By the generalized variational principle of two kinds of variables in general me-chanics,it was demonstrated that two Lagrangian classical relationships can be applied to both holonomic systems and nonholonomic system...By the generalized variational principle of two kinds of variables in general me-chanics,it was demonstrated that two Lagrangian classical relationships can be applied to both holonomic systems and nonholonomic systems. And the restriction that two Lagrangian classical relationships cannot be applied to nonholonomic systems for a long time was overcome. Then,one important formula of similar La-grangian classical relationship called the popularized Lagrangian classical rela-tionship was derived. From Vakonomic model,by two Lagrangian classical rela-tionships and the popularized Lagrangian classical relationship,the result is the same with Chetaev's model,and thus Chetaev's model and Vakonomic model were unified. Simultaneously,the Lagrangian theoretical framework of dynamics of nonholonomic system was established. By some representative examples,it was validated that the Lagrangian theoretical framework of dynamics of nonholonomic systems is right.展开更多
本文论述了图书馆期刊发布系统的计算机软件结构,介绍了在Microsof.tNET Framework2.0技术下图书馆期刊发布系统的优点与缺点,并结合本馆自身实例介绍了如何利用Microsoft公司最新的开发工具Visual Studio 2005来实现图书馆期刊发布系...本文论述了图书馆期刊发布系统的计算机软件结构,介绍了在Microsof.tNET Framework2.0技术下图书馆期刊发布系统的优点与缺点,并结合本馆自身实例介绍了如何利用Microsoft公司最新的开发工具Visual Studio 2005来实现图书馆期刊发布系统的计算机软件。展开更多
Microsoft．NET Framework中的安全性包含许多技术；基类库（BCL，Base Class Library）和ASP．NET中基于角色的安全、BCL中的密码系统类以及新的对使用访问控制列表（ACL，Access Control List）的支持即为其中的少数几个例子。公共语...Microsoft．NET Framework中的安全性包含许多技术；基类库（BCL，Base Class Library）和ASP．NET中基于角色的安全、BCL中的密码系统类以及新的对使用访问控制列表（ACL，Access Control List）的支持即为其中的少数几个例子。公共语言运行库（CLR，Common Language Runtime）提供的．NET安全性系列中的技术之一就是代码访问安全性（CAS，Code Access Security）。本文讨论．NET安全性中CAS的角色以及．NET Framework2．0的CAS中的一些关键的新功能和更改。展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 10272034)the Research Fund for the Doctoral Program of Higher Education of Chinathe Basic Research Foundation of Harbin Engineering University (Grant No. 20060217020)
文摘By the generalized variational principle of two kinds of variables in general me-chanics,it was demonstrated that two Lagrangian classical relationships can be applied to both holonomic systems and nonholonomic systems. And the restriction that two Lagrangian classical relationships cannot be applied to nonholonomic systems for a long time was overcome. Then,one important formula of similar La-grangian classical relationship called the popularized Lagrangian classical rela-tionship was derived. From Vakonomic model,by two Lagrangian classical rela-tionships and the popularized Lagrangian classical relationship,the result is the same with Chetaev's model,and thus Chetaev's model and Vakonomic model were unified. Simultaneously,the Lagrangian theoretical framework of dynamics of nonholonomic system was established. By some representative examples,it was validated that the Lagrangian theoretical framework of dynamics of nonholonomic systems is right.
文摘Microsoft．NET Framework中的安全性包含许多技术；基类库（BCL，Base Class Library）和ASP．NET中基于角色的安全、BCL中的密码系统类以及新的对使用访问控制列表（ACL，Access Control List）的支持即为其中的少数几个例子。公共语言运行库（CLR，Common Language Runtime）提供的．NET安全性系列中的技术之一就是代码访问安全性（CAS，Code Access Security）。本文讨论．NET安全性中CAS的角色以及．NET Framework2．0的CAS中的一些关键的新功能和更改。
