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991.
Olav F. Knudsen 《WMU Journal of Maritime Affairs》2009,8(2):145-172
The short Baltic export route for Russian oil is an attractive source of supply for the European energy market. The article
examines the Russian oil export trade in the Baltic based on Automatic Identification System (AIS) data from 2005 matched
with supplementary data. The first part of the article gives a survey of activities and characteristics of 261 large crude
oil tankers, their flag states and owner countries. The second part views the data in the context of accidental oil spill
risk. Greek and Russian owners are leading carriers in this trade. Russia plays a double leading role as oil exporter and
shipowning country, securing major cargo shares for nationally owned vessels, while also giving a preferential spot in the
trade to Greek owners. Where environmental aspects are concerned, previous research has linked vessel characteristics with
the risk of casualty. Knowledge of flag, age, ownership and activity levels adds useful information about environmental risk.
The data show that flags associated with very high casualty or detention probabilities were represented by 18% of the activity
in this trade. Older vessels have a similar share, and at this particular time probably represent the more serious threat
of accidental oil spills. 相似文献
992.
Plates form one of the basic elements of structures. Land-based structures may be subjected to air blast loads during combat environment or terrorist attack, while marine structures may be subjected to either air blast by the attack of a missile above the water surface or an underwater explosion by the attack of a torpedo or a mine or a depth charge and an aircraft structure may be subjected to an in-flight attack by on-board explosive devices. Furthermore, gas explosion occurs in offshore installations and industries. This review focuses on the phenomenological evolution of blast damage of plates. 相似文献
993.
AbstractIndoor simulator and on-road instrumented vehicle are the most popular ways to analyze driving behaviors by using collected Vehicle Sensor Data (VSD). However, for a same driver, the driving performance could be different in the real world and in the simulated world. Even though many studies have been conducted to discover the differences of driving behaviors in these two circumstances, little research has focused on analyzing the differences in driving style, which can provide more integrated knowledge of a driver from the natural structure, stimulus–response mechanism, of driving behaviors. Therefore, in this paper, the driving styles in both the real world and the simulated world are extracted by implementing the nonnegative matrix factorization method on the collected VSD data. Through this analysis, the driving style differences can be quantitatively described and discussed in detail. It is found that the drivers tend to be more unstable and sometimes aggressive when driving the simulator and the deviation in the perception of temporal gap in two circumstances is also discovered. The research findings are particularly valuable to calibrate the driving simulator and construct more reliable driving behavior models. 相似文献
994.
文章以南通市普通高校为研究对象,采用问卷调查法、文献资料查阅、数理统计等方法,对六所高校的公共体育教学改革状况进行研究.研究结果表明:目前南通市普通高校公共体育课程教学指导思想的改革效果明显,但体育教学模式和体育教学内容的改革仍需继续加强。 相似文献
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Charles L. Siemon 《Coastal management》2013,41(1):93-96
Abstract The Florida Keys are an example of a fragile resource threatened by development. The early division of the area into small lots made conventional planning and regulation difficult. This paper describes the creation of a conservancy for the Keys—the history of development, the conditions necessitating a conservancy, and the political wrangling it took to implement the conservancy. 相似文献
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