Mechanisms for Cross-Scaling, Flexibility and Social Learning in Building Resilience to Sea Level Rise: Case Study of Hampton Roads, Virginia

This case study examines how the Hampton Roads Sea Level Rise Preparedness and Resilience Intergovernmental Planning Pilot Project, a whole-of-government and whole-of-community approach to planning for and adapting to sea level rise, addressed coastal resilience in a southeastern Virginia watershed that spans multiple jurisdictions. Meeting the challenge of sea level rise requires that actors across multiple sectors—citizens, community organizations, industry and government—understand the risks and work together to make critical decisions regarding adaptation strategies and actions. The case study area includes Little Creek Amphibious Base, which is bordered by the cities of Norfolk and Virginia Beach. Adaptation responses to sea level rise by the military base and the local governments will impact each other and the residents of the area, but no cooperative agreements are in place for a joint or collaborative response. This case study examines public and private infrastructure at risk, the infrastructure interdependencies, and mechanisms for providing collaborative solutions. Engagement of area residents and other stakeholders is also integral to the process of adaptation, which includes educating about sea level rise risk and provides a mechanism for social learning that enables stakeholders to participate in critical adaptation decisions. The case study demonstrates a method to improve resiliency in the case study area and inform a regional, multi-sectoral response to sea level rise adaptation strategies.

Road Impacts on Spatial Patterns of Land Use and Landscape Fragmentation in Three Parallel Rivers Region,Yunnan Province,China

The structure and function of network is a central issue in landscape ecology.Road networks with hierarchical structure are crucial for understanding landscape dynamics.In this study,we compared the distribution of national road,provincial road,county road and rural road in the Three Parallel Rivers Region(TPRR)in Yunnan Province of China,and estimated the effect of roads(and other factors)on the spatial patterns of land use and land cover with logistic regression.In addition,we analyzed the land use and land cover change(LUCC)and landscape fragmentation in 1989–2005 along a buffer zone of the primary traffic corridor,national road G214.The results showed that,county and rural roads had much higher percentage of length extending into more natural habitats at higher elevation and steeper slope,compared with the higher level roads in this region.While the distributions of natural land cover types were dominated by environmental factors,human land use types i.e.,building land and farmland types were significantly related with roads,linking more closely with lower level roads.The LUCC dynamics(1989–2005)of the G214 buffer zone showed a general trend of land transformation from conifer forests and valley arid shrubs to building land and farmland,and from ice and snow to alpine shrubs and forests.With the length of G214 unchanged during the time,the overall landscape pattern changed little in the buffer zone,but habitat fragmentation and area decrease had occurred for the natural vegetation types,in contrast to patch mergence and expansion of human land use types,and landscape fragmentation was intensified above 2500 m a.s.l.but declined below the elevation.The results indicated the dynamics of landscape composition and patch type level distribution in spite of the stability of the overall landscape pattern,and implied the potential role of roads,especially the low level roads on landscape changes.

Effects of geometric design of forest road and roadside vegetation on traffic noise reduction

Geometric design of forest roads and design of their landscapes can reduce noise pollution and its harmful effects on human health. We investigated the effects of technical and biological parameters such as geometric road design and various roadside tree stands on reducing noise pollution according to the tree density and distance from roadway in Darabkola Forests, Sari, Iran. We recorded the noise generated by a car （Land Rover） relative to changes in longitudinal slope, horizontal curve radius and type of road pavement. We also measured noise levels according to roadside tree density and stand type （coniferous and hardwood） in 40 rectangular plots of three widths （25, 100 and 300 m） and 50 m length that were randomly demar- cated along forest roads. The changes in noise level were recorded using a decibel meter with an accuracy of q-1.5 dB and resolution of 0.1 dB. Noise levels were higher alongside unpaved roads than alongside paved roads. There was an inverse relationship between the measured noise level and horizontal curve radius. The rate of noise level on horizontal curve with a radius less than 30, 30-45 m and more than 45 m were 64.8, 70.8 and 75.9 dB, respectively. The noise level increased with the increasing longitudinal slope of the road. There was a significant difference between the noise level on slopes less than 3 % （67 dB） and 3-8 % （71.2 dB） in comparison with slopes greater than 8 % （77.8 dB）, （p 〈 0.05）. Pinus brutia L. reduced the noise level more （about 6 dB） in stands of 1/3 density of mixed hardwoods within 25 m from middle of the road. Careful design of geometric properties of forest roads as well as planting coniferous trees with hardwoods is a suitable solution for reducing noise pollution.

