网络技术

The main objective of this dissertation was to develop methodologies with capability of engineering application for simulating flow in fractured rock using discontinuum models. The study work includes three parts. In the first part, numerical methodology of three-dimensional discrete fracture network model casing on hybrid BEM-channel was presented, and the technique for improve the model's computing efficiency was also studied. Firstly in this part, computer simulation methodology based on the Baechermodel for generating network of discrete fractures was presented, which includes the follow details: probability distributions of fracture density,orientation, trace length, size, and aperture and estimation of their statistical parameters; stochastic models of fracture network; Monte-Carlo's simulation method; numerical simulation procedure and technicality.

给出了离散裂隙网络模型所依据的基本假定；发展了基于Baecher模型的离散裂隙网络计算机随机生成技术：详细地推导了单裂隙渗流和多裂隙相交网络渗流的边界单元法公式，发展了离散裂隙网络中稳态渗流的边界元数值技术，并且讨论了相关的具体数值技术细节，如角点的处理方法，单元的自动剖分等：描述了混合边界元—管流模拟方法及其数值实现；研究了裂隙网络的简化方法，并针对裂隙网络边界元法的特点提出了一种改进的分块三角分解法。

At first, with the low-frequency data measured, three of the LRE fault detection systems for the real-time condition are proposed using the nonlinear identification technology of the BP neural network, the state estimation technology of the dynamic neural network, and the pattern recognition technology of the fuzzy hypersphere neural network. The learning algorithms of the BP and dynamic neural network are researched at the same time. Furthermore, while the engine operation is divided into the start and steady-state processes, the real time ability, the response time, the accuracy, the robustness, the sensitivity and the monitoring parameter optimization are studied. In the test data analyses of the YF-75 engine, the detection system correctly carried out for all normal tests, and in the three abnormal tests the engine faults were accurately forecasted.

首先，基于低频测量数据，采用BP神经网络的非线性辨识技术、动态神经网络的状态估计技术及模糊超球神经网络的模式识别技术，提出了三种发动机故障实时检测系统；同时研究了BP神经网络和动态神经网络的学习算法；另外还把发动机工作分为启动过程和稳态过程，分别讨论了神经网络故障检测系统的实时性、及时性、准确性、鲁棒性、敏感性及参数优化问题；在YF-75发动机试车数据分析中，不仅全部正确地监测了正常试车过程，而且准确地预报了三次异常试车中的发动机故障。

Based on investigating the short and intermittent structural plane, surrounding rockmass of the huge underground powerhouse in Three Gorge has been divided into five statistical similar areas according to its characteristic of rockmass structure by applying structure plane network simulation. Distributed characteristic of structural plane has been studied and based on it mechanics macrocharacteristic has been studied:(1) It is the first time that based on the result of structural plane network simulation rockmass quality of every structure area has been studied with applying blurred information optimum seeking technique and be compared with and RQD method. The result indicated that it has better effect to evaluate rock quality with blurred information optimum seeking technique.(2) It is the first time that the interrelated relationship of the result of in-suit rockmass deformation test and fractal characteristic of structure on test point has been applied to determine rockmass deformation parameter. The question of evaluating deformation parameters of engineering rockmass has been solved.(3) Anisotropy strength parameters have been determined by applying shear zones simulating method. The result indicated that there are different strength parameters in every structural area, after comparing the result of Fast Lagranian Analysis in continua number simulation method with that of method of weighted mean according to continuity. The result indicated that when a suitable reduction coefficient is been considered rockmass strength parameters can be simply and fast determined with method of weighted mean according to continuity where there is not enough test result.(4) Damage characteristic has been studied based on analysis fractal characteristic of structural plane network by applying fractal-damage coupling method. It is the first time that the concept of damage degree has been set up to evaluate rockmass quality according to the biggest principal damage.

通过对短小、断续性结构面统计特征的研究，将地下厂房区划分为五个岩体结构统计均质区，应用结构面网络模拟技术研究了各个岩体结构均质区结构面的发育分布特征，并以此为基础对岩体宏观力学特性进行了深入研究：(1)首次通过在结构面网络模拟计算结果的基础上，应用模糊信息优化技术研究了厂房区各个岩体结构分区的岩体质量并与岩体基本质量指标研究法、岩体质量指标RQD值研究法作了对比，结果表明以结构面网络模拟结果为基础，应用模糊信息优化技术进行岩体质量评价能够取得很好的效果，解决了工程岩体质量的定量评价问题；(2)首次通过对已有的现场大型岩体变形试验结果的分析及相应试验点岩体结构分形特征的研究，建立了结构面分布的分形维数和岩体变形指标间的相关关系，并首次应用这种相关关系根据结构面网络模拟及分形维数计算结果确定了缺少试验结果的地下厂房各工程部位的岩体变形指标而且应用于围岩稳定性计算，解决了工程岩体宏观变形参数的评价问题；(3)应用在结构面模拟网络图上模拟岩体剪切破坏带的方法，得出了岩体在不同方向上的强度参数，结果表明岩体的强度特性与结构面的发育方向和程度有着明显的关系，各个岩体结构均质区具有不同的强度参数；同时还通过应用拉格朗日差分法对岩体强度指标的数值分析并与按连通率加权平均计算法对比表明，按连通率加权平均计算法在考虑合理的折减系数情况下，可以简单快速地对缺少现场大型试验结果的具体工程部位实现岩体强度指标的估计，通过以上研究解决了工程岩体抗剪强度参数的评价问题；(4)通过结构面网络分形维数的研究，应用分形损伤耦合分析方法，研究了厂房区岩体的损伤特征，并首次引入"损伤度"的概念，建立了应用最大主损伤评价岩体质量的指标体系。

One:theplanproposes to research and develop the next generation network system structure and related network protocol, with the focus on promoting the multi-media service network technology based on the core of IMS, including IPv6, as well as the research, development, and industrialization of high performance multi-service bearing network technology and end-to-end network QoS and security technology; the goal is to preliminarily understand the next generation network system structure as well as core network QoS and safety in order to form a group of next generation core technology and innovative products that has independent intellectual property to become an important player in the next generation network's international standard.

