帮忙确认下这段英文中某些词的具体含义~

这篇文章的题目是：Adual-stagefunctionalmodellingframeworkwithmulti-leveldesignknowledgeforconceptualmechanicaldesign（我的译文：一个为概念上的机械设计服务的双重级水平设计的功能模型构架）

Ashasalreadybeenmentioned,thefunctionalobjectsstoredinthefunctionalobjectlibraryarerepresentedusinganobject-orientedscheme.WiththeinheritancemechanismfromOOtechnology,theclassesrepresentingmechanicalfunctionsare

organizedintothreetiersofahierarchy,i.e.fromgenericAshasalreadybeenmentioned,thefunctionalobjectsstoredinthefunctionalobjectlibraryarerepresentedusinganobject-orientedscheme.WiththeinheritancemechanismfromOOtechnology,theclassesrepresentingmechanicalfunctionsare

organizedintothreetiersofahierarchy,i.e.fromgenericfunctiontoembodimentfunction(thecompletelistofclassesde.ningthefunctionalobjectsaregiveninthe

Appendix).

Firsttier—topfunc:definingthegenericfunctionalobjects,whoseattributes(variables)andmethodsarerequiredbyallfunctionalobjects.

Secondtier—permfunc,asemfunc,manufunc,markfunc,mainfunc:definingfivebasictypesofmechanicalfunctions;namely,performancefunction,assemblyfunction,manufacturingfunction,marketingfunctionandmaintenancefunction(Dengetal.1998).Thesefunctionclassesinheritattributesand

methodsfromtheclasstopfunc.

Thirdtier—fmffunc:definingembodimentmechanicalfunctions,whichhaveassociatedphysicalstructures.Thisclassinheritsattributesandmethodsfromitsupperclasspermfunc.

请问：

1.我那实在不是很象样.文中（其他地方相同情境）曾多次出现knowledge这个词,翻译成什么好?理论?原理?知识好象不大通顺.

2.Secondtier中的“mechanicalfunctions;namely,performancefunction,assemblyfunction,manufacturingfunction,marketingfunctionandmaintenancefunction”是翻译成**功能,还是**函数!

3.如果有可能的话,请帮忙全部翻译下,一段也行~