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基于邻域K-shell分布的关键节点识别方法 被引量:3
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作者 吴亚丽 任远光 +3 位作者 董昂 周傲然 吴学金 郑帅龙 《计算机工程与应用》 CSCD 北大核心 2024年第2期87-95,共9页
复杂网络中关键节点的精准识别对于网络结构稳定和信息传播起着至关重要的作用。传统K-shell方法仅通过节点在网络中所处位置对节点的重要性进行评估,导致区分度不高。基于此,综合考虑了节点的全局信息和局部信息对节点重要性的影响,提... 复杂网络中关键节点的精准识别对于网络结构稳定和信息传播起着至关重要的作用。传统K-shell方法仅通过节点在网络中所处位置对节点的重要性进行评估,导致区分度不高。基于此,综合考虑了节点的全局信息和局部信息对节点重要性的影响,提出一种基于邻域K-shell分布的关键节点识别方法。该方法通过节点邻域Ks值定义节点的熵,从而反映邻居节点的K-shell分布特征。通过11个网络数据集上的仿真实验,验证了所提方法能够更准确地识别并区分复杂网络中的关键节点。 展开更多
关键词 复杂网络 关键节点 k-SHELL 易感-感染-恢复模型(SIR)
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基于K-means聚类和特征空间增强的噪声标签深度学习算法 被引量:1
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作者 吕佳 邱小龙 《智能系统学报》 CSCD 北大核心 2024年第2期267-277,共11页
深度学习中神经网络的性能依赖于高质量的样本,然而噪声标签会降低网络的分类准确率。为降低噪声标签对网络性能的影响,噪声标签学习算法被提出。该算法首先将训练样本集划分成干净样本集和噪声样本集,然后使用半监督学习算法对噪声样... 深度学习中神经网络的性能依赖于高质量的样本,然而噪声标签会降低网络的分类准确率。为降低噪声标签对网络性能的影响,噪声标签学习算法被提出。该算法首先将训练样本集划分成干净样本集和噪声样本集,然后使用半监督学习算法对噪声样本集赋予伪标签。然而,错误的伪标签以及训练样本数量不足的问题仍然限制着噪声标签学习算法性能的提升。为解决上述问题,提出基于K-means聚类和特征空间增强的噪声标签深度学习算法。首先,该算法利用K-means聚类算法对干净样本集进行标签聚类,并根据噪声样本集与聚类中心的距离大小筛选出难以分类的噪声样本,以提高训练样本的质量;其次,使用mixup算法扩充干净样本集和噪声样本集,以增加训练样本的数量;最后,采用特征空间增强算法抑制mixup算法新生成的噪声样本,从而提高网络的分类准确率。并在CIFAR10、CIFAR100、MNIST和ANIMAL-10共4个数据集上试验验证了该算法的有效性。 展开更多
关键词 噪声标签学习 深度学习 半监督学习 机器学习 神经网络 k-MEANS聚类 特征空间增强 mixup算法
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融合N-K模型的复杂网络船舶自沉事故风险因素耦合分析
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作者 崔秀芳 邵志鹏 +1 位作者 赖炜祺 曾杰熙 《安全与环境学报》 CAS CSCD 北大核心 2024年第9期3307-3314,共8页
为定量分析船舶自沉风险因素间的影响关系,识别导致船舶自沉事故的关键因素,科学预防事故的发生,引入融合N-K模型的复杂网络研究船舶自沉事故风险耦合。首先结合中国海事局公布的136起船舶自沉事故案例,分析事故致因,将船舶自沉事故风... 为定量分析船舶自沉风险因素间的影响关系,识别导致船舶自沉事故的关键因素,科学预防事故的发生,引入融合N-K模型的复杂网络研究船舶自沉事故风险耦合。首先结合中国海事局公布的136起船舶自沉事故案例,分析事故致因,将船舶自沉事故风险因素归纳为4个一级风险因素和15个二级风险因素,运用N-K模型计算出一级风险因素风险耦合的发生概率和风险值;然后,以二级风险因素为节点、致因关联为边,构建危险因子的关联网络,通过风险可达性分析和网络节点中心度分析,探究危险因子的作用机制,对危险因子进行初步识别,并以N-K模型计算的耦合值对节点中心度进行改进,获得最终的关键风险因素;最后,挖掘船舶自沉事故致因网络的凝聚子群并进行分析,得到密度矩阵,确定风险关联性最强的二级风险因素,以期从事故源头上采取有效措施,为船舶自沉事故的科学预防提供有益参考。结果表明:船舶自沉事故的发生与风险耦合值成正比,耦合因素越多则风险值越大;人的因素和船舶因素风险耦合易导致船舶自沉事故;导致船舶自沉事故的关键风险因素为安全意识淡薄、公司未履责、船舶管理不到位、公司管理不到位、船舶故障、船舶不适航,其中安全意识淡薄与其他风险关联性最大,须重点防范。 展开更多
关键词 安全工程 船舶自沉事故 N-k模型 复杂网络 耦合分析
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改进K-shell算法的城市道路网关键交叉口识别
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作者 裴玉龙 刘鹤行 王子奇 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第4期146-153,共8页
交叉口重要性不仅与自身属性相关,还受相邻路段属性的影响,针对城市道路网中关键交叉口识别方法准确率不足的问题,提出一种考虑城市道路网特性的改进K-shell算法。即在传统K-shell算法基础上,综合考虑交叉口及其相邻路段的结构特性与交... 交叉口重要性不仅与自身属性相关,还受相邻路段属性的影响,针对城市道路网中关键交叉口识别方法准确率不足的问题,提出一种考虑城市道路网特性的改进K-shell算法。即在传统K-shell算法基础上,综合考虑交叉口及其相邻路段的结构特性与交通特性,提出交叉口重要度的概念,利用CRITIC法确定交叉口重要度中相关指标的权重系数,对城市道路网中的交叉口进行重要性排序。以哈尔滨市二环内道路网为例,构建级联失效模型,分析随着失效交叉口比例的增加,不同排序方法下的网络效率、网络最大连通子图比率、故障节点比率的波动情况,结果表明,改进K-shell算法能够更加有效地识别城市道路网关键交叉口。 展开更多
关键词 城市道路网 关键交叉口 k-SHELL 交叉口重要度
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基于变分图自动编码器与K均值聚类的虚拟网络嵌入算法应用
