城市公共交通发展的动力机制研究

城市公共交通发展动力涵盖政府的主导作用、公交运营企业的主动力、公众的支持力以及营销传播的助动力等"四方力量",四方力量的协同推动城市公共交通系统快速发展。首先对城市公共交通发展的动力机制进行分析,研究快速发展面临的困境以及进行公共交通系统动力协调的必要性;然后提出强化政府主导作用的"4P"发展策略、激发公交运营企业主动力的品牌服务策略、拓展公众支持力的乘客关系管理策略、发挥营销传播助动力的促销策略等公共交通协同发展策略;由此增强公共交通竞争力,提高公交出行方式分担率,推动城市可持续发展。     

带支撑梁的船闸闸室裂缝成因分析

针对某船闸闸室施工期在支撑梁上部出现表面裂缝的问题,基于有限元原理,分析闸室表面裂缝的成因及分布规律,并提出防止表面裂缝产生的温控措施.分析结果表明:早期在支撑梁上部出现表面裂缝主要是因为内外温差以及支撑梁对新浇筑混凝土的约束作用;在控制浇筑温度的基础上,采取表面保温和内部水管冷却相结合的温控措施,可以将表面点的抗裂安全系数提高至1. 40.该方案在后续施工应用后未出现表面裂缝,达到了良好的防裂效果.     

A new composite decision support framework for strategic and sustainable transport appraisals

This paper concerns the development of a new decision support framework for the appraisal of transport infrastructure projects. In such appraisals there will often be a need for including both conventional transport impacts as well as criteria of a more strategic and/or sustainable character. The proposed framework is based on the use of cost-benefit analysis featuring feasibility risk assessment in combination with multi-criteria decision analysis and is supported by the concept of decision conferencing. The framework is applied for a transport related case study dealing with the complex decision problem of determining the most attractive alternative for a new fixed link between Denmark and Sweden – the so-called HH-connection. Applying the framework to the case study made it possible to address the decision problem from an economic, a strategic, and a sustainable point of view simultaneously. The outcome of the case study demonstrates the decision making framework as a valuable decision support system (DSS), and it is concluded that appraisals of transport projects can be effectively supported by the use of the DSS. Finally, perspectives of the future modelling work are given.     

船坞超高型管柱支撑设计

阐述了船坞超高型管柱支撑的设计。提出了船坞区域搭载时管子支撑与外板3种连接形式下的支撑设计允许承载力的理论计算，并对目前船坞使用的φ426mm×14mm和φ500mm×18mm两种管子进行计算分析。改进了撑管的底部支撑，提高了超高型管子支撑的使用效果和安全性。     

舰船物资转运方案计算机辅助决策算法研究

瞬息万变的现代战场对大中型水面战斗舰船甲板物资转运的效率提出越来越高的要求。引入计算机辅助决策技术,在考虑多种牵制因素的情况下,快速获得最优的物资转运方案。详细分析和阐述舰船物资转运线路规划、时间计算、作业排序以及资源配班等4个主要问题的计算机解决方法,为利用计算机辅助制定最优物资转运方案提供可行途径。     

Short-term forecasting of high-speed rail demand: A hybrid approach combining ensemble empirical mode decomposition and gray support vector machine with real-world applications in China

Short-term forecasting of high-speed rail (HSR) passenger flow provides daily ridership estimates that account for day-to-day demand variations in the near future (e.g., next week, next month). It is one of the most critical tasks in high-speed passenger rail planning, operational decision-making and dynamic operation adjustment. An accurate short-term HSR demand prediction provides a basis for effective rail revenue management. In this paper, a hybrid short-term demand forecasting approach is developed by combining the ensemble empirical mode decomposition (EEMD) and grey support vector machine (GSVM) models. There are three steps in this hybrid forecasting approach: (i) decompose short-term passenger flow data with noises into a number of intrinsic mode functions (IMFs) and a trend term; (ii) predict each IMF using GSVM calibrated by the particle swarm optimization (PSO); (iii) reconstruct the refined IMF components to produce the final predicted daily HSR passenger flow, where the PSO is also applied to achieve the optimal refactoring combination. This innovative hybrid approach is demonstrated with three typical origin–destination pairs along the Wuhan-Guangzhou HSR in China. Mean absolute percentage errors of the EEMD-GSVM predictions using testing sets are 6.7%, 5.1% and 6.5%, respectively, which are much lower than those of two existing forecasting approaches (support vector machine and autoregressive integrated moving average). Application results indicate that the proposed hybrid forecasting approach performs well in terms of prediction accuracy and is especially suitable for short-term HSR passenger flow forecasting.     

一个应用复合箱体结构传动箱的柴油发电机组设计

因运载车辆或其它条件限制,在某些情况下,柴油发电机组设计中需将发电机布置在柴油发动机的侧面,以减小机组在长度方向的尺寸。本文对该种布置方式的力学特性进行了分析,并从传动齿轮箱设计和柴油发电机组结构总成方面提出了合理的设计方案,产品经运行效果良好,证明具有使用价值。     

基于支持向量机的装载机齿轮箱故障智能诊断研究

在分析现有齿轮箱故障诊断方法的基础上,提出了采用多分类器支持向量机齿轮箱故障智能诊断方法,简介了该方法的系统结构、实现原理、特征提取与故障类别,重点讨论了齿轮箱故障多分类器支持向量机智能诊断模型与算法。仿真试验结果说明了采用多分类器支持向量机智能方法进行齿轮箱故障智能诊断的可行性与正确性。     

一种适用于大变形支护的新型可伸长锚杆

支护理论的发展对锚固技术提出了新的要求,即要与围岩变形相协调,允许围岩可控变形,充分发挥围岩的自支撑能力。基于此设计了一种适用于大变形支护的新型可伸长锚杆,该型锚杆在达到初始锚固力后,在保持与围岩协调变形的伸长过程中锚固力可基本保持恒定,达到围岩许用变形形值后,锚固力急速上升。室内与现场试验证实了新型可伸长锚杆协调围岩大变形的优良性能,可在围岩大变形支护中推广应用。可伸长。     

基于分层壳元法多梁式T梁的极限承载力评估

基于分层壳元法,对钢筋混凝土多梁式T梁的极限承载力问题进行了研究。建立实体退化壳元模型后,推导了壳元位移场,用分层壳元模拟了多梁式T梁。基于Owen理论考虑了混凝土的材料非线性,并基于V.Karman假设考虑了结构的几何非线性。通过多梁式T梁实例分析,结果表明,应用分层壳元法能正确地进行多梁式T梁的非线性分析,能有效地评估结构的极限承载力,且支承形式对多梁式T梁的极限承载力有很大影响,研究表明应选择修正的铰支-弹性支承形式。