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1.
设G是简单连通图,r_n~c(G)和ir_n(G)分别表示图G的连通n-Domination数和n-Irredundance数、本文证明了如下结论:r_n~c(G)≤(3n+1)ir_n(G)-2n。  相似文献   

2.
设u、v是两个固定顶点,用b条内部互不相交且长度均为a的道路连接u、v所得到的图用Pa,b表示.Kathiresan证实P2r,2m-1(r,m均为任意正整数)是优美的,且猜想除了(a,b)=(2r+1,4s+2)外,所有的Pa,b都是优美的.杨元生已证实P2r+1,2m-1是优美的.本文证明P3,4m是优美图,从而当a=3时Kathiresan猜想成立.  相似文献   

3.
具有正交(g,f)-因子分解的子图   总被引:3,自引:0,他引:3       下载免费PDF全文
设G是一个图 ,g (x)和f (x)是定义在V (G)上的整数值函数 ,且对任意的x∈V (G) ,设g (x)≤f (x) ,H是G的一个子图 ,F ={F1,F2 ,… ,Ft}是G的一个因子分解 ,如果对任意的 1≤i≤t,|E (H)∩E (Fi) |=1 ,则称F与H正交。闫桂英和潘教峰在文 [3]中提出如下猜想 :设G是一个 (mg+k,mf-k) -图 ,1≤k相似文献   

4.
文中证明了定理:若图G中不存在与K_4同胚的子图,则其色数X(G)≤3,进而得到三色图的一个充分条件。只要能证明与上述定理类似的一个定理:“若图G中不存在与K_5同胚的子图,则其色数X(G)≤4”,则世界著名的“四色猜想(4CC)”即得证。  相似文献   

5.
设H是一个超图(图),对于它的一个k边着色c:E(H)→{1,2,∧k},我们记f(H,c)是由k种颜色中,由同一色类导出的子超图(子图)中所含分枝数最少的子超图(子图)的分枝数。fk(H)表示H中所有k边着色中f(H,c)的最大值,即fk(H)=maxf(H,c)。本文主要研究了路、Ti’、广义θ-图的成分着色,并得到了fi(Pn)=(n-1/k,f(Ti^*)=[i-1/k]+1∫k(Gθ)=2  相似文献   

6.
一、射击弹道微分方程组的建立:式中:J—空气阻力加速度矢量; g—重力加速度矢量。 由外弹道学可知,空气阻力加速度矢量为: J=一CH(y)G(厂)V式中:C—弹丸的弹道系数。 将质心运动矢量方程式在斜坐标系重O刀中投影,可得到质心运动方程组为:草冥=一cH(,,G(犷’U U名d万 d考=一CH(y)G(厂)矿十g厂l吸111!11!11二wees、 空中射击弹道示意图 图中符号:O一发射点,C一命中点,M一弹道上任意一点;H一发射点‘0距地面的高度;Y一M点距地面的高度,H一斜距离(即距离OM);刀一弹道降低量,。一目标高低角;a一抬高角,701一弹丸的绝对初速矢量,V弹丸…  相似文献   

7.
根据部分多值逻辑完备性理论,证明了当m=2时,若正则可离关系G2=G2({1,2})∪G2之关系图仅是一个回路,则T(G2)不是P k的最小覆盖成员.  相似文献   

8.
应用非标准方法研究由内集 E 上的超实度量所导出的 Q—拓扑与 S—拓扑,给出这两种拓扑的一些重要性质:(E,Q)是完全不连通的且其紧子集都是有限集;G(X)/关于 E 上的 S—拓扑的商拓扑是可度量化且完备的;G(X)的有界子集 A 若满足A/是 S—拓扑的商空间G(X)/的闭子集,则 A 是 S—紧的,本文还讨论了 S—拓扑在构造完备度量空间的应用。  相似文献   

9.
M/G/1(RVT,P(j))表示服务员具有随机长度休息时间(RVT)的、且一休息时间结束时有 j 个顾客等待的概率为 P(j)的、修正的 M/G/1 排队系统。我们用嵌入 Markov 链的技术已详细地分析过这一排队系统,这里提供另一分析方法。最后,应用这个排队系统的分析结果,对时隙 ALOHA 卫星公用信道的分组碰撞概率计算公式作了推导。  相似文献   

10.
字符发生器是信息显示(文字和图形)设备中不可缺少和极为重要的功能发生器。它的功能是将以数字编码形式表示的字符变换成为图形表示的字符。图1示出它的基本结构图。  相似文献   

11.
对任意正整数n,Pd(n)定义为n的所有正因子的乘积,gd(n)定义为n的所有小于n的正因子的乘积。若n=p1^a1p2^a2…px^as是n的标准分解式,算数函数Ω(n)=a1+a2+…+as。用解析的方法研究关于Smarandache序列Pd(n)、qd(n)与Q(n)的混合均值,并给出两个较好的渐近公式。  相似文献   

