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1.
The world’s oceans and coasts are awash in a sea of politics. The marine environment is increasingly busy, changing, and a site of degradation, marginalization, injustice, contestation and conflict over declining resources and occupied spaces at local to global scales. Themes of political ecology, such as power and politics, narratives and knowledge, scale and history, environmental justice and equity, are thus salient issues to understand in ocean and coastal governance and management. This subject review examines research on these themes of political ecology in the ocean and coastal environment and reflects on how the insights gained might be applied to governance and management. Political ecology provides important insights into: the influence of power in ocean management and governance processes; the manner in which narratives, knowledge, and scale are used to legitimize and shape policies and management efforts; the effects of historical trajectories on present circumstances, options, and practices; and the nature of inequities and environmental injustices that can occur in the marine environment. Moreover, ocean and coastal researchers, practitioners, and decision makers ought to engage with the political processes and injustices occurring in the ocean. Moving from critical insights to constructive engagements will ensure that political ecology helps to plant seeds of hope in the Anthropocene ocean.  相似文献   

2.
张晓怀  陈业初  寇蔚 《机电设备》2007,24(11):29-33,13
诊断软件由于其诊断对象的复杂性和诊断策略的多样性,为设计模式的使用提供了较大空间.将设计模式引入船用机电设备故障红外智能诊断软件的开发,并具体讨论了一些常见的模式如Adapter、Bridge、Strategy和Observer等在软件各个模块和环节中的应用.实验证明,设计模式的使用,简化、明晰了软件的结构,加强了软件的通用性、稳定性和灵活性,提高了软件的可理解性和可维护性,并使得丰富红外诊断软件的接口和功能变得更为容易,进一步拓宽了软件的使用范围.  相似文献   

3.
Road transport imposes negative externalities on society. These externalities include environmental and road damage, accidents, congestion, and oil dependence. The cost of these externalities to society is in general not reflected in the current market prices in the road transport sector.An efficient mobility model for the future must take into account the true costs of transport and its regulatory framework will need to create incentives for people to make sustainable transport choices. This paper discusses the use of economic instruments to correct road transport externalities, but gives relatively more weight to the problem of carbon emissions from road transport, as this is particularly challenging, given its global and long-term nature.Economics offers two types of instruments for addressing the problem of transport externalities: command-and-control and incentive-based policies.Command-and-control policies are government regulations which force consumers and producers to change their behaviour. They are the most widely used policy instruments. Examples include vehicle emission and fuel standards in the US as well as driving or parking restrictions in Singapore. The implementation cost of these instruments to the government is small. Although from an economic perspective these policies often fail to achieve an efficient market outcome, the presence of political constraints often make them the preferred option, in terms of feasibility and effectiveness.Economic theory shows how policies, which affect consumption and production incentives, can be used to achieve the optimal outcome in the presence of externalities. Incentive-based policies function within a new or an altered market. We first examine incentive-based policies, which cap the aggregate amount of the externality, such as carbon emissions, by allocating permits or rights to the emitters. The emitters are then free to trade their permits amongst them. The permit allocation mechanism is important-although market efficiency would be satisfied by an auction, political influences usually favour a proportional allocation based on historic emissions. We discuss EU ETS as an example of a cap-and-trade system, however, no such policy for CO2 emissions in road transport has been implemented anywhere in the world to date.Fiscal instruments are, like command-and-control, widely used in road transport, because they are relatively cheap and simple to implement. They include the use of taxes and charges in order to bridge the gap between private and the social costs and, in principle, can lead to an efficient market solution. Registration, ownership, fuel, emissions, usage taxes, and parking and congestion charges have been implemented in many countries around the world. On the other side of the spectrum, subsidies can be given to those scrapping old cars and buying fuel-efficient vehicles. Some cities, such as London, have implemented congestion charges and many states in the United States have introduced high occupancy lanes. Other interesting possibilities include pay-as-you-drive insurance and other usage charges. However, the size and scope of taxes and subsidies are determined by governments, and because of their imperfect knowledge of the market the outcome is still likely to be inefficient.Governments have many effective economic instruments to create a sustainable road transport model. These instruments can be used separately or together, but their implementation will be necessary in the nearest future.  相似文献   

4.
中国修船业在国家改革开放的浪潮中,经历了三十多年的快速发展,如今已稳居世界修船大国的国际地位,而中国修船企业正在引领世界绿色修船科技的进步,也引起了国际修船业的高度关注.然而,在人类社会生态环境面临严峻挑战的当下,作为世界贸易和港口经济重要组成部分的修船产业,如何形成发展新格局,从生态层面推进绿色、低碳、数字"一体化"...  相似文献   

