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11.
Coastal shipping is one of the most sustainable and economically competitive modes of transportation. This study employs the analytic hierarchy process (AHP) method to determine the importance of various factors influencing container carriers’ use of coastal shipping. A three-level hierarchical structure with the 17 attributes is proposed and tested. A previous AHP survey in Taiwan has indicated that port policy and infrastructure is the most critical factor influencing the coastal shipping by container carriers followed by operational cost, operational strategy and operational efficiency. Overall, the results indicate that the five most important attributes influencing the use of coastal shipping are simplified customs procedures; leasing a dedicated terminal; transhipment time; a favourable port charge system and efficient terminal operations. 相似文献
12.
Forng-Chen Chiu Wen-Chuan Tiao Jenhwa Guo 《Journal of Marine Science and Technology》2009,14(2):228-239
The present study focuses on the nonlinear behavior of pressure on the hull surface of a high-speed vessel in irregular waves,
particularly the pressure responses of alternately wet and dry areas near the waterline and on the bow zone. The vessel has
high deadrise angles that may be subject to slight impact and water pile-up effects. A series of experiments in regular and
irregular head waves were conducted, and the validity of applying Volterra modeling was investigated. In a previous article
using experimental data in regular waves, it was confirmed that the approximate third-order Volterra model adequately simulated
the variation of pressure responses in regular waves of different steepness up to a wave amplitude with a wavelength ratio
of 0.01, even for the highly nonlinear pressures acting on the abovementioned areas of the hull surface. In this article,
further validation for the second part of the study was obtained using experimental data in irregular waves. The frequency
response functions obtained from the previous study’s experimental data in regular waves were applied to the third-order Volterra
model by combining the input of irregular waves to simulate the responses in irregular waves of sea state five. Then, the
spectra and statistics were analyzed. For the motions, accelerations, and pressure responses in irregular waves (as well as
for the simulated time histories) variance spectra and statistics such as cumulative distributions of peak values and probability
density functions were compared with the experimental results. It was confirmed that even for highly nonlinear and non-Gaussian
pressures on the abovementioned areas of the hull surface, the approximate third-order Volterra model simulates the pressure
responses in irregular head waves up to a sea state of five with adequate accuracy on deterministic and statistical bases. 相似文献