An improvement of tolerance relation is proposed in regard to rough set model based on connection degree by which reflexivity of relation can be assured without loss of information. Then, a method to determine optimal...An improvement of tolerance relation is proposed in regard to rough set model based on connection degree by which reflexivity of relation can be assured without loss of information. Then, a method to determine optimal identity degree based on relative positive region is proposed so that the identity degree can be computed in an objective method without any preliminary or additional information about data, which is consistent with the notion of objectivity in rough set theory and data mining theory. Subsequently, an algorithm is proposed, and in two examples, the global optimum identity degree is found out. Finally, in regard to optimum connection degree, the method of rules extraction for connection degree rough set model based on generalization function is presented by which the rules extracted from a decision table are enumerated.展开更多
针对容迟网络中节点存储空间有限从而出现大量丢包情况的问题,本文提出了一种适用于节点环境状态的拥塞控制管理策略(congestion control management strategy suitable for the state of the node environment,NEMS):该策略由节点间位...针对容迟网络中节点存储空间有限从而出现大量丢包情况的问题,本文提出了一种适用于节点环境状态的拥塞控制管理策略(congestion control management strategy suitable for the state of the node environment,NEMS):该策略由节点间位置差异相关的控制保留策略和节点自差异相关的丢包策略构成.首先根据节点剩余缓存空间的大小判断节点是处于忙碌状态(BS)还是崩溃状态(CS),当节点处于BS状态时,节点间位置差异相关的控制保留策略结合门限度和连接活跃值的概念分析是否留存新消息.节点自差异相关的丢包策略利用熵权法动态计算各个节点中不同消息属性权重,得到消息丢弃优先级.当拥塞发生,优先删除丢弃优先级大的消息.同时,引入ACK反馈机制,消除网络中已成功投递的冗余消息.仿真结果表明,与无缓存管理的路由策略相比,加入NEMS后使得消息成功投递率增加了约100.93%~200.67%,网络负载降低了约76.05%~81.42%.展开更多
基金supported by the National Natural Science Foundation of China (70571032)
文摘An improvement of tolerance relation is proposed in regard to rough set model based on connection degree by which reflexivity of relation can be assured without loss of information. Then, a method to determine optimal identity degree based on relative positive region is proposed so that the identity degree can be computed in an objective method without any preliminary or additional information about data, which is consistent with the notion of objectivity in rough set theory and data mining theory. Subsequently, an algorithm is proposed, and in two examples, the global optimum identity degree is found out. Finally, in regard to optimum connection degree, the method of rules extraction for connection degree rough set model based on generalization function is presented by which the rules extracted from a decision table are enumerated.
文摘针对容迟网络中节点存储空间有限从而出现大量丢包情况的问题,本文提出了一种适用于节点环境状态的拥塞控制管理策略(congestion control management strategy suitable for the state of the node environment,NEMS):该策略由节点间位置差异相关的控制保留策略和节点自差异相关的丢包策略构成.首先根据节点剩余缓存空间的大小判断节点是处于忙碌状态(BS)还是崩溃状态(CS),当节点处于BS状态时,节点间位置差异相关的控制保留策略结合门限度和连接活跃值的概念分析是否留存新消息.节点自差异相关的丢包策略利用熵权法动态计算各个节点中不同消息属性权重,得到消息丢弃优先级.当拥塞发生,优先删除丢弃优先级大的消息.同时,引入ACK反馈机制,消除网络中已成功投递的冗余消息.仿真结果表明,与无缓存管理的路由策略相比,加入NEMS后使得消息成功投递率增加了约100.93%~200.67%,网络负载降低了约76.05%~81.42%.