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作者 姚丽敏 《哈尔滨师范大学自然科学学报》 CAS 2024年第1期47-54,共8页
将虚拟网络映射到物理网络是网络功能虚拟化中一项重要的任务.为了有效地分配虚拟网络请求,需要将虚拟网络嵌入到物理网络拓扑中.然而,由于虚拟网络的复杂性和物理网络的限制,这一任务变得非常具有挑战性.鉴于此,研究在现有虚拟网络嵌... 将虚拟网络映射到物理网络是网络功能虚拟化中一项重要的任务.为了有效地分配虚拟网络请求,需要将虚拟网络嵌入到物理网络拓扑中.然而,由于虚拟网络的复杂性和物理网络的限制,这一任务变得非常具有挑战性.鉴于此,研究在现有虚拟网络嵌入算法(Virtual Network Embedding, VNE)模型基础上进行改进,融入了变分图自动编码器(Variational Graph Auto-Encoders, VGAE),提出了一种新型虚拟网络嵌入算法模型.通过编码器对虚拟网络的嵌入特征进行提取,随后利用K-means聚类算法对所得到的嵌入特征进行分类,最终得到合适的嵌入分配方法.实验结果表明,该新模型相较于其他同类型的嵌入算法性能表现最佳,稳定性最好,其平均嵌入请求接受率为60%,长期平均CPU资源利用率最高达97%.综上所述,研究提出的新型虚拟网络嵌入算法在资源利用率和嵌入质量方面表现出色,能够有效应对复杂的网络环境和大规模的虚拟网络请求. 展开更多
关键词 虚拟网络 变分图自动编码器 k-MEANS 嵌入算法 特征分配
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Soft Computing of Biochemical Oxygen Demand Using an Improved T–S Fuzzy Neural Network 被引量:4
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作者 乔俊飞 李微 韩红桂 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1254-1259,共6页
It is difficult to measure the online values of biochemical oxygen demand(BOD) due to the characteristics of nonlinear dynamics, large lag and uncertainty in wastewater treatment process. In this paper, based on the k... It is difficult to measure the online values of biochemical oxygen demand(BOD) due to the characteristics of nonlinear dynamics, large lag and uncertainty in wastewater treatment process. In this paper, based on the knowledge representation ability and learning capability, an improved T–S fuzzy neural network(TSFNN) is introduced to predict BOD values by the soft computing method. In this improved TSFNN, a K-means clustering is used to initialize the structure of TSFNN, including the number of fuzzy rules and parameters of membership function. For training TSFNN, a gradient descent method with the momentum item is used to adjust antecedent parameters and consequent parameters. This improved TSFNN is applied to predict the BOD values in effluent of the wastewater treatment process. The simulation results show that the TSFNN with K-means clustering algorithm can measure the BOD values accurately. The algorithm presents better approximation performance than some other methods. 展开更多
关键词 BIOCHEMICAL oxygen DEMAND WASTEWATER treatment T–S fuzzy NEURAL network k-MEANS clustering
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基于改进K-means聚类算法的网络异常数据挖掘与分类方法
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作者 贺萌 《无线互联科技》 2024年第18期119-122,共4页
为了解决网络异常数据挖掘过程中漏报率、误报率较高的问题,文章提出一种基于改进K-means聚类算法的网络异常数据挖掘与分类方法。文章通过构建并行化频繁项集挖掘环境加速数据处理,利用局部离群点检测剔除异常值,同时引入K-means聚类... 为了解决网络异常数据挖掘过程中漏报率、误报率较高的问题,文章提出一种基于改进K-means聚类算法的网络异常数据挖掘与分类方法。文章通过构建并行化频繁项集挖掘环境加速数据处理,利用局部离群点检测剔除异常值,同时引入K-means聚类对数据的最大最小距离展开计算,融合隶属度函数与密度峰值优化算法,改进聚类初始中心选择及簇边界调整,从而提高异常识别准确性和分类效率。通过实验结果证明,该方法能够明显改善聚类效果与性能。 展开更多
关键词 k-MEANS聚类算法 网络异常 数据挖掘 数据分类 离群点检测
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k阶采样和图注意力网络的知识图谱表示模型
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作者 刘文杰 姚俊飞 陈亮 《计算机工程与应用》 CSCD 北大核心 2024年第2期113-120,共8页