5.
双鱼岛作为离岸式城市综合开发类人工岛,岛上陆域高程是一个独立的系统,陆域高程的确定关系到规划、安全、护岸、景观、土方量和造价、防洪排涝、亲水性等。对人工岛填海造地期和使用期高程确定的主要因素进行论述,并整体介绍双鱼岛高程的变化趋势,对不同部位的高程确定进行分析,同时对工程安全性与景观的平衡、高程与上部规划的关系、高程与土方量及最优造价进行研究。研究成果可供类似工程的高程确定提供思路及参考。  相似文献   

6.
At the time of writing (2010), the world is witnessing the aftermath of the most severe financial sector meltdown in modern economic history caused by the real estate bubble in the United States. Its consequences on the real economy, especially in Europe, are yet to be fathomed, and this of course includes the longer-term impacts on international ocean transportation, ports and the distribution of global production.The economic recession has left the international shipping and port sectors with substantial overcapacity. This has resulted in drastic cost cutting measures on the one hand, and voluntary, often consensual, and coordinated reduction of supply on the other. These measures, together with a noticeable recovery in demand, are gradually leading again to improvement in prices charged by carriers and other transport service providers.In view of the country’s expanse; size of population; and regional inequalities, India’s dry ports (inland cargo consolidation and distribution centres) are seen by the government as a pivot of export-led growth and economic development (Haralambides & Gujar, 2011). Moreover, public and private sectors alike see the coordinated development of dry ports as the only way forward in terms of easing pressures at congested coastal ports, thus improving supply chain efficiency. In spite of this, dry port development and operations are still dominated by the public sector, under prices, capacity, land acquisition policies and other conditions that make private sector participation risky and comparatively unattractive. In order to rationalize dry port capacity and prices, this paper argues in favour of greater devolution through competition-enhancing Public-Private Partnerships (PPPs). The paper puts forward recommendations for the necessary legal, regulatory and general economic policy interventions based on international best practice, while keeping Indian specificities in the right perspective.  相似文献   

7.
Spatial pattern of the global shipping network and its hub-and-spoke system   总被引:2,自引:0,他引:2  
Port system is a research focus of transport geography, and most studies believe carriers are important factors in the development and concentration of the port system. Since the 1990s, carriers have played an important role in organizing the global shipping network and reorganizing the port system. But there isn’t a perfect method to evaluate carriers’ influence and the roles of each port in the maritime shipping networks. In this paper, we use the monthly schedule table of international carriers to describe and model the spatial pattern of the global shipping network and identify its hub-and-spoke system. The result shows that a hierarchical structure exists in the global shipping network. The North Hemisphere, especially the East Asia and the Southeast Asia, is a dominant region of the worldwide shipping network. East Asia, Southeast Asia, Northeast Europe, and East coast of the USA are the concentration regions of worldwide shipping lines. The ports of Hong Kong, Singapore, Shenzhen, Shanghai, and Kaohsiung etc have advanced capacity for maritime shipping and high potentials for being hub ports in the global shipping network. Today, the worldwide shipping network is transforming from the multi-port calling system to 44 regional hub-and-spoke systems. Meanwhile, the sub-networks with hub ports of Antwerp, Singapore, and Hong Kong have become the most important ones and dominate the whole global shipping network.  相似文献   

8.
基于200米级高扬程升船机固定壁厚塔柱结构形式,以混凝土用量一致为原则,拟定变壁厚塔柱结构形式。采用有限元软件ABAQUS,分别建立了固定壁厚和变壁厚两种塔柱结构模型,对塔柱结构的动力响应进行对比分析。结果表明:1)在自重荷载、风荷载和8度地震作用下,固定壁厚塔柱结构和变壁厚塔柱结构的顶部最大位移分别为38. 5、34. 7 cm,均满足规范限值。2) 3条地震波作用下,两种塔柱结构的顶部加速度比底部加速度都大,呈现加速度放大效应,放大2倍左右。3)筏形基础与塔柱结构交界面出现了压应力集中,筏形基础左右、中间部分及筒体内部区域出现了拉应力集中。塔柱截面和挡土墙交界处易发生应力集中。4)变壁厚塔柱结构的顶部最大位移,筏形基础的最大拉、压应力,截面最大等效应力,均比固定壁厚要小较多。变壁厚塔柱结构形式更优。  相似文献   

