大型体育赛事对城市交通基础设施规划的影响

随着现代体育的崛起,多功能综合性体育赛事扮演的角色更加趋于多样化,大型综合性体育赛事的东道主城市可以在交通设施方面获得较大发展,尤其是有助于提高城市形象和城市交通基础设施水平。本文先从理论层面分析了大型体育赛事对城市交通基础设施规划的影响,然后结合北京奥运会、广州亚运会、济南全运会、长沙五城会等大型体育赛事的案例分析了大型体育赛事对城市交通基础设施规划的影响。最后,提出了大型体育赛事举办城市交通基础设施规划的保障措施。     

我国应急物流运作流程存在的问题与对策

我国应急物流体系还存在诸多问题,尤其是在应急物流运作流程上做得还不尽如人意。为使应急物流运作更加合理化、高效化、现代化,本文对我国应急物流运作流程的采购、仓储、运输、配送等环节存在的主要问题进行了分析,并提出了相应的解决对策。     

我国铁路口岸站物流流程规划研究

本文阐述了我国主要铁路口岸站的基本情况,并分析了铁路口岸站物流现状及存在的主要问题。根据现代物流的需求及铁路口岸作业货物的特性和流向,分别进行物流作业流程规划,并设计了现代物流条件下铁路口岸站信息系统体系结构。     

应急物流网络规划基础研究

通过阐述应急物流网络的内涵及对其进行合理规划的意义,从选址、库存、运输三个角度提出了应急物流网络规划的主要内容——应急物资储备节点空间布局、应急物资储备节点库存策略、应急物资运输及配送路径选择,最后归纳总结了应急物流网络规划的一般性步骤,以供决策者参考。     

城市应急物流军民协同机制构建

针对我国政府和军队在城市应急物流活动中存在的问题,构建了应急物流军民协同机制,包括形成机制、实现机制和约束机制。在形成机制中,分析了协同的目标、协同动因和协同优势;在实现机制中,阐述了应急物流中军民组织协同、分工协同、供应链协同和信息协同的方法 ;在约束机制中,提出了建设激励机制、信任机制和信誉机制。     

应急物流体系的建设与协同运作机制

基于物流网络与系统工程视角提出了应急物流体系的建设思路与原则,探讨了应急物流体系的构成和运作流程,并基于协同学理论分析了应急物流体系协同内涵,提出了应急物流体系协同运行机制。     

废旧电子电器回收物流网络规划——以沈阳市为例

随着人们对环境和资源问题的日益重视,资源回收物流网络的构建与发展也得到越来越多的关注。建立废旧电子电器的回收网络一方面可以解决废旧电子电器污染环境的问题,另一方面可以提高资源的有效利用率。本文以沈阳市为例,对废旧电子电器产生的数量进行分析预测,从回收物流网络运行总成本最小的角度出发,建立混合整数非线性规划模型,并用LINGO软件进行求解,得出回收网络中各物流节点的数量和分布情况。     

城市物流功能与经济的耦合机制研究

为了定量分析沧州市物流功能与经济发展的耦合协调水平,论文基于沧州市2007—2018年的数据,分析了城市物流功能与经济的相互作用机理,对二者的有序性、有序性弹性和耦合协调性进行测度,以沧州市为例进行实证分析。结果显示两个子系统的有序性、耦合协调性均呈提升趋势,耦合协调水平从2007年的严重不协调提升至2018年的勉强协调阶段。经济子系统弹性系数高于城市物流功能子系统的弹性系数,未来需加强子系统的联系与合作,推动子系统的耦合协调发展。     

大中型悬索管道跨越结构清管动力响应分析

大中型管桥是油气输送管道系统中的关键部位，呈现高次超静定、高柔性的结构特点，清管过程中形成的积液将在管桥处产生强烈的冲击动载荷作用，破坏管桥结构的稳定性。考虑悬索管道跨越结构恒载产生的初始内力、拉索垂度等几何非线性因素，将塔架简化为变截面梁，建立了悬索管桥清管动力分析有限元模型。按照管桥积液流动具有的移动荷栽一时间历程的特性，采用荷载步施加移动载荷。结合实例分析了不同清管工况条件下悬索管桥跨越结构的振动位移、临界积液长度以及临界清管速度，从而为安全清管作业提供指导依据。     

关于碳质板岩隧道大变形机理及应对措施的探讨

兰渝铁路木寨岭隧道是在高地应力、碳质板岩等软弱围岩的复杂地质条件下修建的隧道,在碳质板岩段出现了明显的大变形和局部破坏。针对木寨岭隧道的大变形,文章分析了碳质板岩大变形发生的影响因素,探究了碳质板岩的塑变、板梁弯曲、剪切滑移、压杆破坏等大变形机理,提出了调整隧道围岩受力、加强支护、超前控制等施工措施。     

