网络对大学生的影响及对策

自20世纪互联网诞生以来,网络这把"双刃剑"对大学生的教育带来了许多正面和负面的影响,如何利用好互联网,加强校园网特别是宿舍局域网的管理,进行网络规范化教育,是高校学生工作所面临的新课题.     

京沪高铁馈线重合闸成功后的异常情况分析

牵引供电系统是由牵引变电所亭和接触网线路组成,其中接触网线路是机车或列车取得电能的唯一途径,但它易受外界环境的影响,比如说雷击、污秽、异物和腐蚀等外部因素都有可能造成牵引供电系统接地或者短路故障,从而引发牵引变电所亭跳闸。为了缩短故障延时和防止故障灾害扩大,牵引变电所亭装设有各类微机保护装置,以满足速动性、灵敏性、可靠性和选择性的要求。京沪高铁全线供电方式大多采用全并联AT供电模式,因此单独一条供电臂上分别包含有牵引变电所、AT所和分区所,它们之间的微机保护配合对于系统的安全稳定有着极其重要的意义。本文将对北京局管段内的京沪高铁的几起保护配合异常事件进行归纳、总结和分析,并给出相应的整定值修改建议。     

政治学视野中的社会主义和谐社会分析

当前,构建"社会主义和谐社会"已成为中国社会的共识.在政治学语境下,从社会主义和谐社会的政治属性、政治价值、政治意识形态和政治合理性四个方面进行探索,有助于加深对社会主义和谐社会的认知,具有重要的现实意义.     

Relationship between alanine aminotransferase levels and metabolic syndrome in nonalcoholic fatty liver disease

Objective:To investigate the relationship between alanine aminotransferase (ALT)levels and metabolic syndrome (MS)in nonalcoholic fatty liver disease(NAFLD).Methods:A total of 26527 subjects who received medical health checkup in our hospital from January 2005 to July 2007 were enrolled in the study.The diagnosis of fatty liver was based on ultrasound imaging.MS Was defined according to the criteria of the Adult Treatment Panel Ⅲ.ALT,triglyceride(TG),high density lipoprotein cholesterol(HDL-c),fasting plasma glucose(FPG),height,weight,waist circumference(WC),systolic blood pressure (SBP)and diastolic blood pressure(DBP)were measured in each subject to analyze the relationship between MS and ALT activity.Results:(1)The prevalence of NAFLD in men(30.94%)was significantly higher than that in women(15.65%);(2)The incidence of MS in NAFLD(33.83%)was significantly greater than that in non-NAFLD(10.62%);(3)Of the 6470 subjects with NAFLD,in the age-adjusted partial correlation analysis,there were statistically significant correlations between the ALT levels and most metabolic risk factors in each sex(P＜0.01),except that ALT levels had no correlation with HDL-c in women.Moreover,in the multiple stepwise regression analysis,SBP lost its significance,and WC,body mass index(BMI),age,DBP,TG and FPG were independently associated with ALT levels in both sexes (P＜0.05).HDL-c remained significant and was independently related to ALT leveis in men;(4)ALT levels were significantly higher in subjects with MS compared to those without MS(P＜0.001).Mean ALT levels increased with the number of MS cornponents in each sex (P.＜0.05 for trend).Conelusion:We found a strong relationship between ALT leveIs and MS in NAFLD and revealed that the cluster of MS components might be the predictor for ALT elevations.     

效度在语言测试中的重要性

讨论了效度在四种测试中的重要作用，以及各种效度之间的关系，说明要想达到测试的目的，设计试卷一定要把握好效度这个标准。     

用建构观点学习数学初探

建构理论可以解释很多复杂的数学概念，并对学习这些概念提出了建设性的方法。建构理论可以帮助我们学习一些教学策略，从而引导学生学习复杂、抽象的数学概念，并应用这些概念去证明定理、举例说明和解决问题。     

光自差CO2相干激光雷达光学头设计与测试

对光自差阵列探测CO2激光相干雷达进行了研究，通过对大量红外光学系统的分析，提出了一种适用于光自差阵列探测激光相干成像的光学头系统，并对该光学头系统进行了设计和实验性能测试，该光学头系统可实现光束的一维扩展，其纵横向扩展比为1：32。     

论课程改革与教师发展

新课程的全面实施是对教师的教育观念、教学方式、教学行为的改变提出了全新的要求,而实现课程改革目标的关键在于教师的素质和能力主动地适应新要求,促使教师的教育观念、教学方式及教育行为的全面转变。     

啤酒工业废水处理工艺方案浅析

介绍了啤酒废水的来源、减污措施及处理工艺的原理,通过工艺流程、主要设计参数等方面,综合比较接触氧化法、SBR工艺、氧化沟工艺和厌氧生物处理几种常用工艺,在此基础上提出采用厌氧-好氧联合工艺处理啤酒废水。     

EPS电源正弦脉宽调制逆变器的设计

介绍了EPS（Emergeney Power Supply）正弦波逆变器的工作原理，重点讨论利用SG3524、ICL8038产生SPWM波的方法，设计了逆变器的控制及保护电路，制作了1KW、50Hz实验样机，给出实验样机输出波形。