粗糙集理论在柴油机故障诊断中的应用

以柴油机故障诊断为背景,研究了基于粗糙集理论的参数优化在故障诊断中的应用.首先采用小波包能量谱方法提取振动信号的特征参数,并用粗糙集理论对其进行属性约简,最后用RBF神经网络对各类故障进行辨识,结果表明:利用粗糙集约简后,通过减少神经网络的输入节点数,简化网络的结构,提高了诊断的准确率及效率.     

TCP SYN端口扫描的研究

根据TCP SYN端口扫描原理,在Windows2000的平台上，用VisualC 6.0开发工具研究TCP SYN端口入侵及其扫描检测的实现。其中，使用了原始套接字（raw socket）编程来发达自己构造的IP数据包和接受网络层的IP数据包。     

Mobilizing Condensate in Gas Reservoirs–A Numerical Simulation Study

Abstract

A mechanism of a commingled Huff 'n Puff cycles of gas cross flow from a highly pressurized lower formation into a depleted upper formation has proven to be effective in reducing gas-well productivity losses due to near-wellbore condensate dropout. Compositional simulation was used to evaluate the performance of gas wells hampered by liquid dropout and to assess ways of producing the gas field. As a result of liquid re-vaporization the study shows that an appropriate scheduling of huff 'n puff shut-in and production cycles lead into a decline of in-situ liquid dropout and an increase in surface liquid recovery.     

GRAYLOC法兰拆装技术

GRAYLOC(高压自紧)连接件作为一种特殊的法兰密封形式凭借其本身尺寸小、质量轻、强度高、韧性好、拆装便捷,尤其是其独特的金属密封使其在安全性能上远远优于其他法兰产品,已广泛应用于煤化工、核工业、航空、海洋等生产、制造行业。文章结合神华鄂尔多斯煤制油分公司煤液化装置GRAYLOC高压密封连接件拆装实践,介绍了此种密封连接件的拆装技术,阐述了这类连接件在拆装过程中的技术要点及注意事项。     

The relationship of early alliance ruptures and their resolution to process and outcome in three time-limited psychotherapies for personality disorders.

This study examined the relationship of early alliance ruptures and their resolution to process and outcome in a sample of 128 patients randomly assigned to 1 of 3 time-limited psychotherapies for personality disorders: cognitive–behavioral therapy, brief relational therapy, or short-term dynamic psychotherapy. Rupture intensity and resolution were assessed by patient- and therapist-report after each of the first 6 sessions. Results indicated that lower rupture intensity and higher rupture resolution were associated with better ratings of the alliance and session quality. Lower rupture intensity also predicted good outcome on measures of interpersonal functioning, while higher rupture resolution predicted better retention. Patients reported fewer ruptures than did therapists. In addition, fewer ruptures were reported in cognitive–behavioral therapy than in the other treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ARP漏洞及其防范技术

本文介绍了ARP协议,并讨论ARP协议所存在的安全隐患,进而分析了利用ARP欺骗实现交换式网络数据包的嗅探与监听原理,最后提出了相应的防范措施。     

基于振动信号小波包提取和短时能量分析的高压断路器合闸同期性的研究

该文提出了一种分析高压断路器合闸同期性的新方法将小波包提取算法和短时能量分析方法相结合，利用小波包分解与重构原理将断路器合闸振动信号分解到不同频段中，并对代表高频冲击信号的分解系数进行重构，然后运用短时能量分析方法对重构后的信号进行分析，辨识出合闸变位点。通过对三相合闸过程的分析，得出三相同期性。通过MATLAB仿真分析和实验结果验证了该方法的有效性。     

基于1394b总线高效率通信的研究

随着通信技术的快速发展,各领域对高速总线的要求越来越高.在整个通信网络中,1394b的高效率有着至关重要的作用.对整个1394b总线网络提出了准确性、实时性和可靠性等约束,保证了1394b总线的传输特性;对1394b总线网络中传输的异步流数据包和STOF数据包进行包格式设计,确保了1394b总线网络传输的准确性;搭建了一个单总线四节点的1394b总线网络作为测试验证平台,并对该总线通信进行了测试与验证.经过测试分析和测试总结,本通信机制下整个通信网络的高效性能都达了到预期目标.     

对几个小波基本概念的理解

讨论实际应用中经常涉及但容易产生误解的小波基本概念,以期提高电力系统小波应用研究水平。这些小波基本概念是:容许性条件;二进离散与二进小波;连续小波的离散条件;小波基;A=B=1的紧框架与正交小波;小波滤波器长度与时域分辨率;小波的滤波特性与不同尺度小波的频带交叠;线性相位小波与信号完全重构;双正交小波的小波包及小波包分解与1/2频程分解;整数倍伸缩小波变换与分数倍伸缩小波变换;小波的正则度与消失矩;Motlet函数与Morlet小波;小波变换模极大值(定义、与突变点位置的关系、与Lipschitz指数的关系、对小波的要求);时域、频域同时紧支小波;(时域)紧支正交线性相位小波;表征小波特性的基本指标与有价值的新小波。     

小波包分析在滚动轴承故障诊断中的应用

结合小波包分析和能量谱分析方法 ,提出一种新的滚动轴承故障诊断方法。利用小波包对滚动轴承振动加速度信号进行分解 ,求出各频率段的能量 ,并以此作为滚动轴承发生故障的特征量对振动信号进行重构 ,比较正常信号和故障信号的差异 ,从而识别滚动轴承的故障。通过对于实测信号的分析证明该方法具有特征参量少、故障特征突出等优点 ,可有效地用于滚动轴承的故障诊断。