再制造航空发动机涡轮盘LCF寿命预测研究

针对缺乏航空发动机再制造涡轮盘低周疲劳(low cycle fatigue,LCF)参数数据,无法直接利用传统寿命预测方法进行再制造涡轮盘LCF寿命预测的现状,考虑疲劳极限与疲劳寿命的关系,提出利用再制造涡轮盘寿命修正系数,对通过有限元应力-应变分析及局部应力-应变法得到的寿命预测结果进行修正的方法,实现再制造涡轮盘寿命预测．最后将预测结果与相关试验结果进行对比,证明预测结果具有一定准确性．     

Overview of the Importance of Intelligent Approaches on Machinery Faults Diagnosis and Prediction Based on Prognostic and Health Management/Condition-Based Maintenance

Condition monitoring is increasingly used to anticipate and detect failures of industrial machines.Failures of machines can cause high maintenance or replacement costs.If neglected,it may result in catastrophic accidents leading to production shrinkage.The potential failure would negatively affect the profitability of the company,including production shut down,cost of spare parts,cost of labor,damage of reputation,risk of injury to people and the environment.In recent years,condition-based maintenance( CBM) and prognostic and health management( PHM) are developed and formed a strong connection among science,engineering,computer,reliability,communication,management,etc.Computerized maintenance management systems( CMMS) store a lot of data regarding the fault diagnosis and life prediction of the machinery equipment.It's too necessary to uncover useful knowledge from the huge amount of data.It's vital to find the ways to obtain useful and concise information from these data.This information can be of great influence in the decision making of managers.This article is a review of intelligent approaches in machinery faults diagnosis and prediction based on PHM and CBM.     

梁士诒与“洪宪帝制”

<正> 梁士诒,北洋军阀时期旧交通系的首领,他一生中的主要活动和北洋军阀有着不可分割的联系,袁世凯统治之际,是他政治生涯的鼎盛时期,其标志是:“洪宪帝制”过程中,他扮演了重要角色,起了举足轻重的作用,成为袁氏身边的“大红人”。本文欲就此问题略加论述。 梁士诒,是袁氏智囊团的主要人物之一。《民国野史》中记载:“辛亥革命时期,真     

中国科技术语里经由日语进入汉语的德语外来词汇研究

在中国科技术语里有些术语来自日语,但仔细研究不难发现,这些来自日语的术语其实来自德语,它们都是来自德语的借词。迄今为止,国内学界仅仅在有限的几篇文章里间接、泛泛提到了这一点。文章试就日语中来自德语的外来词的概况、历史、分布范围及其与德语中的词义比较等进行分析,并做了进一步展望。     

Machinery Condition Prediction Based on Support Vector Machine Model with Wavelet Transform

Soft failure of mechanical equipment makes its performance drop gradually,which occupies a large proportion and has certain regularity. The performance can be evaluated and predicted through early state monitoring and data analysis. The vibration signal was modeled from the double row bearing,and wavelet transform and support vector machine model（ WT-SVM model） was constructed and trained for bearing degradation process prediction. Besides Hazen plotting position relationships was applied to describing the degradation trend distribution and a 95%confidence level based on t-distribution was given. The single SVM model and neural network（ NN） approach were also investigated as a comparison. Results indicate that the WT-SVM model outperforms the NN and single SVM models,and is feasible and effective in machinery condition prediction.     

选择不同主体材料改善有机电致红光器件性能

文章讨论了分别利用(4,4,-bis-triphenylsilanyl-biphenyl)BSB;(1,4-bis(triphenyllsily)benzene)UGH2;(1,3-bis(9H-carbazol-9-yl)benzene)MCP三种不同的主体材料制备有机电致红光器件.所用的器件结构为:ITO\Meo-TPD(30 nm)\NPB(20 nm)\MCP:Ir(piq)3(5%:20 nm)\BCP(5 nm)\TPBi(40 nm)\LiF(1 nm)\Al,主体材料为MCP时,主客体之间的LUMO能级之差较小,该组器件的亮度最大,当外加电压达到16 V时,器件的发光亮度为4514cd/m2.当以BSB为主体材料时,主客体之间的的HOMO能级之差ΔH较大,器件的漏电流较小,相应的发光效率较高,当电压为7 V时,器件的最大电流效率为3.30 cd/A.     

浅谈竖炉小水梁冷却工艺改造的技术比较和经济分析

本文以黑龙江建龙钢铁10m2竖炉（球团）小水梁为例,通过对不同循环水冷却工艺流程、特点及其经济效益进行比较,建议竖炉（球团）小水梁部分采用单独软水密闭循环冷却工艺和板式换热设备,这对钢铁厂节水节电,降低运行费用,提高经济效益和节约成本具有重要意义。