满足摩托车第3阶段排放标准的电喷技术研究

针对日益严格的摩托车排放标准和法规,本方案进行了电喷摩托车方案设计及软件控制研究,并对电喷发动机进行了标定。通过测试表明,摩托车采用闭环电喷系统 三元催化转化器技术能够有效降低摩托车有害污染物的排放量,满足我国将要实施的摩托车第3阶段排放标准的要求。     

洋口人工岛工程的合龙设计与实施

洋口人工岛是南通洋口港区陆岛跨海通道的终点、现代物流仓储的基地和液化天然气接收站的承载平台。文章以洋口人工岛工程为例,以水力计算为理论依据,从龙口的合龙时机、龙口位置和宽度确定、龙口防护、堵口方法和顺序以及龙口合龙过程中需注意的要点几个方面对龙口的合龙进行了分析和探讨。     

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。     

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。     

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.     

古石背隧道岩溶段的综合治理

溶洞洞穴的存在易造成隧道围岩塌陷压垮二衬或悬空造成开裂等病害,给隧道施工、运营安全造成威胁.针对古石背隧道施工在隧道拱顶、侧面、拱脚、仰拱底部等位置出现岩溶洞穴的情况,根据溶洞对隧道不同影响和施工条件,采用了清除充填物、回填片石夯实或砼、注浆加固填充物、钢筋砼护拱、钢筋砼板跨越、封闭地表塌陷、疏排地表水等综合治理措施,施工结果表明治理是成功的.     

梁腹板开圆孔节点的分析模型

在距柱表面一定距离的梁腹板上开设一定大小的孔洞是改善钢框架结构抗震性能的一种有效手段,文中结合试验结果提出了梁腹板开圆孔节点的分析模型．为了能够在结构的弹塑性分析中考虑梁腹板开圆孔节点的影响,除在梁端、柱端设置塑性铰外,还应在腹板孔削弱处增设塑性铰．新增塑性铰位于腹板削弱区域最危险截面处,其弯矩一转角关系与普通实腹式钢梁一致,仅屈服点存在一定的差异．利用该模型对梁腹板开圆孔节点的拟静力试验及含梁腹板开圆孔的钢框架抗震性能试验进行了模拟,其结果能满足工程要求．