A new family of Cayley graph interconnection networks of constantdegree four

We propose a new family of interconnection networks that are Cayley graphs with constant node degree 4. These graphs are regular, have logarithmic diameter, and are maximally fault tolerant. We investigate different algebraic properties of these networks (including fault tolerance) and propose optimal routing algorithms. As far as we know, this is the first family of Cayley graphs of constant degree 4     

Comments on “A new family of Cayley graph interconnectionnetworks of constant degree four”

For original paper see Vadapalli and Srimani, ibid., vol. 7, no. 1, p 26-32, 1996, where the authors have proposed a new family of Cayley graph interconnection networks of constant degree four. Our comments show that their proposed graph is not new but is the same as the wrap-around butterfly graph. The structural kinship of the proposed graph with the de Bruijn graph is also discussed     

Time complexity of a path formulated optimal routing algorithm

A detailed analysis of convergence rate is presented for an iterative path formulated optimal routing algorithm. In particular, it is quantified, analytically, how the convergence rate changes as the number of nodes in the underlying graph increases. The analysis is motivated by a particular path formulated gradient projection algorithm that has demonstrated excellent convergence rate properties through extensive numerical studies. The analytical result proven in this note is that the number of iterations for convergence depends on the number of nodes only through the network diameter     

双环Petersen网络直径公式及最优路由算法

双环Petersen图互联网络DLCPG(k)是双环网络与Petersen图的笛卡尔积,它具有良好的可扩展性、较短的网络直径和简单的拓扑结构等特性。通过研究其拓扑结构,得到了DLCPG(k)直径的显式公式,并给出了该网络的最优单播路由算法。     

A new optimal algorithm for the permutation flow-shop problem and its parallel implementation

This paper describes a new parallel algorithm for solving n-job, m-machine flow-shop problems. The algorithm is basically a parallelization of the usual branch-and-bound method. It also takes advantage of all search method to keep high efficiency of parallel processing, when the sub-problem becomes smaller than certain size. It is shown that its implementation on both nCUBE2 and LUNA88k2 gives very good performance characteristics.     

A new HAD algorithm for optimal routing of hierarchicallystructured data networks

In this paper, a new algorithm based on hierarchical aggregation/disaggregation and decomposition/composition (HAD) scheme is proposed to solve the optimal routing problems (ORP) for hierarchically structured networks of multi-layer backbones. Our algorithm has two major differences with the existing HAD algorithms for hierarchically clustered networks: (1) our algorithm works with more general networks than the networks with the clustered structure; (2) our algorithm parallelizes the computations for different commodities (message flows defined by a pair of origin node and destination node) so that it speeds up with a parallel time complexity of O(mlog²(n)), which is much less than O(Mlog²(n)) needed for the existing HAD algorithms. Here, n is the number of nodes in the network; M is the number of commodities and m is a positive number usually much smaller than M and is a function of the patterns of all the commodities including the locations of all origin nodes and destination nodes, and the flow demand of each commodity. Furthermore, our algorithm can make a trade-off between the run time and the optimality, i.e., by allowing the solution to be sub-optimal, our algorithm can save great amount of computation time. The implementation of the algorithm for a 200-node network is simulated using OPNET simulation package (OPNET or Optimized Network Engineering Tools is developed by MIL3, Inc.), and the test results are consistent with our analysis     

基于最优簇数和改进引力搜索的WSN路由算法

为了提高无线传感器网络（WSN）的能量利用效率,提出一种基于最优簇数和改进引力搜索的WSN路由算法（ONCIGS）。首先,根据非均匀分簇的思想计算最优簇数,并采用改进的凝聚嵌套（AGNES）算法实现网络的合理分簇;其次,将反向学习机制和精英策略思想引入到引力搜索算法中,并基于种群密度对作用力进行自适应调整,以提高搜索精度,加快收敛;然后,将簇头剩余能量的标准差作为目标函数,搜索能量均衡的簇间数据转发路径。实验结果表明,相比低功耗自适应集簇分层型（LEACH）路由算法和分布式能量均衡非均匀成簇（DEBUC）路由算法,ONCIGS在100 m×100 m网络规模下将网络生命周期分别延长41.94%和5.77%,在200 m×200 m网络规模下分别延长76.60%和7.82%。ONCIGS能够有效地延长网络寿命,提高能量效率。     

