倾斜荷载下群桩有限元分析方法探讨

采用Coodman单元模拟桩土界面的相互作用，利用有限元分析方法对倾斜荷载下群桩的受力特性进行探讨，并开发出适用于各种荷载形式的计算程序。工程实例分析表明，该方法能充分反映桩土作有机理及群桩作用效应，具有一定的理论意义与工程实用价值。     

路面管理系统中以PQI定义的效益模型

在路面管理系统中，效益的定义相当重要，如定义不当，则会影响决策的科学性。在我国现阶段。以用户费用的节省部分作为效益的做法欠妥当。而以路面使用性能综合评价指标PQI作为效益的评价指标更为合适。对PQI的计算方法做了改进，以加权几何平均值来计算PQI。论证了这种做法的合理性。     

南京地铁1号线一期工程施工项目中材料的采购与管理

结合南京地铁1号线工程建设实践,阐明材料采购与管理对工程建设的进度、成本、质量和安全控制的影响,说明施工项目的生产要素管理是工程建设项目部管理的重要内容,并对材料的采购供应模式和材料管理方式做出有益的探索.     

船舶阻力的相关系数及其应用

在船模拟试验和分析和基础上，提出船模阻换算为实船阻力时可应用相关阻力系数的方法。相关系数法综合考虑了实船和船模的粗糙度和船模的尺度效应，因此其估算的实船阻力一因次法和三因闪法具有更高的严谨。     

基于总线控制的船舶自动化监控系统

通过可编程控制器及CP340点到点通讯模块,对船舶柴油机的油压、油温等模拟量和水位等开关量进行监控,经实际运行表明该系统功能强、性能好、可取性高,完全能满足船舶航行的要求。     

校园无线局域网的安全性研究

介绍了校园无线局域网的优势和问题所在.分析了WLAN(Wireless Local Area Network)IEEE802.11系列安全协议的工作方式,和各自的缺陷.提出了利用Linux内核空间下的Neffilter框架,动态加载IPSec处理模块的方法,构建了一个IPSec VPN网关,以解决无线网络的安全问题,同时也能实现在线实时的信息交换和共享.     

营业线电化区段中型桥移梁施工方案的优选

在营业线电化区段进行桥梁移梁施工涉及范围广,施工难度高,对列车正常运输干扰大,对施工方案的要求较高.通过对京广线淤泥河桥移梁工程施工方案的优选,较好地解决了施工中遇到的问题,对既有线移梁施工有一定的借鉴作用.     

船舶远程识别与跟踪(LRIT)进展概况

一、船舶远程识别与跟踪(LRIT)概述船舶远程识别与跟踪(Long-Range Identificationand Tracking of Ships,简称LRIT)通过从船载自动识别系统(AIS)提取船舶识别码、船位和时间等数据,并利用全球海上遇险和搜救系统(GMDSS)的Inmarsat-C或高频设备(HF)以固定的时间间隔发送LRIT数据,经计算机对数据处理,实现船舶的远程识别与跟踪。LRIT由船     

The hydrodynamic forces acting on a cylinder array oscillating in waves and current

The problem of the interaction of multiple cylinders oscillating in waves and slow current is considered. The interaction is represented by waves emitted from adjacent cylinders towards the cylinder under consideration. Wave drift forces and moment in the horizontal plane are calculated by the far-field method based on the conservation of momentum or angular momentum. A semianalytical formula for the calculation of the wave drift damping is then deduced. The conservation of the integrals in these formulae is proved. Special treatments to improve the accuracy of results are discussed. Comparisons between calculated results and experimental measurements are made, showing satisfactory agreement. Effects of various combinations of current direction and incident wave angle on the wave drift damping and damping moment are also examined.     

A macro model for traffic flow on road networks with varying road conditions

In this paper, we develop a macro traffic flow model with consideration of varying road conditions. Our analytical and numerical results illustrate that good road condition can enhance the speed and flow of uniform traffic flow whereas bad road condition will reduce the speed and flow. The numerical results also show that good road condition can smooth shock wave and improve the stability of traffic flow whereas bad road condition will lead to steeper shock wave and reduce the stability of traffic flow. Our results are also qualitatively accordant with empirical results, which implies that the proposed model can qualitatively describe the effects of road conditions on traffic flow. These results can guide traffic engineers to improve the road quality in traffic engineering. Copyright © 2012 John Wiley & Sons, Ltd.