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1.
口岸作为国家指定的对外开放门户,承担着国与国之间货物运输和人员往来的重要功能。"一带一路"倡议的实施促进了我国口岸的发展,带动了口岸经济与区域经济的发展,反过来进一步加强了与"一带一路"沿线国家的合作。本文利用口岸运行指标中的出入境货运量数据,借助探索性空间数据分析方法,对我国2011—2017年31个省(区、市)的口岸出入境货运量的时空格局进行分析。结果表明:"一带一路"倡议提出后,尤其是2015年后,我国口岸出入境货运总量呈现快速增长态势且存在显著的空间正相关性;三类口岸(水运、陆运和空运口岸)中,水运口岸存在更显著的、更强的空间相关性;各类口岸出入境货运量中,东部沿海地区水运呈现正向空间集聚现象,西部沿边地区陆运呈现极化现象。此外,本文对全国31个省(区、市)的地区货运总量也进行了空间动态分析,发现也存在空间相关性,且集聚效应在"一带一路"倡议提出后不断增强。在此基础上,为了更好地服务于"一带一路"建设,本文提出了提升各类口岸运输能力的相关对策建议。  相似文献   
2.
A yard template determines the assignment of spaces in a yard for arriving vessels. Fluctuation of demand for freight transportation brings new challenges for making a robust yard template when facing uncertain maritime market. A model is proposed for yard template planning considering random numbers of containers that will be loaded onto vessels that visit the port periodically. Traffic congestions and multiple schedule cycle times for vessel arrival patterns are also considered. Moreover, a meta-heuristic method is developed for solving the model in large-scale cases. Numerical experiments are conducted to validate effectiveness and efficiency of the model.  相似文献   
3.
The main objective of this study is to investigate the inclusion of lateral transhipment opportunities into the humanitarian relief chain and to examine the effect of different parameters on minimizing the average distance travelled per item while serving the beneficiaries. Direct shipment model (DT), lateral transhipment model (LTSP) and maritime lateral transhipment model (MLTSP) are developed and compared between each other by using a real life earthquake scenario prepared for the city of Istanbul by JICA (Japanese International Cooperation Agency). Developed mathematical models decide on the locations and number of disaster relief facilities, quantity of relief items to hold at those facilities, and quantity of lateral transhipment between the facilities. Vulnerability of the roads and heterogeneous capacitated facilities are also considered. It can be concluded that both LTSP and MLTSP models gave better results than DT model and lateral transhipment option helps beneficiaries to obtain relief items faster and with higher service level.  相似文献   
4.
This paper introduces the vehicle routing problem with soft time windows (VRPSTW) in which problem definition differs from ones previously defined in literature. Branch-and-price approach is employed, resulting in a set partitioning master problem and its new subproblem. Novel techniques are consequently developed to solve this new subproblem. Experimental results report the comparisons of these solution techniques under the branch-and-price framework. The VRPSTW solutions have further been compared to the state-of-the-art literature, signifying the superiority of the VRPSTW on this issue.  相似文献   
5.
China launched the Shanghai Free Trade Zone (FTZ) Program on September 29, 2013 in a bid to reduce administrative interventions, ease restrictions on investments, further open up its financial system, and internationalize its currency to booster shipping, logistics, and commerce. This article aims to present a background of the Shanghai FTZ and some reflections on it. China’s economic reconstruction has made a major impact on its port cities. Competitions between ports are gradually evolving into competitions between supply chains, with ports no longer considered as isolated links in the transport chain but rather as integral links in the supply chain. Ports are transitioning into fourth-generation ports with the establishment of logistics and value-added activities, which are developed in conjunction with local industrial and service businesses. In this trend, China’s port cities can provide a wide range of value-added services and become centers of commodity flow, capital flow, and information flow. Specifically, the combined effects of driving the development of peripheral industries and actively coordinating the activities of relevant parties help regulate the operations of the entire supply chain to obtain potential value-added benefits. The implementation of the Shanghai FTZ will not only stimulate trade but will also bring increased shipping and finance opportunities to the city. With free trade as the new direction and focus of the country’s economic initiatives, the Shanghai FTZ will hopefully lay the groundwork for a new round of reforms and restructuring of the Chinese economy.  相似文献   
6.
This article studies a container drayage problem with flexible orders defined by using requiring and releasing attributes as a unified formulation of various order types. A determined-activities-on-vertex (DAOV) graph introduces a temporary vertex set to formulate different truck statuses. The problem is formulated as a mixed-integer nonlinear programming model based on the DAOV graph. Four strategies including a window partition based (WPB) strategy are presented and evaluated extensively to solve the problem. Results indicate that the WPB method could solve the problem effectively and efficiently. Furthermore, this method is robust considering the operating time biases compared to other algorithms.  相似文献   
7.
包西高速铁路作为我国"八纵八横"高速铁路通道中重要的纵向通道之一,建成后呼包鄂城市群和关中平原城市群将实现有效连接。鄂尔多斯市为典型的"一城双核"城市,包西高速铁路的引入将对地区客运布局产生较大影响,根据鄂尔多斯地区城市及铁路现状、城市总体规划及交通规划,结合地区客运量及特点,提出地区内包西高速铁路引入方案及车站设置方案,确定合理的引入及客站布点,研究地区内高速铁路客站布局,结合地区客流特点,确定高速铁路车站分工;合理确定引入地区线、站位方案将有助于完善鄂尔多斯铁路枢纽的客运铁路布局,有助于完善鄂尔多斯地区高速铁路网络,提升呼包鄂城市群的辐射效应,促进城市建设和经济发展。  相似文献   
8.
High-speed rail has developed both nationally and internationally in Europe as a successful alternative to both air and road over distances of 400–600 km. Inter-city traffic, especially between the major metropolitan areas in North-west Europe has benefitted greatly from the investment in this network. This paper explores two issues: the impact on the intermediate areas between these major metropolitan areas and the creation of potential cross-border inter-regional services. The evidence shows how both levels of service and potential economic impacts have been much less pronounced in these intermediate areas. Such areas have been affected both by a failure to see greatly improved direct access to major cities other than within their own countries and a lack of new cross-border inter-regional services. The paper argues that the creation of the high-speed rail TEN-T has not met the primary objectives of reducing regional disparities in accessibility or reducing the effect of national borders on regional integration. To achieve this requires not just infrastructure provision but an appropriate regulatory framework for service provision and accompanying measures at the local level.  相似文献   
9.
This paper proposes a new strategic planning model for high-speed rail ventures. It is a mixed-integer optimization model that applies to a given line and focuses on two key strategic decisions: station location and fleet composition. Our purpose is to improve on previous station location models by including fleet composition decisions. In the new model, we additionally take into account in an approximate fashion the interrelationships between strategic and subsequent tactical decisions, regarding line planning, train scheduling and fleet assignment issues. The usefulness of the model is demonstrated for a case study involving a planned Lisbon-Oporto high-speed rail line.  相似文献   
10.
金安桥水电站左岸护岸边坡开挖爆破区环境复杂,紧挨将要拆除的下游围堰,在爆破时不能丝毫破坏其下游围堰。为了确保下游围堰、基坑抽水设备的安全,采用预裂爆破、孔间微差爆破、孔内微差爆破,选用较为合理的爆破参数控制爆破,顺利完成了左岸护岸边坡开挖爆破工作,为下游围堰的如期拆除创造了条件。  相似文献   
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