实体安全主要涉及信息系统的硬件及其运行环境，其安全与否对于网络、软件、数据等安全有着重要影响。试结合机房应用，阐述实体安全应该采取的各种防护策略。
一、场地环境安全
1、场地存放计算机、网络硬件设备的机房等信息系统的中必区域，应该选择远离存放易燃、易爆、易腐蚀物品的地方;远离有害气体源;远离强的动力设备和机械;避开高压线、雷达站、无线电发射台和微波中继线路;远离强振动源和噪声源;具备较好的防风、防火、防水、防震及防雷击的条件。
2、空气调节系统机房内空调系统是保证计算机系统正常运行的重要设备之一。通过人为控制，使得机房能够保持适当的温度(一般20℃左右)、合适的湿度(一般30%-70%)和洁净度，以便计算机硬件能够正常工作。
3、防火管理为避免机房发生火灾造成大的损失，应该采取如下防火安全策略：
(1)配备烟火报警装置。
(2)制定防火管理应急预案。
(3)设计防火分离区(如防火门、隔离带等)。
(4)配备灭火器材。
二、硬件安全
1、硬件设备的档案管理对设备型号、测试、安装、存放、维修、使用等管理信息进行登记。
2、防电磁干扰计算机及其相关设备在工作时会产生一定量的电磁波，当它强度超过一定量时，对其自身和周边设备产生干扰影响，导致设备不能正常工作。为了解决这类问题，常采取电磁屏蔽、接地系统等措施。
3、防电磁泄漏。电磁泄漏是指在信息系统工作时，有用的信息电磁信号被高灵敏度设备截获，从而导致信息泄漏，威胁信息安全。为此，人们常采取电子屏蔽技术和物理抑制技术消除电磁泄露。
4、电源安全电源是一切电器设备安全工作的基础，其安全管理要考虑如下因素：
(1)容量应有宽裕，一般电源功率要超过所有设备负载的125%。
(2)应急电源，为了应对停电等突发事件，必须配备不间断电源，以便做应急备份的工作;对于重要的不可中断的服务器应该有备用电源。
三、介质安全
介质是存放信息的载体，包括各类磁盘、磁带、光盘等。除了进行分门别类地存储和管理外，要注意防火、防高温、防潮，防水、防霉、防磁和防盗等，并定期检查和清理。对于重要的信息，不仅从实体上进行保护，还要通过数据加密处理，从内容上加以保护。
暂无解析
Weregret______unabletoagreetothebuyer'srequestasstatedintheL/Cstipulationsforinsurancetobecovereduptotheinlandcity.
Don'twashthosefossils!
StandardmuseumpracticecanwashawayDNA.
1.Washing,brushingandvarnishingfossils—allstandardconservationtreatmentsusedbymanyfossilhuntersandmuseumcuratorsalike—vastlyreducesthechancesofrecoveringancientDNA.
2.Instead,excavatorsshouldbehandlingatleastsomeoftheirbountywithgloves,andfreezingsamplesastheyarefound,dirtandall,concludesapaperintheProceedingsoftheNationalAcademyofSciencestoday.
3.AlthoughmanypalaeontologistsknowanecdotallythatthisisthebestwaytouptheoddsofextractinggoodDNA,Eva-MariaGeigloftheJacquesMonodInstituteinParis,France,andhercolleagueshavenowshownjusthowimportantconservationpracticescanbe.Thisinformation,theysay,needstobehammeredhomeamongthepeoplewhoareactuallyoutinthefielddiggingupbones.
4.Geiglandhercolleagueslookedat3,200-year-oldfossilbonesbelongingtoasingleindividualofanextinctcattlespecies,calledanaurochs.ThefossilsweredugupatasiteinFranceattwodifferenttimes—eitherin1947,andstoredinamuseumcollection,orin2004,andconservedinsterileconditionsat-20oC.
5.Theteam'sattemptstoextractDNAfromthe1947bonesallfailed.Thenewlyexcavatedfossils,however,allyieldedDNA.
6.Becausetheboneshadbeenburiedforthesameamountoftime,andinthesameconditions,theconservationmethodhadtobetoblamesaysGeigl."AsmuchDNAwasdegradedinthese57yearsasinthe3,200yearsbefore,"shesays.
Washin,washout
7.Becausemanypalaeontologistsbasetheirworkontheshapeoffossilsalone,theirmethodsofconservationarenotdesignedtopreserveDNA,Geiglexplains.
8.Thebiggestproblemishowtheyarecleaned.Fossilsareoftenwashedtogetheron-siteinalargebath,whichcanallowwater—andcontaminantsintheformofcontemporaryDNA—topermeateintotheporousbones."NotonlyistheauthenticDNAgettingwashedout,butcontaminationisgettingwashedin,"saysGeigl.
9.MostancientDNAspecialistsknowthisalready,saysHendrikPoinar,anevolutionarygeneticistatMcMasterUniversityinOntario,Canada.Butthatdoesn'tmeanthatbestpracticehasbecomewidespreadamongthosewhoactuallyfindthefossils.
