简介:一张图的一个顶点被说统治它的邻居的本身和所有。图G的一个双统治集合是G的顶点的集合D,以便G的每个顶点被D的至少二个顶点统治。图G的双支配数字是G的一个双统治集合的最小的集的势。为图G=(V,E),如果V(G)\D的每个顶点在D有至少二位邻居,子集DV(G)是一个2-dominating集合,当如果,统治G的集合是2-outer-independent的时另外集合V(G)\D是独立的。G的2-outer-independent支配数字是统治G的集合的2-outer-independent的最小的集的势。这份报纸加一个与双支配数字平等者描绘所有树到2-outer-independent支配数字。
简介:At-hyperwheel(t≥3)oflengthl(orW(t)lforbrevity)isat-uniformhypergraph(V,E),whereE={e1,e2,...,el}andv1,v2,...,vlaredistinctverticesofV=∪eii=1lsuchthatfori=1,...,l,vi,vi+1∈eiandei∩ej=P,j∈/{i1,i,i+1},wheretheoperationonthesubscriptsismodulolandPisavertexofVwhichisdifferentfromvi,1≤i≤l.Inthispaper,theminimumcoveringproblemofMCλ(3,W(3)4,v)isinvestigated.DirectandrecursiveconstructionsonMCλ(3,W(3)4,v)arepresented.Thecoveringnumbercλ(3,W(3)4,v)isfinallydeterminedforanypositiveintegersv≥5andλ.
简介:BackgroundPreviousstudieshavesuggestedthatpatientswithlowendothelialprogenitorcell(EPC)countsandimpairedendothelialcolonyformingactivityhaveahigherincidenceforcardiovasculareventscomparedtopatientswithhighEPCcountsandfavorablecolonyformingactivity.ThepathophysiologicalbasisforthisfindingmaybeaninsufficientendothelialcellrepairbyEPC.TheobjectiveofthisstudywastodeterminewhetherthenumberofEPCsinperipheralbloodwasassociatedwiththepresenceandseverityofangiographicstenosisinpatientsofthelatephaseafteracutemyocardialinfarction(AMI).MethodsOnehundredandonepatientsundergoingcardiaccatheterizationinourhospitalwereenrolledinthestudy.ThenumberofcirculatingEPCswasmeasuredbyafluorescent-activatedcellsorter(FACS).Patientswithacutecoronarysyndromeswereexcluded.ResultsComparedwithpatientswithnormalcoronaryartery,thenumberofcirculatingEPCswassignificantlyreducedamongpatientsinthelatephaseafterAMI(P<0.01).Wealsofoundthatcomparedwiththecontrolgroup,thenumberofEPCsofsingle-vesselstenosisgroupandmulti-vesselstenosisgroupweresignificantlyreduced(P=0.005;P=0.001).ConclusionsThenumberofEPCsintheperipheralbloodisdecreasedinpatientsofthelatephaseafterAMI.TheEPCsnumbercorrelatedwithangiographicstenosisseverity,whichsuggeststhatendothelialinjuryinthedeficientcirculatingEPCsmayaffecttheseverityoftheheartdisorderandtheclinicalpresentations.
简介:图G的导致的路径数字(G)被定义为G的顶点集合能被划分成的子集的最小的数字以便每个子集导致一条路径。Broere等。如果G是顺序n的一张图,证明了那,那么$\sqrtn\leqslant\rho\left(G\right)+\rho\left({\barG}\right)\leqslant\left\lceil{\tfrac{{3n}}{2}}\right\rceil$。在这份报纸,我们描绘图G为哪个$\rho\left(G\right)+\rho\left({\barG}\right)=\left\lceil{\tfrac{{3n}}{2}}\right\rceil$,在$\rho\left(G\right)上改进更低的界限+\rho\left({\barG}\right)$在一个当n是一个奇怪的整数的平方时,并且为$\rho\left(G\right)决定最好的可能的上面的界限+\rho\left({\barG}\right)$当既不G也不$\barG$孤立顶点时。
简介:Inordertoraisetheprecisionofstresswaveimagingtechnology(SWIT),undertheconditionsofdifferentareaandoutlineofsimulatedcavitydefectsintimberdiscsofspruce,differentnumberofusedsensors,therelationshipbetweenimaginggraphdefectsandrealdefectsisstudied.Theresultshows:SWITcandisplaygraphofdefects,theprecisionofimaginggraphrelatestorateofrealdefectareaandareaofthetestedwoodcrosssection,thenumberofusedsensorsandoutlineshapeofthedefects.Whentheraterisesfrom1.6%to25.0%,therelativeerrorofgraphdefectareaandrealdefectareadropsfrom22.6%to9.7%.Whenthenumberofusedsensorsisfrom6to24,thegraphofSWITcanshowtheexistenceofrealdefect.ButthenumberofsensorsusedinfluencestheprecisionofSWIT.Outlineshapeofdefectshascertaineffectondetectionofdefects.Undertheconditionofthesamedefectarea,thedefectsoflongandnarrowshapeareeasytobeshownbygraph.Therelationerrorofdefectareaofsuborbicularshapeissmallerthanthatoflongandnarrowshape.