In Japan, the accident rate for seamen is 5 times higher than that for all other industries. Many maritime work accidents are related to the poor ergonomic conditions of the working environment. It is particularly important to examine seamen safety in terms of vessel type and seamen age, as these factors are related to various sorts of accidents. In this paper, maritime work accidents were analyzed according to fundamental factors including vessel type, seamen age, and seamen rank. It is suggested that safety education should be provided according specifically to seamen age and vessel type, as they are revealed to be strong factors relating to maritime work accidents. Such education and further research may also lead to improvements in maritime equipment in relation to worker safety.

Recentiy ， port distUrbance and 皿 oo 血 g distUrbance caused by oscillation has been seen as a problem at many 卿 s and bo雌 ， and fishing pomS ， The 舳 。rs clarified the mechanism of port disturbance generation at Kumaishi fishing po鶏 based on field observa 匠on and numerical simulati ． Howeve ろ tl ｝ e limit wave height which cause moor disturbance on small fishing boats has not been clarified ． The autho 埒 have analyzed moo 血 g limit fbcusing on lo 一 period wave heig 瓧s based on past disasters exempla and the numerica1 simUlation resUltS． Conclusions below have been obtained from the analysis ． 〔 1) Moo 血 g distUfbance accompanied by the pass of low − pressu 祀 or 嫉) hoo4 which dainage ship bodies and rdquiie evacuations to other ports ， occur several times a year at Kumaishi Fishirig port ． (2) Fro皿 the hydK) graphic conditions in case ofmooimg distUrbance ， it is clar 面ed 血 at the moo 血 g disturbance occur in case where Hv3 ， which is the hing lo ・ pedod waye heig is over 2． Om and 疏 is()ver O． 10m ， ms also clarified that the 1irnit fc) r long − period wave for sma11 fish 血 g boats is O， 25m s血 ce long 「 period wave inside the port is amp 苴 fied 25 − fc) ld on 廿 1ese cases ． (3) From the frequency of long − periOd wave inrushing to Ku 皿 】 aishi fishing porち it has been clarified that hydrogrqphic condition 蠢 whose HL is over O． 10m is 5． 75％ throu 帥 ayear and it is l4． 71％ in winter ， which is the greatest value il the yea 孰 (4) The quan 飆 ive血dicat () r 『Hlrs (over 2． Qm) " has been銃〔 troduced as a deoision ildicator for evacuations ． 』 吻 mordSt Oceanogアaphicphenomen Long − per わ dwaves ， 」 ｝ d／ ooring limit ，

The present paper proposes two estimation methods for estimating not only the coefficients of roll damping moment but also the coefficients of roll restoring moment without calculation of hydrostatics. The first method is an energy method which involves expanding Froude's method [5] to the case for which the restoring moment is nonlinear. The second method can identify the coefficients of arbitrary form of nonlinear damping and restoring moments by genetic algorithm. The advantage of these methods is that identification of a highly precise coefficient is very easy compared to other conventional methods. This advantage is most important in applications to practical problems. These methods are first applied to numerical simulation data and then to real free-decay data obtained from scale models.

The previous paper which we reported before described a kind of damping function in the equa − tion of single degree of freedom rolling motion which applicable to s 皿 all fishing vesselsc1) ． There is no problem in the application of the damping function to the free rol ！ motion in the ab −

Estimating dynamic roll motion under fishing operation conditions is one of the unresolved problems with respect to the capsize accident of fishing vessels. In addition to potential non-linear response of the roll motion to the wave, unexpected factors occurred by fishing operations make the roll motion complicated. Considering the estimation for the dynamic phenomena generating on the fishing vessels, the numerical simulation based on non-deterministic approaches is one of the effective methods. Among them, it is well-known that a Neural Network model is a practical methodology. Based on the tank tests, the roll response models in fishing operation conditions were constructed. Appropriate estimates for the actual roll motion with a full-scale showed the effectiveness of the Neural Network model. Furthermore, as the model forecasts properly the critical condition occurring for the shipping water, it is suggested that the model is also effective utilizing as the forecasting model to avoid the fishing disaster.