transverse bulkheads (at each station from 0#~20#) were used to reinforce the transverse stiffness of the model
measures the weighted average of
where ballast blocks were located。 The weight and lo-
cations of the ballast blocks were suitably arranged to satisfy the similitude of the longitudinal weight distri- bution and the position of the centre of gravity of the
the functionnear the ‘jth ’ point of the data set on
ship。 Chen et al (2001) describes in detail the principal
frequency level (n-1), and c j
measures the weighted
particulars of the S175 container ship and the flexible
change in the function near the ‘jth’ point。
Repetition of this procedure for the term including
nm
model manufacturing process。
The model was self-propelled, travelling with the car- riage, and allowed to freely surge, heave, pitch and
a j , m 1,。。, n
and accounting for the periodic be-
vibrate vertically。 Sway, roll and yaw motions were
haviour of the extended series of samples, the signal expression takes the form
restricted。 The speed of the model was set for a pre- scribed propeller revolution rate of the ship and was
measured by the speed of the towing carriage。
Stresses, vertical bending moments, vertical accelera- tions at the FP, and heave and pitch motions were
measured。 The 2-node frequency of the ship model floating in still water and, the vertical steady state
bending moment due to the forward speed were also
measured。 The heave and pitch motions were measured
ponent motion measuring device。 A servo needle type wave height meter was firmly attached to the towing carriage with the probe positioned approxi-
mately 4。5m in front of the model’s centre of gravity。文献综述
Vertical accelerations were measured by an acceler- ometer installed on the deck at the centreplane of Sta-
tion 20。 The bending moments were measured through
Eq。 7 represents a linear operation and provides the wavelet expression describing a series of data by a se- ries of functions originally arising from a base of scal- ing functions and wavelet functions by shifting and compressing the independent variable x。 At each fre- quency level n-m (m=1, 2, …, n+1), the basis functions
strain gauges fixed on the starboard side-deck plate at
longitudinal stations。 The relation between the vertical bending moment and the value of strain was derived by a static calibration method assuming that the creepage of the material is small and can be neglected。 The loca- tions of these measurement points were:
M1 near Station 15 (2。65m from AP); M2 at Station 12。5;
M3 near Station 10 (1。85m from AP); M4 at Station 7。5;
M5 near Station 5 (0。95m from AP)。
The experimental conditions for the S175 container ship model travelling at Fn=0。275 in regular head waves are listed in Table 1(: wavelength, a: wave amplitude)。
Table 1: Experimental test conditions
Head sea, Fn=0。275
Case 2a/ Lpp 极端波浪载荷实验船模的小波分析英文文献和中文翻译(4):http://www.youerw.com/fanyi/lunwen_94996.html