集装箱港口建设项目环境影响经济评价研究

为了对集装箱港口建设项目环境影响进行经济评价,首先给出集装箱港口建设项目对大气环境、水环境、声环境、土壤环境以及生态环境的环境影响因子及其对环境和社会的影响,并分析港口建设项目环境影响经济评价方法,然后运用费用效益分析方法对环境影响因子进行经济评价。     

冲击钻机海上钻孔桩施工工艺

为提高海上钻孔桩的施工效率和工程质量,结合跨海大桥钻孔桩的施工经验及海上施工特点,从钻进规程、循环系统、清孔及孔内事故的预防措施等方面研究了影响冲击钻钻进效率的各种原因,总结了冲击钻海上施工的一整套工艺。工程实例中的统计数据表明,该工艺在跨海大桥桩基施工中取得了良好的效果,充分发挥了冲击钻在海上施工的优越性,解决了常规工艺下的各种难题,适用于海上各种地质条件下的钻孔桩。     

基于广州交通模型的交通影响评估方法

介绍了＂基于广州交通模型的交通影响评估方法＂体系,阐述了应用广州交通模型把握研究项目宏观出行特征,并在此基础上建立了细部模型的技术步骤,提出了基于城市整体模型的交通影响评估方法。     

活塞蓄能器式管路阻尼器的理论与试验研究(英文)

It can be beneficial to reduce vibrations in shipboard piping, so the authors designed a new kind of piping damper with a plunger-type accumulator. Special requirements for the piping damper included low impact displacement, low speed, as well as an appropriate locking speed. Inside the damper, a plunger-type accumulator was installed and on the outside of the piston rod, a tube with exposed corrugations was added. Between the piston and the cylinder, a clearance seal was added. Using mathematical modeling, the effects of the dynamic performance of the damper’s impact displacement on vibrations were observed. Changes to the clearance between the piston and the cylinder, the stiffness of the spring in the accumulator, the throttle valve size, and locking speed resistance of the damper were respectively simulated and studied. Based on the results of the simulation, dampers with optimal parameters were developed and tested with different accumulator spring stiffnesses and different throttles. The simulation and experimental results showed that parameters such as seal clearance between piston and cylinder, accumulator spring stiffness and throttle parameters have significant effects on the damper’s impact displacement, low speed resistance and locking speed.     

着速和着角对水雷入水过载影响的数值仿真分析

为了研究高速水雷入水时受到的过载情况,采用流固耦合仿真软件MSC-Dytran,对水雷击水问题进行数值模拟仿真研究。分别计算了不同入水情况下雷体指定部位的加速度响应随时间的变化。仿真结果表明水,雷冲击载荷随入水速度的增大而迅速增大,入水速度是水雷受到的冲击载荷大小的主要影响因素。对新型水雷的结构设计、引信的设计、水雷装药的安全性设计以及其他元器件的抗冲击设计提供有价值参考。     

车用替代燃料多目标优化研究

建立了基于生命周期影响评价的车用替代燃料多目标优化模型,以车用替代燃料生命周期影响总水平值为优化目标,并以木薯乙醇为例,对车用替代燃料进行了多目标优化。结果表明,多目标优化后木薯乙醇生命周期影响总水平值降低44.7%,建议木薯乙醇在汽油中的混合比例为95%,在乙醇生产过程中使用天然气燃料。     

桥墩防撞装置评述

阐述了船舶撞击桥墩的危害性及桥墩防护的必要性,对桥墩的防撞装置进行了系统的分类和评述,总结目前国内外桥墩防撞装置的优缺点,并给出了关于防撞装置的两种设计思路.     

陆丰海洋基地码头工程防波堤平面布置

为保障泊稳条件、减轻工程对周边岸线的影响、合理降低工程投资,对陆丰海洋基地码头工程防波堤平面布置进行研究。结合波浪和潮流观测资料、遥感影像历史资料,运用波浪、潮流泥沙及岸滩演变数值模拟手段,分析陆丰海洋基地所在地水文特性,厘清不同防波堤平面布置方案下泊稳条件、波浪荷载、流场变化、泥沙运动及岸滩演变特点,探讨工程平面布置方案的优劣。经对比分析,考虑预留更多的扩建空间及分期建设的便利性,建议采用东北开口方案,暂不延长防波堤,并对受影响岸段辅以相应的岸滩整治措施。     

Designing computable general equilibrium models for transportation applications

This paper presents a review of Computable General Equilibrium (CGE) model applications for spatial economic and transport interaction modelling. This paper has three objectives (1) To deliver an up to date and comprehensive literature review on applications of CGE models in transportation, (2) To analyze the different methodological approaches and their theoretical and practical advantages and disadvantages, and (3) To ultimately provide guidance on designing CGE models for various transportation analyses. The content of the paper is as follows: first, a brief introduction to CGE models is provided. The history of CGE models is traced, ranging from their origins and seminal applications in economics, to their eventual adoption in transportation research. This is followed by a comprehensive review of the application of CGE models to transport projects and policies. Various applications in transportation are reviewed in terms of their intended application, as well as their treatment of space and time. Finally, these applications are contrasted with respect to their methodological approaches, with a close examination of various influential model choices. Here, the essential design choices made within these model applications are explained and debated, to clearly elaborate on the workings of the models and the design choices facing CGE model developers.     

灌注桩复合缺陷的低应变反射波法检测实例分析

低应变反射波法较易判断桩顶以下首个缺陷,而当灌注桩存在复合缺陷时,因缺陷反射的叠加效应将导致其他缺陷难以识别甚至影响首个缺陷的判断。结合高桩码头灌注桩低应变反射波法检测实例,分析不同类型复合缺陷的反射波曲线特征,研究复合缺陷的识别和检测方法,并提出接桩、拔除外套筒、增加护筒长度及优化泥浆更新方法、凿除桩头等验证及处理措施。