用于水电厂设备的故障诊断的贝叶斯网络模型

通过分析水电厂设备故障诊断所面临的不确定性等问题以及当前常用诊断方法存在的局限性,研究基于贝叶斯网络的设备故障诊断方法,提出了适合于诊断问题的贝叶斯网络结构并阐述了基于贝叶斯网络故障诊断的团树推理算法.该方法综合考虑了多故障、故障症兆模糊以及电厂设备操作之间有依赖关系等情况.通过丰满水电仿真系统中水机调速器故障诊断的应用实例,证实了该方法在信息不确定条件下进行诊断决策的有效性和准确性.     

基于Rough Sets-C4.5的故障征兆提取与判别

针对原始信息系统往往存在大量重复样本和冗余属性,从而影响实际故障诊断的精度和速度这一问题,介绍了一种基于粗糙集和决策树C4.5算法相融合的故障诊断模型,用于设备的精确和快速故障诊断.利用粗糙集具有较强的处理不确定和不完备信息的能力,对原始样本集进行离散化及约简处理;同时,利用决策树C4.5算法对约简后的决策表进行快速学习并形成树状故障分类器.以实例介绍了利用该模型进行故障诊断的完整过程.     

Automatic Correcting Control Method of RMG Based on Changeable Transducer Connection Form

By analyzing causes, damages and popular solutions for gnawing rail phenomenon of Rail-Mounted Gantry （shorted for RMG）, this article puts forward a kind of automatic correcting control system, the system can change between two transducer connection forms, and as a result, can prevent or decrease gnawing rail problem to a great extent. We present principles of correcting obliquity, sideward displacement of gantry frame and principles of malfunction diagnosis and some important schematic diagrams. The most significant feature of our system is that we can change transducers＇ connection form to respective or cross driving mode according to the extent of obliquity and sideward displacement of gantry frame, which make full use of both modes＇ advantages. As a result, the system not only can minish gnawing rail phenomenon, diagnose causes of gnawing rail and give an corresponding alarm, but also, in cross connection driving mode, has an unique capacity of preventing gnawing rail phenomenon utilizing its own characteristics under cross connection mode and gantry frame＇s rigidity.     

便携式机械设备现场动态分析系统研究

研究并开发了用于机械设备现场故障诊断的便携式动态分析系统．文中对系统的硬件及软件技术进行了详细的描述．该系统体积小、重量轻、操作简便、诊断与分析功能强，适合于电力、石化、矿山、冶金等工矿企业的机械设备故障诊断及动态分析应用     

灰色 AB_0型关联分析故障诊断方法与模糊诊断方法的比较

提出了AB_0型关联度分析的基本思想,给出了AB_0型关联度的计算公式及其分析过程与步骤,并就其有关的主要概念、基本特点、方法原理、实现过程、适用范围及应用前景等方面与模糊诊断方法进行了分析比较.最后通过实际诊断算例结果的对比,提出了作者自己的观点与体会.     

全状态数字化建模及其在水电机组维护中的应用

为了减少停机时间和维修费用,水电厂正在逐步从计划检修向状态检修过渡。为了满足状态检修的需要,在三维动态建模技术和分布式物理图网建模技术的基础上提出了水电机组全状态数字化建模的概念并分析了其建模基础、建模步骤、关键技术及建模目标。以水轮机调速系统摇摆式主接力器为例详细描述了全状态数字化建模的实现方法及其在水电机组维护域中的应用情况。全状态数字化模型的实现和应用将促进水电设备运行-维护-管理自动化水平的发展和提高。     

中医问诊术语临床英译探讨

中医问诊术语英译是中医临床用语英译的重要部分。文章结合中医临床英译实践,以《中医药学名词》,WHO International Standard Terminologies on Traditional Medicine in the Western Pacific Region和《中医基本名词术语中英对照国际标准》三大中医术语标准收录的中医问诊术语为蓝本,探讨对应性、自然性、通俗性和文化性原则在中医问诊术语英译中的应用。     

Combination Method of Principal Vector Machine for On-line Process Monitoring and Fault Diagnosis

On-line monitoring and fault diagnosis of chemical process is extremely important for operation safety and product quality. Principal component analysis （PCA） has been widely used in multivariate statistical process monitoring for its ability to reduce processes dimensions. PCA and other statistical techniques, however, have difficulties in differentiating faults correctly in complex chemical process. Support vector machine （SVM） is a novel approach based on statistical learning theory, which has emerged for feature identification and classification. In this paper, an integrated method is applied for process monitoring and fault diagnosis, which combines PCA for fault feature extraction and multiple SVMs for identification of different fault sources. This approach is verified and illustrated on the Tennessee Eastman benchmark process as a case study. Results show that the proposed PCA-SVMs method has good diagnosis capability and overall diagnosis correctness rate.     

运用树木活力度进行城市生态环境质量评价初探--以吉林市为例

以往生态环境质量评价中，通常采用单一的环境指标，难以全面综合的反应城市生态环境质量状况，本文提出了“树木活力度”这一新的综合生态指标，并结合实际，对运用这一指标进行城市生态环境质量评价的方法、原理进行了初步探讨。