浅析路堤填料含水率与K30测试值的关系

介绍路基填筑时K_(30)测试值与填料含水率的关系及操作注意事项     

E_(vd)路基压实标准在铁路规范中的规定与特点

介绍国外动态变形模量Evd路基压实标准的发展与现状 ,以及我国对Evd从研究、应用 ,到纳规的发展过程 ;阐述Evd标准在高速铁路客运专线、新建铁路以及既有线提速改造中的应用特点与前景     

秦沈客运专线东部填料改良试验研究

通过对秦沈客运专线东部的细砂等粗粒土填筑路基不满足压实要求的机理分析，提出了满足秦沉客运专线路堤基床以下部位压实要求的细砂等粗粒土填料判别标准和物理改良设计方法，并应用于实际施工中。     

基于M/G/K排队模型的北京地区高速公路收费站通行能力研究

在分析高速公路收费交通流行运行特征的基础上，采用较符合实际的M／G／K排队模型，利用北京地区高速公路收费站的实测数据，推算出实行计算机辅助收费的各种收费制式收费站通行力指标。     

X1K型集装箱专用平车增载改造

简要介绍了X1K型集装箱专用平车改造方案、生产工艺及其改造后的主要特点.     

Caspase-3和Bcl-2在白血病细胞株凋亡过程中的表达及其与多药耐药的关系

目的研究Caspase-3在阿霉素(ADR)诱导的K562和K562/AO2细胞株凋亡过程中对Bcl-2蛋白表达的调控,探讨两者相互作用在白血病多药耐药中的分子机制。方法原位细胞凋亡检测法观察凋亡细胞的形态学改变;流式细胞仪测定凋亡率及Bcl-2蛋白的表达;酶显色活性分析法测定Caspase-3的活性。结果①K562细胞株的凋亡率对ADR呈时间、剂量依赖关系,K562/AO2细胞株则无此依赖关系。②未加Caspase-3抑制剂的K562细胞株Bcl-2阳性表达率和Caspase-3活性对ADR呈时间、剂量依赖关系;加入抑制剂的则无此关系,但作用48 h后Bcl-2阳性表达率下降,Caspase-3活性上升。无论加入Caspase-3抑制剂与否,K562/AO2细胞株的Caspase-3活性和Bcl-2阳性表达率均无变化。结论Caspase-3的变化能引起Bcl-2蛋白表达水平的变化,二者与凋亡关系密切,并在多药耐药中发挥重要作用。     

IMAGE ANALYSIS BASED ON EDGE DETECTION TECHNIQUES

IntroductionEdges are pixels where brightness changesabruptly and often used in image analysis for find-ing region boundaries.It locates sharp changes inthe intensity function.Edges detection is basic im-age features.They carry useful information aboutobject boundaries.Edges can be used for object i-dentification,image analysis and image filteringapplications as well.We shall consider as an edgethe border between two homogeneous image re-gions having different illumination.This definitionimp…     

Travel time statistical modeling with the Halphen distribution family

ABSTRACT

This article introduces the Halphen distribution family for modeling travel time distributions and their reliability on single road links. This probability family originally used in hydrology has a set of relevant characteristics. It is composed of three probability distribution functions for which the mathematical properties are described here. The article uses a graphical representation, the δ-Moment Ratio Diagram (δ-MRD). This tool allows characterizing travel time reliability as well as selecting best distribution candidates within the fitting processes, by considering empirical data sets. A systematic methodology is developed to take advantage of both aspects. From maximum log-likelihood estimation, it is shown that Halphen distributions are among the best state-of-the-art solutions for the travel time modeling purpose. This global framework is validated using two empirical data sets: an urban data set gathered in Portland, Oregon (USA), and a periurban data set from Lyon (France). The model calibration is eased through the use of the δ-MRD; this property opens new research directions about the mapping between traffic states and statistical modeling. It comes from all these considerations that the Halphen family is suitable to describe accurately the travel time dynamics on single links. Therefore, it could be part of a decision support system for practitioners interested in travel time variability.     

复励牵引电动机控制的几个问题

复励牵引电动机便于实现无级磁场削弱,控制简单,并可减少晶闸管元件数量。但复励牵引电动机在控制上也带来一些新问题:如需要预励磁;为使并联牵引电动机间的负荷分配均匀,需要采取特别措施;牵引时串励和他励的调节方式,以避免产生振荡;制动力的控制方式及在低、中速区实现较大制动力的问题。本文就这些问题提出了解决的途径。     

南京地区P-5L2型数字粉尘仪换算系数K值的测定

为确定南京地区P-5L2型数字粉尘仪的换算系数K值,用北京新技术应用研究所生产的P-5L2型数字粉尘仪和江苏省建湖电子仪器仪表厂生产的HFC-3BT呼吸性粉尘采样器,对南京石榴园采石厂和浦镇车辆厂的各种粉尘进行了测定,得出了不同作业点不同粉尘的总尘和呼吸性粉尘质量浓度与粉尘相对质量浓度的换算系数K值。