SSI:一种IPv6/IPv4多址同源识别模型

IPv6/IPv4共存环境下多址同源识别是共存网络管理与拓扑发现的一个关键问题。现有研究主要集中于子网内部的双栈发现及单一IP协议栈中的别名解析,难以识别远程IPv6/IPv4共存网络中的多址同源。通过分析同源地址间的本质联系,提出一种IPv6/IPv4多址同源识别模型(SSI),该模型综合利用特殊地址格式匹配、TCP时钟指纹比对和上层协议短时致瘫等多种方式来提高同源地址的识别能力。实验结果表明,上述方法均可有效识别IPv6/IPv4多址同源;SSI模型具有较理想的识别率和正确率。     

Ozone-Based Advanced Oxidation Processes for the Decomposition of N-Methyl-2-Pyrolidone in Aqueous Medium

The present study investigates the decomposition of N-Methyl-2-Pyrolidone (NMP) using conventional ozonation (O₃), ozonation in the presence of UV light (UV/O₃), hydrogen peroxide (O₃/H₂O₂), and UV/H₂O₂ processes under various experimental conditions. The influence of solution pH, ozone gas flow dosage, and H₂O₂ dosage on the degradation of NMP was studied. All ozone-based advanced oxidation processes (AOPs) were efficient in alkaline medium, whereas the UV/H₂O₂ process was efficient in acidic medium. Increasing ozone gas flow dosage would accelerate the degradation of NMP up to certain level beyond which no positive effect was observed in ozonation as well as UV light enhanced ozonation processes. Hydrogen peroxide dosage strongly influenced the degradation of NMP and a hydrogen peroxide dosage of 0.75 g/L and 0.5 g/L was found to be the optimum dosage in UV/H₂O₂ and O₃/H₂O₂ processes, respectively. The UV/O₃ process was most efficient in TOC removal. Overall it can be concluded that ozonation and ozone-based AOPs are promising processes for an efficient removal of NMP in wastewater.     

电子商务模式的多维分类体系研究

电子商务模式的开展是实现电子商务应用的重要问题之一.为充分探讨电子商务模式的体系建立,在总结已有成果基础上,本文基于电子商务模式的分类讨论十大类基本的电子商务模式,分析构建多维电子商务模式分类体系.     

The Chemistry of Water Treatment Processes Involving Ozone,Hydrogen Peroxide and Ultraviolet Radiation

Advanced oxidation processes are defined as those which involve the generation of hydroxyl radicals in sufficient quantity to affect water purification. The theoretical and (practical yield of OH from O₃ at high pH, 0₃/H₂0₂, O₃/UV and H₂O₂/UV systems is reviewed. New data is presented which illustrates the importance of direct photolysis in the O₃/UV process, the effect of the H₂0₂:0₃ ratio in the O₃/H₂O₂ process, and the impact of the low extinction coefficient of H₂O₂ in the H₂0₂/UV process.     

基于IPv6的网络入侵检测技术研究

IPv6技术是下一代互联网的核心技术。通过分析现有网络安全系统的基本原理,针对IPv6网络的特点,提出在IPv6环境下采用基于协议分析和模式匹配技术相结合的入侵检测系统架构。采用该系统架构能够更快、更有效地处理信息数据帧和连接,同时能够判断一个通信的实际内容及具体含义,具有抗躲避性强、系统资源占用小、检测速度高、误报率低的特点。     

警用移动信息系统安全解决方案

当前,在社会矛盾复杂化、警务工作效率必须不断提高的大背景下,我国各地方公安机关陆续将警用移动信息系统纳入信息化建设的重要指标。为了向公安各部门一线民警提供快捷、方便的实现信息共享渠道,就必须在现有的公安信息系统的基础上,发展出可移动的信息处理系统。由于各地公安机关都是各自开发所需的相关业务的专项警务信息系统,容易在安全设计上存在只注重功能轻视安全问题的错误,警务人员在使用这些系统提高工作效率时存在公安警务工作泄密、公安资料不安全等问题。因此,在以现代无线通讯技术和互联网技术相结合产生的移动互联网技术的飞速发展中,为警用移动信息系统提出安全解决方案提供了必要的技术基础。在分析警用移动信息系统网络架构、安全需求及建设现状的基础上,本文设计并实现了以移动3G技术为基础的Socket方式访问的警用移动信息系统。     

八面河油田近年注水开发工作的实践与认识

八面河油田油藏类型多样,开发方式多样,其中注水开发储量占全油田动用储量的61%。近年来,为改善注水开发油藏开采效果,保持产量稳定,油田针对各区块注水开发中存在的问题,在面4区面5块、广北8块、面14区沙三上采取了完善注采井网,注水井注氮调剖,水井动态调水以及改善水质等方面的工作,初步取得了较好的效果。     

底部局部辐射加热窑炉内温度场数值模拟

提出了底部局部辐射加窑炉内温度场数值分析的控制方程组，分别对平面加热及半圆柱形加热面两种算例进行了数值计算，得了影响烤花烤窑炉内温度场均匀性的主要因素和有加热面发射率，加热面形状，加热面相对位置及窑炉墙体热阻和墙体与外界的换热热阻。     

Location of steel reinforcement in concrete using ground penetrating radar and neural networks

Ground-penetrating radar is becoming increasingly popular for use as a non-destructive assessment method for investigating reinforced concrete structures. The amount of data collected however can be very large and take a significant level of subjective experience to interpret. This study focuses upon the use of a neural network approach to automate and facilitate the post-processing of ground penetrating radar results. The radar data is reduced to a simplified data set by using an edge detection routine. Signal reflections from reinforcing bars displaying a hyperbolic image format are detected using a multi-layer perceptron (MLP) network with a single hidden layer containing 8 nodes to recognise a simplified hyperbolic shape. Training and testing of the network was carried out making use of an emulsion analogue tank, simulating the properties of concrete, and using real concrete specimens. The results showed that the use of a MLP neural network approach could be quite effective in automating the identification and location of embedded steel reinforcing bars from a radar investigation. Accurate estimation of depth, or cover, requires a reliable knowledge of the dielectric properties of the concrete, and recent work using a specially-developed wideband horn antenna for direct determination of in situ properties is also outlined.     

用于树脂砂造型的木模结构设计及制作工艺

从木模起模和木模强度等方面入手，阐述了树脂砂木模结构的设计、木模结构简化的方法。提出了木模的选材及制作工艺