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1.
The construction of multirate rearrangeable network has long been an interesting problem. Of many results published, all were achieved on 3-stage Clos network. The monotone routing algorithm proposed by Huet al. (2001) was also first applied to 3-stage Clos network. In this work, we adopt this algorithm and apply it to log d (N,m,p) networks. We first analyze the properties of log d (N,m,p) networks. Then we use monotone algorithm in log d (N,0,p) network. Furthermore we extend the result to construct multirate rearrangeable networks based on log d (N,m,p) network (1≤m≤n−1). Project (No. 10371028) supported by the National Natural Science Foundation of China  相似文献   

2.
对于任意的实数p,两正数a与b的幂平均定义如下:Mp(a,b)=(ap 2+bp)1p p≠0槡ab p={0,以下将证明:对所有a,b〉0,m∈(0,32)有如下的不等式:1)当m∈(0,32)时,M log2log3(m+2)-log2(a,b)≤23 Hm(a,b)+13 G(a,b)≤M 3(m4+2)(a,b);2)当m∈[23,+∞)时,M 43(m+2)(a,b)≤32 Hm(a,b)+31 G(a,b)≤M log3(mlo+g22)-log2(a,b)。其中当且仅当a=b时,等号成立,同时参数23(m+2),l og3(m l+o g22)-log2对于不等式是最优的临界值。给予两正数a,b的海伦平均,几何平均分别如下:Hm=a+bm++m 2槡ab,G(a,b)=槡ab。  相似文献   

3.
以Nn+p表示其截面曲率KN 满足 0 <δ≤KN≤ 1的n +p维局部对称完备黎曼流形 ,Mn 是Nn+ p的n维极小子流形 ,本文研究这类子流形的截面曲率的Pinching问题  相似文献   

4.
利用概率向量给出了m-ary n-cube的一种新的容错路由.为了计算这个概率向量,应该首先确定其k一级不安全结点集Sk(1≤k≤n),即从源结点}}{发由于顶点故障或边故障而不能通信的距离为k的目的结点.在确定这些不安全结点集研后,给出一个概率向量的计算方法,随后确定容错路由.  相似文献   

5.
Nonrecursive structural equation models generally take the form of feedback loops, involving 2 latent variables that are connected by 2 unidirectional paths, 1 starting with each variable and terminating in the other variable. Nonrecursive models belong to a larger class of path models that require the use of instrumental variables (IVs) to achieve model identification. Prior research has focused on SEM parameter estimation with IVs when indicators were continuous and normally distributed. Much less is known about how estimators function in the presence of categorical indicators, which are commonly used in the social sciences, such as with cognitive and affective instruments. In this study, there was specific interest in comparing the 2-stage least squares (2SLS) estimator and its categorical variant to other recommended estimators. This study compares the performance of several estimation approaches for fitting structural equation models with categorical indicator variables when IVs are necessary to obtain proper model estimates. Across conditions, 1 extension of the nonlinear 2SLS (N2SLS) approach, the nonlinear 3-stage least squares (N3SLS), which accounts for correlated errors among regressors within each model (as does the N2SLS), as well as correlations of errors across models, which N2SLS does not, appears to work the best among methods compared.  相似文献   

6.
近年来,许多关于社区发现的优秀算法被提出并取得了较好的社区划分效果。但是到目前为止,没有任何一种算法能够同时在时间复杂度和准确度方面取得较好的表现。现实网络中往往存在一些有利于指导社区发现的标签信息,如must-link信息、cannot-link信息等。因此提出基于少量标签信息传播、拓扑结构的半监督社区发现算法S_LPA,分别在karate网络、dolphins网络、LFR基准网络上进行测试。实验结果表明,该算法S_LPA时间复杂度为O(m),相对其它算法,S_LPA在karate网络和dolphins网络的NMI值高于CNM、InfoMap、LPA算法,在LRF网络上准确度高出约20%;提高参数u后,S_LPA算法可识别其它算法不能识别的社区结构。  相似文献   

7.
设Nn + p是截面曲率KN 满足 12 <δ≤KN≤ 1的n +p维局部对称完备黎曼流形 ,P≥ 1.M是Nn + p的具有平行中曲率向量的n维紧致子流形 ,本文讨论了这类子流形关于第二基本形式模长平方的积分不等式及其Pinching问题 .  相似文献   

8.
对无线个域网应用环境下采用跳频方案的蓝牙网络和IEEE 802.1lFHSS网络之间的共存性问题进行了研究,通过容量分析和系统仿真,比较了它们的相互影响.在此基础上,提出了采用包负荷长度分段自适应的方法来提高IEEE802.1lFHSS网络的抗干扰性能,并对所提方案进行了分析仿真.结果表明,IEEE802.11WLAN标准的内在机制能够支持本提出的方法,改善了抗干扰的鲁棒性,并且随着蓝牙干扰网络数量的增加,采用自适应方案的IEEE802.1lFHSS网络的抗干扰性能明显增强,网络容量的下降得到有效缓解.中所采用的容量分析和包负荷长度分段自适应方案也可以推广到其他FHSS网络.  相似文献   

9.
研究了工件有优先约束和尺寸大小关系的分批排序问题,这里目标函数为工件的极大完工时间,这类问题是NP—完备的.对工件加工时间相同和有特殊到达时间的情况给出了它的近似算法,并证明其最差性能比不超过2.  相似文献   

