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简介：Inordertoensurethehighestsafetyrequirements,nuclearpowerplantstructures(thecontainmentstructures,thefuelstoragesandtransportationsystems)shouldbeassessedagainstallpossibleinternalandexternalimpactthreats.Theinternalimpactthreatsincludekineticmissilesgeneratedbythefailureofhighpressurevesselsandpipes,thefailureofhighspeedrotatingmachineriesandaccidentaldrops.Theexternalimpactthreatsmaycomefromairbornemissiles,aircraftimpact,explosionblastandfragments.Theimpacteffectsofthesethreatsonconcreteandsteelstructuresinanuclearpowerplantarediscussed.Methodsandproceduresfortheimpactassessmentofnuclearpowerplantsareintroduced.Recentstudiesonpenetrationandperforationmechanicsaswellasprogressesondynamicpropertiesofconcrete-likematerialsarepresentedtoincreasetheunderstandingoftheimpacteffectsonconcretecontainmentstructures.

简介：曾几何时，汽车犹如你封闭的避难所，可以与车外的世界完全隔离?曾几何时，你还只有坐在露天的看台上才能得知比赛的进展?的确，数字时代的新手段给我们带来了便捷、高效和即时的满足感。然而，这是要有代价的：我们的科技越进步。我们就越暴露自己。不管我们从中受益多少，下面的故事就提醒了我们：不管我们在哪，不论我们做什么，都可能有人或者有东西在监视我们。

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简介：Thewirelessapplicationprotocol(WAP)protocolisnowtheleadingstandardforinformationservicesonwirelessterminalslikedigitalmobilephones.BytheuseofWAP,wirelessdevices,likemobilephones,arepossiblyinfectedwithvirusandworms.Thoughuptonowthereisnosuchattack,astheusageofscriptlanguagesincreases,thereisachanceofmaliciouscodeinjection.ThispaperdiscussesthethreatswithcurrentWAPprotocol,andhowchangesintheprotocolandtheincreaseinitsusagewillenableentryofrealviruses.Futurethreatscenariosarepresentedalongwithsuggestionstoavoidtheseproblems.

简介：Background:Acaciamangium,afast-growingtreenativetopartsofIndonesia,PapuaNewGuineaandAustralia,hasbeencultivatedoutsideitsnativeenvironmentandintroducedintohumidtropicallowlandregionsofAsia,SouthAmericaandAfricaoverthelastfewdecades.Itisamultipurposetreeusedinagroforestry,forestryandforrestorationofdegradedlands.Itisalsohighlyinvasiveinmanyregionswhereithasbeenintroducedoutsideitsnativerange.Thispaperreviewsevidenceofitsobviousbenefitsanditsnegativeimpactsonbiodiversity.Methods:AliteraturereviewonAustralianacaciasandespeciallyonA.mangiumwasundertakentohighlightbothbenefitsandthreatsassociatedwiththeirincreasingworldwideuseoutsidetheirnativeranges.Results:ThroughN2fixedfromtheatmosphere,A.mangiumimprovessoilfertility,especiallybyincreasingNstatusandsoilCaccretionwhenintroducedtoN-limitedareas;itthushasthepotentialtorestorenutrientcyclingindegradedsystems.Nostudieshave,however,beendonetoassesstheeffectivenessofA.mangiuminrestoringbiodiversityofdegradedlands.MostAustralianacaciashavetraitsthatfacilitateinvasiveness,and23specieshavebeenrecordedasinvasivetodate.A.mangiumhasbeenreportedasinvasiveinAsia,Indonesia,PacificIslands,IndianOceanIslands,southernAfricaandBrazil.ResearchonotherinvasiveAustralianacaciasinseveralpartsoftheworldhaselucidatedthetypesofimpactsthatarelikelyindifferenttypesofecosystemsandkeyoptionsformitigatingimpacts.Conclusions:A.mangiumhasthepotentialtorestorenutrientcyclingindegradedsystems,butishighlyinvasivewhereveritisplanted.Manypartsoftheworldhavealargeinvasiondebtforthisspecies.Experiencewithotherinvasiveacaciasaroundtheworldsuggestsasuiteofinterventionsthatcouldbeusedtoreduceinvasionsandmitigateimpacts.Carefulriskassessmentsshouldbeundertakenpriortoanynewplantingsofthisspecies.

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简介：决定经常在造的基础结构上对爆炸强风负担关于保护的措施的需要或程度被需要。决定支持分析考虑命运风险和以每生命在风险减小上花的期望的费用表示的保护的措施的划算为对基础结构的恐怖主义者威胁节省了。分析对基础结构的任何条款适用，但是在这，纸被用于从造上釉损坏的门面产生的伤亡。风险可能与在量的安全目标形式的风险接受标准相比。保护的措施的风险可接受程度和划算包括保护的措施的费用，攻击概率，在风险的减小由于保护的措施，在成功的恐怖主义者上有条件的命运的概率暴露的个人攻击并且数。