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51.
在九月召开的国际航空货运协会世界航空货运论坛上&;#183;波音公司发布了其两年一度的世界航空货运预测报告,其中鲜有特别的内容。 相似文献
52.
From a comparative study it is concluded that current design rules for the spherical pressure hull of manned submersible need to be updated and unified. In this paper, a series of spherical pressure hulls are calculated by nonlinear FEM. Based on these numerical results, the influence of critical arch length and the relationship of ultimate strength with t/R and structural imperfection are studied. Finally, empirical formulae for the ultimate strength of the titanium alloy spherical pressure hull of deep manned submersible based on numerical computations are given. The formulae can be used as the core equations to update current design rules. 相似文献
53.
Martin Stopford 《上海造船》2010,(1):12-16
阐述了两年来的中国和世界海运经济发展,介绍了中国航运和造船业现状和两年来的发展,回顾了这两年世界经济发展进程中发生的一系列事件及其对航运业和海运贸易的影响,指出最严峻的挑战是如何应对此次造船订单和产能危机,总结了可能面对的挑战与机遇 相似文献
54.
Since the economic reforms in the late 1970s, the shipbuilding industry in China has enjoyed rapid growth. Over the past two decades, many new building contracts have been won and successfully completed. However, some shipyards have also suffered great losses. Basing on their experience in Southern China, the authors examine some of the major challenges that Chinese shipbuilders faced during this transitional period, when the industry ventured into the international market. These challenges are broadly categorized into two areas: (i) external factors, such as inflation and infrastructural support that the shipbuilder had no control over, and (ii) shipbuilding management, which the shipbuilder had to master in order to gain competitive advantage. Suggestions on how these problems could be tackled are discussed. 相似文献
55.
Håkan T. Sandersen 《Coastal management》2013,41(5):447-463
This article discusses the impact of the Norwegian government's administrative reform on the management of the Norwegian aquaculture industry and coastal areas. The 2010 reform of government administration strengthened the County Councils’ role in issues of aquaculture at the expense of the regional offices of the Directorate of Fisheries. The aim of the reform was to increase self-governance through decentralization. However, international trends in coastal zone and marine resource management are moving in the opposite direction, aiming at more integrated and ecosystem-based approaches involving the management of larger, rather than smaller, geographic regions. This article examines the possible effects of this reform in light of the move from government to governance, and in the context of a broad policy shift toward a more integrated, ecosystem-based management (EBM) of the coastal zone. Based on insights from multi-level and coastal zone governance debates, we argue that an unintended consequence of the Norwegian administrative reform could be increased fragmentation of the aquaculture governance system, as well as a reduced capacity to implement EBM-related measures. At the same time, the reform might improve coastal zone planning, although a further step toward integrated coastal zone management (ICZM) would require a greater delegation of authority to the County Councils. 相似文献
56.
H. Yasukawa T. Hirono Y. Nakayama K. K. Koh 《Journal of Marine Science and Technology》2012,17(3):291-304
In order to achieve safe navigation, it is important to be able to understand and calculate the effects of an external force on the maneuvering behavior of a ship. This paper analyzes the course stability and yaw motion of a ship traveling under steady wind conditions. A course stability criterion and approximate formulae for the yaw motion in steady wind, including the aero/hydrodynamic force derivatives for the ship, are derived. To confirm the reliability of the criterion and formulae, they were used to investigate a pure car carrier in steady wind. The results of this investigation revealed that course instability appears in the head and following wind directions, mainly under the influence of aerodynamic derivatives with respect to the yaw restoring forces. However, this course instability can be reduced by applying steering control. For winds ranging from head winds to beam winds, yaw oscillation appears when the period is relatively long and the damping is small. The analytical formulae derived here can be used to gain a better understanding of ship maneuvering behavior in steady wind. 相似文献
57.
Synergies between Adjacent Beach-Nourishing Communities in a Morpho-Economic Coupled Coastline Model
Beach “nourishment” consists of placing sand on an eroding beach. The widened beach provides increased storm protection to adjacent structures and improved recreational benefits, but is most often transient, requiring on-going, repeated nourishment episodes. Numerical models of beach nourishment typically address such questions as how long a widened beach will last; economic models compare the benefits and costs of preserving a stretch of beach without regard to its geomorphic evolution. Neither have addressed the physical nor economic interactions between adjacent nourishing communities. Here, we couple a numerical model of coastline evolution and a cost-benefit model of beach nourishment, allowing adjacent communities to make dynamic nourishment decisions. Beach nourishment benefits adjacent communities both “updrift” and “downdrift.” The total amount of money spent on nourishment activities can decrease by as much as 25% when adjacent communities both conduct on-going nourishment projects, as opposed to the case where each community nourishes in isolation. 相似文献
58.
Jee In Yoon Gerard T. Kyle Carena J. van Riper Stephen G. Sutton 《Coastal management》2013,41(6):457-469
This study explores the relationship between Australian's attitudes toward climate change impacts on the Great Barrier Reef (GBR) and environmentally responsible behavior (ERB). We hypothesize that general attitudes toward climate change, subjective norms, and perceived behavioral control predict intended and reported behavior, and that attitude negatively influences constraints on adopting ERB. The moderating effect of residential condition (urban vs. rural contexts) was tested across these hypothesized relationships. We randomly selected 200 individuals from eight regions: Five within 50 km of the GBR Coastline and three from the Statistical Metropolitan Areas in Australia. We yielded 1,623 surveys by telephone interviews. Findings confirm our hypotheses and suggest the most important predictor of intentions is perceived behavioral control. The two groups of respondents (urban vs. rural) illustrate different relationships. This study offers insight on how managers of the GBR can effectively shape residents' behavioral tendencies that minimize human impacts on the natural environment. 相似文献
59.
60.
The galvanic corrosion behavior of the metal combinations 15 CDV6/MDN138 and 15 CDV6/MDN250, with 1:1 area ratio, has been studied in natural seawater using the open well facility of CECRI's Offshore Platform at Tuticorin for a year. The open circuit potentials of MDN138, MDN250, and 15 CDV6 of the individual metal, the galvanic potential and galvanic current of the couples 15 CDV6/MDN138 and 15 CDV6/MDN250, were periodically monitored throughout the study period. The calcareous deposits on MDN138 and MDN250 in galvanic contact with 15 CDV6 were analyzed using XRD. The electrochemical behavior of MDN138, MDN250, and 15 CDV6 in seawater was studied using an electrochemical work station. The surface characteristics of MDN138 and MDN250 in galvanic contact with 15 CDV6 have been examined with a scanning electron microscope. The results of the study reveal that the galvanic protection offered by15 CDV6 to MDN250 and MDN138 in natural seawater amounts to 93% and 98%, respectively, implying that the galvanic protection offered by 15 CDV6 is continuous and effective, which has been further evinced from the adherent nature of the calcareous deposit film comprising compounds such as CaCO_3(calcite, aragonite, and vaterite), MgCO_3(magnesite),Mg(OH)_2(brucite), and MgO(brucite). 相似文献