基于能量变化的无线传感器网络覆盖算法

设计了一种基于能量变化的无线传感器网络覆盖算法.通常网络节点连接的通信范围应该大于两倍的感应范围,但这将导致网络能耗的增加.提出的算法采用最少数量的节点来解决传感器网络的覆盖率和网络的连通性问题.测量结果表明,提出的覆盖算法可以满足传感器节点的通信范围小于两倍的感应范围.这将降低传感器网络的能量损耗.算法通过使用不同能量水平的活跃节点来降低能量损耗,并且可以延长系统的使用寿命.     

极大非独立集可削去的因子临界图

如果对一个简单图G的每一个与G的顶点数同奇偶的独立集I，都有G-I有完美匹配，则称G是独立集可削去的因子临界图．如果图G不是独立集可削去的因子临界图，而对任意两个小相邻的顶点x与y，G xy足独立集可削去的因子临界图，则称G足极大非独立集可削去的因子临界图，本刻画了极大非独立集可削去的因子临界图。     

基于无线传感器网络的可靠性模型及上界

无线传感器网络的技术应用与开发对网络的性能要求越来越高.从保证网络可靠性和服务质量角度考虑无线传感器网络性能参数.给出了保障服务质量的网络可靠性数学模型,由于可靠性计算是NP难问题,进一步研究该网络模型的可靠性上界.通过利用点割集代替极小割的方法提出了可靠性上界的计算公式.仿真结果表明,上界结果对评估网络可靠性精确值的近似效果较好.     

一种无线传感器网络电池剩余能量估计算法

无线传感器网络价格便宜、安全可靠,可以部署在不同的环境中越来越受到关注.然而,它们的能量有限,导致寿命有限,提出一种无线传感器电池剩余能量估计算法,对电池剩余能量进行估计.算法是基于模型预测控制的二元最优化变化,通过解决混合整数二次规划(Mixed Integer Quadratic Programming,MIQP)问题来估计电池剩余的能量,实现低成本,低功耗,低计算能力的传感器节点电池剩余能量估计算法.     

无线传感器网络传输可靠性计算

无线传感器网络是由传感器节点和汇聚节点组成的以数据为中心的无线网络.汇聚节点根据一个或多个源节点传送的采集数据对事件进行监测和判断,而数据传输的可靠性直接影响到监测和判断的准确性.在无线传感器网络中,一方面,网络拓扑结构是动态变化的,数据传输的可靠性与网络拓扑结构有关;另一方面,网络中的传感器节点是能最受限的,因此传输的可靠性还与节点的能昔密切相关-针对无线传感器网络的特点,给出了无线传感器网络的传输可靠性概念,提出一种传输可靠性度量,分别在有数据融合和无数据融合两种情况下,对网络节点的能耗情况进行了分析,获得r网络节点正常工作的概率随时间的变化关系,并导出数学表达式,用于计算节点所产生的数据包成功传输给汇聚节点的概率,从而获得了求整个网络传输可靠性的计算方法.     

求解无线传感器网络路由问题的蚁群最优化算法及其收敛性

首先将无线传感器网络的路由问题转化成求解最小Steiner树问题,然后给出了求解无线传感器网络路由的蚁群优化算法,并对算法的收敛性进行了证明．最后对找到最优解后信息素值的变化进行了分析．即在限制信息素取值的条件下,当迭代次数充分大时,该算法能以任意接近于1的概率找到最优解,并且当最优解找到后,最优树边上的信息素单调增加,而最优解以外边上的信息素在有限步达到最小值．     

独立集的度和与图的哈密尔顿性

关于哈密尔顿连通图的一个基本结果是Ore给出的：设G是n阶图,若对于任意两个不相邻顶点u和v,有d(u) d(v)≥n 1,则G是哈密尔顿连通的．设G是一个图,对于任意u (?)V(G),令N(U)=∪_(u∈∪)N(u),d(U)=|N(U)|,称d(U)是U的度．本文利用独立集的度和得到如下结果：设s和t是正整数,G是(2s 2t 1)-连通n阶图．若对于任两个强不交独立集S,T,|S|=s,|T|=t,有d(S) d(T)≥n 1．则G是哈密尔顿连通的．同时也得到图的哈密尔顿性的其它相关结果．两个独立集S和T称为强不交的,如果S∪T也是独立集．     

关于模糊拟阵的独立子集套和独立集函数

本文的研究方法主要是将模糊拟阵问题转化为普通拟阵问题来研究的方法。本文首先建立独立子集套概念,并使用这个概念和独立集函数概念构建了闭模糊拟阵的充要条件和模糊独立集的充要条件;然后,本文仔细分析了模糊基的性质,找到了一个使用独立子集套和独立集函数来描述的模糊基的充要条件;最后,利用模糊基的这个充要条件提出并证明了闭正规模糊拟阵的充要条件。     

一种基于网格模型的无限传感器网络K区域覆盖算法

目前无限传感器网络K覆盖问题的解决机制大都有颇为苛刻的假设条件,如要求节点具有很强的能量、节点的感知区域能被精确定义等.提出了一个基于布尔感知理论的分布式网格模型及相应的K区域覆盖算法,能够很好地处理感知区域形状不规则及大小发生变化的K覆盖问题,算法时间复杂度小,适用范围广泛.仿真实验证明了算法的有效性.     

