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711.
The paper reports a modelling system to simulate goods movements at an urban scale. It allows joint analysis of choices made
by end-consumers (assumed to be families) and retailers. These movements are examined at two levels: analysis of commodity
flows, in terms of quantity, generated by the consumption of commodities; analysis of commodity flows, in terms of vehicles,
due to restocking. The first level allows us to calculate the goods quantity flows due to consumption and restocking; the
second level allows us to determine the service, vehicles used and target time, as well as the route chosen for restocking
sales outlets in order to estimate vehicle flows on the urban/metropolitan transportation network. The modelling system is
a multi-step model and considers a disaggregated approach for each decisional level. 相似文献
712.
Nazneen Ferdous Abdul Rawoof Pinjari Chandra R. Bhat Ram M. Pendyala 《Transportation》2010,37(3):363-390
This paper proposes a multiple discrete continuous nested extreme value (MDCNEV) model to analyze household expenditures for
transportation-related items in relation to a host of other consumption categories. The model system presented in this paper
is capable of providing a comprehensive assessment of how household consumption patterns (including savings) would be impacted
by increases in fuel prices or any other household expense. The MDCNEV model presented in this paper is estimated on disaggregate
consumption data from the 2002 Consumer Expenditure Survey data of the United States. Model estimation results show that a
host of household and personal socio-economic, demographic, and location variables affect the proportion of monetary resources
that households allocate to various consumption categories. Sensitivity analysis conducted using the model demonstrates the
applicability of the model for quantifying consumption adjustment patterns in response to rising fuel prices. It is found
that households adjust their food consumption, vehicular purchases, and savings rates in the short run. In the long term,
adjustments are also made to housing choices (expenses), calling for the need to ensure that fuel price effects are adequately
reflected in integrated microsimulation models of land use and travel. 相似文献
713.
Smart card systems have become the predominant method of collecting public transport fares in Japan. Transaction data obtained
through smart cards have resulted in a large amount of archived information on how passengers use public transportation. The
data have the potential to be used for modeling passenger behavior and demand for public transportation. This study focused
on train choices made by railway passengers. If each passenger’s train choice can be identified over a long period of time,
this information would be useful for improving the customer relationship management of the railway company and for improving
train timetables. The aim of this study was to develop a methodology for estimating which train is boarded by each smart card
holder. This paper presents a methodology and an algorithm for estimation using long-term transaction data. To validate the
computation time and accuracy of the estimation, an empirical analysis is carried out using actual transaction data provided
by a railway company in Japan. The results show that the proposed method is capable of estimating passenger usage patterns
from smart card transaction data collected over a long time period. 相似文献
714.
城市轨道交通事故故障应急处置相关问题研究 总被引:9,自引:5,他引:4
研究了城市轨道交通事故故障应急处置的机制及基本原则。应急反应机制和应急处理机制是应急处置机制的重要组成部分。在应急反应机制中,提出建立由高技术支持的轨道交通应急处置信息管理和发布系统,做好信息的采集、处理和发布,实现事故故障预警;在应急处理机制中,构建完整规范的事故故障预案体系,实现预案的及时更新、有效管理、方便学习和考核以及预案效果的评价和仿真。 相似文献
715.
自动驾驶汽车通过使用电脑系统来实现无人驾驶的目的 ,自动驾驶模式的应用能够有效地解决各种类型的交通事故,降低人力成本,对促进社会发展具有重要的实用意义.但自动驾驶控制技术仍然存在诸多问题,例如传感器的可靠性不强、控制系统存在漏洞等都影响着自动驾驶技术的安全性.基于以上背景,首先阐述了智能汽车自动控制系统的原理以及设计架... 相似文献
716.
Philip J. Zwart Philippe G. Godin Justin Penrose Shin Hyung Rhee 《Journal of Marine Science and Technology》2008,13(4):346-355
An accurate, efficient algorithm for solving free surface flows around ship hulls is described. Accuracy is achieved using
a compressive advection discretization which maintains a sharp free surface interface representation without relying on a
small time step. Efficiency is obtained using a solution algorithm which implicitly couples velocity, pressure, and volume
fractions. The algorithm has been implemented in a computational fluid dynamics code called CFX and is validated by means
of a comparisonwith experimental data of benchmark cases in both steady and transient conditions. 相似文献
717.
从昆明某城市下穿隧道与跨河桥梁共同设计的工程实例,介绍其设计过程中的一些重、难点,以供类似工程参考。通过多方案比选和初步估算,确定了该地质条件下合理的基础形式;然后通过几种模型的分析比较得出了较合理的地基土的竖向基床系数。通过以上计算、分析和实际施工效果表明该项目的设计是安全、经济和美观的。 相似文献
718.
工程档案资料是工程项目实施过程的记录,是工程项目形成的纲领,也是该项目的运营、后续维护和其功能、价值提升的依据和指导性文件.细致的工程实施记录能针对性地表现、体现工程个性.以地基、路基施工过程记录为例,探讨工程建设归档资料的后续价值. 相似文献
719.
720.
本文从高等职业技术教育的人才培养规格角度,较深入地研究了人才的能力培养问题.突出职业技术教育的能力培养特色,较系统地研究能力与知识的关系、关键能力与其他能力的关系和形成能力的主要培养环节等方面的理论与实践. 相似文献