On the Statistical Prediction of Sea-margin

本研究项目涉及由于季节效应（风和浪）而导致的海边缘的统计预测，在这种情况下，海边缘是用天气造成的速度损失来表示的。基于准概率论，从螺旋桨竞速和甲板湿润的角度讨论了速度损失的估计方法。采用随机变量持续时间超过某一值的概率过程，重构了螺旋桨运动和甲板湿度统计预测的基本算法。建立了速度损失估计算法。在此基础上，对150米级多螺旋桨集装箱船进行了一系列数值计算。利用卫星信息波资料，研究了船舶响应（螺旋桨运动、甲板湿度等）在海浪中的长期统计趋势。并在九州大学渔业考察船上进行了一系列的海上实验，对算法进行了调查和评价。验证了船舶响应（螺旋桨竞速、甲板湿度、船舶加速度等）的预测。然而，由于速度损失估计算法的复杂性，将速度损失估计算法与螺旋桨运动、甲板湿度等算法结合起来比较困难。为了估计海边缘，有必要进一步研究重建算法。

This research project deals with the statistical prediction of sea-margin because of seasonal effect (wind and waves) in the case the sea-margin is represented by means of speed loss due to weather. The estimating method of speed loss is discussed on the basis of the quasi-probability theory from the viewpoint of propeller racing and deck wetness. The essential algorithm of the statistical prediction for propeller racing and deck wetness are reconstructed by using the probabilistic procedure of time lasting period during which random variable exceeds a value. The algorithms are set up to build the estimating method of speed loss.On the basis of the algorithms, a series of numerical calculations are executed for 150m class container ships with multi-screw propellers. The long-term statistical trend of ship responses (propeller racing, deck wetness etc.) in ocean waves are examined by using satellite information wave data. And a series of experiments are executed with a high-speed boat (Kyushu University fisheries research ship) at sea in order to survey an appraisal of the algorithms.It is certified that the ship responses (propeller racing, deck wetness, ship accelerations etc.) are predicted. However, it is slightly difficult to combine both estimating algorithm of speed loss and the algorithms (propeller racing, deck wetness) for the reason of complexity of those. Further investigations for reconstruction of the algorithms are necessary to estimate sea-margin.