Two Remarks on Independent Sets

In the first part we generalize the notion of strongly independent sets, introduced in [10] for polynomial ideals, to submodules of free modules and explain their computational relevance. We discuss also two algorithms to compute strongly independent sets that rest on the primary decomposition of squarefree monomial ideals.Usually the initial ideal in(I) of a polynomial ideal I is worse than I. In [9] the authors observed that nevertheless in(I) is not as bad as one should expect, showing that in(I) is connected in codimension one if I is prime.In the second part of the paper we add more evidence to that observation. We show that in(I) inherits (radically) unmixedness, connectedness in codimension one and connectedness outside a finite set of points from I and prove the same results also for initial submodules of free modules. The proofs use a deformation from I to in(I ).     

AIS Based Distributed Wireless Sensor Network for Mobile Search and Rescue Robot Tracking

This research presents the implementation of GSCF, an AIS-based control framework, on a distributed wireless sensor network for tracking search and rescue robots in open fields. The General Suppression Control Framework (GSCF) is a framework inspired by the suppression hypothesis of the immune discrimination theory. The framework consists of five distinct components; each carries a specific function that can generate long-term and short-term influences to other components by the use of humoral and cellular signals. The goal of the research is to develop mathematical models that can assist the control and analyses of robots behavior through the use of Suppressor Cells in the Suppression Modulator. Acquire data from the physical robot will be used as simulation parameters in future search and rescue research.     

直线簇上区间图的最小独立控制集

本文研究了在三种情况下直线上的区间图的最小独立控制集的计算问题:1．相交于一点的直线簇,2．除一条直线外,其余的直线都平行的直线簇,3．一条直线和直线上t个赋权的点,使得其最小独立控制集所覆盖的点的权和最大．本文给出了这三个问题的多项式时间算法,问题1可以在O(n)时间内求解,借助动态规划方法问题2和问题 3分别可以在O(n log n),O(n t)时间内求解．     

Counting Independent Sets of a Fixed Size in Graphs with a Given Minimum Degree

Galvin showed that for all fixed δ and sufficiently large n, the n‐vertex graph with minimum degree δ that admits the most independent sets is the complete bipartite graph . He conjectured that except perhaps for some small values of t, the same graph yields the maximum count of independent sets of size t for each possible t. Evidence for this conjecture was recently provided by Alexander, Cutler, and Mink, who showed that for all triples with , no n‐vertex bipartite graph with minimum degree δ admits more independent sets of size t than . Here, we make further progress. We show that for all triples with and , no n‐vertex graph with minimum degree δ admits more independent sets of size t than , and we obtain the same conclusion for and . Our proofs lead us naturally to the study of an interesting family of critical graphs, namely those of minimum degree δ whose minimum degree drops on deletion of an edge or a vertex.     

基于ZigBee的工业控制网络模型

将无线传感器网络技术成功应用于工业自动化,建立了基于ZigBee的工业控制网络模型,并成功应用于生产线的工业控制中.     

A Note on the Approximation of a Minimum-Weight Maximal Independent Set

We consider the polynomial approximation behavior of the problem of finding, in a graph with weighted vertices, a maximal independent set minimizing the sum of the weights. In the spirit of a work of Halldórson dealing with the unweighted case, we extend it and perform approximation hardness results by using a reduction from the minimum coloring problem. In particular, a consequence of our main result is that there does not exist any polynomial time algorithm approximating this problem within a ratio independent of the weights, unless P = NP. We bring also to the fore a very simple ratio guaranteed by every algorithm while no polynomial time algorithm can guarantee the ratio (1 – ). The known hardness results for the unweighted case can be deduced. We finally discuss approximation results for both weighted and unweighted cases: we perform an approximation ratio that is valid for any algorithm for the former and propose an analysis of a greedy algorithm for the latter.     

A Markov Renewal Based Model for Wireless Networks

We propose a queueing network model which can be used for the integration of the mobility and teletraffic aspects that are characteristic of wireless networks. In the general case, the model is an open network of infinite server queues where customers arrive according to a non-homogeneous Poisson process. The movement of a customer in the network is described by a Markov renewal process. Moreover, customers have attributes, such as a teletraffic state, that are driven by continuous time Markov chains and, therefore, change as they move through the network. We investigate the transient and limit number of customers in disjoint sets of nodes and attributes. These turn out to be independent Poisson random variables. We also calculate the covariances of the number of customers in two sets of nodes and attributes at different time epochs. Moreover, we conclude that the arrival process per attribute to a node is the sum of independent Poisson cluster processes and derive its univariate probability generating function. In addition, the arrival process to an outside node of the network is a non-homogeneous Poisson process. We illustrate the applications of the queueing network model and the results derived in a particular wireless network.     

几何随机图大连通分支覆盖面积及其在传感器网络中的应用

随机网络中的大连通分支能体现一个网络的连通情况,是几何随机图研究的-个热点,具有重要的理论意义和应用价值.本文利用渗流理论,研究了几何随机图大连通分支覆盖面积所具有的性质,并将理论结果应用到大型无线传感器网络中,研究了无线传感器网络覆盖的性质.研究结果表明,对于节点服从泊松分布的大型无线传感器网络,其大连通分支覆盖区域大小与总区域大小的比值趋于-个常数,且并估计出了2维空间中没有被大连通分支所覆盖的连通区域(本文称为空洞)的大小.这些结果为衡量无线传感器网络性能提供了理论基础,对实际布网和网络优化等具有一定的指导意义.     

P2P环境下基于WSN和RFID的供应链管理语义监控平台

提出了一种基于语义P2P的无线传感器网络应用架构,在此架构下融合了RFID技术提出了供应链管理的语义监控平台.该平台采用语义P2P技术解决了信息过载通信瓶颈问题,方便了传感器节点部署、使得传感器网络易于扩展,同时采用本体技术实现了供应链管理中的信息语义交互和共享,为供应链中信息的及时、无歧义理解提供了便利.