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31.
对于地理本体的研究是在考虑地理信息自身特殊性的基础上,把本体在信息科学中的含义移植到地理信息科学中,实现对空间信息语义的丰富。目前没有一个标准的地理本体构造方法。本文针对当前地理本体构建方法的不足,提出了一种新的地理本体构建方法。该方法强调需求分析的重要性,采用螺旋式上升的构建过程,构建了海运领域地理本体,实现了海运地理信息的语义共享。  相似文献   
32.
This paper investigates the sources of goods being shipped through the Arctic passages, and trade generated in the Arc- tic, including oil and gas exploitation. Furthermore, it assesses the present situation for maritime cargo shipped from the Far East to Northwestern Europe and North America. Two main types of cargo are predicted to pass through the Arctic passages in the future. First, about 10 million t of liquefied natural gas will be delivered from Russia and the Nordic Arctic to the Far East by 2030. Second, there will be two-way trade flow of containerized cargo from the Far East to Europe and the United States through the North- east, Central and Northwest Passages. This will relieve pressure on present routes from the Far East to Northwestern Europe and North America. If Arctic navigation is technically possible in all seasons and shipping costs fall to those of ordinary ships, then assuming an equal share of shipping volume with the traditional canal routes, the maximum container freight passing through the Arctic passages by 2030 will be approximately 17.43 million TEUs (Twenty-foot Equivalent Units) per year, which is 85% of the volume transported on traditional canal routes in 2011. We conclude that there will be large-scale gas transportation through the Northeast Passage in the near future, and transit shipping across the Arctic will focus more on container transportation. The differences in shipping costs between Arctic routes and traditional canal routes are also compared.  相似文献   
33.
利用2002—2013年的海冰密集度数据对北极东北航道通航关键区域——维利基茨基海峡的海冰分布特征和通航性进行了分析研究。结果表明,近十年来从8月中下旬到10月中旬海峡海面状况适合船舶航行;海冰冰情年际变化很大,对维利基茨基海峡通航天数有明显的影响;海峡每年可通航时间基本在40 d以上,其开通时间年际变化较大,从7—9月不等,而结束时间相对集中在10月份。  相似文献   
34.
The rapid decrease in Arctic sea ice cover and thickness not only has a linkage with extreme weather in the midlatitudes but also brings more opportunities for Arctic shipping routes and polar resource exploration, both of which motivate us to further understand causes of sea-ice variations and to obtain more accurate estimates of seaice cover in the future. Here, a novel data-driven method, the causal effect networks algorithm, is applied to identify the direct precursors of September sea-ice extent covering the Northern Sea Route and Transpolar Sea Route at different lead times so that statistical models can be constructed for sea-ice prediction. The whole study area was also divided into two parts: the northern region covered by multiyear ice and the southern region covered by seasonal ice. The forecast models of September sea-ice extent in the whole study area(TSIE) and southern region(SSIE) at lead times of 1–4 months can explain over 65% and 79% of the variances, respectively,but the forecast skill of sea-ice extent in the northern region(NSIE) is limited at a lead time of 1 month. At lead times of 1–4 months, local sea-ice concentration and sea-ice thickness have a larger influence on September TSIE and SSIE than other teleconnection factors. When the lead time is more than 4 months, the surface meridional wind anomaly from northern Europe in the preceding autumn or early winter is dominant for September TSIE variations but is comparable to thermodynamic factors for NSIE and SSIE. We suggest that this study provides a complementary approach for predicting regional sea ice and is helpful in evaluating and improving climate models.  相似文献   
35.
The growth of peripheral ports to dominant hubs has been well documented in North America and Europe,and has led to the elaboration of several theoretical models.However,although changes in containerization growth have been taking place in the South and East Asia in recent years,particularly in China,only a few studies have fo-cused on this region.The Pearl(Zhujiang) River Delta(PRD) has a typical port system with hub and peripheral ports,and provides an excellent case for studying the Peripheral Challenge.This paper introduces the theoretical evidence of the Hayuth model and analyzes the evolution of the container port system in the PRD with five phases:1) phase I:preconditions for change and phase II:initial container port