一类有向双环网络的最优单播路由算法

有向双环网络G(N;1,h)(N是节点数,1和h是步长)是重要的互联网络结构。给出了有向双环网络G(N;1,h)的若干性质。作为这些性质的两个应用,给出一类有向双环网络的直径公式,以及这类有向双环网络的单播路由算法,这个算法是简单且最优的。     

基于通信链路质量的无线HART图路由算法实现

图路由是无线HART提出的路由机制,目前对图路由算法的研究较少.提出了一种基于通信链路质量的无线HART图路由算法,引入路径稳定度作为判断链路质量的机制.采用基于路径稳定度的分层算法,保证跳数最少和通信可靠性;依据层间节点的路径稳定度选择层间路由,保证层间路由冗余性和可靠性,实现了无线HART的图路由算法,并应用到无线HART网络管理者中.     

不同合作度下机会网络典型路由算法健壮性分析*

机会网络路由算法在不同合作度下的健壮性是一个重要的但未被充分研究的问题,分析了机会网络中可能存在的节点间不合作的情况,定义了三种适用于不同场景的节点合作度,设计了评价方法及指标体系,通过对真实城市场景中带有智能蓝牙设备行人移动行为的仿真,定量分析了不同节点合作度下Direct Delivery、Epidemic、Spray and Wait、Prophet和MaxProp 五种典型路由算法的健壮性。结果表明Spray and Wait和MaxProp算法健壮性较差,Prophet 和Epidemic算法较     

Branch pipe routing based on 3D connection graph and concurrent ant colony optimization algorithm

Pipe routing, in particular branch pipes with multiple terminals, has an important influence on product performance and reliability. This paper develops a new rectilinear branch pipe routing approach for automatic generation of the optimal rectilinear branch pipe routes in constrained spaces. Firstly, this paper presents a new 3D connection graph, which is constructed by extending a new 2D connection graph. The new 2D connection graph is constructed according to five criteria in discrete Manhattan spaces. The 3D connection graph can model the 3D constrained layout space efficiently. The length of pipelines and the number of bends are modeled as the optimal design goal considering the number of branch points and three types of engineering constraints. Three types of engineering constraints are modeled by this 3D graph and potential value. Secondly, a new concurrent Max–Min Ant System optimization algorithm, which adopts concurrent search strategy and dynamic update mechanism, is used to solve Rectilinear Branch Pipe Routing optimization problem. This algorithm can improve the search efficiency in 3D constrained layout space. Numerical comparisons with other current approaches in literatures demonstrate the efficiency and effectiveness of the proposed approach. Finally, a case study of pipe routing for aero-engines is conducted to validate this approach.     

Time complexity of a path formulated optimal routing algorithm(second printing)

A detailed analysis of convergence rate is presented for an iterative path formulated optimal routing algorithm. In particular, it is quantified, analytically, how the convergence rate changes as the number of nodes in the underlying graph increases. The analysis is motivated by a particular path formulated gradient projection algorithm that has demonstrated excellent convergence rate properties through extensive numerical studies. The analytical result proven in this note is that the number of iterations for convergence depends on the number of nodes only through the network diameter     

基于均衡接近度灰关联的增强二部图推荐算法

协同过滤推荐算法的数据稀疏性与冷启动问题影响和制约了推荐的质量,传统用户—项目二部图信任和相似度计算受局部个别点关联因素的消极影响。首先提出一种基于均衡接近度灰关联方法计算项目流行度的二部图信任推荐,在此基础上提出用户偏好的增强二部图直接信任度机制,然后通过JMSD相关系数作为全局信任推荐。在MovieLens数据集下的对比实验表明,与基准算法对比改进的算法模型具有更低的平均绝对误差（MAE）,提高了推荐质量,改善了冷启动问题。     

