An efficient computational method for nonlinear three-dimensional wave-wave and wave-body interactions

2006 ◽  
Vol 18 (3) ◽  
pp. 84-88
Author(s):  
Hongmei YAN ◽  
Yuming LIU ◽  
Dick K.P. YUE
Keyword(s):  
Three Dimensional ◽  
Computational Method ◽  
Dimensional Wave

scholarly journals Numerical simulation of the three-dimensional wave-induced currents on unstructured grid

2017 ◽  
Vol 31 (5) ◽  
pp. 539-548
Author(s):  
Ping Wang ◽  
Ning-chuan Zhang ◽  
Shuai Yuan ◽  
Wei-bin Chen
Keyword(s):  
Numerical Simulation ◽  
Unstructured Grid ◽  
Three Dimensional ◽  
Induced Currents ◽  
Wave Induced ◽  
Dimensional Wave

scholarly journals Targets, ripples and spirals in a precipitation system with anomalous dispersion

2015 ◽  
Vol 17 (30) ◽  
pp. 19806-19814 ◽  
Author(s):  
Mahmoud M. Ayass ◽  
Istvan Lagzi ◽  
Mazen Al-Ghoul
Keyword(s):  
Anomalous Diffusion ◽  
Heterogeneous System ◽  
Three Dimensional ◽  
Anomalous Dispersion ◽  
Precipitation System ◽  
Wave Phenomena ◽  
Dimensional Wave

We report multiple three-dimensional wave phenomena in a heterogeneous system due to anomalous diffusion.

scholarly journals Right Ventricular Global and Regional Remodeling in American-Style Football Athletes: A Longitudinal 3D Echocardiographic Study

2021 ◽  
Vol 11 (8) ◽  
pp. 3357
Author(s):  
Amir Hodzic ◽  
Gabriel Bernardino ◽  
Damien Legallois ◽  
Patrick Gendron ◽  
Hélène Langet ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Computational Method ◽  
Physiological Adaptation ◽  
Volumetric Assessment ◽  
American Style ◽  
Few Data ◽  
The Right ◽  
Field Position

Few data exist concerning the right ventricular (RV) physiological adaptation in American-style football (ASF) athletes. We aimed to analyze the RV global and regional responses among ASF-trained athletes. Fifty-nine (20 linemen and 39 non-linemen) ASF athletes were studied before and after inter-seasonal training. During this period, which lasted 7 months, all athletes were exposed to combined dynamic and static exercises. Cardiac longitudinal changes were examined using three-dimensional transthoracic echocardiography. A computational method based on geodesic distances was applied to volumetrically parcellate the RV into apical, outlet, and inlet regions. RV global and regional end-diastolic volumes increased significantly and similarly in linemen and non-linemen after training, with predominant changes in the apex and outlet regions. RV global and regional ejection fractions were preserved. Morphological changes were uniformly distributed among the four cardiac chambers, and it was independent of the field position. Assessment of RV end-diastolic global, inlet and apical volumes showed low intra-observer (3.3%, 4.1%, and 5.3%, respectively) and inter-observer (7%, 12.2%, and 9%, respectively) variability, whereas the outlet regional volumetric assessment was less reproducible. To conclude, ASF inter-seasonal training was associated with a proportionate biventricular enlargement, regardless of the field position. Regional RV analysis allowed us to quantify the amount of exercise-induced remodeling that was larger in the apical and outlet regions.

Effective Shear Area in One Dimensional Ship Hull Finite Element Models to Predict Natural Frequencies of Vibration

2013 ◽  
Author(s):  
Osvaldo Pinheiro de Souza e Silva ◽  
Severino Fonseca da Silva Neto ◽  
Ilson Paranhos Pasqualino ◽  
Antonio Carlos Ramos Troyman
Keyword(s):  
Finite Element ◽  
Natural Frequencies ◽  
Three Dimensional ◽  
Experimental Tests ◽  
Numerical Results ◽  
Computational Method ◽  
Scale Model ◽  
Dimensional Model ◽  
One Dimensional ◽  
Shear Area

This work discusses procedures used to determine effective shear area of ship sections. Five types of ships have been studied. Initially, the vertical natural frequencies of an acrylic scale model 3m in length in a laboratory at university are obtained from experimental tests and from a three dimensional numerical model, and are compared to those calculated from a one dimensional model which the effective shear area was calculated by a practical computational method based on thin-walled section Shear Flow Theory. The second studied ship was a ship employed in midshipmen training. Two models were made to complement some studies and vibration measurements made for those ships in the end of 1980 decade when some vibration problems in them were solved as a result of that effort. Comparisons were made between natural frequencies obtained experimentally, numerically from a three dimensional finite element model and from a one dimensional model in which effective shear area is considered. The third and fourth were, respectively, a tanker ship and an AHTS (Anchor Handling Tug Supply) boat, both with comparison between three and one dimensional models results out of water. Experimental tests had been performed in these two ships and their results were used in other comparison made after the inclusion of another important effect that acts simultaneously: the added mass. Finally, natural frequencies experimental and numerical results of a barge are presented. The natural frequencies numerical results of vertical hull vibration obtained from these approximations of effective shear areas for the five ships are finally discussed.

Two- and three-dimensional locomotion of the nematode Nippostrongylus brasiliensis

Parasitology ◽  
1990 ◽  
Vol 101 (2) ◽  
pp. 301-308 ◽  
Author(s):  
D. L. Lee ◽  
W. D. Biggs
Keyword(s):  
Sodium Alginate ◽  
Intestinal Mucosa ◽  
Three Dimensional ◽  
Viscous Medium ◽  
Nippostrongylus Brasiliensis ◽  
Two Dimensional ◽  
Immune Rejection ◽  
Forward Movement ◽  
Helical Wave ◽  
Dimensional Wave

Locomotion of adult Nippostrongylus brasiliensis has been studied in saline, in 0.6% agar, in sodium alginate of different viscosities and amongst sand grains in these media. In saline the nematode formed two-dimensional waves but there was little forward progression. Amongst sand grains in saline the nematode moved forwards by thrusting against sand grains, but thigmokinetic behaviour later resulted in quiescence. In 0.6% agar and in alginates of weak viscosity the nematode produced two-dimensional waves and sometimes a three-dimensional helical wave which resulted in forward movement. The formation of three-dimensional waves and the distance travelled increased with increasing viscosity up to 4% sodium alginate and also amongst sand gains in these media. In 8% sodium alginate the nematode became coiled like a spring but remained almost stationary. The three-dimensional wave is formed with torsion and obtains thrust from the viscous medium. In the intestine of the host thrust will be obtained from the mucus and villi of the intestinal mucosa. The ability of this nematode to move by two-and three-dimensional undulatory propulsion is probably related to its complex ridged cuticle. Attention is drawn to the role that increased viscosity of mucus may play in entrapping nematodes during their immune rejection.

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