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181.
For over 5000 years, humans have successfully harnessed the power of wind to transport people and goods across the world's oceans. This research expands on previous studies of the unique Flettner rotor propulsion system and the demonstrable success in reducing fuel consumption and carbon dioxide (CO2) emissions. Recent examples such as Enercon's E-ship 1 have proven seaworthy and economically viable along major shipping routes. The remote Pacific island countries (PICS), however, have the unique characteristics of retaining a remarkable seafaring heritage while remaining on the periphery of global commerce. With data obtained from a field study of Fiji's domestic shipping, this research analyzes the potential for implementing Flettner rotor systems to achieve more economically viable alternatives to the current situation. The findings show that with an incremental approach and the addition of a government fuel savings incentive, the Government Shipping Franchise Scheme (GSFS) subsidies could be significantly lowered for Fiji's ten uneconomical shipping routes. Four scenarios of 5%, 10%, 15%, and 25% fuel savings contrast the baseline data on one extreme with a zero-emissions scenario on the other. The most likely fuel savings scenario of between 10% and 15% results in a 20-year government savings of between 348,042 and 522,063 U.S. dollars and a 20-year cumulative reduction in CO2 emissions of between 2931 and 4396 t. The paper concludes that Flettner rotors show promising results in reducing fuel consumption and CO2 emissions and recommends future studies in collaboration with the Fiji government to develop practical strategies of implementation.  相似文献   
182.
Seafarers make a critical contribution to civil society, but seafarers’ health has received comparatively little attention in the maritime world. China has the largest population of seafarers, and Chinese seafarers are working on board merchant ships flying different flags. The Maritime Labour Convention, 2006 entered into force in China in November 2016, and it has already generated significant impact in terms of policy, legislation and maritime practice. However, while seafarers’ treatment has been improved significantly in many countries, in particular in developed countries, Chinese seafarers are still facing some challenges relating to health issues, such as long working hours, insufficient nutrition, lack of recreation and poor mental health. Based on existing knowledge and scholarship available in the public domain, together with primary data collected in several phases of fieldwork, this paper critically examines a number of major issues relating to maritime health of Chinese seafarers.  相似文献   
183.
We analyze the problem of preventing biological invasions caused by ships transporting internationally traded goods between countries and continents. Specifically, we ask the following question: should a port manager have a small number of inspectors inspect arriving ships less stringently or should this manager have a large number of inspectors inspect the same ships more stringently? We use a simple queuing-theoretic framework and show that if decreasing the economic cost of regulation is very important then it makes more sense for the port manager to choose the less stringent inspection regime. In contrast, if reducing the damage from biological invasions is more salient then the port manager ought to pick the more stringent inspection regime.  相似文献   
184.
夏启繁  杜德斌 《地理研究》2022,41(7):1797-1813
能源安全与能源合作是“21世纪海上丝绸之路”建设的重点领域与核心内容,理清沿线能源贸易结构演化特征对明晰“能源海上丝绸之路”建设的方向与路径具有一定意义。论文基于2000—2018年沿线国家化石能源贸易数据及其对外经贸属性,借助贸易互补模型、复杂网络方法、GIS空间技术等手段,揭示了沿线能源贸易的产品结构、网络结构及空间格局演化特征,探讨了海上丝绸之路在中国能源对外贸易中的地位变动及互补特征。研究发现:① 沿线贸易规模近年扩大,贸易逆差明显。进口占全球的比例有所上升,出口占比整体下滑。② 原油、液化天然气和煤炭产品是主要贸易产品。发达国家多对技术要求较低的原始产品具有进口劣势,对加工制成品具有出口优势,发展中国家基本相反。③ 消费大国逐步取代出口大国成为石油贸易网络核心节点;资源赋存国家始终主导天然气贸易网络;出口大国与消费大国共同主导煤炭贸易网络。④ 石油贸易形成亚洲洲内“拱形”格局且不断夯实;天然气贸易呈亚洲“金三角”和地中海“四边棱形”结构并存格局;煤炭贸易呈跨洲“多拱”联系衰落、洲内贸易增强格局。⑤ 海上丝绸之路是中国重要的能源供给地与合作对象。中国与沿线国家在石油贸易领域互补水平较高但有所下滑,在天然气与煤炭贸易领域互补水平较低但逐步提高。  相似文献   
185.
于涛  陈相秒 《热带地理》2022,42(7):1180-1189
通过梳理和界定海洋命运共同体这一重要倡议的具体内涵与外延,发现南海在为国家间海洋争端友好协商和平解决创造范例,给区域蓝色伙伴关系建设提供经验,探索构建以规则为基础的区域安全新秩序3个方面肩负着特殊使命。具体到海南,其在南海海洋命运共同体构建中承担着空间、功能、角色3个方面的特殊定位。海南虽然面临内生性挑战和外部干扰因素的双重阻力,但通过合理的空间布局和创新性的产业规划,有望把自身先天具有的地缘优势、深化改革开放和建设自由贸易港赋予的制度创新和政策红利等转化为参与南海命运共同体建设的实际成效。  相似文献   
186.
秋季南极涛动异常对冬季中国南方降水的影响   总被引:2,自引:0,他引:2  
钱卓蕾 《大气科学》2014,38(1):190-200
本文针对秋季南极涛动(AAO)和冬季中国南方降水的关系作了研究,发现两者之间存在显著的反向年际变化关系。AAO正(负)异常年,副热带西风急流显著增强(减弱),欧洲西部槽、乌拉尔山高压脊和东亚沿岸大槽均偏强(偏弱),阿留申低压、南支槽和西太平洋副高偏弱(偏强),西南急流上的扰动不活跃(活跃),我国大部分地区出现异常偏北风(偏南风)和OLR弱正距平,导致南方降水偏少(偏多)。两半球存在东亚—南半球高纬地区和纵贯太平洋南北的两个遥相关型,海洋性大陆对流活动可能是秋季AAO影响南方冬季降水的一个机制。因此,秋季南极涛动的异常很可能对预测我国南方冬季降水有显著指示意义。  相似文献   
187.
Today the health of ocean is in danger as it was never before mainly due to man-made pollutions. Operational activities show regular occurrence of accidental and deliberate oil spill in European waters. Since the areas covered by oil spills are usually large, satellite remote sensing particularly Synthetic Aperture Radar represents an effective option for operational oil spill detection. This paper describes the development of a fully automated approach for oil spill detection from SAR. Total of 41 feature parameters extracted from each segmented dark spot for oil spill and ‘look-alike’ classification and ranked according to their importance. The classification algorithm is based on a two-stage processing that combines classification tree analysis and fuzzy logic. An initial evaluation of this methodology on a large dataset has been carried out and degree of agreement between results from proposed algorithm and human analyst was estimated between 85% and 93% respectively for ENVISAT and RADARSAT.  相似文献   
188.
The recent tightening of military budget constraints has called into question the feasibility of costly multilateral naval intervention used to combat maritime piracy off the eastern coast of Africa. Though past studies agree that the transformation of the Somali economy and government is crucial for a long-term solution to piracy in this part of the world, short to medium-run solutions are needed to bridge the gap. Such solutions should be fiscally sensible and serve as effective deterrents, as well as be applicable in addressing the problem of piracy and maritime armed robbery in other parts of the globe. This paper builds upon the foundations laid in Mejia et al. [12] and Mileski et al. [13] by examining the following question: given that a ship is engaged by pirates, what factors help shape the outcome of the confrontation? This study finds that observable action taken on the part of a ship's crew is extremely effective in decreasing the risk of a ship being successfully robbed or hijacked. There has yet (as of May 2014) to be a reported incident where pirates successfully hijacked a vessel that had a security team on board, and so though the effectiveness of security in this matter can be inferred, it cannot be empirically tested (the same is true – in this study's dataset – of the effect of onboard security on deterring robberies). This may provide some guidance for policymakers; if naval intervention is to be scaled back, the encouragement and oversight of shipping companies’ crew response procedures (and perhaps of onboard security measures) by international governments could pose a valid alternative.  相似文献   
189.
斯里兰卡是海上丝绸之路沿线重要的节点国家,其周边海域生态环境变化与经济发展、休闲生活和食品安全密切相关。利用2002—2017年的MODIS遥感反演产品对斯里兰卡岛周边海域、关键节点港口科伦坡的生态环境参数年际变化规律分别进行分析和2003—2012年的MERIS遥感反射率产品对保克海峡进行水体类型时空分析,结论如下:① 研究区内光合作用有效辐射高值出现在马纳尔湾,海域沿岸浮游植物生物量相对较高,与海表温度负相关,外海浮游植物生物量极低,与透明度负相关。② 科伦坡港附近水温(海表温度)、海面光照强度(光合作用有效辐射)、水体清洁度(海水透明度)、海洋食物网基础的浮游植物生物量(叶绿素浓度)和浮游植物净初级生产力最大值分别出现在4月、3月、3月、8月、7月,致灾因素重点关注8月潜在的赤潮。③ 保克海峡浑浊带的源头是印度的卡里梅尔角,由高韦里河携带大量泥沙造成。这有助于了解和认识高时空变化的保克海峡及斯里兰卡周边海域在不同时间-空间的海洋生态环境。  相似文献   
190.
基于遥感和GIS技术,利用Landsat影像目视解译提取2000和2015年海上丝绸之路大陆岸线数据,从整体、洲际尺度、国家尺度、热点区域和港口城市5个空间尺度分析大陆岸线位置变化特征.结果表明:(1)整体方面,2000年和2015年海上丝绸之路沿线地区岸线扩张和后退的比例(速度)分别约为8.21%(27 m·a–1)...  相似文献   
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