSTANCESWHICHARECAPABLEOFREDUCINGTHEDYERESULTINGFROMTHEPREPARATIONANDPROCESSINGOFFOODSAMPLESINTERFEREFLOWDIALYSISPROPOSEDBYGARYETAL25ANDCONTINUOUSFLOWSYSTEMSHAVEBEENUSEDTOMONITORTHEDECREASEINABSORBANCEOFDCIPSUCHAUTOMATEDSYSTEMSAPPEARTOBEJUSTIFIEDONLYWHENROUTINEANALYSISOFALARGEANALYTICALSCIENCESOCTOBER1998,VOL14PHOTOMETRICMETHODSFORTHEDETERMINATIONOFVITAMINCSATYAPARYA?,MEENAKSHIMAHAJANANDPREETIJAINDEPARTMENTOFCHEMISTRY,KURUKSHETRAUNIVERSITY,KURUKSHETRA–136119,HARYANASTATE,INDIATHEIMPORTANCEOFVITAMINCTOTHEHUMANBODYISWIDELYACKNOWLEDGEDTHROUGHOUTTHEGLOBETHEDEFICIENCYOFTHISVITAMINLEADSTOVARIOUSDISEASESINVIEWOFITSIMPORTANCE,NUMEROUSMETHODSINCLUDINGSPECTROPHOTOMETRICONESHAVEBEENDEVELOPEDFORITSDETERMINATIONINPHARMACEUTICALS,FOODSANDBIOLOGICALSAMPLESACOMPREHENSIVEREVIEWOFTHEAVAILABLESPECTOPHOTOMETRICMETHODSFORTHEDETERMINATIONOFASCORBICACIDISPRESENTEDKEYWORDSVITAMINCDETERMINATION,SPECTROPHOTOMETRICMETHOD?TOWHOMCORRESPONDENCESHOULDBEADDRESSEDFIG1THEREDUCTIONOFDCIPWITHASCORBICACIDASCORBICACIDDCIPOXIDIZED,BLUEPINKDEHYDROASCORBICACIDDCIPREDUCED,COLORLESSANDTRINITROBENZENE47INTARTRATEBUFFERWHENSTUDIEDFORITSDETERMINATIONOVERTHECONCENTRATIONRANGES2–50AND0–125ΜGML–1OFASCORBICACIDRESPECTIVELYMETHANOLICSOLUTIONOFRESORCINOL48GIVESAPALEYELLOWCOLORΛMAX425NMWITHASCORBICACIDINHYDROCHLORICACIDMEDIUM,OBEYINGBEER’SLAWFOR80–400ΜGML–14CHLORO7NITROBENZOFURAZANE49FORMSABLUISHGREENCOLOREDSPECIESWITHASCORBICACIDINPRESENCEOF02MSODIUMHYDROXIDETHEABSORBANCEISMEASUREDAT582NMAFTERDILUTINGTHEREACTIONCONTENTSWITH50V/VAQUEOUSACETONESOLUTIONBEER’SLAWISOBEYEDINTHECONCENTRATIONRANGE5–20ΜGML–1THECOLOREDPRODUCTISSTABLEFOR30MINONLYWHENKEPTAWAYFROMDIRECTSUNLIGHTORARTIFICIALDAYLIGHTTHEMETHODISREPORTEDFREEFROMTHEINTERFERENCEOFALLOTHERVITAMINSANDMINERALSPRESENTINMULTIVITAMINPREPARATIONSANDCANBEAPPLIEDTOTHEANALYSISOFPHARMACEUTICALS,FRESHFRUITJUICESANDVEGETABLESHASHMIETAL50PROPOSEDAMETHODBASEDONTHEREACTIONOF2,3,5TRIPHENYLTETRAZOLIUMCHLORIDEWITHASCORBICACIDINALKALINEMEDIUMTHEPINKSOLUTIONISALLOWEDTOSTANDINTHEDARKFOR30MINAT25?CITOBEYSBEER’SLAWOVERTHERANGE5–25ΜGML–1SUGARS15ΜGML–1EXCEPTSUCROSEINTERFEREBYFORMINGASIMILARCOLORTOTHATOFTHEREAGENTRIBOFLAVIN,CYANOCOBALAMINANDFOLICACIDINTERFEREDUETOTHEIROWNCOLORBEUTLERETAL51,52INVESTIGATEDTHEUSEOFMETHYLTHIAZOLYLTETRAZOLIUMSALTINPRESENCEOFASCORBATEOXIDASEENZYMEAND34,5DIMETHYLTHIAZOLYL2YL2,5DIPHENYLTETRAZOLIUMCHLORIDEORBROMIDEINTHEPRESENCEOF5METHYLPHENAZINIUMMETHYLSULFATEELECTRONCARRIERATPH35FORTHEDETERMINATIONOFASCORBICACIDINFOODS,FRUITJUICESANDVEGETABLESJUICESTHESEREACTIONSINVOLVETHEFORMATIONOFFORMAZONΛMAX578NMTHEINTERFERENCEOFSULFURDIOXIDEREQUIRESTREATMENTWITHFORMALDEHYDE,ANDCOLORINTERFERENCEFROMDARKJUICESISREMOVEDBYDECOLORIZATIONWITH1POLYVINYLPOLYPYRROLIDONEBEFOREFILTRATIONSORBITOL,ALCOHOLANDOXALATEINTERFEREWITHTHEASCORBICACIDOXIDASEHOWEVER,THEEFFECTOFOXALATECANBECHECKEDBYADDINGASLIGHTEXCESSOFCAIIIONSOTHERDERIVATIVESSUCHAS2,5DIPHENYL3THIAZOLYLTETRAZOLIUMCHLORIDE53ATPH122,2PIODOPHENYL3PNITROPHENYL5PHENYLTETRAZOLIUMCHLORIDEATPH105ΛMAX540NMAND2,2′,5,5′TETRA4NITROPHENYL3,3′3,3′DIMETHOXY4,4′BIPHENYLDITETRAZOLIUMCHLORIDE54HAVEALSOBEENEMPLOYEDFORTHEASSAYOFASCORBICACIDTHECOUPLINGOF2,4DINITROPHENYLHYDRAZINEDNPHWITHKETONICGROUPSOFDHAAANDDIKETOGULONICACIDDKGAHASBEENTHEBASISOFMANYMETHODSFORTHEDETERMINATIONOFTOTALVITAMINCCONTENTSPROTEINSPRESENTINTHESAMPLESAREPRECIPITATEDBYADDINGTRICHLOROACETICACIDTCAANDALIQUOTSOFFILTRATEARESHAKENWITHACID–WASHEDCHARCOALNORITORACTIVATEDCHARCOAL55TOCLARIFYTHESOLUTIONSANDTOOXIDIZEAATODHAAAREDUCINGMEDIUMISPRODUCEDBYADDINGTHIOUREAPRIORTODNPHADDITION,OTHERWISEUNSPECIFICCOLORATIONISGIVENBYOXIDANTSTHEOSAZONESΛMAX545NMTHUSFORMEDDURINGTHE3HINCUBATIONAT37?CBYTHEREACTIONOFDNPHANDDHAAAREDISSOLVEDBYADDING85H2SO4VITAMINCCANBEEXTRACTEDWITHMETAPHOSPHORICACID–STANNOUSCHLORIDESOLUTIONWITHOUTCHARCOALTREATMENTFORDIFFERENTIALDETERMINATIONOFDKGA,DHAAANDAAINTHESAMETISSUEEXTRACTSTHEINTERFERENCEOFSUGARSCANBEMINIMIZEDBYCARRYINGOUTINCUBATIONAT15?CANDMEASURINGTHEABSORBANCEONLYAFTERADDINGSULFURICACIDFOR75MIN56THEUSEOFSEVERALACIDMIXTURESHASBEENPROPOSEDFORREPLACINGTHETEDIOUSDROPWISEADDITIONOFSULFURICACIDLACKOFSPECIFICITYISFOUNDWITHMANYOFTHESEMETHODSINTERFERINGOSAZONESCANBESEPARATEDBYCHROMATOGRAPHICMETHODSSUCHASTLC57ANDHPLC58,BUTATTHECOSTOFMAKINGTHESEPROCEDURESTEDIOUSANDCUMBERSOMETHENATUREOFDNPHMETHODSFORTOTALVITAMINCALSOMAKESITAMENABLETOAUTOMATICFLOWTHROUGHANALYSES59–61PHENYLHYDRAZINIUMCHLORIDE62PRODUCESAYELLOWCOLORΛMAX395NMWHENTREATEDWITHASCORBICACIDIN01MHCLMEDIUMTHEREACTIONCONTENTSAREKEPTFOR1HINANINCUBATORORWATERBATHAT50±2?C,THUSMAKINGTHEMETHODTIMECONSUMINGBEER’SLAWISOBEYEDINTHERANGE25–100ΜGOFASCORBICACIDNOINTERFERENCEISOBSERVEDFROMOTHERVITAMINS,MINERALS,GLUCOSE,SUCROSE,EXCIPIENTSANDREDUCINGAGENTSHOWEVER,THEPRESENCEOFEXCESSIVEAMOUNTSOFRIBOFLAVINREQUIRESTHEADDITIONOF05GTALC,WHICHIMPARTSAYELLOWCOLORTOTHESOLUTION3METHYL2BENZOTHIAZOLONEHYDRAZONE63REACTSINTHEPRESENCEOFSODIUMMETAPERIODATETOFORMABLUECOLOREDSOLUTIONΛMAX630NMWHICHHELPSINTHEDETERMINATIONOFASCORBICACIDOVERTHERANGE6–14MEQML–1WANG64SUGGESTEDTHEUSEOFPOTASSIUMIODATEFORTHEDETERMINATIONOFVITAMINCINPHARMACEUTICALSTHEABSORBANCEISMEASUREDEITHERINTHEUVREGION288NMORINTHEVISIBLEREGION445NMBESIDESAQUEOUSPHASEMEASUREMENTS,THEYELLOWPRECIPITATECANBEEXTRACTEDINTOCHLOROFORM65ΛMAX514NMTHEICL2–GENERATEDINTHEOXIDATIONOFAABYIODATE66INACIDMEDIUMINTHEPRESENCEOFCL–IONSHASBEENUSEDTOIODINATE2′,7′DICHLOROFLUORESCEINDYETHEIODINATEDDYEΛMAX525NMOBEYSBEER’SLAWUPTO300ΜGΕ881103SOFTDRINKS67HAVEBEENANALYZEDUSINGTHEREACTIONOFIODINEINANACETICACIDMEDIUMΛMAX350NMSIRIVIDYAANDBALASUBRAMANIAN68REPORTEDANINDIRECTPROCEDUREBASEDONTHEOXIDATIONOFASCORBICACIDBYAKNOWNEXCESSOFIODATEINTHEPRESENCEOFACIDFORTHEANALYSISOFPHARMACEUTICALSANDFRESHFRUITJUICESTHEUNREACTEDIODATEISUSEDFORHYDROXYLAMINEOXIDATIONTOGENERATENITRITE,WHICHISTHENDIAZOTIZEDWITHSULFANILICACIDTHERESULTINGDIAZONIUMSALTISCOUPLEDWITHN1NAPHTHYLETHYLENEDIAMINEDIHYDROCHLORIDETOFORMANAZODYEΛMAX540NMTHEPROCEDUREISACOMPLICATEDONEASITINVOLVESMANYSTEPSTHEREACTIONOFHEXACYANOFERRATEIII695WASUSEDFORTHEDETERMINATIONOFMICROQUANTITIESOFVITAMINCBYMEASURINGTHEDECREASEINCOLORINTENSITYOFTHEREAGENT5ΛMAX420NMINMCILVAINEBUFFERPH52891ANALYTICALSCIENCESOCTOBER1998,VOL14

