基于DNA算法的交通诱导系统

利用DNA计算高速并行的优点.将路段和十字路口等进行合理转化,使其成为常规的连通图.来解决交通诱导同题中的路径优化与选择.有别于遗传算法、模拟退火和神经网络等方法,文中应用DNA双螺旋结构和碱基互补配对原则对节点和边进行编码运算,提高了算法的有效性和收敛速度.最后,将DNA算法与遗传算法进行了模拟对比分析.结果表明:DNA算法可以较好地解决大规模路网遍历的NP问题,满足交通诱导的实时性、准确性要求.     

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路线方案的择优是路线设计中的最根本问题,也是路线方案选择优劣的重要环节之一。在公路路线设计中,往往存在多个可行方案,如何从众多可行路线方案中选取最优方案,是设计的关键。集对分析理论是一种处理不确定性问题的系统分析方法,基于集对分析具有概念明确、计算简便和信息全面的优点,在集对分析同一度的基础上,建立了公路路线方案优选的集对分析模型。同时,运用变异系数法确定指标权重,提高了方案评价的可信度,为公路路线方案优选提供了一种简单、适用的评价方法。     

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随着航运联营与联盟形式的出现,航运公司的船队及航线规模不断扩大,航线优化及运力配置变得更为复杂.本文结合航运业发展实际,在对传统的班轮航线配船模型进行改进的基础上,建立新的模型应用到航运联盟情况下航运公司箱位租赁决策与航线规划中.结果表明,在自身运力不足时,航运公司通过航运联盟箱位租用,对降低其系统成本、弥补航线运力、保证完成货运任务、加快船舶航班周期等的方面有突出的优点.     

物流配送路线及配送时间的优化分析

运用运筹学中的动态规划算法研究实际生活中的配送线路优化问题。通过实际调研,绘制城市道路的网络图,并通过调查获得正常情况下的交通量数据,进而通过相应的方法计算出时间并赋予网络图时间权值;通过调查赋予网络图中距离权值,分别计算出配送时间的最优线路及配送路线的最优线路,并比较说明相应的实际问题。     

V形支撑结构施工阶段的空间应力分析

采用空间有限元程序ANSYS,对某V形支撑连续梁的V形支撑结构进行施工阶段的空间应力分析,研究V形支撑结构在施工阶段时的应力分布及变化情况,为类似结构的设计提供一定的参考.     

Individual versus mass transportation: feasibility of substitution

This paper is addressed to the question of social costs and social benefits (primarily environmental) which might derive from a large‐scale substitution of so‐called mass‐transit for the present, largely private, system of automotive transportation. Energy consumption and emissions are compared for the two basic alternatives and several variants. Varying degrees of physiological tolerance to pollutants are taken into account, in an attempt to develop comparable weight‐factors for different types of emissions. It is suggested that if automobiles succeed in meeting the 1975/76 emission standards set by the Clean Air Act of 1970, rail rapid transit will probably offer no advantage (in environmental terms) unless electric power is available from virtually non‐polluting sources (e.g., natural gas or nuclear plants). Economic implications of large‐scale substitution are examined, and it is noted that such substitution would involve major restructuring of our society as a whole. However, more intensive use of mass transit in central cities, possibly in conjunction with various measures to discourage the use of private automobiles in very congested areas is feasible and likely.     

提高联网高速公路路径射频识别系统可靠性方法探析

利用标识站信息漏读漏写模型分析整个识别系统中可能出现的错误情况,提出硬件和软件解决方案.研究表明,利用数据分析查询和超时表等关键技术,可以有效提高联网高速公路路径射频识别系统的稳定性.     

直进弯出通过进路电码化问题的解决方法

排列Ⅱ道直进弯出通过进路,弯出进路采用了计算机联锁设备可以排列出八字迂回进路。由于电码化发码电路设计错误,致使Ⅱ道应发UU码而错发L码。对此进行分析,提出了切实可行的解决办法,以供后续设计参考借鉴。     

无线自组织网备份路由协议研究

传输带宽的增大使无线adhoc网络的多媒体应用日趋增多。根据多媒体应用对数据时延敏感的特点，分析无线adhoc网络动态源路由协议的优缺点，针对无线adhoc网络拓扑动态变化所带来的路由频繁中断的问题，提出基于动态源路由协议的备份路由动态源路由协议-B-DSR（Backup route DSR），并在NS2网络仿真平台上实现该协议的算法，通过与原DSR协议的比较，验证该协议算法的可行性。     

Route choice preferences: insights from Portuguese freight forwarders and truck drivers

ABSTRACT

Exploring route choice in the context of tolled alternatives can support road operators to achieve better utilization of the infrastructure, as well as maximizing revenue collection. The research presented in this paper is conducted in the context of OPTIMUM, a European Union-funded project. The research objectives include a two-component system of models that proactively calculates commercial vehicles’ toll prices. The component presented in this paper rests on the development of a route choice model that estimates the probabilities of using two alternative routes (toll road vs. national road), based on route attributes and user characteristics. To explore the usefulness of the proposed methodology a case study involving 50 truck drivers and 25 freight operators was conducted in Portugal between January 2016 and November 2017. Results from the route choice model reveal interesting insights about the role of incentives in the choice of toll roads, the perspectives of the different decision-makers and produce Values of Time for the study area.