9.
The brackish Baltic Sea has been seen as particularly suitable for studies of food webs. Compared to fully marine ecosystems, it has low species diversity, which means fewer trophic linkages to analyse. The Baltic Sea is also one of the best-studied areas of the world, suggesting that most data requirements for food web models should be fulfilled. Nevertheless, the influence of physical and biological factors on trophic interactions and biogeochemical patterns varies spatially in the Baltic Sea, adding considerable complexity to food web studies. Food web structure and processes can be described and compared quantitatively between areas by estimating the flow of matter or energy through the organisms. Most such models have been based on carbon, though studies of complementary flows of other elements limiting production, such as nitrogen and phosphorus would be desirable. However, since ratios between carbon and other elements are used in calculating these flows, it is crucial, as a first step, to quantify the flows of carbon as accurately as possible.In this study, we used the EcopathII software (ver 3.1) to analyse models of carbon flow through the food webs in the three main areas of the Baltic Sea; the Baltic proper, Bothnian Sea and Bothnian Bay. A previously published study on carbon flow in the Baltic Sea [Elmgren, R. 1984. Trophic dynamics in the enclosed, brackish Baltic Sea. Rapp. P.-V. Reun. — Cons. Int. Explor. Mer. (183) 152–169.] was complemented with the data on respiration and flow to detritus [Wulff, F., Ulanowicz, R. 1989. A comparative anatomy of the Baltic Sea and Chesapeeake Bay ecosystems. In: F. Wulff, J.G. Field, K.H. Mann (Eds.), Flow Analysis of Marine Ecosystems: Theory and Practice. New York: Springer-Verlag.] in order to present complete mass balance models of carbon. The purpose of re-evaluating previous models with new analytic tools was to check how well their carbon flows balance, and to provide a basis for improved mass balance models using more recent data, including nutrients other than carbon.The resulting mass balance networks for the Baltic proper, Bothnian Sea and the Bothnian Bay were shown to deviate from steady state. There was an organic carbon surplus of 45, 25 and 18 g C m−2 year−1 in the pelagic zones of the Baltic proper, Bothnian Sea and Bothnian Bay, respectively. The Ecopath network analysis confirmed that the overall carbon flow was highest in the Baltic proper, somewhat lower in the Bothnian Sea and much lower in the Bothnian Bay. The only clear differences in food web structure between the basins was that the average trophic level was lower for demersal fish in the Bothnian Sea and higher for macrofauna in the Bothnian Bay, compared to the other basins. The analysis showed weakness in our current understanding in Baltic Sea food webs and highlighted areas where improvements could be made with more recent data.  相似文献   

10.
针对传统防护区运行安全管理以人工为主、信息利用低、动态评估预警缺失等问题,结合龙溪口航电枢纽防护区运行安全管理的主要问题和需求,以创新运行管理模式、强化信息互联共享、提升智能管控水平为目标,构建集数据在线辨识、涝情监控预测、安全实时诊断、风险动态评估、预警响应决策于一体的多层次系统结构,提出涝情实时监控、涝情风险评估、防洪堤安全分析与风险评估等核心功能模块的实现路径和技术要求。研究成果可为全面提升龙溪口航电枢纽防护区防灾减灾能力和安全保障水平提供技术支撑。  相似文献   

11.
浮式生产储卸油装置(Floating Production Storage and Offloading,FPSO)管路系统具有特殊性,即个别管路系统必须采用气体压力试验。由于该试验危险性较高,危及人身及财产安全,因此展开具体分析。通过实地考察、管路分析、爆炸分析、精确安全隔离距离计算、工艺编制等举措,达到船舶所有人、船舶检验机构及安全部门的验收标准要求。该研究可为其他海洋工程及船舶项目设计和建造提供经验借鉴。  相似文献   

12.
在船舶制造中,技术成熟度的评估意识薄弱且缺少信息化手段。通过确定评估指标、设定权重,建立船舶制造技术成熟度评估系统,由系统计算成熟度的得分和等级,从总体设计、建造工艺、船厂建造资源能力、船舶研制定型后等方面进行评估。该系统可减少返工带来的时间成本、人力成本,提高船舶制造技术成熟度评估的科学性、准确性、可靠性、灵活性及效率。  相似文献   

13.
黄彬 《水运工程》2016,(7):36-39
秀涂人工岛是以泉州湾内的鞋沙浅滩为依托,在鞋沙浅滩西、北、东侧建设围堰,在南侧建设码头岸壁,围成闭合区域后吹填前方水域的疏浚土而形成的。对秀涂人工岛的总体设计情况及关键技术进行总结分析,包括平面形状、平面布置及分期实施方案、围堰结构、码头结构、陆域形成等人工岛设计的主要方面,可供类似工程参考。  相似文献   