10.
对Hardy-Hilbert不等式进行了研究,并将其进一步改进如下:若p〉1,1/p+1/q=1,0〈A,B≤1,an,bn≥0,使0〈∑∞n=0apn〈∞,0〈∑∞n=0bqn〈∞,则∑∞m=0∑∞n=0ambn/Am+Bn+1〈{∑∞n=0(π/Bsin(π/p)-(3p-B)( p-1)/6p(2An+)11/p)anp}1/p{∑∞n=0(π/Asin(π/p)-(3q-A)(q-1)/6q(2Bn+1)1/q)bnq}1/q.所得结果改进和推广了最近文献的一些相应结果.  相似文献   

11.
利用李雅普诺夫泛函和不等式Zm+ 1∏k=1^m zk^qk≤1/r ∑k=1^m qkZk^r+1/rzm+1^r 研究了一类BAMCG模型的周期解,并获得了一些充分条件.这些结果推广了已有文献的结论.  相似文献   

12.
Educational networks constitute a new way of governance, which aims at collaborating on current challenges in the educational system. Such networks are based on the social relationships of their members, whereby trust is of particular relevance. In this article, we focus on this interpersonal trust within an educational network and take a first step towards an empirically grounded theory on dimensions of trust in a multi-organizational coalition. To that end, we analyze semi-structured interviews with a total of 21 actors of an exemplary educational network. The interviews were mainly focused on the interviewees’ network relationships. These relationships were analyzed by means of Grounded Theory using the data analysis software MAXQDA. Our analyses resulted in a theory of five dimensions of trust: (1) individual attitude, (2) time, (3) organizational and issue-specific proximity, (4) power, and (5) multiplexity. These dimensions represent an approximation of a better understanding of trustful relations in educational networks and have to be verified in further – particularly representative – studies for their validity.  相似文献   

13.
笛卡尔积图P_m×P_n的IC-着色   总被引:1,自引:1,他引:0  
设G是一个连通图,f个将顶点集V G对应到正整数集N的函数,对G的任意子图H,我们定义fs H=Σν∈V(H)fν。如果对任意的整数k∈Σ1,fs GΣ,存在一个G的连通子图H,使得fs H=k,则称f为图G的一个IC-着色。并定义图G的IC-指数M G为使得顶点和最大时的fs G。对两条路的笛卡尔图的IC-着色进行研究,得到了它的一个下界:对任意的2≤m≤n,有M Pm×Pn≥2m-1 2n-1。  相似文献   

14.
互联网络RCP(Ringed Crossed cube Petersen)拓扑结构被提出后并没有给出组播算法.本文利用RCP(n)网络的正则性、良好的可扩展性,以及比Qn,HP(n),RHP(n)网络直径更短和构造开销更小这些特性,按照构造组播树的方法,给出了RCP(n)网络的组播路由算法,并对该算法作了性能分析.  相似文献   

15.
The 3rd generation partnership project (3GPP) has defined the protocols and codecs for implementing media streaming services over packet-switched 3G mobile networks. The specification is based on IETF RFCs on audio/video transport. It also adds new features to achieve better adaptation to the mobile network environment. In this paper, we propose an algorithm for handover detection and fast buffer refill that is based on the existing feedback and signaling mechanisms. The proposed algorithm refills the receiver buffer at a faster pace during a limited time frame after a hard handover is detected in order to achieve higher video quality.  相似文献   

16.
广义动态神经网络的绝对指数稳定性   总被引:1,自引:0,他引:1  
本研究了一类具偏李普希兹连续和单调增加激活函数的神经网络绝对指数稳定性问题。所得结果归结为如果联接矩阵T的负矩阵是一个非负对角元的H矩阵,那么在任意输入向量和网络参数的条件下,所选激活函数只要是偏李普希兹连续且单调增加的,广义动态神经网络绝对指数稳定。该广义动态神经网络包含常用的Hopfield神经网络,双向联想记忆神经网络和细胞神经网络作为其特殊情形,所得结论推广了现有献中的有关结论。  相似文献   

17.
本文主要处理非局部波动方程组解的全局存在与爆破问题,考虑如下非局部波动方程组的初值问题:{δ^2u1/δt^2=δ^2u1/δx^2+‖u2(·,t)‖p1,δ^2u2/δt^2+‖u3(·,t)‖p2,δ^2u3/δt^2=δ^2u3/δx^2+‖u1(·,t)‖p3,-∞〈x〈∞,t〉0 ui(x,0)=fi(x),δui/δt(x,0)=gi(x),i=1,2,3,-∞〈x〈∞ 这里0〈p1,p2,p3〈+∞,‖ui(·,t)‖=∫-∞^+∞ φi(x)|u(x,t)|dx,i=1,2,3,其中φi(x)≥∫-∞^+∞ φi(x)dx=1,i=1,2,3。所有这些初值函数都为连续的且|fi(x)|+|gi(x)|恒不等于0,i=1,2,3.根据对称性,本文假定p1≤p2≤p3.  相似文献   

18.
为了使一个10 Gbit/s 2∶1半速率复接器电路能够在无外部提供时钟的环境中工作,需要一个5 Gbit/s时钟恢复电路从一路输入数据中提取出所需时钟.该时钟恢复电路采用3级环形压控振荡器,以克服2级振荡器存在的起振不可靠和4级振荡器振荡频率低的问题;采用鉴频鉴相器来增加牵引范围,以适应由于工艺、电压及温度偏差等原因...  相似文献   

19.
Let K be a 1-unconditional convex bodies in Euclidean spaces. We study the asymptotic properties of two affine invariants m2(K) and S2(K) for a random simplex inside K. As an application, we discuss the asymptotic properties of two affine invariants m2(Bnp) and S2(Bnp), where Bnp = {χ∈ Rn: ‖χ‖p ≤ 1}.  相似文献   

20.
本文研究局部对称共形平坦黎曼流形的具有平行非零中曲率向量的焦脐点子流形的截面曲率和数量曲率的拼挤问题。  相似文献   

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