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111.
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation.  相似文献   
112.
The second part of the state-of-the-art focuses on the development of the founders' double streams explaining single-outcome indicators (probability of accidents and fatalities, respectively) by fixed form regression, as outlined in the Part 1. Following Page (1997, pp. 67–122, 2001) and others, we use as turning point of the evolution of both aggregate and discrete approaches the DRAG-1 model of 1984, itself based on aggregate data, which introduced four key innovations in principle applicable to both streams.  相似文献   
113.
为识别区域综合交通系统能耗驱动因子,测算其对系统能耗的贡献度,将驱动因素分为规模效应、结构效应和技术效应,采用ASIF数据构造原理和时序列回归法识别各因子的相关性,运用迪氏分解方法建立扩展LMDI分解模型,计算各因子能耗贡献度.计算表明,规模效应和技术效应的影响程度在逐渐减弱,结构效应的影响程度在逐渐增加;运输结构还需要进一步优化,对系统能耗的影响还有很大下降空间;近年来能耗效率已经得到很大提高,但能耗效率对能耗的贡献正在逐渐减弱,未来提高运输强度对降低能耗有明显效果.经实证检验,计算模型可靠、结论可信,能为区域综合低碳交通政策制定提供更科学的依据.  相似文献   
114.
Abstract

In this paper, we present a dynamic traffic assignment-simulation modeling framework (DYNASMART-P) to support the evaluation and planning of Bus Rapid Transit (BRT) services in urban transportation networks. The model represents the different characteristics associated with BRT operations such as: exclusive right-of-way lanes, limited-stop service, signal prioritization at congested intersections, and enhanced bus stops to reduce passenger boarding times. A set of simulation experiments is conducted using the model to study the impact of introducing a hypothetical BRT service in the Knoxville area in the State of Tennessee. In these experiments, the different operational characteristics of BRT are evaluated in terms of potential impact on transit ridership and on the interacting auto traffic. The results illustrate the advantages of BRT for increasing transit ridership and improving overall system performance.  相似文献   
115.

The Dutch National Institute of Public Health and Environmental Protection publishes Environmental Outlooks in which 25‐year projections are made. These Outlooks quantifying the environmental problems, form the scientific basis for Dutch environmental policy. Traffic and transport is one of the main sectors causing environmental problems. The emissions and energy use of all relevant categories (road traffic, non‐road traffic) are based on model simulations with models. This paper describes the main models used.

If present policy is implemented only a minority of the environmental targets will be met.

If a sustainable transport system for the Netherlands means a large reducton in CO2 emissions and energy use after 2010 a stronger emphasis on both technical and non‐technical measures (such as land‐use planning combined with public transport improvements) for the period until 2010 is needed than proposed in the Second Transport Structure Plan, unless a sustainable energy source becomes available.  相似文献   
116.
针对当前交通拥堵、能源紧张、尾气污染等一系列问题,为加快快速公共交通的发展、提高公共交通利用率,本文找出了影响快速公交客流的主要因素,利用系统工程学中的ISM方法,构建了快速公交客流系统解释结构模型,通过分析探讨快速公交客流的主要影响因素,进而明确了各因素间的清晰结构,得到影响快速公交客流量的5级递阶结构;最后找出影响快速公交客流因素的各影响因素.通过影响因素,建立了多元回归模型,从影响程度、影响方向、影响时期分别归类分析.通过分析各层级因素对快速公交客流量的影响,可引导更多居民选择快速公交出行,对缓解交通压力提供了一定方法指导和决策支持.并通过合理分析为快速公交运输服务提出了建议.  相似文献   
117.
This paper sets out the rationale and structure of a tool for assisting policy-makers and practitioners to understand behavioural challenges and open up thinking on the design of effective ‘behaviour change’ interventions. The ‘Four Dimensions of Behaviour’ (4DB) framework is based on the theoretical and empirical research in a range of policy domains including transport and pro-environmental behaviour more generally. The 4DB framework characterises multifaceted behaviours along dimensions of actor, domain, durability and scope. Its application in workshop or structured settings opens up diverse and non-exclusive discussion on designing interventions to match salient behavioural characteristics. The use of the 4DB framework in the transport domain is demonstrated for travel behaviours of interest to policy-makers using examples of buying plug-in vehicles (PiVs), commuting by bicycle, eco-driving and making business trips by train.  相似文献   
118.
结合大庆市油田用地变更调查实际,阐述CORS技术的发展及应用现状,重点介绍在油田用地变更调查中应用CORS系统的实际经验,分析CORS技术在油田土地管理应用中的特点,并对其测量精度进行评价。  相似文献   
119.
该文针对"白改黑"和"白加黑"工程中出现的反射裂缝,提出用共振破碎技术彻底解决这一长期困扰工程界的技术问题。并且对以前和现在常用的处理方法进行比较,阐明为什么要将板块破碎,破碎的机理是什么,用工程实例说明破碎法处理裂缝的后期效果。其内容对类似工程有一定的借鉴和参考作用。  相似文献   
120.
浦东南路、耀华路是规划城市主干道,浦东新区路网规划中沿江地区的重要骨架道路之一,也是2010年上海世博会重要通道之一。该文介绍了在道路设计中,以交通为前提,并融入世博会"和谐城市"的规划理念、"城市·让生活更美好"以及"勤俭办博"的主题。  相似文献   
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