物品存储系统英文文献及译文

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1、职场大变样社区(www.zcdby.com):下载毕业设计成品全套资料，全部50元以下英文文献及中文翻译VirusIntroductionViruseswillcausemuchconfusion.Evensomevirus“experts”willmisinformthecauseofthevirus.Let’sdefinewhatwemeanbyvirus.Avirusisaprogramthatreproducesitsowncodebyattachingitselftootherexecutablefiles，sotheviruscodeisexecutedwhentheinf

2、ectedexecutablefileisexecuted.Here,theprogram(COMorEXEfile)referstoanexecutablefile.Toattachmightmeanphysicallyaddingtotheendofafile,insertingintothemiddleofafile,orsimplyplacingapointertoadifferentlocationonthedisksomewherewheretheviruscanfindit.Mostvirusesplaceself-replicatingcodesinotherprogr

3、ams,sothatwhenthoseotherprogramsareexecuted，evenmoreprogramsare"infected”withtheself-replicatingcodes.Theseself-replicatingcodes，whencausedbysomeevent，maydoapotentiallyharmfulacttoyourcomputer.Themacroportionofadatafilemaybemuchmorecritical(e.g.，aMicrosoftWorddocument),butlessobvious.Morerecentl

4、y,scriptswrittenforInternetwebsitesand/orincludedinE-mailcanalsobeexecutedandinfected.Similartoviruses，youcanalsofindmaliciouscodesinTrojanHorses,worms，andlogicbombs.VirusBehavior—InfectionPhaseViruseshavemanydifferentforms，buttheyallpotentiallyhavetwophasestotheirexecution:theinfectionphaseandt

5、heattackphase.Nowwefirstlydiscusstheinfectionphase.Whenthevirusexecutesitcaninfectotherprograms.Somevirusesinfectotherprogramseachtimetheyareexecuted;othervirusesinfectonlyuponacertaincause.Thiscausecouldbeanything,adayortime，anexternaleventonyourPC，acounterwithinthevirus，etc.Viruswriterswantthe

6、irprogramstospreadasfaraspossiblebeforeanyonenoticesthem.ManyvirusesgoresidentinthememoryofyourPC(likeTSR).Thevirusmaysilentlyresidentinmemorywaitingforyoutoaccessadiskette,copyafile，orexecuteaprogram，beforeitinfectsanything.Becausethecauseconditiontheyusefortheirinfectionishardtoguess，virusesar

7、emoredifficulttoanalyze.ResidentvirusesfrequentlytakeoverportionsofthesystemsoftwareonthePCtohidetheirexistence.Thistechniqueiscalledstealth.Polymorphictechniquesalsohelpvirusestoinfectyetavoiddetection.Notethatwormsoftentak