简介:给出了Neuman-Sándor平均关于第二类反调和平均与算术平均的最佳不等式,所得结论加强了已知结果。
简介:本系统是一个基于可编程控制器(PLC)西门子S7-300的旋转木马控制系统,它通过S7-300系列PLC内部计时器的使用,实现旋转木马的一键式启动,并能保证在任何情况下紧急停止。本文所述的旋转木马控制系统,就是PLC在民用消费领域的又一应用。
简介:Background:Althoughemergingresearchisdemonstratingthepotentialhealthimpactofexergaming,investigationshaveprimarilybeenconductedinlaboratorysettingsamongsmallsampleswithshort-terminterventions.Informationontheeffectivenessofexergaminginunderservedchildren’sobjectivephysicalactivity(PA)inpopulation-basedsettingsisalsoscarce.Moreover,mostempiricalstudieshaveonlyincluded1typeofexergameintheintervention.Therefore,thisstudy’spurposewastoinvestigatethelong-termimpactofamultigameexergaminginterventionamongunderservedchildrenintegratedwithinschoolcurricula.Specifically,thisstudyexaminedtheeffectofexergamingonchildren’saccelerometer-determinedsedentarybehavior(SB),lightPA,moderate-to-vigorousPA(MVPA),andenergyexpenditure(EE)over2yearsascomparedwithregularphysicaleducation(PE)classes.Methods:Atotalof261second-andthird-gradechildren(134girls,127boys;meanage8.27years)wererecruitedfrom2Texaselementaryschools.Children’spre-test3-daySB,lightPA,MVPA,andEEatschoolwereassessedinthefallof2012.Participantswereassignedto1of2groups:(1)exergaming/PEgroup(125minweeklyofexergaming-basedPAprogram)and(2)comparisongroup(125minweeklyofPE).PA(SB,lightPA,andMVPA)andEEoutcomevariableswereassessedagainin2013(post-test)and2014(follow-up).Results:SignificanttimeeffectswereobservedforSB(F(1,162)=25.0,p<0.01,η~2=0.14),lightPA(F(1,162)=9.6,p<0.01,η~2=0.06),andMVPA(F(1,162)=6.2,p=0.01,η~2=0.04)butnotforEE(F(1,162)=0.63,p>0.05,η~2=0.004).Subsequentpairwisecomparisonsrevealedsignificantincreasesfrompre-topost-testforlightPA(p<0.01),MVPA(p<0.01),andEE(p=0.02)withnochangesinSB(p>0.05).Conversely,significantdecreasesoccurredinlightPA(p<0.01)frompost-testtofollow-upwithnodifferencesseeninMVPA(p=0.08)andEE(p=0.06)overthesametimeperiod.Asignificantincreasewasseen,however,forSBfrompost-testtofollow-up.Conclusion:Exergami