知识图谱表示(KGE)旨在将知识图谱中的实体和关系映射到低维度向量空间而获得其向量表示。现有的KGE模型只考虑一阶近邻,这影响了知识图谱中推理和预测任务的准确性。为了解决这一问题,提出了一种基于k阶采样算法和图注意力网络的KGE模... 知识图谱表示(KGE)旨在将知识图谱中的实体和关系映射到低维度向量空间而获得其向量表示。现有的KGE模型只考虑一阶近邻,这影响了知识图谱中推理和预测任务的准确性。为了解决这一问题,提出了一种基于k阶采样算法和图注意力网络的KGE模型。k阶采样算法通过聚集剪枝子图中的k阶邻域来获取中心实体的邻居特征。引入图注意力网络来学习中心实体邻居的注意力值,通过邻居特征加权和得到新的实体向量表示。利用ConvKB作为解码器来分析三元组的全局表示特征。在WN18RR、FB15k-237、NELL-995、Kinship数据集上的评价实验表明,该模型在链接预测任务上的性能明显优于最新的模型。此外,还讨论了阶数k和采样系数b的改变对模型命中率的影响。 展开更多
关键词 知识图谱表示 k阶采样算法 图注意力网络 剪枝子图 链接预测
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基于K-means聚类和BP神经网络的电梯能耗实时监测方法
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作者 彭诚 《通化师范学院学报》 2024年第4期50-56,共7页
针对现有方法在对电梯能耗进行监测时,存在监测精度低、用时长、监测结果不理想的问题,该文提出一种基于K-means聚类算法和BP神经网络相结合的电梯能耗实时监测方法 .在经过清洗的能耗数据中提取影响建筑能耗实时监测的主要因素特征值,... 针对现有方法在对电梯能耗进行监测时,存在监测精度低、用时长、监测结果不理想的问题,该文提出一种基于K-means聚类算法和BP神经网络相结合的电梯能耗实时监测方法 .在经过清洗的能耗数据中提取影响建筑能耗实时监测的主要因素特征值,利用相似系数法进行相似度计算,获取相似系数.对相似电梯能耗数据进行小波分解获取高低频序列,分别采用LSSVM-GSA检测方法和均方加权处理方法对低频和高频部分进行处理,将两个结果进行重构,得到最终的实时监测结果 .仿真实验结果表明:所提方法能够获取高精度、低耗时、高稳定性的监测结果 . 展开更多
关键词 电梯能耗 k-MEANS聚类算法 BP神经网络 数据清洗
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基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法
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作者 赵晓峰 王平水 《传感技术学报》 CAS CSCD 北大核心 2024年第6期1056-1060,共5页
无线传感网络节点体积小,隐蔽性强,节点复制攻击检测的难度较大,为此提出一种基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法。通过信标节点的空间位置数据与相距跳数得出各节点之间的相似程度,结合高斯径向基核函数求解未... 无线传感网络节点体积小,隐蔽性强,节点复制攻击检测的难度较大,为此提出一种基于组合加权k近邻分类的无线传感网络节点复制攻击检测方法。通过信标节点的空间位置数据与相距跳数得出各节点之间的相似程度,结合高斯径向基核函数求解未知节点的横轴、纵轴的空间坐标,确定各网络节点的空间位置;根据网络节点的属性特征与投票机制建立节点复制攻击模型,凭借组合加权k近邻分类法划分节点类型,并将结果传送至簇头节点,由簇头节点做出最后的仲裁,识别出节点复制攻击行为。仿真结果表明,所提方法的节点复制攻击检测率最大值为99.5%,最小值为97.9%,对节点复制攻击检测的耗时为5.41 s,通信开销数据包数量最大值为209个,最小值为81个。 展开更多
关键词 无线传感网络 攻击检测 组合加权k近邻分类 复制节点 部署区域 信标节点
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t/k-fault diagnosis algorithm of n-dimensional hypercube network based on the MM*model 被引量:4
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作者 LIANG Jiarong ZHOU Ning YUN Long 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第1期216-222,共7页
Compared with accurate diagnosis, the system’s selfdiagnosing capability can be greatly increased through the t/kdiagnosis strategy at most k vertexes to be mistakenly identified as faulty under the comparison model,... Compared with accurate diagnosis, the system’s selfdiagnosing capability can be greatly increased through the t/kdiagnosis strategy at most k vertexes to be mistakenly identified as faulty under the comparison model, where k is typically a small number. Based on the Preparata, Metze, and Chien(PMC)model, the n-dimensional hypercube network is proved to be t/kdiagnosable. In this paper, based on the Maeng and Malek(MM)*model, a novel t/k-fault diagnosis(1≤k≤4) algorithm of ndimensional hypercube, called t/k-MM*-DIAG, is proposed to isolate all faulty processors within the set of nodes, among which the number of fault-free nodes identified wrongly as faulty is at most k. The time complexity in our algorithm is only O(2~n n~2). 展开更多