Determination of critical parameters in the analysis of road tunnel fires

The analysis of the fluid characteristics downstream of a fire source in transportation tunnels is one the most important factor in the emergency response, evacuation, and the rescue service studies. Some crucial parameters can affect the fluid characteristics downstream of the fire. This research develops a statistical analysis on the computational fluid dynamics(CFD) data of the road tunnel fire simulations in order to quantify the significance of tunnel dimensions, inlet air velocity, heat release rate, and the physical fire size(fire perimeter) on the fluid characteristics downstream of the fire source. The selected characteristics of the fluid(response variables) were the average temperature, the average density, the average viscosity, and the average velocity. The prediction of the designed statistical models was assessed; then the significant parameters' effects and the parameters interactive effects on different response variables were determined individually. Next, the effect of computational domain length on the selection of the significant parameters downstream of the fire source was analyzed. In this statistical analysis, the linear models were found to provide the statistically good prediction. The effect of the fire perimeter and the parameters interactive effects on the selected response variables downstream of the fire, were found to be insignificant.

Analysis of Road Traffic Noise Pollution around a University in Binzhou

The number of automobiles in the urban area of Binzhou City continues to increase,and traffic noise pollution is increasingly serious. In this study,noise pollution on Huanghe 5 Road near the south gate of Binzhou University was monitored. The results showed that the road noise pollution on Huanghe 5 Road was relatively serious on the whole,especially in the peak periods of traffic flow in the morning and afternoon,because the increase in the number of pedestrians brought inconvenience to traffic,thereby resulting in an increase in car whistle.

Evaluating the Feasibility of Road Diets for Advancing Urban Mobility in Newark, DE

Road Diets are far from a new technique for designers to apply to roadways. Yet after over 50 years of implementation and countless studies into their effectiveness, it is only relatively recently that the process is gaining widespread recognition and implementation. Each year, more states and countries are examining potential road diets and putting them into place. Still, there remains great skepticism and opposition in many corners. In addition, cities and states may be drawing from many of the same sources in how to go about the process of a road diet and evaluate them, yet their methodology, goals, and even terminology can vary from region to region. This study analyzes the implementation of a road diet along a one-way arterial road, in Newark, Delaware. The primary aim of this analysis is to evaluate the feasibility of introducing a dedicated bicycle infrastructure to enhance local accessibility and to quantify its potential impacts on traffic flow, parking availability, and loading logistics within the vicinity. While the reduction of one lane could be perceived as a constraint on traffic management, the investigation revealed that E Main Street, the roadway analyzed, for the most part, can adequately accommodate its traffic load with a single lane. Detailed findings underscore the notable enhancement in level of service and subsequent reduction in delay times across most surveyed approaches.

不同道路服务水平下连续梁桥动力响应研究

为了解不同道路服务水平与桥梁动力响应间的内在关系,以(50+100+50)m三跨连续梁桥为工程实例,采用交通流理论,引入平均车头间距与车流密度的相互关系,获取道路服务水平为一级至四级所对应的车辆间距分布规律,基于模态综合法和结构动力学原理,通过轮-桥之间的几何位移和力学耦合关系,组建多车车桥耦合时变动力分析模型,提出多车车桥耦合振动系统数值分析方法,研究不同车辆数量和不同道路服务水平下桥梁关键截面动力响应的变化规律。结果表明:随着车辆数量逐渐增加,桥梁关键截面处的挠度响应时程曲线呈先增大后减小的趋势变化,其中当桥面上的车辆数量为4辆时,桥梁关键截面的挠度响应幅值达到最大;当桥面上的车辆数量继续增加到8辆时,桥梁挠度响应幅值达到基本稳定。在此基础上,计算得出不同车辆间距变化,即随着道路服务水平由一级变化到四级时,桥梁关键截面挠度响应幅值呈增大趋势,其动力响应均大于单车作用下桥梁挠度响应幅值;而桥梁冲击系数则呈现先增大后减小的变化趋势,也均大于单车规范取值;在不同道路服务水平中均存在有利车队布置形式,使得桥梁振动响应影响较小。

