学科分类
/ 25
500 个结果
  • 简介:Traditionally,SQLquerylanguageisusedtosearchthedataindatabases.However,itisinappropriateforend-users,sinceitiscomplexandhardtolearn.Itistheneedofend-user,searchingindatabaseswithkeywords,likeinwebsearchengines.Thispaperpresentsasurveyofworkonkeywordsearchindatabases.ItalsoincludesabriefintroductiontotheSEEKERsystemwhichhasbeendeveloped.

  • 标签: 关系数据库 关键字搜索 隐藏web 信息系统集成
  • 简介:摘要:作为基础教育的低年级数学教学应以培养学生的数学核心素养为教学的终极目标。那么,学生的数学核心素养必须从低年级开始培养,把它贯穿于整个数学教学过程之中。 本文通过四个方面对其进行论述。

  • 标签: 小学数学 核心素养 培养
  • 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

  • 标签:
  • 简介:RMBexchangerateTheexchangerateofRenminbi,theChinesecurrency,witnessedanappreciationofaroundsixpercenttooneU.S.dollarthisyear.OnDecem-ber13,thecentralparityratestoodatRMB7.3568againstonedollar,accordingtotheChineseForeignExchangeTradingSystem,breakingthe7.36mark.

  • 标签: 经济状态 对外贸易 中国 2007年
  • 简介:~~

  • 标签:
  • 简介:

  • 标签:
  • 简介:~~

  • 标签: