简介:1IntroductionH-matriceshaveimportantroleinnumericalanalysisandmatrixtheory,etc.Inthispaper,severalpracticalcriteriaforH-matricesareobtained,towhichthematrixisnotnecessarybeadiagonallydominantmatrix,andthenumbersofrowswhicharenotdiago-naldominantcanben-1.Weintroducetheconceptofα-diagonallydominantmatrix,andbyusingtheconcepttoinvestigateH-matrices.
简介:摘要:厚板H型钢焊接时,由于焊接热输入量大,焊后很容易变形。在制造过程中主要的变形有翼缘角变形、弯曲变形、轴线扭曲变形,如不采取措施将严重影响结构质量。因此,焊接变形控制显的尤为重要。
简介:Alooplessgraphonnverticesinwhichverticesareconnectedatleastbyaandatmostbybedgesiscalleda(a,b,n)-graph.A(b,b,n)-graphiscalled(b,n)-graphandisdenotedbyKbn(itisacompletegraph),itscomplementbyKbn.Anonincreasingsequencep=(d1,…,dn)ofnonnegativeintegersissaidtobe(a,b,n)graphicifitisrealizablebyan(a,b,n)-graph.Wesayasimplegraphicsequencep=(d1,…,dn)ispotentiallyK4—K2[K2-graphicifithasaarealizationcontaininganK4—K2[K2asasubgraphwhereK4isacompletegraphonfourverticesandK2[K2isasetofindependentedges.Inthispaper,wefindthesmallestdegreesumsuchthateveryn-termgraphicalsequencecontainsK4—K2[K2assubgraph.
简介:本文着重研究了H.265编码的高清视频质量评价方法,以用于未来测试H.265编码器的性能。根据ITUVQEG的最新研究进展,介绍了高清视频的主观评价和客观测量方法,并且分析了目前已有的客观测量技术的主要实现方法和与主观评价方法相关度的结果,最后给出H.265编码视频质量测量技术的发展建议,并指出针对H.265编码器的测试,实验室环境,全参考的方法是首选,而无参考的方法是研究趋势。
简介:TheauthorsconsidertheextendedHeckegroupsH(λq)generatedbyT(z)=-1/z,S(z)=-1/(z+λq)andR(z)=1/-zwithλq=2cos(π/q)forq≥3aninteger.Inthispaper,theevensubgroupHe(λq),thesecondcommutatorsubgroupH"(λq)andtheprincipalcongruencesubgroupsHp(λq)oftheextendedHeckegroupsH(λq)arestudied.Also,relationsbetweenthemaregiven.