查询词典 underlying graph

The aim of this paper is to draw a general perspective of the liveness and safeness for a subclass with Extended Free Choice net-like underlying graph but allowing weights:Weighted Extended Free Choice nets.

该文贡献在于为一种称为加权扩充自由选择网的网系统子类找到活性与安全性的一般性质。

Based on underlying routing graph, the proposed scheme allows each node to locally select communication neighbors and dynamically adjust its transmission radius accordingly, such that all nodes together self-form an energy-efficient topology.

该协议以移动WSN能量优化为目标，采用计算几何数学模型工具构造协议路由图，使得网络节点只需要在本地选择通信邻居并动态调整传输半径，来构造一个全局能量有效的路由拓扑。

With the rapid development of information networks, many theoreticalproblems come into focus, one of which is the reliability of the network, thatis, the ability of the network to function even when some vertices and/or edgesfail. The underlying topology of a network is often modeled as a graph.

随着信息网络的飞速发展，许多相关的理论问题开始引起人们的重视，其中之一是网络的可靠性，即网络在它的某些部件发生故障的条件下仍能工作的能力。

In mobile Ad Hoc networks, geographical routing protocol was a kind of important routing protocols, which requires the underlying topology be planar, sparse, connected and t-spanner in order to guarantee the delivery of message and bound the routing length. A new topology control algorithm named ODT, which constructed the geometry structure named ODT graph, was proposed.

基于移动Ad Hoc网络的特性，提出了一种适用于移动Ad Hoc网络的路由协议PAGPSR(Power-Aware Greedy Perimeter Stateless Routing)，该协议在原有的基于地理位置的路由协议GPSR的基础上增加了节点能量感知和负载均衡算法，修改了GPSR的转发策略，使网络中能量消耗和网络负荷分布更加均匀，从而延长了整个网络的生存时间。

Primarily, the thesis assays the condition of network framework, the network was divided into three levels in terms of network management in order to establish the distributed method ,and still pointing out the intention and denotation of studying the Topology Discovery.Next, the thesis analyzes SNMP protocol minutely, including its development, principle, and the Network Management system that established on the SNMP protocol. Have analysed MIB in detail and the application way of MIB in network management .The thesis also assays the ICMP protocol, describing its working principle and the format of datagram minutely , and describing two important tools of ICMP- Ping and TraceRoute in detail. On the base of upper analysis, the thesis expounds a kind of distributed Topology Discovery project, and book it in one autonomy system. Topology Discovery was divided into two levels in terms of network management, and analyses the way of linking up between the two level. The thesis minutely assays Router-Level Topology Discovery technology basing on SNMP and Subnet-Level Topology Discovery technology basing on ARP and ICMP. According to these analyses, the thesis explores the specific methodology and the technology of XML data object which using the WinSNMP API to achieve topology discovering system on the development platform of Visual C++, and also analyses the technology of topology analysis and topology graph minutely. Moreover, the thesis assays the technology of basic firewall and Topology Discovery response strategy. Finally, the thesis analyses the underlying blind problem of the topology finding, and also analyses the reason that the blind problem produced and the way that reduced. The distributed algorithm that this paper puts forward has a certain directive significance in wireless network or other fields.

本文首先分析了网络结构状况，将网络从网络管理的角度划分为三个层次，为分布式的方法奠定了基础，同时还指出拓扑发现研究的目的及意义；接着本文分析了SNMP协议，详细分析了SNMP协议的发展状况，协议的工作原理，以及由SNMP协议基础上建立的SNMP网络管理体系，详细分析了MIB，以及MIB在网络管理上的应用方式；本文又分析了ICMP协议，详细描述了ICMP的工作原理和数据报格式，并详细描述了ICMP的两个重要工具-Ping 和TraceRoute；然后本文在结合上述分析的基础上，提出了一种分布式的拓扑发现方案，将拓扑发现拟订在一个自治系统内，将拓扑发现从网络管理角度划分为路由器级和子网级两个层次，分析了两个层次之间的衔接方式，同时从拓扑地域的角度将拓扑发现过程分布化，分析了分布式算法的具体方法和分布式结点之间的数据通讯方法，本文详细分析了基于SNMP的路由器级拓扑发现技术和基于ARP和ICMP的子网级拓扑发现技术；根据这些分析，本文利用XML数据对象作为分布式算法中的数据对象，分析了XML的技术，本文使用Visual C++开发平台实现网络拓扑发现系统，详细分析了使用WinSNMP API实现基于SNMP的路由器级拓扑发现和基于ARP的子网级拓扑发现，分析了使用Winsock编程实现基于ICMP的子网级拓扑发现，本文还对拓扑分析和拓扑图的绘制技术作了较细致的分析；本文最后还分析了基本防火墙技术，分析了几种类型的防火墙对拓扑发现带来的影响，以及在拓扑发现时的应对策略，本文还分析了拓扑发现中可能产生的盲点问题，分析了盲点产生的原因以及拓扑发现中减少盲点的方法。

In parallel to PN, chapter 4 defines a series of concepts for timed PNs with weak firing rules , gives generative approaches for state reachable graph and state coverable graph, and proves that WTPN is equivalent to its underlying net about liveness, boundedness and reversibility.

第三章除简介PN的基本知识，还分析了现有的四种确定性时间约束PN与其基网系统之间关系，指出了它们用于定性分析和性能评估时出现的一些问题及其产生的原因，比较了它们的异同并指出了一些现存关于它们的模糊认识以及由此产生的不妥结论，基于此提出并初步探讨了四种LDTCPN模型与其基网系统的关系。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。