关键词 hypercube network t/k-diagnosis algorithm multiprocessor systems the Maeng and Malek(MM)* model Preparata Metze and Chien(PMC)
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New shape clustering method based on contour DFT descriptor and modified SOFM neural network 被引量:1
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作者 刘威杨 徐向民 +1 位作者 梅剑寒 王为凯 《Journal of Beijing Institute of Technology》 EI CAS 2014年第1期89-95,共7页
A contour shape descriptor based on discrete Fourier transform (DFT) and a K-means al- gorithm modified self-organizing feature map (SOFM) neural network are established for shape clus- tering. The given shape is ... A contour shape descriptor based on discrete Fourier transform (DFT) and a K-means al- gorithm modified self-organizing feature map (SOFM) neural network are established for shape clus- tering. The given shape is first sampled uniformly in the polar coordinate. Then the discrete series is transformed to frequency domain and constructed to a shape characteristics vector. Firstly, sample set is roughly clustered using SOFM neural network to reduce the scale of samples. K-means algo- rithm is then applied to improve the performance of SOFM neural network and process the accurate clustering. K-means algorithm also increases the controllability of the clustering. The K-means algo- rithm modified SOFM neural network is used to cluster the shape characteristics vectors which is previously constructed. With leaf shapes as an example, the simulation results show that this method is effective to cluster the contour shapes. 展开更多
关键词 contour shape descriptor discrete Fourier transform (DFT) serf-organizing featuremap (SOFM) neural network k-means algorithm
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Basic Tenets of Classification Algorithms K-Nearest-Neighbor, Support Vector Machine, Random Forest and Neural Network: A Review 被引量:4
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作者 Ernest Yeboah Boateng Joseph Otoo Daniel A. Abaye 《Journal of Data Analysis and Information Processing》 2020年第4期341-357,共17页
In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (... In this paper, sixty-eight research articles published between 2000 and 2017 as well as textbooks which employed four classification algorithms: K-Nearest-Neighbor (KNN), Support Vector Machines (SVM), Random Forest (RF) and Neural Network (NN) as the main statistical tools were reviewed. The aim was to examine and compare these nonparametric classification methods on the following attributes: robustness to training data, sensitivity to changes, data fitting, stability, ability to handle large data sizes, sensitivity to noise, time invested in parameter tuning, and accuracy. The performances, strengths and shortcomings of each of the algorithms were examined, and finally, a