Planning for economic and environmental resilience

Climate protection will require major reductions in GHG emissions from all sectors of the economy, including the transportation sector. Slowing growth in vehicle miles traveled (VMT) will be necessary for reducing transportation GHG emissions, even with major breakthroughs in vehicle technologies and low-carbon fuels (Winkelman et al., 2009). The Center for Clean Air Policy (CCAP) supports market-based policy approaches that minimize costs and maximize benefits. Our research indicates that significant GHG reductions can be achieved through smart growth and travel efficiency measures that increase accessibility, improve travel choices and make optimum use of existing infrastructure. Moreover, we find such measures can deliver compelling economic benefits, including avoided infrastructure costs, leveraged private investment, increased local tax revenues and consumer vehicle ownership and operating cost savings (Winkelman et al., 2009).As a society, what we build – where and how – has a tremendous impact on our carbon footprint, from building design to transportation infrastructure and land-use patterns. The empirical and modeling evidence is clear – people drive less in locations with efficient land use patterns, high quality travel choices and reinforcing policies and incentives (Ewing et al., 2008). It is also clear that there is growing and unmet market demand for walkable communities, reinforced by demographic shifts and higher fuel prices (Leinberger, 2006, Nelson, 2007). Transportation policy in the United States must rise to meet this demand for more travel choices and more livable communities.The academic, ideological and political debates about the level of GHG reductions and penetration rates that can or should be achieved via smart growth and pricing on the one hand, or measures such as ‘eco-driving’ and signal optimization on the other, have served their purpose: we know which policies are ‘directionally correct’ – policies that reduce GHG emissions even though we may not know the scope of those reductions. Now is the time to implement directionally correct policies, assess what works best where, and refine policy based on the results. It is a framework that CCAP calls “Do. Measure. Learn.”The Federal government is poised to spend $500 billion on transportation (Committee on Transportation and Infrastructure, 2009). CCAP encourages Congress to “Ask the Climate Question” – will our transportation investments help reduce GHG emissions or exacerbate the problem? Will they help increase our resilience to climate change impacts or increase our vulnerability? And, while we’re at it, will our investment foster energy security, livable communities and a vibrant economy? Federal transportation and climate policies should empower communities to implement locally-determined travel efficiency solutions by providing appropriate funding, tools and technical support.     

Activity planning processes in the Agent-based Dynamic Activity Planning and Travel Scheduling (ADAPTS) model

This paper describes the representation of the activity planning process utilized in a new activity-based microsimulation model called the ADAPTS (Agent-based Dynamic Activity Planning and Travel Scheduling) model, which dynamically simulates activity and travel planning and scheduling. The model utilizes a dynamic activity planning framework within the larger overall microsimulation system, which is a computational process model that attempts to replicate the decisions which comprise time-dependent activity scheduling. The model presents a step forward in which the usual concepts of activity generation and activity scheduling are significantly enhanced by adding an additional component referred to as activity planning in which the various attributes which describe the activity are determined. The model framework, therefore, separates activity planning from activity generation and treats all three components, generation, planning and scheduling, as separate discrete but dynamic events within the overall microsimulation. The development of the planning order model, which determines when and in what order each activity planning decision is made is the specific focus of this paper. The models comprising the planning order framework are developed using recent survey data from a GPS-based prompted recall survey. The model development, estimation, validation, and its use within the overall ADAPTS system are discussed. A significant finding of the study is the verification of the apparent transferability of the activity planning order model.     

常用应急抢险装备的合理选择和配备

我国自然灾害频发,地震、洪水、泥石流等灾害极容易对道路,房屋等建筑造成巨大的损坏,从而对抢险过程直接或间接地增加了难度。为了高效遂行抢险任务和提高抢险能力,就有必要提高处理交通基础设施的能力。而抢险设备的选择和合理的配置能够大大提高抢险任务效率。一方面,对于不同的抢险任务,有着不同的作业内容,其中所需要的抢险器械也各不相同。另一方面,同一种工程机械又有着不同的型号,各自又具有独特的技术性能和适用范围。一种机械可以完成多种作业,而一种作业又可以使用多种工程机械。因此如何对工程机械的选择以及合理的配置是本文的重点。     

基于模块化的综合性绿色交通考核评价体系构建及动态作用机理研究

绿色交通发展是适应新时代发展要求、交通运输行业实现节能环保健康持续发展的有力支撑。本文基于已有的绿色交通相关考核评价体系,采用模块化理论,着眼于绿色交通的政府、企业、社会三种对象,形成适用性强、针对性突出的模块化考核评价体系。     

Bi-level GA and GIS for Multi-objective TSP Route Planning

Abstract

Route planning is usually carried out to achieve a single objective such as to minimize transport cost, distance traveled or travel time. This article explores an approach to multi-objective route planning using a genetic algorithm (GA) and geographical information system (GIS) approach. The method is applied to the case of a tourist sight-seeing itinerary, where a route is planned by a tour operator to cover a set of places of interest within a given area. The route planning takes into account four criteria including travel time, vehicle operating cost, safety and surrounding scenic view quality. The multi-objective route planning in this paper can be viewed as an extension of the traditional traveling salesman problem (TSP) since a tourist needs to pass through a number of sight points. The four criteria are quantified using the spatial analytic functions of GIS and a generalized cost for each link is calculated. As different criteria play different roles in the route selection process, and the best order of the multiple points needs to be determined, a bi-level GA has been devised. The upper level aims to determine the weights of each criterion, while the lower level attempts to determine the best order of the sights to be visited based on the new generalized cost that is derived from the weights at the upper level. Both levels collaborate during the iterations and the route with the minimal generalized cost is thus determined. The above sight-seeing route planning methodology has been examined in a region within the central area of Singapore covering 19 places of interest.     

大断面黄土隧道初期支护与围岩相互作用机理研究

依托已修建并投入运营的郑西高速铁路,针对开挖面积达170m2的大断面黄土隧道,进行了不同钢架形式作用机理的研究,明确了型钢拱架和格栅拱架的适用条件;采用现场对比试验等研究手段,在浅埋老黄土隧道中分别设置了型钢钢架、格栅钢架对比试验段.试验结果表明,两种钢架初期支护变形相当;两种钢架的应力均在允许值范围之内,但格栅钢架应力较小;格栅钢架的围岩-初期支护接触压力分布较均匀;两种钢架组合支护在控制大断面黄土隧道拱顶下沉方面无明显差异,水平收敛基本相等.另外,基于混凝土早期强度试验,采用围岩-结构法,根据组合支护与围岩的特征曲线,研究分析了围岩与组合支护的相互作用机制,最终得出了格栅钢架在大断面黄土隧道中的适用条件,以及在不同围岩条件下初期支护的设计参数.