14.
范亚丽 《船舶工程》2021,43(2):136-142
半潜式支持平台的研发面临一系列技术难题,尤其是恶劣海洋环境对平台的影响。恶劣环境下,平台会出现严重的非线性载荷特性,严重时会危害平台安全,因此在研发设计阶段,有必要开展半潜式支持平台在恶劣海洋环境下的运动性能研究。针对我国自主开发设计的某型深水半潜式支持平台,基于模型试验方法开展恶劣海况下运动性能研究。在完成水平系泊系统和气隙、砰击载荷测试方案设计的基础上,开展试验研究,获得了平台固有周期、阻尼系数、恶劣海况下的运动响应以及气隙、砰击等非线性载荷。结果显示,在恶劣海况下,目标平台运动响应较大,不具备作业条件。平台多处气隙出现负值且发生较为显著的砰击现象,砰击次数及砰击压力均较大。结果为半潜式支持平台总体设计提供了有效的支撑数据。  相似文献   

15.
章建峰  杨祯  鲍陈磊  张艳军 《船舶工程》2015,37(S1):161-164
当今以风能、太阳能为代表的可再生能源,因其储量丰富、环境友好等特点,得到人们日益广泛的重视。基于可再生能源的分布式发电是可再生能源利用的一种主要方式,然而,由于可再生能源的间歇性,导致了分布式发电系统的稳定性、可靠性以及电能质量问题,在这种情况下,储能系统应运而生。本文介绍了蓄电池、超级电容、燃料电池以及飞轮等几种常见的储能技术,简要分析各自的工作原理,比较了它们之间的优缺点,并以蓄电池和超级电容为例,分析混合储能系统的构成方式,最后通过Buck/Boost双向变换器与直流母线相连接,给出了一系列适合于分布式发电系统的隔离型Buck/Boost双向变换器,并比较了它们之间的优缺点。  相似文献   

16.
李良雄 《水运工程》2014,(11):10-14
长江数字航道建设是一项综合性很强的信息化工程,涉及多项技术的融合和技术实现。介绍长江数字航道建设的主要框架和建设目标,从通信现状、监控技术发展、智能通行指挥及分段实施中技术发展4个方面对长江数字航道建设面临的问题进行分析研究。认为长江数字航道建设应优先解决信息孤岛、提升GIS平台建设质量、技术上实现动态跟踪、不断变革管理思路,并提出相应对策,对数字航道建设设计、施工及整体推进具有指导作用。  相似文献   

17.
During the period May 25–October 28, 2007, we collected data in face-to-face interviews on four sites in the North Carolina Research Reserve system. We subsequently conducted analyses on the effects of education, income, length of visitation, and frequency of visitation on visitor knowledge, perceptions, and attitudes regarding management. Visitors to the sites were well-educated, listed incomes above the state median, and were racially homogeneous. At the overall level, the majority (63%) knew who owned the sites, but only 43% correctly identified the managing agency. The majority also believed that overall conditions at the sites were stable, although those that had been visiting longer perceived conditions as deteriorating. Education was positively correlated with knowledge of ownership and management, and with support for additional rules and enforcement. Neither income, nor frequency of visitation showed any correlation with any of the dependent variables at the overall level. Some site-specific findings differed from the overall findings and varied from site to site. These differences were addressed individually.  相似文献   

18.
针对目前港口工程高桩梁板式码头钢筋建模困难、性价比低、难以满足出图要求,无法达到设计阶段基于钢筋模型的成果交付要求等问题,对设计阶段构件级钢筋模型创建、出图及计量、参数化设计、模型交付等进行研究。采用Revit软件及Revit API技术相结合的方法,提出参数化的钢筋模型创建、出图一体化技术,并将其应用至实际工程。结果表明,该技术能快速创建符合要求的钢筋模型及图纸,可为类似工程提供参考。  相似文献   

19.
张少华  刘慧敏 《世界海运》2002,25(6):41-42,49
阐述了最新研制开发的船舶自动化电站模拟器主要组成及功能原理。其基本功能是:操作控制的模拟功能,机组的安全保护功能,电站、拖动系统仿真功能,教学考评功能,与整个轮机模拟器联网的扩展功能。电站监控系统具有配电屏面监视、机舱监控、电力系统实时监视及控制4部分功能,并有运行参数动态监视,报警的记录及打印功能。  相似文献   

20.
VTS作为海事部门实施水上交通安全管理的一种重要手段,在维护良好通航秩序,提高水域通航效率等方面发挥了极其重要的作用。但是,在当前的VTS运行管理工作中,由于法制保障、运行体制、人员素质等方面还存在着许多问题。影响和制约了VTS功能的更好发挥。文章就VTS系统的现状及存在问题进行深入分析,提出了解决这些问题的一些建议和办法,以期在今后的工作中不断改善VTS运行管理环境,使VTS更好地发挥其应有的作用。  相似文献   

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