conclusion was arrived at on which one has higher performance. It was evident from the literature reviewed that RF is too sensitive to small changes in the training dataset and is occasionally unstable and tends to overfit in the model. KNN is easy to implement and understand but has a major drawback of becoming significantly slow as the size of the data in use grows, while the ideal value of K for the KNN classifier is difficult to set. SVM and RF are insensitive to noise or overtraining, which shows their ability in dealing with unbalanced data. Larger input datasets will lengthen classification times for NN and KNN more than for SVM and RF. Among these nonparametric classification methods, NN has the potential to become a more widely used classification algorithm, but because of their time-consuming parameter tuning procedure, high level of complexity in computational processing, the numerous types of NN architectures to choose from and the high number of algorithms used for training, most researchers recommend SVM and RF as easier and wieldy used methods which repeatedly achieve results with high accuracies and are often faster to implement. 展开更多
关键词 Classification Algorithms NON-PARAMETRIC k-Nearest-Neighbor Neural networks Random Forest Support Vector Machines
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基于随机森林算法和K-means算法的网络攻击识别方法
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作者 荣文晶 高锐 +2 位作者 赵弘洋 云雷 彭辉 《电子产品可靠性与环境试验》 2024年第1期8-12,共5页
5G网络与核电的深度融合能够提升核电厂生产安全管控水平,减少人为事故,促进核电行业安全和经济发展。但由于网络的接入,为核电安全生产带来了一定的安全风险,恶意攻击者会通过向核电5G网络发起攻击进而破坏核电生产。为了解决核电5G网... 5G网络与核电的深度融合能够提升核电厂生产安全管控水平,减少人为事故,促进核电行业安全和经济发展。但由于网络的接入,为核电安全生产带来了一定的安全风险,恶意攻击者会通过向核电5G网络发起攻击进而破坏核电生产。为了解决核电5G网络场景下面临的网络异常和恶意攻击的问题,提出了一种在核电5G网络场景下基于随机森林算法和K-means算法的实时网络异常检测和网络攻击识别方法,对于提高核电网络安全具有重要的意义。 展开更多
关键词 随机森林算法 k-MEANS算法 网络异常检测 网络攻击识别
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分布式网络中连续时间周期的全局top-K频繁流测量
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作者 毛晨宇 黄河 +1 位作者 孙玉娥 杜扬 《计算机科学》 CSCD 北大核心 2024年第4期28-38,共11页
在分布式网络中,测量top-K频繁流对资源分配、安全监控等应用至关重要。现有的top-K频繁流测量工作存在不适用于测量分布式网络流量或只考虑单时间周期等局限。为此,提出了分布式网络中连续时间周期的全局top-K频繁流测量方案,在分布节... 在分布式网络中,测量top-K频繁流对资源分配、安全监控等应用至关重要。现有的top-K频繁流测量工作存在不适用于测量分布式网络流量或只考虑单时间周期等局限。为此,提出了分布式网络中连续时间周期的全局top-K频繁流测量方案,在分布节点中布置了紧凑的概率数据结构来记录网络流信息,每个时间周期结束后分布节点向中心节点发送必要信息,中心节点汇聚得到从测量开始至当前时间周期的全局top-K频繁流。考虑到每条流可能出现在一个或多个测量节点,使用了不同的方法来减少传输开销。对于每条流只会出现在单一节点的情况,采用传输分段最小值的方法来获得阈值,实验结果表明这种方法减少了全量传输超过50%的传输开销。对于每条流会出现在多个节点的情况,提出了多阶段无误差处理方法和单阶段快速处理方法,分别应对不能容忍误差的场景和实际高速网络流量,相比每个时间周期都使用已有单周期方法,传输开销的实验表现降低了两个数量级。最后还提出了一种利用历史平均增值信息降低通信延迟的方法,实验结果表明该方法有效降低了限制信息的平均相对误差。 展开更多
关键词 流量测量 top-k频繁流 分布式网络 连续时间周期 SkETCH
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Neural Networks for Logic Circuits 被引量:2
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作者 Liu Yongcai (School of Computer Engineering and Science) 《Advances in Manufacturing》 SCIE CAS 1998年第2期60-63,共4页
