简介:【摘 要】“图形与几何”是小学数学四大领域之一,对培养学生的空间观念起着不可替代的作用。教师如何帮助小学生构建空间观念,提高空间想象能力,是此领域课堂教学重要的出发点与归宿。本文以《长方体和正方体》单元教学为例,借助“长方体和正方体”这两种最基本的立体图形,阐述“线、面、体”三者关系,通过动手操作、数形结合、想象推理等方法,探索了空间观念培养的有效学习策略。
简介:最接近于现实的转会系统、最完整的阵型系统、最完善的球员数据库、基于这些特性,2003年11月21日,CM03/04(ChampionshipManager03/04,中译冠军足球经理)正式版在众多球迷兼游戏迷的期待下终于上市。CM在中国已经是这部作品是Sigames和Eidos(Eidos曾是曼城队的胸前广告赞助商)分
简介:
简介:Background:Athletes,coaches,sportpsychologypractitioners,andresearcherssuggestthatmentaltoughnessrepresentsanimportantconstructthatisassociatedwithathleticperformance.Unfortunately,theabsenceofreal-worldperformanceasadependentvariablehaslimitedourabilitytosubstantiatethisclaim.Theconcernofalackofecologicallyvalidmeasuresofsportsperformancemightbeaddressedbyexaminingtherelationshipbetweenmentaltoughnessandsportsperformanceusingastandardizedmeasureofpersonalbest(PB)triathlontimeandavalidatedunidimensionalmeasureofmentaltoughness.Methods:Threehundredandsixteentriathletescompletedthe8-itemmentaltoughnessindex(MTI),reportedtheirage,andprovidedaPBOlympicdistancetriathlontimeandthetotalnumberoftriathlonstheyhadcompletedtodate.Giventhatmalesaretypicallyquickerthanfemales,astandardizedtimewascalculatedbydividingthePBbythecurrentOlympicrecordforgender;wealsohypothesizedthatmoreexperiencedtriathleteswouldreportquickerPBtimesbecauseofgreaterfrequencyanddurationoftraining.Oncewehadcontrolledforgenderandexperience,wepredictedthatmentaltoughnesswouldbenegativelyassociatedwithtriathlontimeandthesizeoftherelationshipwouldbeofamoderatemagnitude.Results:Resultsrevealedsmall-tomoderate-sizednegativerelationshipsbetweenbothcompletednumberoftriathlonsandmentaltoughnesswithstandardizedPBtime.Conclusion:ThehierarchicalregressionanalysisshowedthatmentaltoughnessprovidedauniquecontributiontothevariabilityinstandardizedOlympictriathlonPBaftercontrollingforthetotalnumberoftriathlonscompleted.