Risk factors  Limits of risk levels   Low  Moderate  High Deformation of the chute [% of chute length]  < 25%  25-50%   > 50% Maximum roll angle of the boarding plat-form and/or life rafts  <20 deg  20-40 deg  >40 deg A further discussion of these results and the significance of the results  on the evacuation situation  is presented below. The  resulting wave climate close to a ship ex-posed to an incident wave with a wave length  of 245 meters (angular velocity 0.5  rad/s) can  be seen in Fig.  7. In this case the incident wave amplitude was ≈ 1.2 m in full scale and the ship was free to drift. The graphs in this figure show the recordings from all meters in Fig.  4 except the incident wave. It can be seen that a propagat-ing  wave appears  on the windward side  and that the absolute amplitudes are approximately the same as the incident wave amplitude. It is also evident that the abso-lute amplitudes are the same on the windward and lee-ward sides. This is due to the fact that for this incident wave system the radiating waves from the ship are small and that no significant reflection  occurs.  The  relative amplitudes on the windward and leeward side are of the same  magnitude and they are as high as the absolute amplitudes. It is also apparent that the relative ampli-tudes are of the same magnitude fore and aft as well as amidships.  In the perspective of the wave system the windward and leeward side would present similar envi-ronments for launching  evacuating equipment for this incident wave situation. When the incident wavelengths are shorter the situation is different. Fig.  8 shows the amplitudes when the inci-dent wave was approximately 60 m (angular velocity 1 rad/s) and the amplitude was 0.6 meters. First it can be noted that a standing wave occurs on the windward side. This implies that the wave amplitudes can be very high at a certain distance from the ship and zero at another distance  from the ship. On  the leeward side the ampli-tudes are significantly lower since a large portion of the incident wave is reflected on the windward side. Due to the ships motions the relative amplitudes are higher than the  absolute wave on  the  leeward side,  but are lower compared to the windward side since the absolute wave amplitudes are higher on this side. On the windward side it is also evident that the relative amplitude amid-ships are higher than  fore and aft which would imply that the situation is less severe fore and aft compared to amidships. For these shorter  waves it is, from the perspective  of the wave climate,  more favorable to Fi Filaunch evacuating equipment on the leeward side. The appearance of the wave  i.e. the smoothness of the waves has also been analyzed in this paper. The situa-tions where the ship was able to drift and the case when the ship  drifted  with an extra drift force to  resemble wind were believed to produce a wake on the windward side and possibly present a better wave appearance  on this side compared to when the ship wasn’t free to drift. The incident  waves were regular.  A valuable tool to examine this situation is Fourier analysis. It was also investigated if an additional frequency could be  ob-served in the  resulting  wave system due to the soft-mooring. The Fourier analyses revealed that the result-ing absolute and relative wave systems only contain one frequency  (corresponding to the incident  wave) thus implying that  the influence of the soft-mooring, drift and additional drift forces didn’t contribute to the waves appearance for the regular  waves used in this paper. This also means that the resulting waves remained within linear potential theory, thus indicating that the wake on the windward side  for the drift scenarios pro-vided no significant influence on the wave appearance. Since the three scenarios produced the same amplitudes and wave appearance for incident waves within linear theory it can  be concluded  that for this  kind  of wave examinations a soft-mooring test setup is sufficient. Results of the Lifeboat Tests The risks the passengers are exposed to when using the lifeboat system  is presented in this  section.  It is com-monly known  that the tested  lifeboat/davit system only fulfils its functions  during gentle weather  conditions. The tests performed in the present study show that  for waves with a wave height of 1m (amplitude 0.5 m) the risk correspond to the risk in still weather. The tests also show  that  in higher waves the risk increases. Fig.  9 shows the influence  of wave and  davit parameters on the  risk of  evacuation  together with an explanation  of symbols. Each circle in the diagram represents the  risk level for one test as described in the section Evaluation of risk. The  risks connected to lifeboat launching  depend on different  factors  for waves with different periods.  The roll motion of  the "mother" ship is small in the shorter waves  (a period of 5  sec, an  angular velocity  of 1.3 rad/s). 旅客船运行时波浪形态的试验研究英文文献和中文翻译(4):http://www.youerw.com/fanyi/lunwen_63433.html