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991.
通过对我国公路工程概预算人工费标准的形成和发展过程的研究,结合当前公路行业人工费标准的现状,提出了确定公路工程定额人工费标准的思路和方法。 相似文献
992.
在项目建设整个过程中,可行性研究阶段是公路工程建设项目的最重要阶段,其工作质量直接影响项目的决策水平和项目功能定位及目标的实现,对项目建成后的功能和效益发挥产生直接影响。项目可行性研究涉及内容较多,对其进行全面分析研究是必要的,但也要学会抓主要矛盾,对所研究的问题要有所侧重。就山区公路建设项目可行性研究中的交通量预测、路线方案选择以及经济评价等方面需重点研究的问题进行了探讨。 相似文献
993.
讨论公路工程造价中出现的一些常见问题,提出合理编制工程造价的措施和方法,可为相关项目提供参考和借鉴依据。 相似文献
994.
The impacts of the already decided increase in rail infrastructure charges in Sweden are described for various market segments within the rail transport system and on the aggregate level for society as a whole. The need for complementary measures in the road transport system is also discussed. Likewise, the paper also mentions the impact of increased rail infrastructure charges on certain significant industrial sectors. An increase in rail charges may reduce social welfare even though the reduction in rail transport mileage is small. This is mainly due to large non-internalised absolute externalities for road freight. For commuter trains, the infrastructure charges' share of the costs of rail transport is expected to rise to 13 percent, which in an international perspective still will be small. 相似文献
995.
上海开始了新一轮城市总体规划,而市郊轨道交通网络规划对城市总体规划影响很大。为了给上海都市圈市郊轨道交通网规划提供启发,选择了与上海有可比性的东京都市圈作为研究对象,较深入地剖析了东京都市圈市郊轨道交通的供需特征;分圈层比较了东京都市圈与上海都市圈的相关统计数据,得到了东京都市圈郊区圈层的4类轨道交通的长度及放射线、周向线的供给分布特征和郊区圈层的径向、周向及过境出行需求特征,以及供需二者之间的关系特征。在此基础上得到启示,对上海都市圈市郊轨道交通网规划提出了建议。 相似文献
996.
文章研究了现行的三种业绩评价系统的发展历程以及我国业绩评价系统的不足,并提出了构建业绩评价系统的具体改进思路,具有一定的参考价值。 相似文献
997.
Wen-Hong Liu Kun-Lung Lin Hao-Tang Jhan Ta-Ly Lin De-Lu Ding Ching-Hsien Ho 《Coastal management》2013,41(5):515-535
A sustainable fisheries development indicator system (SFDIS) is proposed in this article to monitor management of Taiwan's offshore and coastal fisheries. Demonstration of its application shows that the ecological index is tending toward sustainability but to conserve fisheries’ resources it is necessary to strengthen habitat protection and management through a partnership approach. The economic index is tending toward unsustainability as a result of a decline in fisheries’ Gross Domestic Product (GDP), value, economic production, and investment. An aging fisherman population and decreasing social performance and resilience contribute to unsustainability of the social index. By contrast, the institutional index is sustainable because of improved management efficiency, ability, and capacity-building. However, some problems exist with regard to compliance and acceptability of institutional expense. Overall, the SFDIS suggests that an increase in employee number, incorrect statistical data, and unacceptable institutional expense will make Taiwan's offshore and coastal fisheries unsustainable in the long run. 相似文献
998.
Md. Tazul Islam 《运输规划与技术》2013,36(4):409-426
Abstract Trip chaining (or tours) and mode choice are two critical factors influencing a variety of patterns of urban travel demand. This paper investigates the hierarchical relationship between these two sets of decisions including the influences of socio-demographic characteristics on them. It uses a 6-week travel diary collected in Thurgau, Switzerland, in 2003. The structural equation modeling technique is applied to identify the hierarchical relationship. Hierarchy and temporal consistency of the relationship is investigated separately for work versus non-work tours. It becomes clear that for work tours in weekdays, trip-chaining and mode choice decisions are simultaneous and remain consistent across the weeks. For non-work tours in weekdays, mode choice decisions precede trip-chaining decisions. However, for non-work tours in weekends, trip-chaining decisions precede mode choice decisions. A number of socioeconomic characteristics also play major roles in influencing the relationships. Results of the investigation challenge the traditional approach of modeling mode choice separately from activity-scheduling decisions. 相似文献
999.
介绍了复合地基技术的研究现状。结合在北良港淤泥吹填区建设一座轻钢结构火车铁路罩棚的工程实例,介绍了复合地基技术中的多种类型,如强夯置换碎石桩复合地基、刚性桩复合地基、夯实水泥桩等的计算方法,总结了设计、施工和检测等实际经验,并得出了相关的结论,以期为国内复合地基技术的研究提供一定的参考。 相似文献
1000.
A macroscopic taxi model for passenger demand,taxi utilization and level of services 总被引:1,自引:0,他引:1
In most urban areas taxi services are subject to various types of regulation such as entry restriction and price control.
However, effective intervention depends on generating and using suitable information on the demand-supply equilibrium of the
taxi market. This paper develops a simultaneous equation system of passenger demand, taxi utilization and level of services
based on a taxi service situation found in the urban area of Hong Kong over the last ten years. A set of variables is introduced
including number of licensed taxis, taxi fare, disposable income, occupied taxi journey time as exogenous variables and daily
taxi passenger demand, passenger waiting time, taxi availability, taxi utilization and average taxi waiting time as endogenous
variables. These variables are coupled together through a system of nonlinear simultaneous equations whose parameters are
estimated from survey data. The simultaneous equation system can be used to obtain useful regulatory information to assist
with the decisions concerning the restriction over the number of taxi licenses and the fixing of the taxi fare structure as
well as a range of service quality control.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献