簡(jiǎn)介：開題報(bào)告表開題報(bào)告表課題名稱基于C的網(wǎng)上書店的設(shè)計(jì)與實(shí)現(xiàn)課題來(lái)源課題類型AX指導(dǎo)教師學(xué)生姓名學(xué)號(hào)專業(yè)一、設(shè)計(jì)的目的當(dāng)今的社會(huì)是一個(gè)信息化的社會(huì)，互聯(lián)網(wǎng)的出現(xiàn)加速了這個(gè)社會(huì)信息的傳播。隨著INTERNET的普及，互聯(lián)網(wǎng)以一股巨大變革力量的面貌出現(xiàn)在商務(wù)關(guān)系領(lǐng)域。其強(qiáng)大的功能已為人們深刻認(rèn)識(shí),它已進(jìn)入人類社會(huì)的各個(gè)領(lǐng)域并發(fā)揮著越來(lái)越重要的作用。因?yàn)榫W(wǎng)絡(luò)本身就是信息的載體，它與普通的書店等書籍出售場(chǎng)所相比，具有速度快、容量大、費(fèi)用少、使用方便等優(yōu)勢(shì)。比如，從網(wǎng)上購(gòu)書你可以快速分類瀏覽到全國(guó)各地的書籍報(bào)價(jià)。通過(guò)網(wǎng)絡(luò)進(jìn)行購(gòu)書，可以彌補(bǔ)實(shí)體書店購(gòu)買的不足，網(wǎng)上購(gòu)書不受時(shí)間的限制，并且可以買到全國(guó)各地的書籍，較少出現(xiàn)斷貨的情況，另外，網(wǎng)上書店節(jié)約了成本，相比之下價(jià)格要比實(shí)體書店的更實(shí)惠。對(duì)購(gòu)書者來(lái)說(shuō)，不僅節(jié)約了時(shí)間也買到了物美價(jià)廉的圖書。二、設(shè)計(jì)的要求21總體要求1建立對(duì)圖書提供全面管理的信息系統(tǒng)；2對(duì)所有的圖書、客戶提供全面管理；3對(duì)圖書詳細(xì)信息提供管理。22功能要求1在INTERNET,客戶可通過(guò)IE或其他瀏覽器瀏覽書目信息；2通過(guò)互聯(lián)網(wǎng)，可提交訂單；3具有購(gòu)物車功能；4客戶能通過(guò)書名來(lái)檢索書籍；5客戶可在進(jìn)行注冊(cè)，成為會(huì)員；6客戶能查看當(dāng)前訂單和以往訂單；7書店管理員能查找客戶信息；8書店管理員在發(fā)貨后能改寫訂單中的發(fā)貨日期；23性能要求1系統(tǒng)可以對(duì)圖書的庫(kù)存進(jìn)行統(tǒng)計(jì)；2系統(tǒng)界面設(shè)計(jì)友好，操作方便、靈活；3具有高可靠性和冗錯(cuò)能力，不允許系統(tǒng)在工作時(shí)間停機(jī)，不允許系統(tǒng)丟失圖書信息。4具有安全檢查機(jī)制，非法用戶不能隨便修改網(wǎng)站會(huì)員信息等。三、思路1、前臺(tái)設(shè)計(jì)思路開題報(bào)告內(nèi)容（調(diào)研資料的準(zhǔn)備，設(shè)計(jì)的目的、要求、思路與預(yù)期成果；任務(wù)完成的階段內(nèi)容及時(shí)間安排；完成設(shè)計(jì)（論文）所具備的條件因素等。）指導(dǎo)教師簽名日期（可加頁(yè)）課題類型（1）A工程設(shè)計(jì)；B技術(shù)開發(fā)；C軟件工程；D理論研究；（2）X真實(shí)課題；Y模擬課題；Z虛擬課題

簡(jiǎn)介：1424412536/07/2500?2007IEEEPROCEEDINGSOFHDP’07DESIGNOFPWMCONTROLLERINAMCS51COMPATIBLEMCUYUELIHU,WEIWANGMICROELECTRONICRESEARCHSANDERS,SR,“ARCHITECTUREANDICIMPLEMENTATIONOFADIGITALVRMCONTROLLER,”POWERELECTRONICS,IEEETRANSACTIONSONVOLUME18,ISSUE1,PART2,JAN2003PAGES356–3647SMITH,KM,JRLAI,ZSMEDLEY,KM“ANEWPWMCONTROLLERWITHONECYCLERESPONSE,”POWERELECTRONICS,IEEETRANSACTIONSONVOLUME14,ISSUE1,JAN1999PAGES142150