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91.
92.
Po-Hsing Tseng 《Maritime Policy and Management》2018,45(4):422-438
As Arctic sea ice shrinks due to global warming, the Northern Sea Route (NSR) and the Northwest Passage (NWP) offer a substantial reduction in shipping distance between Asia and the European and North American continents, respectively, when compared to conventional routes through the Suez and Panama Canals. However, Arctic shipping routes have many problems associated with their use. The main objective of this paper is to identify the key criteria that influence the decisions of shipping operators with respect to using Arctic shipping routes. A multi-criteria decision-making methodology, the Fuzzy Analytic Hierarchy Process, is applied to rank four potential categories of criteria (‘economic’, ‘technical’, ‘political’ and ‘safety’ factors) and their sub-criteria.
The results of the analysis suggest that, on aggregate, ‘economic’ is the most important category of influential factors, followed by ‘safety’, ‘technical’ and ‘political’ factors. The paper concludes, however, that the most influential specific sub-criteria relate to risks that lie mainly within the ‘safety’ and ‘political’ domains and that, especially in combination, these overwhelm the importance which is attached to ‘economic’ factors such as reduced fuel use. Finally, the implications of these findings for the future development of Arctic shipping are addressed at a strategic level. 相似文献
93.
Iris Hui 《Coastal management》2017,45(3):179-198
This paper examines the California Coastal Commission's permitting process. Using several text mining techniques, including web scraping, information extraction, and supervised classification, I demonstrate how to retrieve empirical data from unstructured texts, namely public meeting agendas and staff reports. Contrary to the concern that the Commission routinely delays or rejects permitting requests, the data reveal that outright rejection of permit applications is rare. On average, eight of ten applications were approved. Single-family homes and commercial development projects were approved about 80% of the time; the rates were about 70% for seawalls and retaining walls, and 60% for land-use changes. Most applications were processed swiftly, with a median application length of 3 months. The agency's influence comes primarily from negotiating each application. Qualitative study of 50 cases pertaining to single-family home construction reveals that the agency adopts a “managed development” approach, that is, allowing development but scrupulously managing various aspects of development. These case studies illustrate how the agency interprets the broad, abstract state laws and translates the mandates into enforceable actions as permitting conditions. In areas where the state mandates conflict, particularly over development in receding shorelines, the agency has the largest leverage in creating and implementing its preferred policies. The text mining techniques demonstrated in this paper can be applied to study any governmental agency. These techniques help to extract information from a massive volume of papers and organize them into a database for analyses. The empirical data extracted from texts can significantly increase bureaucratic transparency. 相似文献
94.
南汇边滩位于长江口和杭州湾的交汇地带,受长江口和杭州湾北岸两股潮流的控制,近年来由于低潮滩促淤围垦工程导致其水流和泥沙运移、沉积和地貌发生了显著的变化。根据2006—2008年南汇边滩测图及2007年11月—2008年11月每个季度的9个断面测量资料,结合区域内的泥沙沉积特征,探讨南汇边滩对周边涉水围垦工程和流域来水来沙变异做出适应性地貌耦合过程之后的近期冲淤演变规律,着重探讨季节性冲淤特征。结果表明:年度上南汇东滩以淤长为主,南汇南滩以冲刷为主。不同季节南汇边滩冲淤变化过程存在很大差异:平面上,南汇边滩等深线夏、冬季以淤进为主,春、秋季以蚀退为主;垂向上,南汇东滩断面呈春夏秋冲淤交替、冬季淤积的态势,南汇嘴断面呈秋季冲刷、冬夏季淤积的态势,而位于南汇南滩的断面则呈秋冬季冲刷、春夏季淤积态势。南汇东滩沉积物粒径总体上较细,东滩与南滩交汇处的南汇嘴附近中值粒径相对较粗,南汇南滩浅滩沉积物颗粒中值粒径最粗。 相似文献
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97.
AHP在公路主枢纽站场
总体布局规划中的应用* 总被引:13,自引:1,他引:13
为使我国公路网“三主一支持”的规划建设建立在易操作,可定量化的基础上,利用简便
实用的层次分析法建立了公路主枢纽站场总体布局方案比选模型,进而对定量、定性判断矩阵分
别提出了相应的分析构成方法,并给出了比选模型的计算过程及应用实例。经实践证明,该方法
是可行的。 相似文献
98.
99.
陈进东 《广东交通职业技术学院学报》2014,(2):33-34
桥梁无支架施工作为一种能缩短施工时间,减少桥梁附属工程工作量的施工方法,已经在公路桥梁施工中大量运用。文中从实例出发,对穿钢棒的结构、受力计算、穿钢棒法施工盖梁工艺等做了详细分析。 相似文献
100.
从试验模型、试验材料、试验装置及测试内容等方面制定了工程弃渣型坡面泥石流试验方案,拟定了模型试验过程,降雨历时16-18 h,其中0~13h属于前期降雨阶段,降雨强度控制在6.8 mm/( 10 min),分4次完成,每次降1h,停2h;13h以后属于短历时强降雨阶段,降雨强度控制在16.7 mm/(10 min);分... 相似文献