基于改进DeeplabV3+的遥感图像道路分割模型

针对遥感图像道路分割边界模糊和遮挡难以区分的问题,提出了基于改进DeeplabV3+的遥感图像道路分割模型。该模型在主干网络中引入MobileNetV3和高效通道注意力机制(ECA),减少了参数量并关注连续的道路特征信息。在解码过程中采用多级上采样,增强了编码器和解码器之间的紧密连接,全面保留了细节信息。同时,在ASPP模块中采用深度可分离膨胀卷积DS-ASPP,显著减少了参数量。实验结果表明,该模型在Massachusetts Roads数据集上的交并比达到了83.71%,准确率达到了93.71%,分割精度最优,模型参数量为55.57×10^(6),能够有效地避免边界模糊和遮挡导致的错漏检问题,在遥感道路分割中提高了精度和速度。

道路和停车场拥挤程度对城市轨道交通分担率影响分析

[目的]为确定停车场拥挤程度、道路拥挤程度的最佳度量指标,需研究两者对轨道交通分担率的影响特征。[方法]提出考虑停车场个数、停车场泊位数、城市轨道交通车站步行影响范围、出行距离折减等因素的8种停车场拥挤程度的可能度量指标,以及考虑路段长度、路段拥挤度等因素的2种道路拥挤程度的可能度量指标。结合日本近畿圈交通小区间的客流数据、道路交通和停车场数据,实证分析各度量指标对城市轨道交通分担率变化的影响,利用相关性分析确定最佳度量指标。[结果及结论]增加目的地停车场拥挤程度和道路拥挤程度会提高交通小区间的全日城市轨道交通分担率。当O(起点)端交通小区位于市区和郊区时,目的地停车场拥挤程度的最佳度量指标宜采用经距离折减的交通小区内高饱和停车场泊位数占比;当O端交通小区位于核心区时,目的地停车场拥挤程度的最佳度量指标宜采用经距离折减的交通小区内高饱和停车场个数占比。道路拥挤程度的最佳度量指标宜采用经拥挤度加权的交通小区间途经交通小区的拥挤道路总延长。

市政道路平面交叉口的优化设计要点

市政道路平面交叉口是城市交通系统的重要组成部分,直接影响交通运行效率、安全性及出行的便捷性。随着城市化进程的不断推进,交通流量的增长使得交叉口的设计和优化成为解决交通拥堵问题和提高交通系统运行效率的关键。文章深入探讨了市政道路平面交叉口的优化设计要点,包括车道的优化扩展、非机动车和行人通行的安全保障、交叉口几何设计的优化,以及交通流量管理与拥堵缓解措施,为城市规划者和交通管理者提供了有益的指导,以改善城市的交通基础设施,提升出行体验,减少拥堵问题,从而为城市的可持续发展做出贡献。

市域铁路调度中心级路网综合监控系统设计

文章研究了市域铁路调度中心级路网综合监控系统设计,在明确市域铁路特点以及调度功能需求的基础上,从系统总体定位、系统设计原则、系统功能设计、系统主要构成、软硬件设计等方面出发,分析了综合监控系统设计要点,有利于减少路网运行风险,提高线路资源的集中监控和整合利用水平,推动市域铁路实现更高质量的发展。

考虑人因-环境因素的山区公路警觉水平量化模型

为描述山区公路驾驶者的警觉状态及水平,综合考虑人因-环境因素,提出了一种山区公路警觉水平量化方法。通过分析驾驶者的眼动及行为数据来确定初始观测指标,基于核主成分分析法对多源数据进行降维,对降维后的主成分使用K-means聚类方法划分高低警觉水平;以低警觉水平样本概率为目标变量,通过筛选人因-环境因素得到了警觉水平量化因子;基于评分卡方法建立了山区公路警觉水平量化模型,并对模型进行了实例验证。研究结果表明:基于人因-环境因素的山区公路警觉水平量化模型的AUC值为0.907,KS值为71.86%,模型效果较好,能为山区公路驾驶者警觉水平动态评价及安全配套设施建设提供参考依据。

“一带一路”沿线西部地区开放水平时空演进特征分析

构建沿线西部地区开放水平综合评价指标体系,运用熵值法测度分析2004—2021年开放水平及其时空演进特征,并综合归纳其空间演进格局。从时序特征看,沿线西部地区开放水平总体呈上升趋势,表现出“平稳缓慢增长—持续快速增长—短期波动增长”特点。

路网级桥梁集群监测系统建设关键技术及实践

桥梁健康监测是防范结构运行风险、提升养护管理和应急处置水平的重要举措之一,国家和行业政策对于桥梁结构健康监测系统建设提出了明确的要求。以广东交通集团路网节点桥梁集群监测系统为例,介绍了路网级桥梁监测系统的技术路线、总体架构、关键技术和建设实践,可为地市级、路网级桥梁健康监测系统的构建提供参考。