Bushnell and the author proposed the neural networks for NOT, AND, OR, NAND, NOR, XOR and XNOR gates. Using these neural networks, the neural networks of any logic circuits can be constructd. From this, the consistent... Bushnell and the author proposed the neural networks for NOT, AND, OR, NAND, NOR, XOR and XNOR gates. Using these neural networks, the neural networks of any logic circuits can be constructd. From this, the consistent signals in the logic circuits will be transformed into the global minimal points of a quadratic pseudo Boolean function. Thus the neural network application in the field of circuit modeling and automatic test pattern generation can be widened. 展开更多
关键词 neural network Hopfield network quadratic pseudo Boolean function k tree
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WEAK SEQUENCE-COVERING MAPPING AND CS-NETWORK
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作者 高国士 《苏州大学学报(自然科学版)》 CAS 1993年第2期105-111,共7页
A mapping f: X→Y is called weak sequence-covering if whenever {ya} is a sequence in Y converging to y ∈ Y, there exist a subsequence {ynk} and xk∈f^-1(ynk)(k∈N) ,x∈f^-1 (y) such that xk→x. The main results are: ... A mapping f: X→Y is called weak sequence-covering if whenever {ya} is a sequence in Y converging to y ∈ Y, there exist a subsequence {ynk} and xk∈f^-1(ynk)(k∈N) ,x∈f^-1 (y) such that xk→x. The main results are: (1) Y is a sequential, Frechet, strongly Frechet space iff every weak sepuence-covering mapping onto Y is quotient, pseudo-open, countably bi-quotient respectively, (2) weak sequence-covering mapping preserves cs-network and certain k-(cs-)networks, thus some new mapping theorems on k-(cs-)notworks are proved. 展开更多
关键词 CS-网络 软次序收敛 FRECHET空间 映射定理 k-网络
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Probabilistic analysis on fault tolerance of 3-Dimensional mesh networks
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作者 王高才 陈建二 +1 位作者 王国军 陈松乔 《Journal of Central South University of Technology》 2003年第3期255-259,共5页
The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes... The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes,and then the probability with which each submesh satisfies the defined condition is computed. If each submesh satis-fies the condition, then the whole mesh is connected. Consequently, the probability that a 3-D mesh is connected iscomputed assuming each node has a failure probability. Mathematical methods are used to derive a relationship be-tween network node failure probability and network connectivity probability. The calculated results show that the 3-D mesh networks can remain connected with very high probability in practice. It is formally proved that when thenetwork node failure probability is boutded by 0.45 %, the 3-D mesh networks of more than three hundred thousandnodes remain connected with probability larger than 99 %. The theoretical results show that the method is a power-ful technique to calculate the lower bound of the connectivity probability of mesh networks. 展开更多
