At present, one of the important tasks of the ongoing college English teaching reform is to reform the traditional teaching mode,establishing the computer-based multimedia English teaching model. Based on the construc...At present, one of the important tasks of the ongoing college English teaching reform is to reform the traditional teaching mode,establishing the computer-based multimedia English teaching model. Based on the constructivist theory and the second language acquisi-tion theory, teachers who adopt the new teaching model should play multiple roles to maximize the teaching effect, being not only thecourse designer, organizer, but also the guide, helper and facilitator in the process of teaching students to construct knowledge and be en-gaged in classroom activities as well.展开更多
针对现有RBAC(Role-Based Access Control)委托授权模型存在的不足:其一,没有有效地实现细致委托粒度;其二,权限传播没有得到很好的控制,给出一种基于映射机制的细粒度角色委托模型RDBMPM(Fine-Grained Role Delegation Model Based Per...针对现有RBAC(Role-Based Access Control)委托授权模型存在的不足:其一,没有有效地实现细致委托粒度;其二,权限传播没有得到很好的控制,给出一种基于映射机制的细粒度角色委托模型RDBMPM(Fine-Grained Role Delegation Model Based Permission Mapping Mechanism),该模型基于向量化与度量化算子的复合运算,提出了度量角色的概念,并以其为授权粒度对委托约束机制进行讨论,增强了权限传播的可控性.最后,通过三个典型的支持细粒度委托的模型在映射机制下的具体实现,验证了RDBMPM模型的研究意义.展开更多
文摘At present, one of the important tasks of the ongoing college English teaching reform is to reform the traditional teaching mode,establishing the computer-based multimedia English teaching model. Based on the constructivist theory and the second language acquisi-tion theory, teachers who adopt the new teaching model should play multiple roles to maximize the teaching effect, being not only thecourse designer, organizer, but also the guide, helper and facilitator in the process of teaching students to construct knowledge and be en-gaged in classroom activities as well.
文摘针对现有RBAC(Role-Based Access Control)委托授权模型存在的不足:其一,没有有效地实现细致委托粒度;其二,权限传播没有得到很好的控制,给出一种基于映射机制的细粒度角色委托模型RDBMPM(Fine-Grained Role Delegation Model Based Permission Mapping Mechanism),该模型基于向量化与度量化算子的复合运算,提出了度量角色的概念,并以其为授权粒度对委托约束机制进行讨论,增强了权限传播的可控性.最后,通过三个典型的支持细粒度委托的模型在映射机制下的具体实现,验证了RDBMPM模型的研究意义.