一、规划提出进行下一代网络体系架构和相关网络协议的研究开发，重点推进包括IPv6、以IMS为核心的多媒体业务网技术、高性能多业务承载网技术和端到端网络QoS保障技术等领域的研发和产业化工作，初步解决下一代网络的体系架构及核心网QoS与安全保障问题，形成一批具有自主知识产权的下一代网络核心技术和创新产品，在下一代网国际标准中占据重要地位。

Computer network management technology ,the relationship between WEB,CORBA,XML and network management are also discussed in this paper. By integrating the benefits of these technologies,we bring forward the network management framework based on WEB/CORBA/Java. This architecture is of excellent characters,such as high expansibility,high retractility,standard interface,multi-planform sustainability.

接着又对计算机网络管理实现技术进行了分析，探讨了当前发展中的新技术——WEB技术、CORBA技术与XML等技术与网络管理的关系，从而提出了基于WEB／CORBA/Java的网络管理框架，该框架具有可扩展性强、高可伸缩性、界面统一、支持多种平台环境等特点。

In chapter 4, basing theories and methods of scientific visualization, and artificial neural network BP algorithm, we integrate the Visual C++, OpenGL graphics library and Excel VBA technique to develop the program of artificial neural network and to make the BP algorithm visually, this program works can be divided into four parts: Using C language to develop program about BP algorithm; Using Visual C++, develop the GUI Interface, make input parameter visually; Using OpenGL graphic technique to display the training sample point in three dimension; at last using Excel DDE technique display the error graphic tables in Excel system In chapter 5, on the view of engineering application, we establish new method of surface reconstruction basing artificial neural network, develop interface program between module and commercial CAD/CAM system, meantime deeply discuss some key problems, for example, setting up the base plane, using the API technique, cutting and editing surface boundary, and also discuss the more compliant problem: how to intersect surface, at end we finish the work of translation from our surface reconstruction module to commercial CAD/CAM system, then make reverse engineering system basing artificial neural network more useful.

第四章基于科学计算可视化理论，依据人工神经网络BP算法理论模型，综合Visual C++，OpenGL图形库以及Excel VBA等多项软件开发技术，编制了人工神经网络程序，实现了BP算法的可视化映射。具体工作分为四部分：利用C语言实现人工神经网络BP算法；利用VisualC++的GUI技术开发图形用户界面，实现参数设置可视化；利用OpenGL图形技术进行三维映射，显示学习样本及训练样本点；利用微软电子表格DDE动态数据交换技术，在Excel上动态显示学习误差曲线图。第五章从工程应用的角度出发，提出了一种新的基于人工神经网络算法的曲面裁剪重构方法，完成了曲面重建模块与通用CAD/CAM系统的接口设计工作，对其中的若干关键问题进行了深入讨论，例如基平面设定、API技术的应用、边界裁剪等问题，同时，对曲面计算中较为困难的曲面相交问题也进行的专门探讨，最终完成了曲面重建模块向CAD/CAM系统的数据传输工作，使人工神经网络逆向工程系统趋向实用。

The breakthrough and the shortcoming of the classified search engine as well as the characteristics and the unacceptability of the network search tools based on traditional classification are discussed.

三。在网络信息资源分类组织的应用技术方面提出了一些新见解，即改进基于分类法的网络检索工具的技术要求、运用现代分类技术促进网络检索工具进一步完善、超文本技术在网络信息资源分类组织中的合理应用以及密切关注其它信息组织技术的研究进展。

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 order to get useful data, it researches the network sniffing technology based on Raw Socket and mainly studies the technology of protocol analyze and data recombine. And it introduces the Trojan horse technique to the network data collection part, improves the process hiding technique, uses the triple-thread technique, and so on. It ensures the imperceptibility and stability of the network data collection part. Then this paper develops pseudo hypertext transfer protocol based on HTTP. This protocol is used in the communication between the network data collection part and the service part, which make the communication more covert.

研究基于Raw Socket的网络监听技术，为了能取到敏感数据，还对协议解析和数据重组技术做了详细研究；并在网络数据采集端引入了木马技术，对进程隐藏技术做了改进，采用三线程技术等，来保证网络数据采集端的隐蔽性和稳定性；接下来本文在分析HTTP协议的基础上设计开发了PHTTP协议，该协议用于网络数据采集端与服务端之间的数据通信，使通信更加隐蔽。

We organize the self-security mechanism of Windows2000 Server, the technology of firewall and network anti-virus system together. We describe the basic theory of the system and provide concrete strategy of the implementation.

通过研究密码技术和防火墙技术等网络安全关键技术，本文给出了青岛检验检疫局网络安全解决方案，将Windows2000 Server自身安全机制、网络防火墙技术和网络病毒防范技术有机结合，对该系统的理论基础进行描述，并对系统的实现做了详细说明。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。