研究发现,Linux的内核模块具有良好的可控性而Linux的软中断具有极强的实时性。提出把两者有机地结合起来作为逻辑功能块(Logical Functional B lock,LFB)的实现机制,并用流标识号(PkfID)来描述LFB。实验表明采用这种方法实现的LFB能很...研究发现,Linux的内核模块具有良好的可控性而Linux的软中断具有极强的实时性。提出把两者有机地结合起来作为逻辑功能块(Logical Functional B lock,LFB)的实现机制,并用流标识号(PkfID)来描述LFB。实验表明采用这种方法实现的LFB能很好地满足ForCES需求(RFC 3654)。展开更多
当今IP路由器的一个发展趋势是控制器(Con tro l E lem en t,CE)与转发器(Forw ard ing E lem en t,FE)的分离(Forw ard ing and Con tro l E lem en t Separation)。基于控制器和转发器分离的IP路由器比传统模式的IP路由器具有更高的...当今IP路由器的一个发展趋势是控制器(Con tro l E lem en t,CE)与转发器(Forw ard ing E lem en t,FE)的分离(Forw ard ing and Con tro l E lem en t Separation)。基于控制器和转发器分离的IP路由器比传统模式的IP路由器具有更高的可配置性和灵活性,更容易满足新业务对网络提出的新要求,从根本上解决IP路由器的Q oS问题。控制器在IP路由器中至关重要,他通过向转发器发送控制消息来控制整个路由器的动作,并且及时反映转发器的属性信息。对基于ForCES(Forw ard ing and Con tro l E lem en t Separation)结构的IP路由器中控制器进行了研究与实现,重点介绍网络件(N etw orkE lem en t,NE)信息描述的实现原理和逻辑功能块(Log ica l Function B lock,LFB)拓扑结构图形化显示的实现原理,最后给出了测试结果。展开更多
为了改进目前IP路由器的可扩展性和灵活性等特点,研究基于开放可编程的新一代路由器架构。介绍了控制和转发相分离的ForCES协议框架和In te l IXA结构,提出了一种基于网络处理器IXP 2400并支持ForCES协议的开放可编程的路由器框架。详...为了改进目前IP路由器的可扩展性和灵活性等特点,研究基于开放可编程的新一代路由器架构。介绍了控制和转发相分离的ForCES协议框架和In te l IXA结构,提出了一种基于网络处理器IXP 2400并支持ForCES协议的开放可编程的路由器框架。详细地分析了转发件中X sca le层的设计和实现。在此基础上设计了相应的测试平台,实验结果表明了这种路由器框架的可行性。展开更多
The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The s...The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.展开更多
A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station,especially for efficiency and safety.A multi-force vector grid model was presented to simulate t...A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station,especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians.The model improves rule-based characteristics of cellular automata,details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements.Two general scenarios in corridor were simulated.One is bidirectional pedestrian flow simulation with isolation facility,and the other is bidirectional pedestrian flow simulation without isolation facility,where there exists disturbance in the middle.Through simulation,some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.展开更多
Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserv...Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserve caused by human activities have become one of the most serious environmental problems.The conflict between local展开更多
文摘研究发现,Linux的内核模块具有良好的可控性而Linux的软中断具有极强的实时性。提出把两者有机地结合起来作为逻辑功能块(Logical Functional B lock,LFB)的实现机制,并用流标识号(PkfID)来描述LFB。实验表明采用这种方法实现的LFB能很好地满足ForCES需求(RFC 3654)。
文摘当今IP路由器的一个发展趋势是控制器(Con tro l E lem en t,CE)与转发器(Forw ard ing E lem en t,FE)的分离(Forw ard ing and Con tro l E lem en t Separation)。基于控制器和转发器分离的IP路由器比传统模式的IP路由器具有更高的可配置性和灵活性,更容易满足新业务对网络提出的新要求,从根本上解决IP路由器的Q oS问题。控制器在IP路由器中至关重要,他通过向转发器发送控制消息来控制整个路由器的动作,并且及时反映转发器的属性信息。对基于ForCES(Forw ard ing and Con tro l E lem en t Separation)结构的IP路由器中控制器进行了研究与实现,重点介绍网络件(N etw orkE lem en t,NE)信息描述的实现原理和逻辑功能块(Log ica l Function B lock,LFB)拓扑结构图形化显示的实现原理,最后给出了测试结果。
文摘为了改进目前IP路由器的可扩展性和灵活性等特点,研究基于开放可编程的新一代路由器架构。介绍了控制和转发相分离的ForCES协议框架和In te l IXA结构,提出了一种基于网络处理器IXP 2400并支持ForCES协议的开放可编程的路由器框架。详细地分析了转发件中X sca le层的设计和实现。在此基础上设计了相应的测试平台,实验结果表明了这种路由器框架的可行性。
文摘The near crack line analysis method was used to investigate a crack loaded by two pairs of point shear forces in an infinite plate in an elastic-perfectly plastic solid, and the analytical solution was obtained. The solutions include: the unit normal vector of the elastic-plastic boundary near the crack line, the elastic-plastic stress fields near crack line, law that the length of the plastic zone along the crack line is varied with an external loads, and the bearing capacity of an infinite plate with a center crack loaded by two pairs of point shear forces. The results are sufficiently precise near the crack line because the assumptions of the small scale yielding theory have not been made and no other assumption have been taken.
基金Project(51238008)supported by the National Natural Science Foundation of ChinaProject(CXZZ13_0116)supported by the Fundamental Research Funds for the Central Universities of ChinaProject(YBJJ1344)supported by the Scientific Research Foundations of Graduate School of Southeast University,China
文摘A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station,especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians.The model improves rule-based characteristics of cellular automata,details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements.Two general scenarios in corridor were simulated.One is bidirectional pedestrian flow simulation with isolation facility,and the other is bidirectional pedestrian flow simulation without isolation facility,where there exists disturbance in the middle.Through simulation,some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.
文摘Natural reserve can provide ecology system with natural background for human being and has important significance for sustaining ecosystem service.The continuous damage and deterioration of ecosystem in natural reserve caused by human activities have become one of the most serious environmental problems.The conflict between local