3D hexagonal network: modeling, topological properties, addressing scheme, and optimal routing algorithm

The 2D hexagonal mesh, based on triangle plane tessellation, is considered as a multiprocessor interconnection network. The 3D hexagonal mesh is presented as a natural extension of the hexagonal mesh. Although the topological properties of the 2D hexagonal mesh are well known, existing addressing schemes are not suitable to be extended to 3D hexagonal mesh. Then, we present, in this paper, a new addressing scheme and an optimal routing algorithm for 2D hexagonal network based on the distance formula and using shortest paths. We propose also a 3D hexagonal network that can be built with 2D hexagonal meshes as a natural generalization. We also present some topological properties, an efficient addressing scheme, and an optimal routing algorithm based on our 2D routing algorithm.     

Efficient associative algorithm to find the least spanning tree of a graph with a node degree constraint

Conclusion  We have described an associative algorithm to find the smallest spanning tree of a graph with a degree constraint on one of the nodes. The associative algorithm is based on Gabow's algorithm. It is described as a STAR procedure that runs in timeO(@#@ nlogn). This is also the time it takes to construct a minimum spanning tree of a graph on an associative parallel processor [4]. The associative algorithm relies on a number of new constructions that are also useful for other problems. Note that, unlike [13], we use a very simple and natural data representation on an associative parallel processor in the form of two-dimensional binary-coded tables. Translated from Kibernetika i Sistemnyi Analiz, No. 1., pp. 94–103, January–February, 1998.     

Chord路由算法的研究与改进

高效查找资源是P2P网络的关键。Chord是一种结构化的P2P网络,存在路由表信息冗余、查找效率不高的问题。为此,提出了一种改进的Chord路由算法,在不增加路由表长度的前提下,将路由表中的重复表项删除,同时增加相同数目的反向路由。仿真实验表明,算法消除了路由表信息冗余,减少了平均查找跳数,提高了查找效率,使提高查找效率和控制路由表长度得到很好的统一。     

Robust routing and optimal partitioning of a traffic demand polytope

In this paper we consider the problem of optimal partitioning of a traffic demand polytope using a hyperplane. In our model all possible demand matrices belong to a polytope. The polytope can be divided into parts, and different routing schemes can be applied while dealing with traffic matrices from different parts of the polytope. We consider three basic models: Robust‐Routing, No‐Sharing and Dynamic‐Routing. We apply two different partitioning strategies depending on whether the reservation vectors on opposite sides of the hyperplane are required to be identical, or allowed to differ. We provide efficient algorithms that solve these problems. Moreover, we prove polynomiality of some of the considered cases. Finally, we present numerical results proving the applicability of the introduced algorithms and showing differences between the routing strategies.     

基于遗传算法和蚁群算法融合的QoS路由算法*

面向QoS路由问题,设计了一种基于遗传算法和蚁群算法融合的QoS路由算法(QoS routing algorithm according to the combination of the genetic algorithm and ant colony algorithm,GAACO_QoS).利用遗传算法生成初始解,将其转换为蚁群算法所需的信息素初值,然后利用蚁群算法求取最优解.设置遗传算法控制函数来控制遗传算法和蚁群算法融合的适当时机.通过与遗传算法以及蚁群算法的比较,进一步说明算法的有效性.     

JXTA路由改进算法的研究与实现

P2P是当前网络研究的热点问题,JXTA是一个可提供各种P2P服务和应用的通用平台。本文着重介绍了JXTA路由算法,分析了JXTA路由存在的问题,在此基础上并结合性能分析,提出了基于族类算法和DHT的改进JXTA路由算法并给出了实现。