关键词 3-D MESH networkS k-submesh CONNECTIVITY PROBABILITY analysis
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License Plate Recognition Based on Transform Coding and Neural Network
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作者 李小平 胡海生 +2 位作者 宋瀚涛 朱建学 丁俨 《Journal of Beijing Institute of Technology》 EI CAS 2003年第1期42-45,共4页
A method of vehicle license plate recognition utilizing Karhunen-Loeve(K-L) transform is provided. The transform is used to extract features from a mass of image templates, to describe high-dimensional images with low... A method of vehicle license plate recognition utilizing Karhunen-Loeve(K-L) transform is provided. The transform is used to extract features from a mass of image templates, to describe high-dimensional images with low-dimensional ones, and moreover, to implement data compression and play down complexity of the neural network. With the character to reduce eigenspace dimensionality of K-L transform and the ability to map data of BP network, the method does effectively in recognizing license plates. 展开更多
关键词 k-L transform BP network pattern recognition
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A Fast Heuristic Algorithm for Minimizing Congestion in the MPLS Networks
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作者 Chengwen Jiao Suixiang Gao +2 位作者 Wenguo Yang Yinben Xia Mingming Zhu 《International Journal of Communications, Network and System Sciences》 2014年第8期294-302,共9页
In the multiple protocol label-switched (MPLS) networks, the commodities are transmitted by the label-switched paths (LSPs). For the sake of reducing the total cost and strengthening the central management, the MPLS n... In the multiple protocol label-switched (MPLS) networks, the commodities are transmitted by the label-switched paths (LSPs). For the sake of reducing the total cost and strengthening the central management, the MPLS networks restrict the number of paths that a commodity can use, for maintaining the quality of service (QoS) of the users, the demand of each commodity must be satisfied. Under the above conditions, some links in the network may be too much loaded, affecting the performance of the whole network drastically. For this problem, in [1], we proposed two mathematical models to describe it and a heuristic algorithm which quickly finds transmitting paths for each commodity are also presented. In this paper, we propose a new heuristic algorithm which finds a feasible path set for each commodity, and then select some paths from the path set through a mixed integer linear programming to transmit the demand of each commodity. This strategy reduces the scale of the original problem to a large extent. We test 50 instances and the results show the effectiveness of the new heuristic algorithm. 展开更多
关键词 MPLS-network k-Splittable Flow Minimum CONGESTION HEURISTIC Algorithm
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