简介:图的染色是图论中非常重要的研究课题,图的染色的基本问题即是确定各种染色法的色数.图G的邻点可区别I-全染色是一个新的染色概念,对二幂图P2n的邻点可区别I-全染色问题进行了研究,从其结构特点出发,运用构造法和色调整技术,给出了P2n的邻点可区别I-全染色法,得到了P2n的邻点可区别I-全染色数.
简介:Inaclassicallayoutprocessofafanthequantityoflossesisestimatedasasumandexpressedintheoverallefficiencyrateη.Howeverthecharacteristicofthepressurerise,thelossesandtheefficiencyratebesidethedesignpointisnotknown.Againstthisbackgroundanumericalmodelwasdevelopedtocalculatequantitativevaluesofoccurringlossesatradialfanimpellersatanearlystageinthedesignprocess.Itallowstoestimatethepressureriseandefficiencyrateofagivenfangeometryatandbesidethedesignpoint.Thephysicsoflossesaredescribedinliterature,butobtainingquantitativevaluesisstillachallenge.Ascommoninhydraulictheorythelossesarecalculatedwithanalyticformulassupportedbycoefficientsandefficiencyrates,whichhavetobedeterminedempirically.Thispapershowsthemethodhowtodeterminethecoefficientsforagivenradialfan.Thereforearepresentativeradialfanwithbackwardcurvedbladeswasdesignedinreferencetoclassicaldesignguidelines.PerformancemeasuringwasdoneconformtoISO5801.Theflowwascalculatedat8differentoperationpointsusingCFDmethods.TheRANSequationsaresolvedbyusingtheSST-k-omegaturbulencemodel.Theflowdomainconsistsofonebladesectionincludinginletchannelandoutflowchamber.Spatialdiscretizationisdonebyablock-structuredmeshofapprox.1.8millioncells.Performancedatashowaverygoodagreementbetweenmeasurementandcalculation.
简介:Tooptimizetheprocessparameters,itisnecessarytoexactlypredictfailuremodesduringdeepdrawingofcoatedmetalsheets,wheretwomainfailureformsarefractureandwrinkling.Inthispaper,finiteelementsimulationsbasedoncontinuousdamagemechanicswereusedtostudythefailurebehaviorduringacylindricaldeepdrawingofmetalsheetswithnickelcoating.Itisshownthattakingtheeffectofblankholderforceintoaccount,thesetwofailuremodescanbepredicted.Thesimulationresultsarewellconsistentwiththatobtainedfromexperiments.
简介:摘要目的探讨p16蛋白和p27蛋白在宫颈癌中的表达及其临床意义。方法采用免疫组化SP法检测60例宫颈癌组织,51例宫颈上皮内瘤样病变(CIN)组织和30例正常宫颈组织中p16蛋白和p27蛋白的表达,并分析它们与宫颈癌临床病理因素的关系。结果宫颈癌组织中p16的阳性表达率(96.72%)明显高于CIN组(43.13%)和正常宫颈组(26.6%),P<0.01;表达水平与间质浸润、组织病理分级、有无淋巴结转移有关(P<0.05);与临床分期、组织类型无关(P>0.05)。p27蛋白在宫颈癌组织中的阳性表达率(24.59%)明显低于CIN组(65.1%)和正常宫颈组(89.7%),P<0.01;其表达水平与组织病理分级、间质浸润、淋巴结转移有关(P<0.05)。结论p16蛋白过表达、p27蛋白低表达与宫颈癌的发生发展有关,联合检测p16与p27蛋白对于早期诊断宫颈癌以及判断其侵袭转移潜能及预后有一定参考价值。