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321.
通过对直立式防波堤堤头的局部波浪整体物理模型试验,发现存在特定条件下的波浪涡漩及其对水工建筑物结构稳定的影响。分析涡漩产生的原因和影响因素,并从设计角度提出应对涡漩的工程措施,对相关水工建筑物设计有一定参考价值。同时,也说明水运工程中采用物理模型试验手段验证和优化设计方案的重要性。  相似文献   
322.
Livelihood diversification can increase the number of activities generating income and is often adopted as a means to reduce vulnerability to risk and provide a pathway out of poverty. Previous empirical studies, however, have found that this diversification carries no guarantee of success. This study examines the impacts of investments in conservation-based enterprises and micro-credit interventions implemented in coastal Tanzania. Project beneficiaries (n = 178) and non-beneficiaries (n = 117) from seventeen communities surrounding Saadani National Park and the Menai Bay Conservation area were surveyed in 2013, to gather quantitative and qualitative data on a suite of parameters including the number of livelihood activities, total annual income, and engagement in extractive activities. We found that the beneficiaries reported an average of 2.15 livelihoods, which was significantly higher than the 1.44 average reported by the non-beneficiaries. The beneficiaries also had significantly higher mean annual incomes than the non-beneficiaries as the former reported an annual mean income of US $2,076 while the latter reported US $646. The research found a complex relationship between occupational diversity and people's interactions with the environment and it is clear that livelihood diversification is not a blanket solution to reducing pressure on coastal resources. Another important finding from the research is that there are distinct differences between types of livelihood interventions and it is crucial to be clear about the goal of a livelihoods intervention. If the goal is diversifying livelihoods and strengthening resilience, then livelihoods that provide a small and steady income for many entrepreneurs may be enough. However, if the goal is to bring people out of a poverty trap, then it makes more sense to invest in livelihoods that bring in a higher income, even if that means reaching fewer beneficiaries.  相似文献   
323.
海岸地区的长周期地貌演变关系到了人类对海岸带资源的合理开发、保护及可持续利用。研究者不断改进和提高了海岸地区长周期地貌模型的适用性和可靠性。文章从发展概况、时空尺度、计算原理、信息约减技术以及模型应用等方面简述了海岸地区长周期地貌模型的研究进展,并认为模型的理论、技术还可进一步提高,模型的应用范围还可拓展到更大尺度。  相似文献   
324.
The Spanish Strategy for Coastal Sustainability (SCS) was an initiative aimed at implementing coastal interventions under the principles of Integrated Coastal Zone Management (ICZM) and improving the state of the coast at the Spanish national level. The SCS, promoted by the Spanish Ministry of the Environment, started as a broad national strategy in 2005 and was finally delivered as a coastal planning instrument at the regional level in late 2007, designed to address coastal policies within the Spanish maritime–terrestrial public domain (MTPD). The initiative was triggered by the increasing pressure on the coastal zone and its preparation was supported by different European initiatives, first of all the European Recommendation on ICZM (413/2002/EC), while taking into consideration the future requirements of the Mediterranean Protocol on ICZM of the Barcelona Convention, signed in February 2008. Technically, the preparation of the SCS included four steps: (i) a Stakeholder Identification and Engagement process, including a stocktaking of the laws and regulations, (ii) the design of a broad Strategic Framework for the Spanish coastal zone, including a set of specific objectives and the instruments for its implementation, (iii) the signature of cooperation agreements for ICZM between the central government and the regions, and (iv) a detailed Technical Diagnosis at the local scale, designed to address future coastal interventions in the maritime–terrestrial public domain and its areas of influence. This article aims to: (i) illustrate the triggering factors of the SCS, including the Spanish coastal issues, the administrative framework at the national level, and the European and international policies addressing coastal management and (ii) illustrate the approaches and methodologies used for the preparation of the SCS, reporting the most relevant quantitative results. The article concludes that the SCS gave a strong contribution in the construction of a base of knowledge for the coastal zone and to improve coastal management practices. Despite this, complex distributions of competences still undermine the implementation of strategic interventions. In this context, the future ratification of the ICZM Protocol of the Barcelona Convention represents an opportunity to use the SCS process results and improve coastal management practices and the state of the coast.  相似文献   
325.
326.
Howard Ris 《Coastal management》2013,41(3-4):299-311
Abstract

