Economic factors affecting the registration of lower CO2 emitting aircraft in Europe

We examine the various forces influencing the development and uptake of environmentally beneficial technical changes, focusing on airline technology. Within this context, we consider not only the nature of competition within the final market in which aircraft, an intermediate product, are sold, but also that of the product market itself, the commercial airline industry. The reasons for the gradual reduction in CO₂ per seat per aircraft movement in aircraft design are examined in terms of the real costs of aviation fuel, changes in the nature of the supply industry, the movement towards carbon cap-trade policies, and endogenous technical progress in the technology of the industry. The latter being taken as an empirical proxy for the role market forms play in influencing the fuel efficiency of the types of aircraft used. The results support the existence of these latter forces on the demand for aircraft types, allowing for other influences that affect aircraft technology.     

Optimal funding allocation strategies for safety improvements on urban intersections

Urban intersections crashes cause significant economic loss. The safety management process undertaken by most states in the United States is referred to as Highway Safety Improvement Program and consists of three standardized steps: (i) identification of critical crash locations, (ii) development of countermeasures, and (iii) resource allocation among identified crash locations. Often these three steps are undertaken independently, with limited detail of each step at the state planning agencies. The literature review underlines the importance of the third step, and the lack of sophisticated tools available to state planning agencies for leveraging information obtained from the first two steps. Further, non-strategic approaches and unavailability of methods for evaluating policies may lead to sub-optimal funding allocation. This paper overcomes these limitations and proposes multiple optimal resource allocation strategies for improvements at urban intersections that maximize safety benefits, under budget and policy constraints. Proposed policy measures based on benefits maximization (economic competitiveness), equitable allocation (equity), and relaxation of mutually exclusiveness (multiple alternatives at one location) produce significantly different alternative and fund allocation. The proposed models are applied to selected intersections in four counties of southeast Michigan. Results reinforce the applicability of the strategies/policies and tools developed in this paper for safety project funding allocation on critical urban intersections.     

考虑堆填界面软化及地下水位波动的大型弃渣场边坡稳定性分析

弃渣场是基础建设中的重要附属设施,近年来业界对弃渣场边坡稳定与安全十分关注.针对弃渣场长期运行中堆填界面软化和地下水位波动这2种典型致灾因子,本文在地质补勘、岩土试验和变形监测的基础上,采用强度折减有限元法模拟研究了一大型弃渣场的典型失稳机制和稳态演化规律.研究发现由于地表入渗的长期淋溶和地下水浸润作用,依附堆填界面产生黏粒充填现象和强度软化效应,从而诱发依附堆填界面的应变局部化,导致边坡潜在失稳模式的转变、松动区的扩大和边坡稳态的下降,弃渣场设计与运行过程中,应对堆填界面软化效应予以重视.对监测数据反映的雨季地下水位上浮2m的工况进行校核计算,以及地下水位进一步抬升条件下的边坡稳态模拟预测,表明在遭遇极端降雨事件或排水设施失效等恶劣工况下,该弃渣场具有安全储备不足的风险,因此需要加强地下水位监测和地下排水设施维护,保障弃渣场边坡的长期稳定与安全.本文提出的评价思路、方法和成果可供类似弃渣场边坡稳定性评价借鉴.     

基于雨量光线传感器的雨刮灯光智能控制系统

本文介绍一种车辆雨刮灯光智能控制系统,基于系统雨量光线传感器的雨量大小及光照强度的信号采集,增加雨刮AUTO开关和灯光AUTO开关,通过车身控制器对开关信号、雨量大小及光照强度的判断,实现手自一体的智能灯光雨刮控制功能。系统智能化程度高,有助于减少驾驶员的重复手动操作,提高车辆的驾驶舒适度。     

BIM协同平台在水运工程施工管理中的应用

以广州南沙国际邮轮码头项目为依托,搭建BIM协同管理平台,对平台进行二次开发,建立项目层级数据库,并在施工过程中进行应用。结果表明,BIM协同管理平台在生产进度管理、质量安全管理、资料管理等方面为项目管理提供了良好的支撑作用,简化了项目部工作管理流程,减少了工作量,提高项目部的管理效率和工程的施工质量。     

驾驶人“感知-决策-操控”行为模型

为准确模拟驾驶人跟车行为，提出基于隐马尔可夫模型(Hidden Markov Model，HMM)的驾驶人“感知-决策-操控”行为模型。建立描述驾驶意愿的HMM模型，模拟驾驶人感知过程，获得期望的车间距；预测模块模拟驾驶人根据交通环境和自身生理、心理状态预测车辆未来轨迹，即决策过程；优化模块描述驾驶人为使预测的车辆轨迹跟踪上期望的车辆间距而采取的操控汽车的执行动作，即操控过程。上述3个模块的滚动过程实现了对驾驶人跟车行为的模拟。利用自然驾驶数据进行算例分析，结果表明，本文模型预测车间距平均误差仅为1.47%，证明了所建模型的有效性及准确性。本文为驾驶行为建模方法的理论研究和应用拓宽了思路。     

富水砂层地下连续墙施工质量控制措施探讨

南通市特有的富水砂层地质对地下连续墙成墙质量影响较大。南通市轨道交通1号线基坑开挖过程中,部分地下连续墙墙面出现较大鼓包、漏筋等缺陷。通过分析发现在没有槽壁加固的情况下,采用降水与优化泥浆配比等措施可较好地控制缺陷发生,可为后续城市轨道交通建设提供参考。     

移动式损管训练舱堵漏水循环系统设计

文章通过3ds Max和AutoCAD软件设计出移动式损管训练舱堵漏水循环系统,在系统中完善了堵漏训练所需的配套设施,解决堵漏水的循环利用,使损管堵漏训练能满足海警官兵日常训练要求.     

地铁信号调试漏流保护器选型及应用

通过介绍漏流保护器原理、各级漏流保护器参数规范、工程实践中案例,来说明在地铁建设期间漏流保护器选型对信号调试的重要性。     

引绰济辽输水工程顶管机刀盘关键技术研究

为选配更具适应性的刀盘，对引绰济辽输水工程配置多梯度二次周边锥破机构的辐板式刀盘和面板式刀盘2种不同结构形式刀盘进行关键结构设计研究。采用有限元法得到结构的应力分布规律，通过数值计算得到刀具布置在力学性能上的分布情况。结果表明： 1）辐板式刀盘开口率更大，尤其中心区域开口大，针对黏土、泥砾等复合地层，“结泥饼”的可能性会降低； 2）2种刀盘结构形式均能满足结构强度要求，其中面板式刀盘结构强度更具优势； 3）面板式刀盘的类“米字形”滚刀布置方式产生的径向不平衡力和倾覆力矩更小，2种结构方式的数值均较小，满足设计要求； 4）综合工程地质情况、结构形式、强度分析、刀具布置、力学性能及其他多方面因素考虑，选择辐板式刀盘结构作为本工程的刀盘主体结构。通过在工程项目中的实际使用情况可知，刀盘掘进中运行稳定，具有良好的地质适应性，满足施工要求。