development in the 1970s and early 1980s;2) phase III:diffusion,consolidation,and port concentration in the middle and late 1980s;3) phase IV:the load center in the 1990s;and(4) phase V:the Peripheral Challenge since the late 1990s.The results illustrate that the Shenzhen port presents mounting challenges to the Hong Kong port,descending from a transshipment hub of China to a regional load center of Southeast China.Furthermore,this paper explores five points that have led to the evolution of the port system in the PRD:1) competition in the regional port systems;2) different interested parties;3) shift of investment strategies of in-ternational terminal operators;4) integration of shipping networks and reorganization of carriers;and 5) cost-based competition.  相似文献   
36.
In order to expand registered fleet tonnage and strengthen ship management, China began to introduce a special tax-free ship registration (STFSR) policy in July 2007. However, more than eight years following its implementation, the policy ended in complete failure at the end of 2015. This paper comprehensively evaluates the main content and implementation process of the Chinese STFSR policy, analyzes the effects of the policy, and summarizes the concrete reasons for the policy's failure and lessons to be learnt. A new governance framework is being designed and future directions are being developed to explore how the government can implement a successful ship registry policy. This research is intended to provide new ideas and information to the Chinese shipping industry's policymakers and stakeholders in order to handle the “flagging out” problem, thereby mitigating the current adverse situation of ship flagging overseas while strengthening the management of ship operation.  相似文献   
37.
为面向长江航运开展可视化气象保障服务,本文设计了天气通航等级来表征天气对航运的影响,给出了应用沿江气象实况监测、网格预报、服务预警信息,计算航运调度管理和船舶行程规划两种服务场景下天气通航等级的具体算法和应用天气通航等级开展智能航运气象服务的方法,介绍了基于天气通航等级的长江航运气象预报预警服务系统的总体设计、主要产品、系统功能和主要特点,并结合航运气象服务发展,探讨了系统未来的改进方向。  相似文献   
38.
青岛国际航运中心构想   总被引:2,自引:0,他引:2  
当今世界海洋运输特别是集装箱运输迅猛发展,急需海港同步发展。青岛具有优良港口资源和地理区位优势及广阔丰富的经济腹地,可持续发展为国际航运中心。  相似文献   
39.
The Paris Agreement, which entered into force in 2016, sets the ambitious climate change mitigation goal of limiting the global temperature increase to below 2°C and ideally 1.5°C. This puts a severe constraint on the remaining global GHG emissions budget. While international shipping is also a contributor to anthropogenic GHG emissions, and CO2 in particular, it is not included in the Paris Agreement. This article discusses how a share of a global CO2 budget over the twenty-first century could be apportioned to international shipping, and, using a range of future trade scenarios, explores the requisite cuts to the CO2 intensity of shipping. The results demonstrate that, under a wide range of assumptions, existing short-term levers of efficiency must be urgently exploited to achieve mitigation commensurate with that required from the rest of the economy, with virtually full decarbonization of international shipping required as early as before mid-century.

Key policy insights

  • Regulatory action is key to ensuring the international shipping sector’s long-term sustainability.

  • For the shipping industry to deliver mitigation in line with the Paris Agreement, virtually full decarbonization needs to be achieved.

  • In the near term, immediate and rapid exploitation of available mitigation measures is of critical importance.

  • Any delay in the transition will increase the risk of stranded assets, or diminish the chances of meeting the Paris Agreement's temperature commitments.

  相似文献   
40.
Brian Slack 《GeoJournal》1999,48(1):9-14
This paper describes the development of containerisation in one of the most important theatres of maritime trade, the North Atlantic. As the original hearth of containerisation, it has been an area of experimentation and evolution for a technology that has burst around the world. Although over the last decade the Atlantic has been superceded by the Pacific Ocean as the major market focus for containers, it still is an important market arena. The emergence of global shipping networks is tending to favour the Atlantic once again. The paper provides an analysis of these recent developments. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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