This paper concerns the limitations on integrating visual management into the coastal zone planning process as exemplified by the Commonwealth of Massachusetts, a state with a strong tradition of “home rule”; and a CZM implementation program based on a “networking”; of existing state authorities. The implications of the Massachusetts experience are that: (a) management of esthetic resources at the state level continues to be much less of a priority than management of ecological resources such as wetlands or floodplains; (b) visual management has yet to engender a strongly supportive constituency beyond that concerned with historic preservation; (c) project review focusing on visual impacts may be a more appropriate activity for local rather than state government; and (d) the technical aspects of visual management or impact assessment are far more advanced than their political acceptability. Political realities, together with the decision that implementation of the program should be based on a networking of existing authorities, thus determined the degree to which visual management could be incorporated into the state's program. As a result, the program's principal instruments of visual management became a strengthening of existing programs such as Wild and Scenic Rivers, reliance on wetland protection statutes to indirectly protect natural scenic values, and the use of the federal consistency provisions of the Coastal Zone Management Act to foster focused growth patterns through provision of publicly funded infrastructures. Esthetically oriented project review, with the exception of potential impacts on historic sites, was left to the discretion of local government, and a technical assistance program was created to provide funding or professional skills to communities interested in developing their own esthetic controls or design review processes. Maine, Rhode Island, and other New England states have followed a similar course.  相似文献   
327.
Abstract

The physical characteristics of Korea have had a profound impact on the uses of the coastal zone that have, in turn, been determined by and reinforced the nation's economic development strategy. While coastal zone management in many developed economies is more heavily oriented toward environmental protection and the resolution of user conflicts, policies for coastal zone management in Korea have emphasized the role of coastal space and other resources for economic development and industrial needs. Increasing demand for land reclamation to provide ever‐increasing industrial sites and human settlements, traditional and future needs of the fishery, and concern for the environment have led to a vast array of competition and, finally, often to conflicts. The basic pattern of coastal zone use in Korea has changed from the linear expansion of coastal zone to integrated coastal uses. An increased number of critical coastal zone issues and interactions was reflected in the creation of new governance that dealt with coastal zone resources and environment.  相似文献   
328.
In recent years, an increase in the size of the container ships could be observed. The question is how these larger ships will influence the total generalised costs from a port of loading to a destination in the European hinterland. The second question is whether a scale increase of the container ships on other loops, such as a loop from the United States to Europe, has the same impact on the generalised chain costs as on the loop from Asia to Europe. A derived question is which element of the total chain has the highest importance, and whether this balance varies as the ship size changes. In this article, a model is developed that allows answering the above research questions. The model is designed to simulate the cost of a complete loop of a container ship and of a chain that uses that same loop. For the chain cost simulation, the maritime part is determined by the loop. From the ports of loading and unloading, the port container handling and the hinterland transportation costs are also integrated. The model also allows calculating the total chain cost from a point of origin (either a hinterland region or a port) to a destination point (also a port or a hinterland region). An actual container loop of a container shipping company can be introduced in the model. An application is made to two existing container loops, namely from Asia respectively the United States to Europe. It turns out that changing ship does indeed lead to economies of scale, but also that the impact is larger on the Asia–Europe connection than on the US–Europe connection. Furthermore, the maritime component has the biggest share in the total chain cost, but as ship size increases, the shares start getting closer to each other. This research contributes to the existing literature in two ways. First of all, it quantifies the impact of the scale increase of container ships throughout the total chain. Second, this is done from a bottom-up engineering modelling approach.  相似文献   
329.
Abstract

Despite a concentration of container traffic in the southeast of the UK over the last few decades, regional ports are attempting new development strategies to capture or retain specific traffic segments. These include intra-European short-sea traffic and a potentially increasing feeder market. These trends are reflected in the movement of different container types, which result in a number of planning challenges related to changing infrastructural and operational requirements. This paper uses highly disaggregated data on container type movements to address three issues that can inform these planning challenges. First, the imbalance of trade resulting in empty container repositioning; second, the requirement for gauge-cleared rail routes to cater for the increasing proportion of high-cube containers; and third, the specialisation of European short-sea traffic at secondary UK ports. The results reveal the disproportionate repositioning of empty containers at Scottish ports and the importance of 45?ft, high-cube and pallet-wide containers at regional ports, highlighting their focus on intra-European short-sea traffic and raising difficulties relating to their lower quality of landside infrastructure (particularly rail) in comparison to the large south-eastern ports. The potential repercussions on hinterland infrastructure development raise questions about both public and private sector responses to regional port development.  相似文献   
330.
港口企业信息化与业务流程重组   总被引:6,自引:0,他引:6  
段青 《港口装卸》2003,(6):28-30
现代信息技术在世界各个港口被广泛地应用 ,对港口企业的发展发挥着重要的作用。但是 ,传统的港口业务流程与信息技术不适应 ,不能有效地利用信息技术带来的种种便利 ,进行业务流程重组成了当务之急  相似文献   
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