简介:Indownlinkcoordinatedmulti-point(CoMP)system,fullcooperationisalwaysnotapplicableinrealworldbecauseofitshighrequestinthebackhaul.Todealwiththisproblem,clusteringdecisionismadetoprocesstransmission.Inthispaperclusteringmethodsbasedonthemetricsignal-to-leakage-plus-noise(SLNR)isproposed.Inaddition,userschedulingschemesbasedonSLNRisalsoputuptomaketheschedulingsetaslargeaspossible.Simulationresultsshowthattheproposedclusteringmethodsnotonlyreducethedatasharingamongthecooperatingbasestations(BSs),butalsoimprovethesystemthroughputcomparedwiththetraditionalclusteringmethodsbasedonchannelstrength.
简介:Orthogonalfrequencydivisionmultiplexing(OFDM)whichhasbeenadoptedinthelong-termevolution(LTE)systemcanimprovethesystemcapacityobviously.However,italsobringsaboutsevereinter-cellinterference(ICI)forcell-edgeusers(CEUs).Totacklethisproblem,multi-userselectionandpowercontrol(MuS-PC)isproposedasanefficientschemeinuplinkcoordinatedmulti-pointmulti-usermulti-inputmulti-output(CoMP-MU-MIMO)transmission/reception.Thispaperjointlyconsidersuser’ssignaltointerferenceplusnoiseratio(SINR)andproportionalfairness(PF)tomaximizethetotalchannelcapacityinmulti-userselectionbyformulatingapenaltyfunction.Tosimplifythepenaltyfunction’scomputation,particleswarmoptimization(PSO)algorithmisintroduced.Inaddition,powercontrolisadoptedtomaximizeoverallenergyefficiency.SimulationresultsdemonstratethattheMuS-PCschemecannotonlyobtaintheoptimaltotalchannelcapacitywhileguaranteeeachuser’squalityofservice(QoS)andPF,butalsolargelyreducecomputationalcomplexityandimproveenergyefficiency.Asaresult,thepoorcommunicationqualityofCEUscanbeenhanced.
简介:Coordinatedmulti-pointtransmission/reception(CoMP)wasproposedcurrentlyasaneffectivetechnologytoimprovecell-edgethroughputinnext-generationwirelesssystems.Mostoftheexistingworkdiscussedclusteringmethodsmostlytomaximizetheedgeuserthroughputwhileneglectingtheproblemofenergyefficiency,suchasthosealgorithmclusteringbasestations(BSs)ofbetterchannelconditionandBSsofworsechannelconditiontogether.Inaddition,BSsusuallyincreasethetransmitpowertoachievehigherthroughputwithoutanyconsideringofinterferencecausedtootherusers,thatmayresultinenergywaste.TheauthorsfocusonthethroughputmaximizingproblemwhilefullyconsideringenergysavingprobleminCoMPsystems.Acoefficientisdefinedtodescribethefitnessofclusters.Thenasub-carrierallocationalgorithmwithclusteringmethodisputforwardforCoMPdownlink,whichcansavethetransmitpowerofBSandincreasethethroughput.Furthermoreapowerallocationschemeisproposedbasedonnon-cooperationgame;inwhichthetransmitpowerisdecreasedbyBSsgenerallytoreachtheNashequation(NE).Simulationshowsthattheproposedsub-carrierallocationschemeandpowerallocationalgorithmarebetterthantheexistingonesonusers’throughputwhileconsumesmuchlessenergy.
简介:摘要:遗传学研究生物的遗传、变异及其规律;人类对遗传的研究从性状开始的,遗传因子的发现到证明遗传密码的存在并破译遗传密码的过程是人们认识遗传的物质基础并揭示遗传规律的过程,在此过程当中遗传基因这个抽象的概念在思维上和实质上逐渐接近染色体、DNA;然后科学家们证明基因是有遗传效应的DNA的片段,从此基因不再是抽象的概念,以后人们又发现性状的表达离不开蛋白质(酶)合成,于是科学家们推测并证明基因通过指导蛋白质的合成而控制生物的性状,于是最终孟德尔的假设得到了科学解释。人民对遗传学的研究是实质上揭示基因表达的过程,这是生物学史上的重大发现。
简介:目的比较HBVS基因与HCVC基因真核表达质粒融合基因免疫与联合基因免疫的效果,为HBV和HCV融合基因疫苗研究奠定基础。方法将同时含HBVS基因与HCVC基因的真核表达质粒SCpcDNA3.1、含HBVS基因真核表达质粒SpcDNA3.1、含HCVC基因真核表达质粒CpcDNA3.1分别免疫小鼠;将SpcDNA3.1+CpcDNA3.1联合免疫小鼠。ELISA法检测血清抗HBs和抗HCV。结果无论是抗HBs和抗HCV阳转出现的时间、阳转率和体液免疫应答强度,融合基因免疫都优于联合基因免疫:融合基因免疫的抗HBs的应答强度低于SpcDNA3.1质粒的免疫,抗HBc的应答强度高于CpcDNA3.1质粒的免疫。结论HCVC基因或其表达产物对HBVS基因或抗原的表达和提呈有抑制作用;HCVC基因与HBVS基因相融合,更有利于HCV核心蛋白的提呈。
简介:目的探讨玻璃酸钠注射液对膝骨关节炎(KOA)患者的治疗效果,及其对关节液中软骨寡聚基质蛋白(COMP)及基质金属蛋白酶-13(MMP-13)浓度的影响。方法选取自2013年1月至2014年1月KOA患者100例,随机分为对照组和观察组,每组各50例。两组患者均接受关节腔内药物注射治疗,对照组患者给予糖皮质激素,观察组患者给予玻璃酸钠,两组患者均治疗1个疗程。评价两组患者治疗后的疗效,分别于治疗前后采用美国特种外科医院膝关节评分(HSS)标准对患者进行评分,检测两组患者治疗前后关节液中COMP、MMP-13的浓度,对收集到的数据进行统计学分析。结果两组患者治疗前后的HSS膝关节评分存在明显差异,治疗后HSS膝关节评分较治疗前明显增加(P〈0.05),且观察组增加幅度更大;两组患者治疗后的总有效率分别为76.O%、92.0%,观察组总有效率明显高于对照组(P〈0.05);治疗前,两组患者关节液中COMP、MMP-13浓度比较差异无统计学意义(P〉0.05);治疗后,观察组关节液中COMP、MMP-13浓度分别为(3.2±1.3)ng/ml、(352.7±48.4)μg/L,对照组关节液COMP、MMP.13浓度分别为(3.8±1.4)ng/ml、(416.4±52.5)μm,两种物质的表达水平均较治疗前明显降低(P〈0.05),且观察组降低幅度更为显著,治疗后的COMP、MMP-13浓度与对照组比较差异有统计学意义(P〈0.05)。结论玻璃酸钠关节腔内注射治疗KOA的疗效确切,总有效率明显提高,且治疗后关节液中COMP、MMP-13的分泌表达受到明显抑制,有助于促进软骨的修复,对病情的延缓及生活质量的提高十分有利。