Blockchain 区块链

BLOCKCHAINBY邓斌斌Whatisblockchain?Eachtransactioninthesetthatmakesupablockisfedthroughaprogramthatcreatesanencryptedcodeknownasthehashvalue.HashvaluesarefurthercombinedinasystemknownasaMerkleTree.Theresultofallthishashinggoesintotheblock’sheader,alongwithahashofthepreviousblock’sheaderandatime-stamp.Theheaderthenbecomespartofacryptographicpuzzlesolvedbymanipulatinganumbercalledthenonce.Onceasolutionisfoundthenewblockisaddedtotheblockchain.Whataretheapplicationofblockchain?DistributionShoppingTrustInternetTransactionSecurity……分布式账本添加幻灯片标题-1DECENTRALIZATION去中心化Ifyou'reahackerYouwillAttack?BANKAcentralizedledgertracksassetmovementswithinthefinancialsystembetweeninstitution.Adistributedledgereliminatestheneedforcentralauthoritiestocertifyassetownership.Institutionstocutdownonfraudandmanipulation.TraditionalDATAGLOBALIZATIONBlockchainSecurityThankyou!BlackTechnologyinAmericanelection毛承蔚Paylessbutgainmore？？！•Thankstobigdatahiahiahia~~~~~~NateSilver◆In2008，Itpredicted49ofthe50stateselectionscorrectly.◆In2012，Itpredictedall50stateselectionscorrectly.GOODJOB!!whoisthenext?Aelectionwithstrongbigdatagene.Inthiselection,thetechnologyteamthatservedMrsClinton'selectionhasmorethan50people,theequivalentofasmallsiliconvalleytechstart-up.HillaryClinton,$240million.•李存益-AwonderfulwaytoidentifythelevelandimportanceofawepageThebasicalgorithm:1.everywebpagewillgetthesamePageRankatfirst2.Executethefollowingcycle:EachpageassignsitscurrentPageRankequallytotheoutwardlinksonthispage,sothateachlinkgetsthecorrespondingPageRank.Foreachcycle,thenewPageRankisobtainedbysummationofallthePageRankthatispassedininwardlinksofthispage.3.Afterseveralcycle,thePageRankofeverywebpagewon'tchangeanymore.AndthemorehigherthePageRank,themoreimportantthewebpage.L:thenumberofoutwardliknksPR:thePageRankinthiscycleq:Dampingfactor:theprobabilitythatauserreachesawebpageandcontinuestobrowsebackwardsatanytime.Advantage:Itisastaticalgorithmwhichisindependentofthequery.AndthePageRankofallwebpagesisobtainedbyofflinecalculation.Iteffectivelyreducetheamountofcomputationinonlinequery,greatlyreducethequeryresponsetime.disadvantage:People'squeriesalwayshavethematicfeatures.ButPageRankignoresthematicrelevance,resultinginthereductionofthecorrelationandthematicforresults.