10.GettingholdoffossilsthathavebeenpreservedwiththeirDNAinmindreliesoncloserelationshipsbetweenlab-basedgeneticistsandtheexcavators,sayspalaeogeneticistSvantePbooftheMaxPlanckInstituteforEvolutionaryAnthropologyinLeipzig,Germany.Andthatonlyoccursinexceptionalcases,hesays.
11.Pbo'steam,whichhasbeensequencingNeanderthalDNA,continuallyfacestheseproblems."WhenyouwanttostudyancienthumanandNeanderthalremains,there'sabigissueofcontaminationwithcontemporaryhumanDNA,"hesays.
12.Thisdoesn'tmeanthatallmuseumspecimensarefatallyflawed,notesPbo.TheNeanderthalfossilsthatwererecentlysequencedinhisownlab,forexample,hadbeenpartofamuseumcollectiontreatedinthetraditionalway.ButPboiskeentoseesamplesoffossilsfromeverymajorfindpreservedinlinewithGeigl'srecommendations—justincase.
Warmandwet
13.Geiglherselfbelievesthat,withcooperationbetweenbenchandfieldresearchers,preservingfossilsproperlycouldopenupavenuesofdiscoverythathavelongbeenassumedclosed.
14.Muchhumanculturaldevelopmenttookplaceintemperateregions.DNAdoesnotsurvivewellinwarmenvironmentsinthefirstplace,andcanvanishwhenfossilsarewashedandtreated.Forthisreason,Geiglsays,mostancientDNAstudieshavebeendoneonpermafrostsamples,suchasthewoollymammoth,oronremainsshelteredfromtheelementsincoldcaves—includingcavebearandNeanderthalfossils.
15.Betterconservationmethods,andafocusonfreshfossils,couldboostDNAextractionfrommoredelicatespecimens,saysGeigl.Andthatcouldshedmorelightonthestoryofhumanevolution.
(640wordsnature)
Glossary
Palaeontologists古生物学家
Aurochs欧洲野牛
Neanderthal(人类学)尼安德特人，旧石器时代的古人类。
Permafrost(地理)永冻层
Questions1-6
AnswerthefollowingquestionsbyusingNOMORETHANTHREEWORDSforeachanswer.
1.Howdidpeopletraditionallytreatfossils?
2.WhatsuggestionsdoGeiglandhercolleaguesgiveonwhatshouldbedonewhenfossilsarefound?
3.Whatproblemsmaybeposediffossilbonesarewashedon-site?NameONE.
4.WhatcharacteristicdofossilboneshavetomakethemsusceptibletobecontaminatedwithcontemporaryDNAwhentheyarewashed?
5.Whatcouldbebetterunderstoodwhenconservationtreatmentsareimproved?
6.Thepassagementionedseveralanimalspeciesstudiedbyresearchers.Howmanyofthemarementioned?
Questions7-11
Dothefollowingstatementsagreewiththeinformationgiveninthepassage?PleasewriteTRUEifthestatementagreeswiththewriterFALSEifthestatementdoesnotagreewiththewriterNOTGIVENifthereisnoinformationaboutthisinthepassage.
7.IntheirpaperpublishedintheProceedingsoftheNationalAcademyofSciences，GeiglandhercolleagueshaveshownwhatconservationpracticesshouldbefollowedtopreserveancientDNA.
8.ThefossilbonesthatGeiglandhercolleaguesstudiedareallfromthesameaurochs.
9.Geneticistsdon'thavetoworkonsite.
10.OnlynewlyexcavatedfossilbonesusingnewconservationmethodssuggestedbyGeiglandhercolleaguescontainancientDNA.
11.Paaboisstillworriedaboutthepotentialproblemscausedbytreatmentsoffossilsintraditionalway.
Questions12-13
CompletethefollowingthestatementsbychoosingletterA-Dforeachanswer.
12.“Thisinformation”inparagraph3indicates:
[A]ItiscriticaltofollowproperpracticesinpreservingancientDNA.
[B]ThebestwayofgettinggoodDNAistohandlefossilswithgloves.
[C]Fossilhuntersshouldwearhome-madehammerswhilediggingupbones.
[D]Manypalaeontologistsknowhowoneshoulddointreatingfossils.
13.ThestudyconductedbyGeiglandhercolleaguessuggests:
[A]thefactthatancientDNAcannotberecoveredfromfossilbonesexcavatedinthepast.
[B]thecorrelationbetweentheamountofburyingtimeandthatoftherecoveredDNA.
[C]thepaceatwhichDNAdegrades.
[D]thecorrelationbetweenconservationpracticesanddegradationofDNA.
Togetthejobstarted,____Ineedisyourpermission.
AccordingtoUKofficialstatistics,everyyearabout2000livesarelostthroughoccupationaldiseaseorinjury,about20,000majorindustrialinjuriesoccur(e.g.skullfracture,lossofsight)andthereareabout200,000injuriesresultinginaworkdisabilityof3daysormore.
Sitbackandreflecton______itisthatyoudobestandwhatyouenjoy.
