无向图

Sequential dynamical system; functional digraph ; orbit ; width ; periodic point ; fixed point ; invertible ; matrix ; Markov chain ; adaptive ; acyclic orientation ; word ; C-pseud independent set ; random graph

南开大学；郑洁贯序动力系统；像图；轨道；宽度；周期点；固定点；可逆；矩阵；马氏链；适应；无圈定向；字； C-伪独立集；随机图

The problem of deciding whether an arbitrary undirected planar graph $G$ is a Hamiltonian is one of six best important {bf NP}-complete problems.

判定一个任意的无向可平面图G是否是哈密顿图问题是六个重要的NP完全问题之一。

In this thesis, we consider only finite, undirected and simple graph G = of order n.

在这篇论文中，我们只考虑阶数为n的有限，无向简单图G=。

The structure shown in the figure : The governing body received direct or roller drying cylinder, as the main components of the rotation; After finishing the outside of the sphere, Bottom Cover and soak spherical carbon graphite seal ring joint seal reliable seal friction deputy, Sealing ring in the spherical shell of its annular space sliding, in addition to oil-free bearings and with the close cooperation of Shell, Rotating connector so that the free support, and therefore do not require a high level of accuracy installed; Spherical seal ring wear, Spring means of pressure at any time in advance to receive compensation, compensation for the shell slowly moved backward, accessible through the tube outside the inscription on the line to observe the seals wear; When steam, Oil flows through the media or other spherical sealing ring and oil-free bearings, the formation of thin liquid film, sealing and lubrication, thereby reducing friction and wear, extending the service life.

其结构如图所示：外管体直接接到辊子或烘筒上，为主要的旋转部件；经过精加工的外管本球面、底盖和浸泡碳石墨球面密封环共同组成密封可靠的动密封磨擦副，球面密封环在其壳体内的环形空间中滑动，加之无油轴承与壳体的密切配合，使旋转接头自由支撑，故对装机精度要求不高；球面密封环磨损后，借助于弹簧的预压力随时得到补偿，补偿时壳体缓缓向后移动，并可通过外管体上的刻线观察到密封件的磨损程度；当蒸汽、油或其它介质流经球面密封环和无油轴承时，形成一层很薄的液膜，提供密封和润滑，从而减轻了摩擦和磨损，延长了使用寿命。

This paper gave a review of recent developments in the study of nullities of undirected simple graphs.

综述无向简单图零度问题近年来所取得的研究进展。

After survey, we study the wide-diameters of undirected de Bruijn graphs in Chapter 3, and

在一般性的纵览之后，就进入第三章；虽然无向迪布恩图的连通性早就知道了，但是宽直径却一直不得而知，在这一章中，我们探讨宽直径，从而保证对任意两点都有足够多条的不同路径，而这些路径都不会太长。

Firstly, by means of the algorithm, a model of tourism route analysing was built after taking some hypotheses and predigestion, secondly, a indirected graph for tourism route analysing was generated via the information about travel industry sites, information about roads and finally this algorithm was investigated by adopting the motheds of giving all conditions and Dijkstra algorithm.

该算法通过一定的假设和简化建立旅游路线分析模型，利用旅游景点信息和公路信息生成旅游路线分析无向加权连通图。

This contributes to the rigidity of the bearing and a precise radial guidance of the shaft. For special applications, full-complement cylindrical roller bearings are employed. The cylindrical roller bearing designs are shown in Figures 1.20 and 1.21.The designs of cylindrical roller bearings are distinguished by the arrangement of the lips. Design NU (Figure 1.21b) has two lips on the outer ring, the inner ring being lipless. In design N (Figure 1.21a), the inner ring has two lips, the outer ring has none. Cylindrical roller bearings of designs NU and N are applied as floating bearings because the rollers can freely shift on the lipless ring in the axial direction. Cylindrical roller bearings NJ (Figure 1.20) have two lips on the outer ring and one on the inner ring; they can take up axial forces in one direction. Design NUP (Figure 1.21d) is installed as a locating bearing to sustain frequently reversing axial forces.

这可以提高轴承的刚度，和主轴精密的径向引导，对于特别的运用，密排的圆柱滚子轴承被运用，圆柱轴承的图样在图。20和1.21展示圆柱滚子轴承图样由挡边的不知来区分，图样NU(图1.21b)在外圈有两个挡边，内圈无挡边，在图样N中内圈有两个挡边，外圈无挡边，图样NU和U所示的圆柱滚子轴承可制作浮动轴承因为滚子能够在轴向无挡边环上自由的移动，圆柱滚子轴承NG在外圈上有两个挡边，内圈上有一个，它们能够在某个方向上承受轴向力，图样NUP（图1.21d）被用来安装在一个保持经常扭转轴向力的固定轴承上。

Give a simple undirect regular graph X.

设X是简单无向正则图。

The workflow deadline can be transformed into the time intervals of all tasks based on BL groups, a bottom leveling based algorithm called DBL is proposed.

有向无环图DAG描述的工作流时间费用优化问题是计算网格下一个基本的且难以求解的问题。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。