12.
We consider an integrated usage and maintenance optimization problem for a k‐out‐of‐n system pertaining to a moving asset. The k‐out‐of‐n systems are commonly utilized in practice to increase availability, where n denotes the total number of parallel and identical units and k the number of units required to be active for a functional system. Moving assets such as aircraft, ships, and submarines are subject to different operating modes. Operating modes can dictate not only the number of system units that are needed to be active, but also where the moving asset physically is, and under which environmental conditions it operates. We use the intrinsic age concept to model the degradation process. The intrinsic age is analogous to an intrinsic clock which ticks on a different pace in different operating modes. In our problem setting, the number of active units, degradation rates of active and standby units, maintenance costs, and type of economic dependencies are functions of operating modes. In each operating mode, the decision maker should decide on the set of units to activate (usage decision) and the set of units to maintain (maintenance decision). Since the degradation rate differs for active and standby units, the units to be maintained depend on the units that have been activated, and vice versa. In order to minimize maintenance costs, usage and maintenance decisions should be jointly optimized. We formulate this problem as a Markov decision process and provide some structural properties of the optimal policy. Moreover, we assess the performance of usage policies that are commonly implemented for maritime systems. We show that the cost increase resulting from these policies is up to 27% for realistic settings. Our numerical experiments demonstrate the cases in which joint usage and maintenance optimization is more valuable. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 418–434, 2017  相似文献   

13.
Impact velocity (v0), target strength (fc) and target thickness (hc) are important factors affecting opening damage ((D)) of PELE penetration into RC target. In this paper, based on the three influence factors of v0, fc and hc, experimental and numerical simulation studies on PELE penetration into RC target were carried out. The study results show that: (1) Since interaction force (or penetration resistance) between pro-jectile and target is positively correlated with v0 and fc, with the increase of v0 and fc, deformation mode of jacket is changed from small bending deformation to large bending deformation and then to curling deformation. Therefore, the variation of jacket deformation mode causes opening diameter of RC target to increase first and then to decrease. It is found that the two factors approximately satisfy a quadratic function relationship, respectively. (2) For PELE projectile penetrating RC targets with thickness of 80—400 mm, the opening diameter of six sets of RC targets grows from 240 to 500 mm, and hc with (D) approximately satisfy a linear relationship. (3) Based on the above study results, the relationship be-tween two dimensionless parameters (I= (mv20/d31fc) and H= hc/l ) and dimensionless opening diameter ((D)/d1) was determined. Combined with the results of previous research, a dimensionless opening diameter model (D)/d1=f1(Q,G,I)f2(H) was established. By tests verified, the test results are all within ±10%error of the theoretical model, which verifies the accuracy of the model.  相似文献   

14.
战斗机指挥引导中的威力场模型   总被引:2,自引:0,他引:2  
场在自然界是普遍存在的,战斗机之间也存在类似的相互作用.提出战斗机威力场概念,建立威力场的理论框架与模型.战斗机威力场产生两种势:斥力势与引力势.斥力势表示由战斗机产生的排斥其他物体接近的作用.引力势是指战斗机的各种威力对周围空间产生的影响.分别建立斥力势和引力势的计算模型.引力势模型由6个部分构成:方向、目标探测、攻击、到达、电子对抗和通信,我机产生的引力势为正,敌机为负.两种势在整个空间都具有可叠加性.应用威力场理论对战斗机安全距离控制、态势评估和战斗机引导控制等进行了分析.最后通过仿真算例来验证该理论.#  相似文献   

15.
This paper introduces an extension of the v. Neumann model of an expanding economy. In addition to the conventional nonnegative input and output matrices A1, B1 representing technology, two matrices A2, B2 represent socio-political evaluations and show that there exist solutions to the 4-matrix model. The proof is based on an extension of a constructive proof given by O. Morgenstern and G. L. Thompson. It is shown that this proof is valid only under an additional assumption. The transformation of v. Neumann models (taking consumption into account) into 1 or 2 games is shown and adds an additional condition to M. Morishima's model to guarantee a solution. The equivalence of the v. Neumann model to a maximization problem under a (efficiency) constraint is presented. It is shown that E. Malinvaud's maximality and efficiency criterion - if based on the same assumptions (model) - are equivalent and specify the assumptions which will make the MT-model efficient. The economic evaluation is considered to be of utmost importance.  相似文献   

16.
中国的“和合”文化历史非常悠久,有着鲜明的民族特色和丰富的文化内涵。“和合”在管理学上的要义是:“和”与“合”的联用构成了一个充满哲理性、辩证性的概念,表示了身心和谐、和睦相处、合作致胜的管理理念和管理方式。基于东方管理“人为为人”精髓,本文提出了由“己身和合”到“群己和合”再到“组织和合”的和合管理。  相似文献   

17.
The opportunistic maintenance of a k‐out‐of‐n:G system with imperfect preventive maintenance (PM) is studied in this paper, where partial failure is allowed. In many applications, the optimal maintenance actions for one component often depend on the states of the other components and system reliability requirements. Two new (τ, T) opportunistic maintenance models with the consideration of reliability requirements are proposed. In these two models, only minimal repairs are performed on failed components before time τ and the corrective maintenance (CM) of all failed components are combined with PM of all functioning but deteriorated components after τ; if the system survives to time T without perfect maintenance, it will be subject to PM at time T. Considering maintenance time, asymptotic system cost rate and availability are derived. The results obtained generalize and unify some previous research in this area. Application to aircraft engine maintenance is presented. © 2000 John Wiley & Sons;, Inc. Naval Research Logistics 47: 223–239, 2000  相似文献   

18.
由于数据不足,在全寿命周期的初始阶段使用传统的可靠性分析技术,难以对装备的贮存可靠性进行研究。在模糊集理论的基础上,应用L-R型模糊数的模糊故障树分析技术,探讨了装备贮存可靠性的研究问题。  相似文献   

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