网络应用的发展,要求路由器必须有能力支持防火墙、入侵检测、提供 QoS、流量计费等一系列功能,这些功能都要求路由器对IP包进行分类来完成对数据包的不同处理。目前的包分类算法不适用于大规模的规则数据库。该文在现有的一种基于位...网络应用的发展,要求路由器必须有能力支持防火墙、入侵检测、提供 QoS、流量计费等一系列功能,这些功能都要求路由器对IP包进行分类来完成对数据包的不同处理。目前的包分类算法不适用于大规模的规则数据库。该文在现有的一种基于位串的包分类算法上做了两个改进,位串的聚合和过滤规则的重排列。从而生成了一种新的包分类机制-ABV(Aggregated Bit Vector)。通过评测可看出这种新的算法可以很好地应用在大规模规则数据库上,性能比原先有很大提升。展开更多
针对传统分类算法在处理非平衡数据集所出现的少数类分类准确率较低的问题,通过引入加权系数和样本分布函数给出了一种新的模糊规则权重的计算方法.该方法加强了类间的对比度和差异性,削弱了类内差距.将该权重方法与Chi et al规则生成...针对传统分类算法在处理非平衡数据集所出现的少数类分类准确率较低的问题,通过引入加权系数和样本分布函数给出了一种新的模糊规则权重的计算方法.该方法加强了类间的对比度和差异性,削弱了类内差距.将该权重方法与Chi et al规则生成算法和模糊分类推理模型结合形成新的分类算法,对具有不同非平衡度的UCI数据集进行Matlab对比研究,所得结果验证了该算法的可靠性与有效性.展开更多
An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ sch...An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ scheme is well formulated and efficiently solved by a linear-programming method, along with a one-dimensional approach for density evolution. Compared to IR-HARQ schemes based on turbo codes, simulation shows that the proposed IR-HARQ schemes based on IRA codes may achieve almost the same performance at a block size of 1 024, but better throughput at a block size of 4 096. The advantages of the proposed scheme in implementation, including decoding complexity and parallelism, make it more attractive in practice than the IR-HARQ schemes based on both turbo and LDPC codes.展开更多
文摘网络应用的发展,要求路由器必须有能力支持防火墙、入侵检测、提供 QoS、流量计费等一系列功能,这些功能都要求路由器对IP包进行分类来完成对数据包的不同处理。目前的包分类算法不适用于大规模的规则数据库。该文在现有的一种基于位串的包分类算法上做了两个改进,位串的聚合和过滤规则的重排列。从而生成了一种新的包分类机制-ABV(Aggregated Bit Vector)。通过评测可看出这种新的算法可以很好地应用在大规模规则数据库上,性能比原先有很大提升。
文摘针对传统分类算法在处理非平衡数据集所出现的少数类分类准确率较低的问题,通过引入加权系数和样本分布函数给出了一种新的模糊规则权重的计算方法.该方法加强了类间的对比度和差异性,削弱了类内差距.将该权重方法与Chi et al规则生成算法和模糊分类推理模型结合形成新的分类算法,对具有不同非平衡度的UCI数据集进行Matlab对比研究,所得结果验证了该算法的可靠性与有效性.
基金The National High Technology Research and Develop-ment Program of China(863Program)(No.2006AA01Z263)the National Natural Science Foundation of China(No.60672081)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK2006502)the Open Research Fund of National Mobile Communications Research Laboratory of Southeast Uni-versity(No.2008N01)
文摘An incremental redundancy hybrid automatic repeat- request (IR-HARQ)scheme based on irregular repeat-accumulate (IRA)codes is proposed. The design of rate compatible punctured IRA codes suitable for an IR-HARQ scheme is well formulated and efficiently solved by a linear-programming method, along with a one-dimensional approach for density evolution. Compared to IR-HARQ schemes based on turbo codes, simulation shows that the proposed IR-HARQ schemes based on IRA codes may achieve almost the same performance at a block size of 1 024, but better throughput at a block size of 4 096. The advantages of the proposed scheme in implementation, including decoding complexity and parallelism, make it more attractive in practice than the IR-HARQ schemes based on both turbo and LDPC codes.