基于Matlab的BP神经网络在公交车辆调度中的应用

根据公交站点客流集散量,选用合适的BP神经网络构建公交车辆调度形式的神经网络预报模型.运用BP神经网络Matlab工具箱设计的基本方法与过程,将BP网络模型引入公交车辆的调度方案研究,计算结果表明,BP模型应用于公交车辆调度形式预测中具有较高的预测精度和良好的泛化能力.     

基于VAR模型的南京市交通量与经济发展关系研究

在对南京市交通量与经济发展指标统计分析的基础上,运用向量自回归模型——VAR模型进行分析,通过采用协整检验模型、Granger因果关系检验模型和脉冲响应函数等分析,得到交通运输与经济发展之间的关系,并给出相应的建议.     

BROMMA吊具接近开关支座的改进

我公司目前有10余台岸桥在用BROMMA吊具。在装卸作业过程中,吊具与箱接触,所受冲击很大,且冲击频率很高,加上作业人员追求速度等因素的影响,吊具损伤尤其是20／40英尺伸缩动作故障的问题突出。在吊具各种受冲击的零部件中,接近开关是最薄弱的。这种重要的电子元件通常由塑料的夹具固定在与吊具体刚性连接的支架上,在冲击和震荡发生时,接近开关往往会改变调定的距离,导致故障的发生。     

复杂环境超小间距隧道盾构掘进施工技术北大核心CSCD

针对浅埋超小间距隧道盾构施工,文章以特拉维夫红线轻轨工程西标段双线盾构施工为工程背景,从隧道加固施工、盾构掘进控制、监测控制与应急管理等方面进行系统研究。结果表明,加固施工在小间距盾构隧道施工中至关重要,可有效降低隧道施工风险;对未加固的小间距盾构隧道施工,应保持土压平稳,加强土压精细化控制;严格控制出渣量,做好渣土改良,控制土体损失率低于0.3%;在盾壳外部注入膨润土或克泥效,可有效地减少邻近隧道的位移量;应结合实时监测数据,控制回填注浆量及注浆质量;隧道施工过程应加强对邻近既有建筑物的监测。     

Direct resolution of the pitch of DNA on positively charged lipid bilayers by frequency-modulation AFM

High resolution structural studies of DNA and DNA binding proteins by atomic force microscopy (AFM) require well-bound samples on suitably flat substrates. Adsorbing the DNA onto a positively charged supported lipid bilayer has previously been shown to be a potentially effective strategy for structural studies with AFM. Here, using our home-built frequency-modulation AFM (FM-AFM), we show that these bilayer substrates are only maximally effective for high resolution AFM when the samples are short, linear DNA, compared with circular plasmid DNA. We find that, with the former sample, the measured width of the DNA is about 2 nm, the known DNA diameter, and there is a clear height modulation along the length of the DNA with a periodicity of about 3.4 nm, in excellent agreement with the known pitch of the double helix. This sample preparation strategy is expected to enable higher resolution studies of DNA and DNA binding proteins with FM-AFM than that can presently be achieved.     

集装箱防盗措施的应用

近些年来,集装箱在运输或在堆场存放过程中,经常有箱内货物被盗的现象发生.     

轻型车制动磨损颗粒物排放与测试

美、欧研究显示,传统动力下LDV(Light Duty Vehicle,轻型车)制动磨损颗粒物的排放量为5~7 mg/km,此值高于国6b排放标准Ⅰ型试验PM(ParticulateMatter,颗粒物)限值。车辆技术配备是关键影响因素,制动能量回收可以显著降低PM排放数值,采用NAO(Non Asbestos Organic friction material,非石棉有机物混合纤维摩擦材料)技术相比少金属衬片配置的车辆其PM排放量会降低。虽然在2018年有关制动器衬片的标准规定了一部分危害身体健康的物质含量上限,但对人体危害显著的元素锑Sb却未在列,相关标准规范亟需补充。欧盟的测试方法已基本完成框架搭建和要素设定,预计2022年发布法规标准。在制动磨损测试中,速度循环、环境温度和冷却风设定对测量值有影响,分析WLTP-BrakeCycle(World Light-duty Vehicle Test Procedure-brake Cycle,全球轻型车测试规程-制动工况)是否符合我国轻型车使用规律。     

关于静电场电势零点选取的探讨

电势是物理学中一个重要的概念,从理论上讲,在计算电势时,电势零点的选取是任意的,然而在有些情况下,电势零点的选取却是受限制的,本文将探讨如何选取合适的电势零点。     

失速点上湿压缩对于跨音速压气机转子性能的影响

In order to study the effects of wet compression on a transonic compressor,a full 3-D steady numerical simulation was carried out under varying conditions.Different injected water flow rates and droplet diameters were considered.The effect of wet compression on the shock,separated flow,pressure ratio,and efficiency was investigated.Additionally,the effect of wet compression on the tip clearance when the compressor runs in the near-stall and stall situations was emphasized.Analysis of the results shows that the range of stable operation is extended,and that the pressure ratio and inlet air flow rate are also increased at the near-stall point.In addition,it seems that there is an optimum size of the droplet diameter.     

大跨刚架拱桥病害分析及加固研究

在对某座刚架拱桥进行安全检测的现场发现主拱大节点裂缝、横向联系梁破坏等病害。该文根据现场检测结果,分析了刚架拱桥常见病害形式及产生原因。采用BCI评价对该桥进行整体技术状况进行评定,并根据评定结果针对性地提出了对刚架拱桥加固的建议。其检测结果、建议加固措施对同类拱桥病害处理具有借鉴意义。