网络分析

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。

For about 20 years,lots of boffins have do their best in the field,the system reliability theory has made a prominently progress,and produced many theories and methods one after another.

主要以概率论、随机过程论、决策论、博弈论、组合数学和近代数理统计方法为基础，通过有限元、边界元法和随机网络分析技术为计算手段，二十多年来，经过大量科研工作者的辛勤努力，使得系统可靠性理论取得了令人瞩目的成绩，相继提出了多种理论方法。

NAMS? Network Analysis and Management System?

网络分析管理系统

NDT? NAMS Data Type?

网络分析管理系统的数据类型

According to the Guangxi Sugar Network Analysis of the experts said that although the sugar cane plant costs have increased, but the original production in a variety of support materials have also experienced rising cases is bound to will greatly enhance the cost of sugar production.

据广西糖业网络分析专家表示，虽然甘蔗生产成本增加，但在一个辅助材料原有的生产也经历上升的案件，势必将大大提高食糖的生产成本。

To the problem of the head down bending of plate, the influence laws of process parameters, such as the thickness of piece, rolling temperature, ratio of upper and lower roll rotate speed and reduction, on the head -bending direction and degree are found out by test and artificial neural network analysis.

针对中厚板轧制中头部弯曲问题，通过试验模拟及人工神经网络分析，找出了轧件厚度、轧制温度、上下辊速比、变形率等生产因素与钢板头部弯曲方向和弯曲程度的关系，从而可有效地控制钢板头部弯曲。

Heat transfer ; network analysis ; glass tank furnace ; gas radiation

传热；网络分析；玻璃池窑；气体辐射

Ni0.5Zn0.5Fe2O4 nano-crystalline was prepared by sol-gel self-propagating combustion method, and sintered at 550, 800 and 1050 ℃, respectively. The analysis methods of X-ray diffraction and microwave network analyzer were used to investigate the products after annealing.

中文摘要：采用溶胶-凝胶自燃烧法制备了Ni0.5Zn0.5Fe2O4纳米晶，将其分别在550、800和1050 ℃下二次退火2 h，利用XRD和微波矢量网络分析方法对二次热处理产物及其电磁性质进行了研究。

This paper investigates the interlocking directorates and relative corporate networks by social network analysis.

文章对公司治理的连锁董事问题运用了社会网络分析法进行研究。

An interpretation chart for interpreting reservoir lithology with log parameter is established and a logging suite suitable for the lithologies in the s.

针对舞阳、襄城地区盐湖相地层的特点、勘探情况及测井资料现状，采用数理统计、神经网络分析技术等一些近代数学方法，成功地研制了一套定性、定量识别储层岩性的方法，并建立了储层岩性测井参数解释图版和一套适应该地区岩性的测井系列。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。