scholarly journals Effect on Ship Maneuvering Motion under Strong Tidal Current

2002 ◽  
Vol 106 (0) ◽  
pp. 113-120
Author(s):  
Yasuyuki NIWA ◽  
Masayoshi NUMANO ◽  
Junji FUKUTO ◽  
Mitsuo TADA
2005 ◽  
Vol 49 (02) ◽  
pp. 69-79 ◽  
Author(s):  
Ming-Chung Fang ◽  
Jhih-Hong Luo ◽  
Ming-Ling Lee

In the paper, a simplified six degrees of freedom mathematical model encompassing calm water maneuvering and traditional seakeeping theories is developed to simulate the ship turning circle test in regular waves. A coordinate system called the horizontal body axes system is used to present equations of maneuvering motion in waves. All corresponding hydrodynamic forces and coefficients for seakeeping are time varying and calculated by strip theory. For simplification, the added mass and damping coefficients are calculated using the constant draft but vary with encounter frequency. The nonlinear mathematical model developed here is successful in simulating the turning circle of a containership in sea trial conditions and can be extended to make the further simulation for the ship maneuvering under control in waves. Manuscript received at SNAME headquarters February 19, 2003; revised manuscript received January 27, 2004.


2020 ◽  
Vol 216 ◽  
pp. 107994
Author(s):  
Zihao Wang ◽  
Haitong Xu ◽  
Li Xia ◽  
Zaojian Zou ◽  
C. Guedes Soares

2015 ◽  
Vol 52 ◽  
pp. 212-221 ◽  
Author(s):  
Cao Jian ◽  
Zhuang Jiayuan ◽  
Xu Feng ◽  
Yin Jianchuan ◽  
Zou Zaojian ◽  
...  

1991 ◽  
pp. 71-80
Author(s):  
Mitsushige SAKAMOTO ◽  
Masatoshi SASAKI ◽  
Masaaki KITAGUCHI ◽  
Kanji IMAI

2016 ◽  
Vol 95 (4) ◽  
pp. 419-428
Author(s):  
K. Gersie ◽  
P.G.E.F. Augustinus ◽  
R.T. Van Balen

AbstractHumans have played an important role in fluvial systems because of the impact of their land-use activities, frequently leading to degradation of environmental conditions. Rivers, which are the primary agents in sediment transport, have thus been subject to changes in sediment fluxes. The Suriname River has been affected by anthropogenic activities since colonial times, and has experienced strong discharge and sediment-load changes since the construction of the Afobaka Dam in 1964. The river's estuary sediments largely consist of fine-grained sediments, originating, ultimately, from the Amazon River and transported by the strong tidal current. The influence of this tidal current is diminished at the head of the estuary, allowing the river flow to become dominant. Also remarkable is the interaction of the Suriname River and the westward-migrating mudbanks which is evident in the changing magnitude and volume of Braamspunt, a mudcape located at the mouth of the estuary. The regulated discharge of the river results in a change of the river's morphology, resulting, among other things, in the growth of river bars.


Author(s):  
Yin Jian-Chuan ◽  
Zou Zao-Jian ◽  
Xu Feng

Partial least squares (PLS) regression is used for identifying the hydrodynamic derivatives in the Abkowitz model for ship maneuvering motion. To identify the dynamic characteristics in ship maneuvering motion, the derivatives of hydrodynamic model's outputs are set as the target output of the PLS identification model. To verify the effectiveness of PLS parametric identification method in processing data with high dimensionality and heavy multicollinearity, the identified results of the hydrodynamic derivatives from the simulated 20 deg/20 deg zigzag test are compared with the planar motion mechanism (PMM) test results. The performance of PLS regression is also compared with that of the conventional least squares (LS) regression using the same dataset. Simulation results show the satisfactory identification and generalization performances of PLS regression and its superiority in comparison with the LS method, which demonstrates its capability in processing measurement data with high dimensionality and heavy multicollinearity, especially in processing data with small sample size.


Author(s):  
Weilin Luo ◽  
C. Guedes Soares ◽  
Zaojian Zou

Combined with the free-running model tests of KVLCC ship, the system identification (SI) based on support vector machines (SVM) is proposed for the prediction of ship maneuvering motion. The hydrodynamic derivatives in an Abkowitz model are determined by the Lagrangian factors and the support vectors in the SVM regression model. To obtain the optimized structural factors in SVM, particle swarm optimization (PSO) is incorporated into SVM. To diminish the drift of hydrodynamic derivatives after regression, a difference method is adopted to reconstruct the training samples before identification. The validity of the difference method is verified by correlation analysis. Based on the Abkowitz mathematical model, the simulation of ship maneuvering motion is conducted. Comparison between the predicted results and the test results demonstrates the validity of the proposed methods in this paper.


1981 ◽  
Vol 28 (325) ◽  
pp. 207-222 ◽  
Author(s):  
S. Inoue ◽  
M. Hirano ◽  
K. Kijima ◽  
J. Takashina

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