环岛出口道人车冲突影响因素分析

为有效降低行人与车辆之间冲突的潜在风险,尽可能地避免交通事故的发生,对行人行为特性影响因素与交通冲突之间的联系进行了研究,选取了长春市人民广场处环形交叉口的3个出口道,以交通冲突数据为基础,进行有关行人因素的人车冲突严重程度分析;收集高峰时段的人车冲突数据,选取合适的交通冲突指标,聚类分析得出不同种类交通冲突的阈值以及不同类型人车冲突的严重程度,引入危险度的概念得出小型出口道危险性比大型出口道危险性大的结论;进一步探究行人特性与人车冲突的相关性,发现行人违章率与冲突之间存在正线性关系,行人在即将发生冲突时注视方向由车辆方向到过街方向会大大减少冲突发生。

占道施工影响下区域路网容量计算与关键路段识别方法

为研究占道施工事件对区域路网络容量的影响,基于双层规划理论,构建了考虑路段通行能力约束的区域路网络容量计算模型,并设计了求解算法。通过VISSIM仿真软件,确定了施工区段通行能力基准值,对实际通行能力与各影响因素之间的定量关系进行分析,给出了占道施工条件下实际通行能力计算方法。结合交通流分配结果、边介值、蓄意破坏前后路网效率变化率给出了占道施工期区域关键路段识别方法。最后以哈尔滨市阿城区的路网为案例,通过手机信令数据获取得到出行需求分布,计算占道施工前后的路网容量,并对占道施工期阿城区路网进行了重要度排序。研究表明:初始条件下区域路网络容量为38 445 pcu/h,施工时为36 865 pcu/h,路网络容量值减少了4.1%。

城市道路信号平面交叉口合理间距研究

平面交叉作为城市道路的关键节点,其合理净距的取值直接影响到整条路段车辆的行车安全和通行效率。文章统计分析了平面交叉口由于间距过短所引发交通事故的原因,基于交通流理论、车辆加减速方式、统计学和概率论原理、驾驶员操作习惯等建立了平面交叉口合理间距的计算模型,得到不同设计速度、车道数情况下平面交叉口合理间距的取值。

运营公路高位崩塌危岩体监测技术研究现状浅析

崩塌地质灾害受到地形条件约束,一般在峡谷地带尤其发育。地形陡峻、沟谷深切,加之强烈的风化作用影响,导致运营公路在峡谷路段安全风险剧增。该文通过文献调研简述了崩塌地质灾害的成因类型,总结为倾倒式、滑移式、错断式、拉裂式和鼓胀式五类;危岩落石的运动特征复杂,受地形条件控制表现出崩落、跳跃、滚动、抛散等形式。该文分析了高位危岩对公路设施的危害及其特点,论述了当前崩塌危岩体监测的主要技术手段及其优越点。基于该领域的研究现状,初步提出了适用于运营公路高位危岩的监测思路:无人机贴近倾斜摄影测量快速识别→危岩体与监测区段划分→视频/激光雷达图像识别监测→监测预警与应急处置。该文提出的监测思路旨在崩塌发生后迅速预警,可有效应对次生灾害的发生,减少灾害造成的进一步损失,赢得抢通救灾的宝贵时间,对山区公路类似情况具有一定的参考价值。

数字化城市道路分级研究

在数字化城市道路现行政策体系、标准规范的基础上,结合我国特色、相关前沿技术发展及数字化城市道路项目建设成效,进一步规范不同应用场景下数字化城市道路建设的技术标准,明确了数字化城市道路的含义和等级划分。针对城市道路在感知分析、管控和服务等能力维度下的差异性,提出L1~L4四个等级,明确每个等级的功能要求,对数字化城市道路的建设提供技术支撑和指导。

改进ARRB模型下的平面交叉口信号配时优化

道路交叉口的通行能力是道路服务水平的重要组成部分,交叉口信号配时的优化是改善通行能力、提高车辆运行效率的重要手段。以某道路交叉口为例,进行实地调查并收集相应数据,运用Vissim软件对其进行模拟仿真,并输出最大排队长度、停车延误和人均延误等参数。根据相关标准对该道路交叉口运行状况进行评价,通过ARRB信号周期模型对该道路交叉口的绿灯时长进行优化,运用Vissim软件进行模拟并输出相关参数,与优化前各参数进行对比。结果表明:在优化后的信号配时方案下,平均最大排队长度下降29.83%,平均停车延误下降40.17%,平均人均延误下降34.49%,该道路交叉口的通行效率显著提升。