简介:Asusersincreasinglybefriendothersandinteractonlineviatheirsocialmediaaccounts,onlinesocialnetworks(OSNs)areexpandingrapidly.Confrontedwiththebigdatageneratedbyusers,itisimperativethatdatastoragebedistributed,scalable,andcost-efficient.Yetoneofthemostsignificantchallengesaboutthistopicisdetermininghowtominimizethecostwithoutdeterioratingsystemperformance.Althoughmanystoragesystemsusethedistributedkeyvaluestore,itcannotbedirectlyappliedtoOSNstoragesystems.Andbecauseusers'dataarehighlycorrelated,hashstorageleadstofrequentinter-servercommunications,andthehighinter-servertrafficcostsdecreasetheOSNstoragesystem'sscalability.Previousstudiesproposedconductingnetworkpartitioninganddatareplicationbasedonsocialgraphs.However,datareplicationincreasesstoragecostsandimpactstrafficcosts.Here,weconsiderhowtominimizecostsfromtheperspectiveofdatastorage,bycombiningpartitioningandreplication.Ourcost-efficientdatastorageapproachsupportsscalableOSNstoragesystems.Theproposedapproachco-locatesfrequentlyinteractiveuserstogetherbyconductingpartitioningandreplicationsimultaneouslywhilemeetingload-balancingconstraints.Extensiveexperimentsareundertakenontworeal-worldtraces,andtheresultsshowthatourapproachachieveslowercostcomparedwithstate-of-the-artapproaches.ThusweconcludethatourapproachenableseconomicandscalableOSNdatastorage.
简介:Here,wereportthesynthesisofhardcarbonmaterials(RH)madefromnaturalricehuskthroughasinglepyrolysisprocessandtheirapplicationasananodeinsodium-ionbatteries.ThestudiesshowthattheelectrochemicalpropertiesofRHsareaffectedbythetreatmenttemperatures,whichdeterminethematerialsmorphology,inparticular,theirdegreeofgraphitizationandextentofcontinuouschannels(nanovoids).Thelatterareaccessibletosodiumionsandsignificantlycontributetochargestoragecapacityoftheproducedanodes.TheRHsobtainedat1600°Cdeliverthehighestreversiblecapacityof276mAhg-1mainlyduetoinsertionofsodiumionsintothenanovoids.Thisworkdeepensthebasicunderstandingoftheinfluenceofthecarbonizationtemperatureonthesodiumstoragemechanism.
简介:【摘 要】目的:研究浅谈院前急救患者搬运方法。方法:对 2017年 5月 -2018年 5月被我院消化科收治的 90例病进行研究,将其以随机分组的原则分为实验组与对照组,实施组在抢救时由分管抢救的责任护理人员统一指导将病患由平车至床上搬运的方法,而对照组未给予特殊要求,依照病患的自理能力由家属或医护人员协助搬运,比较两组病患的急救情况。结果:就实验组与对照组病患的并发再次出血情况来看,实验组再次出血例数为 3例,占本组总例数的 6.67%,对照组再次出血例数为 9例,占本组总例数的 20.00%,差异显著,统计学有对比意义 P< 0.05;对比实验组与对照组病患的护理满意度情况,实验组护理总满意度为 93.33%,对照组为 82.22%,差异显著,统计学有对比价值 P< 0.05。结论:院前急救过程中对病患实施有效的搬运措施可以防止意外问题的产生,尤其对上消化道出血病患来说更能防止二次出血的风险,具有临床推广价值。