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841.
It is the aim of the European Union to develop a transport policy that supports its economic and sustainable growth and where the concept of sustainable mobility is a driver in the development of such policy. To achieve this goal, the European Union (EU) is promoting the shift of goods to unused existing capacity in rail and sea modes. As such, it is the objective of this paper to carry out a review of the European shipping policy at a time when the EU Member-States are suffering from high levels of congestion, noise and pollution that not only affect the environment but also the quality of life of all citizens. This paper considers the development of EU shipping policy in three stages. 相似文献
842.
Faria Marta V. Baptista Patrícia C. Farias Tiago L. Pereira João M. S. 《Transportation》2020,47(3):1311-1337
Transportation - Considering the role of behavioral and environmental factors on road accidents and traffic intensities, the characterization of vehicle use and driver behavior opens new... 相似文献
843.
为研究隧道进出口路段驾驶员明暗适应的特性及遮阳棚对明暗适应过程的影响规律,文章依托紫荆隧道(无遮阳棚)及巴朗山隧道(有遮阳棚)进行驾驶试验,以驾驶员瞳孔直径及其变化速率为研究参数,分析遮阳棚对隧道进出口路段明暗适应的缓冲效果。研究结果表明:暗适应过程90%以上发生在洞内段,明适应过程54.61%以上发生在洞内段;在隧道进口段暗适应过程中,通过遮阳棚时间为2 s时,最大瞳孔直径变化速率下降4.84%,通过遮阳棚时间为5 s时,最大瞳孔直径变化速率下降33.58%;在隧道出口段明适应过程中,通过遮阳棚时间为2 s时,最大瞳孔直径变化速率下降38.75%,通过遮阳棚的时间为5 s时,最大瞳孔直径变化速率下降49.97%。 相似文献
844.
ROBERT C. HARNEY 《Naval Engineers Journal》2007,119(3):107-121
The United States Government Accountability Office (GAO) has identified problems with the way in which the Department of Defense addresses the growing threat of chemical, biological, radiological, and nuclear (CBRN) weapons. This article describes the conclusions and recommendations of the GAO report. It further analyzes the CBRN threat, the past response of the US Navy to the threat, and how that threat may affect future naval operations. The impact of the potential threat on warship design and performance is discussed. An ad hoc set of design guidelines that can minimize the impact of future threat developments on warship performance is presented. 相似文献
845.
Entropy models are emerging as valuable tools in the study of various social problems of spatial interaction. With the development of the modelling has come diversity. Increased flexibility in the model can be obtained by allowing certain constraints to be relaxed from equality to inequality. To provide a better understanding of these entropy models they are analysed by geometric programming. Dual mathematical programs and algorithms are obtained. 相似文献
846.
Vasilios D. Tsoukalas Dimitrios A. Papachristos Nikolaos K. Tsoumas Elisabeth C. Mattheu 《WMU Journal of Maritime Affairs》2008,7(2):429-448
Qualitative upgrading of the educational process at university level marine education depends largely on the instructive value
of the trainers’ educational software. Marine education software has developed out of a certain initial implementation in
an equivalent manner to which the programs of practice and training have been applied in cases of simulations and programming
environments. In most cases, educational software categories have developed without taking into consideration any special
pedagogical theory. 相似文献
847.
Results of eight tests on stiffened panels under axial compression until collapse and beyond are presented. The tests consider panels with different combinations of mechanical material properties and geometric configurations for the stiffeners including the use of ‘U’-shaped stiffeners. The specimens are three bay panels with associated plate made of high tensile steel S690. Four different configurations are considered for the stiffeners that are made of mild or high tensile steel for bar stiffeners and mild steel for ‘L’ and ‘U’ stiffeners. The influence of the stiffener's geometry on the ultimate strength of the stiffened panels under compression is analyzed. 相似文献
848.
Nathan C. Shahan 《经济导报》2009,(3):49-53
随着美国保德河和圣胡安盆地裸眼煤层甲烷项目的成功开发,20世纪90年代末,澳大利亚的经营者们开始钻探裸,眼垂直并。此后的几年间,澳大利亚早期煤层甲烷经营者凭借着自身的聪明才智、积极创造和灵活变通,使气井设计取得了世界上其它任何煤层甲烷开发项目中前所未有的进展。这些经营者目前正在实施结构复杂的多层多边地表内层(SIS)气井设计,这种设计有望开采全球的煤层甲烷储层。 相似文献
849.
850.
This paper presents an application of shallow water theory to describe the motion of floodwater inside a rolling ship in damage
condition. The time domain theoretical approach to the coupled problems of ship and water inside compartment motions is briefly
described, including the method used to solve for the water motion characteristics and forces exerted on the ship. This approach
is applied to the study of the behaviour of a passenger Ro–Ro ship in regular beam seas and numerical results are given for
the intact and damaged conditions. Comparison is made with experimental results. For the damaged condition, the characteristics
of the floodwater motion are studied in the time domain for a number of different wave frequencies. The shape of the free-surface
and phase of water motion in relation to the ship roll motion are shown for several wave frequencies. The dynamic floodwater
roll moment is also shown and compared with the static roll moment (flat horizontal free surface), allowing the conclusion
that the dynamic roll moment is much larger than the static roll moment, for high wave frequencies, and is in phase opposition
in relation to the roll motion. 相似文献