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301.
This article proposes a decision model for a ship-owner who contemplates the benefits of sailing north via the Northern Sea Route (NSR) or south via the Suez Canal Route (SCR) when transporting oil products from Russia to Asia. The decision is based on potential cost and transit time savings that change on a monthly basis according to sailing conditions and the area along the NSR. This study is applied to a 1A Ice-Class Panamax tanker vessel sailing through the NSR compared to a Panamax tanker vessel sailing through the SCR. It concludes that the NSR provides a competitive advantage in the months from August to November when conservative assumptions on ice conditions (higher bound) are considered for the level of ice thickness encountered along the route and from July to November when a lower bound is assumed. 相似文献
302.
The characteristics and interannual variability of the deep water masses in the North and Central Aegean Sea are being investigated through the data sets of the Hellenic Navy Hydrographic Service (HNHS) and the MEDATLAS 1997 project. In the period between 1987 and 1993, the densest deep water in the Mediterranean has been produced in the Aegean Sea (with σθ densities reaching up to 29.6 kg/m3), contributing to what has been called the Eastern Mediterranean Transient. The examination of time series of mean integrated values of θ, S and σθ below the depth of 500 dbar reveals the significant deep water density increase after 1987 in all of the deep basins in the area. Data suggest that the density increase of 1987–1988 is mainly attributed to a temperature drop, while in 1993, an even more intense density increase is observed, characterized this time by an abrupt salinity increase. We assume that the increased salinity necessary to produce deep water masses with the observed characteristics was not locally produced but rather advected from the Levantine through the South Aegean. After 1993, no new deep water formation episodes have been observed. A series of Θ–S diagrams derived from HNHS CTD casts covering the period between 1993 and 2000, depict the different characteristics of the deep water masses in the area. As 1993 marks the end of the formation period, observed differences between basins in that year must be attributed to different deep water formation sites. Thereafter, the stagnating deep water in the North and Central Aegean basins has been slowly gaining buoyancy by losing salt and gaining heat. The rate at which this phenomenon takes place varies between different deep basins. It is suggested that these variations are linked to the different volumes of each basin as well as to the general circulation features of the Aegean Sea. 相似文献
303.
Continuous measurements of the surface water CO2 partial pressure (pCO2) and the chlorophyll a fluorescence were performed in the Baltic Sea using a fully automated measurement system deployed on a cargo ship. The ship commuted regularly at two day intervals between the Mecklenburg Bight (Luebeck) and the Gulf of Finland (Helsinki). The pCO2 data collected during June 2003 and September 2004 were used to identify biological production events such as the spring bloom and the midsummer cyanobacteria bloom in five different sub-regions. To quantify the net biomass production, the decrease of the total CO2, NCT (normalized to a uniform alkalinity), during the production periods was calculated using the pCO2, temperature and salinity records and the mean alkalinity. Taking into account the CO2 air/sea exchange and the formation of dissolved organic carbon, a simple mass balance yielded the net production of particulate organic carbon which represents the total biomass. The chlorophyll a concentrations obtained from the fluorescence data showed peaks that in most cases coincided with the production maxima and thus supported the interpretation of the pCO2 data. The production during both the spring bloom (2004) and the midsummer nitrogen fixation period (2003) increased by a factor of about three from the southwest to the northeast. For the spring bloom our estimates were significantly higher than those based on the winter nutrient supply and Redfield C / N and C / P ratios. This indicated the existence of additional nutrient sources such as dissolved organic nitrogen, early nitrogen fixation and preferential P mineralization. Midsummer NCT minima were observed only in 2003 and used to quantify the nitrogen fixation activity and to characterize its interannual variability. 相似文献
304.
江海直达驳运输方式研究 总被引：1，自引：0，他引：1
以武钢外矿进江运输为例,对江海直达驳运输方式的可行性进行了研究分析,得到了一些有益的结论。 相似文献
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308.
国内溢油回收船现状及溢油回收装置选型研究 总被引：2，自引：1，他引：1
针对当前海上溢油风险的日益增加,以及防污染对专业溢油回收设备及专业溢油回收船的需求,介绍了目前国内溢油回收船的现状,并对国内外溢油回收装置的特点进行了分析比较,希望为用户在选择溢油回收设备及建设专业溢油回收船方面起到指导作用。 相似文献
309.
李国荣 《广州航海高等专科学校学报》2012,(4):50-52
随着陆地资源不断枯竭,地球上人类的生存和发展将越来越多地依赖于海洋.特别是世界上人口最多、人均土地资源匮乏的中国,由大陆而海洋的资源开发大转移已势在必行,必须要大力重视和开发海洋资源.通过可持续发展理论分别论述了制海权、海洋资源、海洋开发技术的重要性. 相似文献
310.
康熙三十六年（1697）郁永河到台湾采硫,记沿途所见等成《裨海纪游》一书.该书有一节“宇内形势”,记述郁永河对渡台海船的火长等航海人员的访谈,并附有手绘“宇内形势图”一帧.该图实为一航海图,航海人员凭经验绘出明清时期东西洋的大部分航线,与《东西洋航海图》 （the SeldenMap）契合,与古代航海文献亦能相照应.该图对古航海图、航海文献及古航海术的研究多有裨益. 相似文献