PFI发动机起动阶段THC、NOx的排放控制研究

本文详细阐述PFI发动机THC、NOx的排放起动过程中的控制研究,包括对不同的过量空气系数(空燃比)、点火角的控制验证效果,并对国Ⅵ车型配PFI发动机的排放控制提出建议。     

高寒站区检车调车养路人员冻伤发生情况的调查

冻伤是寒区冬季常见病,铁路系统检车、调车、养路等露天作业工种尤为多见。因此,冻伤的防治成为寒区劳动卫生工作的一项重要研究课题。为了解我局高寒站区检车员、调车员、养路工的冻伤发病率,摸清冻伤发生的规律及其与气温等因素的关系,为冻伤的防治工作提供可靠依据,我们于1983年12月～1984年3月对塔河、林海、劲涛三个地区(以下简称塔、林、劲)的上述工种做了跟班调查,并对所有现职职工进行了冻伤史询问,现将调查结果报道如下。     

矿渣烘干机静电除尘器效果评价

一、设备情况昂昂溪铁路水泥厂使用一台直径1.5m、长8m的矿渣烘干机。物料烘干时产生的大量烟尘经排姻管道排入大气,不但严重污染周围环境,还损失了大量物料。为解决这一问题,该厂安装了一套高压静电除尘器,现已正式投入使用。该除尘系统由变压器、电源控制器、风机、除尘器四个部分组成。采用北京冶金安全仪器厂产CK120/20高压硅整流除尘变压器及同型号电源控     

一种新型排水结构的排水性能试验研究

目前边坡和支挡工程中最常用的排水结构(PVC排水管)服役一定年限后,易发生堵塞,排水功能失效。为研究一种排水效率高、不易堵塞的新型排水结构(排水钉),在室内开展了历时4个月的PVC排水管和排水钉的排水对比试验,系统研究两者的排水性能和抗淤堵性能;同时开展排水钉设置间距和设置长度对自身排水性能的影响试验,并分析排水钉的反滤机制。结果表明:排水钉能持续保持良好的排水性能,而PVC排水管排水性能则逐渐下降,包裹PVC排水管的土工布发生了一定程度的淤堵,使流速最大降幅达35%;砂土中排水钉的有效排水半径约为1.0 m,排水钉置入边坡应穿过最危险滑动面至少1.5 m;排水钉周围形成天然的反滤层,能发挥排水、挡土和防淤堵的作用。     

克令吊起升系统典型液压故障分析

文章以设备说明书和技术通函为理论依据,结合笔者多年的克令吊实际管理经验,以IHI H300160-300型克令吊为例,介绍了船用克令吊起升(俗称钩头)系统的典型液压故障,给出了分析处理液压问题的处理思路,总结出了非常实用的液压故障排查方法和经验。     

Comparison between North-South Aid and South-South Cooperation: Based on the analysis of the new development finance institutions

According to the different players, development cooperation is often divided into North-South Aid and South-South Cooperation, both of which have a history of several decades. Since the beginning of the 21st century, the rise of a number of emerging economies has brought South-South Cooperation into a new stage, which can be seen from the establishment of some new development finance institutions led by developing countries. BRICS Bank, Asia Infrastructure Investment Bank (AIIB) and Silk Road Fund are three important new development finance institutions. Compared with the traditional development finance institutions like World Bank and International Monetary Fund (IMF), they have their own concepts of development cooperation, which are different from the traditional ones. First, the new finance institutions pay more attention to the equality between partners, not imposing conditions and respecting the ownership of development partners. Second, the new development finance institutions value the market philosophy, which means that they emphasize the importance of field investigation and implement development cooperation in accordance with the actual needs of the partners and the comparative advantages of the providers. Finally, the new development finance institutions focus their resources on problem-solving and avoid doctrines-imposing. They believe that it is easier for the developing countries to achieve development through a gradual and bottom-up model. Although there are differences between the traditional and new development finance institutions, the latter is not parallel to or substitute of the former. They can cooperate with each other and provide better public goods for international cooperation through inclusive competition.     

Efficient Dynamic Threshold Group Signature Scheme Based on Elliptic Curve Cryptosystem

The short secret key characteristic of elliptic curve cryptosystem （ECC） are integrated with the （ t, n ） threshold method to create a practical threshold group signature scheme characterized by simultaneous signing. The scheme not only meets the requirements of anonymity and traceability of group signature but also can withstand Tseng and Wang＇s conspiracy attack. It allows the group manager to add new members and delete old members according to actual application, while the system parameters have a little change. Cryptanalysis result shows that the scheme is efficient and secure.     

城市轨道交通建设工程声像档案归档业务探索

从服务于工程建设档案、适应新时代工程档案管理需要出发,成都市城市建设与自然资源档案馆组织相关专业力量,编写了成都市城市轨道交通建设工程全部子项的声像档案制作与归档要求。本文重点介绍了城市轨道交通建设工程声像档案归档类别及范围,供探讨思考,以促进建设工程声像档案接收范围的拓展和服务的提升。     

为全路劳动安全卫生与环保事业作出突出贡献的二十年──祝贺《铁道劳动安全卫生与环保》杂志创刊二十周年

为全路劳动安全卫生与环保事业作出突出贡献的二十年──祝贺《铁道劳动安全卫生与环保》杂志创刊二十周年铁道部第一工程局中心卫生防疫站谭洪铁道部第四工程局中心卫生防疫站乐尚侃北京铁路局中心卫生防疫站李理哈尔滨铁路局齐齐哈尔中心卫生防疫站崔振国沈阳铁路局吉林...