简介：通用技术课程学习中的实践活动,它主要指分析与解决有关实际技术问题的思维活动或技术操作活动。所谓载体,在通用技术课程中,主要指技术事物或技术产品,即实践活动的对象。贯彻生活性原则是注重强化学生的生活技术意识,提倡简约性原则是注重促进学生对技术思想与方法的领悟与运用,遵循基础性原则是注重立足于学生的可行性实践,而渗透创造性原则是注重培养与发展学生的创造素质。

简介：Thebundleofthe2-formson6-manifolddecomposesintothreesubbundlessuchthatΛ2（R6）=Λ21⊕Λ26⊕Λ28withdimensions1,6and8,respectively.Theselfandantiselfdualitysolutionsofthe2-forms,calledΦ-duality,arehandledandthesesolutionsshowthattheantiselfdualgaugefieldsliveonthesubbundlesΛ21andΛ26whiletheselfonesequationsonΛ28.AlsothesolutiononΛ21presentsaflatconnection.Inaddition,thecurvaturesoftheconnectionsonΛ26andΛ28haveTr[F3]=0,andsothetopologicalinvariantsdeterminedbytheChernclasses,i.e.topologicalcharge,consistonlyonthesecondChernclass.Intheresultofthiscase,theantiselfandselfΦ-dualgaugeinvariantLagrangiansofdefinedonbothsubbundlesareboundedbythesametopologicalcharge.Also,onegivesaquantizationcasetoberelatingtotheinstantonnumber.