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61.
许婷 《水道港口》2010,31(4):260-265
依据最新的水文、泥沙实测资料进行了统计分析,为数模计算提供参数,然后建立多重嵌套潮流数学模型,计算正常天气下工程实施前、后的海域潮流场分布情况,并在年均含沙量的风浪条件作用下计算港池航道常年回淤情况,对港池航道建成后的年淤积量进行预报,从潮流泥沙角度为登沙河港区建设提供了设计依据。计算结果表明,3个方案实施后对周边水域影响均较小,港区虽有环流但强度较低,停泊区域流速很小。外航道区域方案一横流明显小于其他2个方案。3个方案实施后,港池航道年平均淤强介于0.08~0.12 m,淤积很轻。因此,该工程是可行的。  相似文献   
62.
为研究船舶在混合水域内船舶靠离泊作业对其航道通航效率的影响,以交通波理论为基础,结合船舶交通流特 性,建立了混合水域船舶交通流波动模型,进而解释船舶靠离泊作业时船舶交通流的集聚和消散过程,根据船舶交通量、 航速、船舶流密度和靠离泊作业时间,建立混合水域干扰影响范围与时间计算模型。以福姜沙南水道为例进行模型验证, 进行安全条件下的混合水域船舶通航效率量化研究。  相似文献   
63.
随着港口投资结构多元化、航运企业向综合物流商转变,“港航合一”成为航运业未来的发展趋势.在此背景下,研究航运企业投资对码头的影响能够为码头健康发展提供一定的理论依据.本文先采用三阶段DEA模型对我国沿海集装箱码头2008–2012 年间的运营效率进行测度,其次依据投资结构将我国沿海62 个集装箱码头进行分组,最后重点分析投资结构与码头运营效率之间的关系.研究结果显示,有航运企业投资的码头运营效率普遍高于无航运企业投资的码头,两组码头的纯技术效率相差较小,而规模效率相差较大.航运企业参与码头建设经营可以实现自有船舶挂靠自有码头,提升码头设施的利用率,从而提升码头的规模效率,有利于码头的健康发展.  相似文献   
64.
Navigation safety on coastal waters is an extremely important issue. Fatigue is an important factor threatening navigation safety. Considering that the vessel type is an oil tanker, such a threat is not posed only to the crew but also to the environment. Most of the tankers navigating coastal waters are in the small tanker category. Therefore, this study examined the working and resting hours of the deck officers in the oil tankers navigating coastal waters. The study utilized the ISF Watchkeeper 3 program for assessing and interpreting the working periods. The study reached the conclusion that the first and second officers in particular are working under unsuitable conditions. To improve the working conditions of the deck officers, effects of additional cargo officer on board was investigated. This study is in quality of recommendation. The study elucidated that the cargo officer practice determines the working and resting hours of deck officers, in the work on the oil tankers, and compliance with the related conventions.  相似文献   
65.
Participation (e.g., stakeholder involvement) has become a central concept in the practice of environmental and coastal zone management. Research has shown that the integration of participation in coastal zone management has positive ecological and social outcomes. In the literature, however, participation is often reported in an unstructured and uncritical manner. Therefore, to find out whether and how there is a useful way to structure and characterize the way the coastal zone management literature deals with participation, we have conducted a literature review. The review was conducted and the literature structured through three central dimensions of participation, namely: power, knowledge, and (visions of) nature. The article concludes that this structured approach to participation enables us to study more systematically the role of participation and might facilitate the governance and learning processes of coastal networks.  相似文献   
66.
Relative sea-level rise will affect vulnerable coastal communities globally. Quantifying this effect on the coastal environment and infrastructure provides critical information that enables coastal managers to develop sustainable mitigation and adaptation measures. Modeling applications have enabled the past, present, and future trends in shoreline morphology to be investigated in detail. Predictive numerical models depend largely on the reliability of the input data. This article reports on using the Soft Cliff and Platform Erosion (SCAPE) numerical model to simulate future shoreline evolution trend in the central Accra coast in Ghana. The model input parameters include historic shoreline recession rates, wave data, tidal data, bathymetry, beach volume, beach topography, historic relative sea-level rise rates, and the shoreline orientation. The data fed the SCAPE numerical model which simulated the emergence of soft rock shore profiles over timescale of decades to centuries, to project future positions of the central Accra shoreline for the next 100 years under different scenarios of climate change. Simulated future shoreline positions overlaid on a 2005 orthophoto map of Accra enabled vulnerable areas and infrastructure at risk to be identified. It emerged that a highly populated community in central Accra will be inundated by 2065, while the Rivera beach resort will be eroded from 2035. A natural fish landing site in Osu (suburb in Accra) will be lost from 2045. The study has demonstrated that considerable ecological, economic, social, and national losses should be expected within the next century. Shoreline change management options should be explored to help mitigate the expected impact of the sea-level rise.  相似文献   
67.
Site selection is a key factor in any aquaculture operation, affecting both success and sustainability. Moreover, it can solve conflicts between different coastal activities, making a rational use of the coastal space. Geographical information systems (GIS) have become of increased significance for environmental planning and assessment mainly because of the need to compare a great number of spatially related data, and because it can be used to couple these spatial data with their attributes and overlay them. This study used GIS and related technology to build a spatial database using those criteria which were considered to have any influence in integrating marine fish-cage culture within the tourism industry in Tenerife. Criteria were grouped in three submodels (distance to beaches, nautical sports, and viewshed), which were combined to generate a final output showing the most suitable areas for cage culture development in coexistence with tourism. Most areas of the coastline of Tenerife were identified as being suitable (56%) or very suitable (46%), suggesting that marine cage aquaculture could be developed on the island in coexistence with the well-established tourism industry.  相似文献   
68.
Fifty-five percent of Georgia's developed coastline has been armored with various types of erosion protection devices. This article is about beach improvement projects at Jekyll Island that would operate under (a) a nourishment policy or (b) a retreat policy. Benefits are calculated from an intensive, on-site survey of beach visitors and the costs are calculated from observable sources. Two financing methods are considered: general revenue and user fee financing. The analyses imply recommending beach improvement as an effective policy within the considered time frame.  相似文献   
69.
This article explores how a fresh approach to integrated coastal zone management (ICZM) in Ireland might be forged through the identification of a number of key innovative cross-sectoral professional initiatives and interdisciplinary academic thinking in this sector. It includes three interlinked research themes that assess existing cross-sectoral data management issues (to include an assessment of readiness for the INSPIRE and compliance with the Re-use of Public Sector Information European Union Directives), the degree of cross-pollination between the various sectors involved in managing the Irish Coastal Zone (to identify the need (or otherwise) for capacity- building to encourage cross-fertilization of ideas, skills, and knowledge exchange), and cross-professional competencies (to assess the desire/need (if any) for those working in coastal zone management to add to their existing competencies through continuous professional development or lifelong learning opportunities). Indeed, the specific competencies for coastal practitioners are identified here and these further illustrate the need for professional recognition of the role, responsibilities, and therefore the requirement for an appropriately qualified “Coastal Manager” professional, one that is seen not merely as a nicety but rather a necessity—a core enabler in any future innovative and integrative management approach.  相似文献   
70.
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