Expert S-surface control for autonomous underwater vehicles

S-surface control has proven to be an effective means for motion control of underwater autonomous vehicles （AUV）. However there are still problems maintaining steady precision of course due to the constant need to adjust parameters, especially where there are disturbing currents. Thus an intelligent integral was introduced to improve precision. An expert S-surface control was developed to tune the parameters on-line, based on the expert system, it provides S-surface control according to practical experience and control knowledge. To prevent control output over-compensation, a fuzzy neural network was included to adjust the production rules to the knowledge base. Experiments were conducted on an AUV simulation platform, and the results show that the expert S-surface controller performs better than an S-surface controller in environments with currents, producing good steady precision of course in a robust way.     

Seasonal changes in wildlife use of motorway crossing structures and their implication for monitoring programmes

Multiple factors determine the use and effectiveness of wildlife passages and crossings installed in new roads as mitigation measures against the barrier effect. It is unknown whether factors such as seasonality determine the use of these structures. This analyses the seasonality of structure used by vertebrates. Forty-eight transverse structures crossing the A-52 motorway in north-western Spain are studied during the summer and winter of 2002–03. The use of structures by terrestrial vertebrates was monitored by tracks left in marble dust and photographic systems, and comparisons carried out by means of generalized lineal methods for count data. Structural factors mostly determined the differential use of passage types by species but seasonal changes were detected both in the intensity of use and in passage selection by some species.     

桩网结构控制黄土地基工后沉降的计算与分析

为满足路基工后沉降不大于2 cm的要求,拟用桩网结构对郑西客运专线深厚黄土地基进行加固。通过有限元数值模拟计算,分析了5类不同路基断面,用不同桩长加固地基后路基的工后沉降,得出了满足沉降控制要求的桩长,供设计参考。     

赣深高铁龙南隧道大型富水断层破碎带施工技术

为解决富水铁路隧道断层破碎带极易突水涌泥的难题，依托赣深高铁龙南隧道F8断层施工，采用地表抽水试验获取F8断层破碎带岩土体渗透系数、抽水影响半径等水文地质参数，提出“地质雷达+TSP+超前钻孔”综合预测手段超前探测断层影响区，并采用“分水降压+内堵外固+安全监测”等综合处理措施。结果表明： 1）通过地表抽水试验计算得出，渗透系数为0.309 7～2.803 2 m/d，抽水影响半径为247.59～763.31 m，验明隧道断层水具有承压性，为降排水提供依据； 2）运用综合地质预报精准探测隧道掌子面DK99+435已提前进入F8断层核心区； 3）采用综合处理措施，断层水可控排放，注浆后取芯率为85%，涌水量为0.83 L/(m·min)，注浆加固效果良好。     

浅谈新型阻尼材料在汽车涂装中的应用

研究了可喷涂液体阻尼材料(Liquid Apply Sound Deadener,LASD)的阻尼性能,涂装机器人喷涂参数、材料施工操作工序等因素对涂装效果的影响。研究结果表明,在-20~50℃区间范围内,LASD的阻尼性能优于铺设热熔型沥青阻尼垫的参比样品,涂装LASD的产品车内降噪表现优于涂装沥青阻尼垫的参比样品。自动喷涂参数方面,采用枪距30~40 cm,预压1.35~2.2 MPa,线速度400~600 mm/s的喷涂参数可以获得膜厚均一稳定的最佳涂装效果。LASD温度在30~40℃区间内施工性能良好,喷涂LASD材料后放置时间过长(≥8 h)会导致材料的开裂,引起阻尼性能下降。     

杭州湾跨海大桥北航道桥北侧高墩区引桥施工

杭州湾跨海大桥北航道桥及北侧高墩区引桥为杭州湾大桥工程的第Ⅱ合同段。简要分析介绍在杭州湾水域恶劣复杂的水文气象条件下,采用栈桥施工方案的技术经济合理性。     

城市轨道交通和常规公交协调发展研究

该文从轨道交通和常规公交的特性比较入手,说明了两者协调发展的必要性;讨论了轨道交通与其他交通衔接换乘比例的确定方法及轨道交通和常规公交协调规划的原则,重点分析了基于轨道交通的常规公交线路优化中的三个关键因素,即公交线路、站点、换乘布局。     

混合动力汽车车载信息监测分析系统开发

开发了基于CAN网络的混合动力汽车车载信息监测与分析系统,它采用TMS320F2812型DSP作为核心处理单元;设计了包括CPU处理模块、通信模块、USB存储模块等硬件结构,并通过LabVIEW虚拟仪器开发平台开发了上位机监控软件;实现了混合动力汽车运行参数采集监控、故障分析、报警等功能;为混合动力电动汽车的开发提供了有力的工具.     

兰渝铁路广南段浅层天然气对隧道影响研究

在收集整理了兰渝铁路广元-南充段沿线油气田及含油气构造平面分布和油气储层资料的基础上,结合各隧道所处的构造位置和地层岩性条件,探讨了浅层天然气对各主要隧道的危险程度,指出浅层天然气对熊洞湾隧道危害大,对轩盘岭隧道和梅岭关隧道危害中等,其余隧道受浅层天然气危害小。