Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span...Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges.According to the approach,the seismic performance evaluation of the Sutong Bridge,which is a cable-stayed bridge with a main span of 1 088 m,is completed,and the practicality of the approach is validated.The earthquake resistance level for super-long span cable-stayed bridges is discussed,including the earthquake level,its corresponding structural performance and check indices.And a set of formula for capacity/demand ratio calculation of bridge components is proposed.展开更多
In this paper the authors show how software component design can affect security properties through different composition operators. The authors define software composition as the result of aggregating and/or associat...In this paper the authors show how software component design can affect security properties through different composition operators. The authors define software composition as the result of aggregating and/or associating a component to a software system. The component itself may be informational or functional and carry a certain level of security attribute. The authors first show that the security attributes or properties form a lattice structure when combined with the appropriate least upper bound and greatest lower bound type of operators. Three composition operators, named C l, C2 and C3 are developed. The system＇s security properties resulting from these compositions are then studied. The authors discuss how different composition operators maintain, relax and restrict the security properties. Finally, the authors show that C1 and C2 composition operators are order-sensitive and that C3 is order-insensitive.展开更多
基金National Key Technologies R&D Program(No.2006BAG04B01),research on technical standards,key structures and their characteristics of kilometer-magnitude cable-stayed bridges
文摘Based on the capacity/demand(C/D)analysis of bridge components,and life cycle and performance based seismic design principles,a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges.According to the approach,the seismic performance evaluation of the Sutong Bridge,which is a cable-stayed bridge with a main span of 1 088 m,is completed,and the practicality of the approach is validated.The earthquake resistance level for super-long span cable-stayed bridges is discussed,including the earthquake level,its corresponding structural performance and check indices.And a set of formula for capacity/demand ratio calculation of bridge components is proposed.
文摘In this paper the authors show how software component design can affect security properties through different composition operators. The authors define software composition as the result of aggregating and/or associating a component to a software system. The component itself may be informational or functional and carry a certain level of security attribute. The authors first show that the security attributes or properties form a lattice structure when combined with the appropriate least upper bound and greatest lower bound type of operators. Three composition operators, named C l, C2 and C3 are developed. The system＇s security properties resulting from these compositions are then studied. The authors discuss how different composition operators maintain, relax and restrict the security properties. Finally, the authors show that C1 and C2 composition operators are order-sensitive and that C3 is order-insensitive.
