In this study, we tackle with one single effort, three fundamental problems in ship hydrodynamics, namely the attraction force exerted on a single ship moving rectilinearly close and parallel to a rigid wall（berthing...In this study, we tackle with one single effort, three fundamental problems in ship hydrodynamics, namely the attraction force exerted on a single ship moving rectilinearly close and parallel to a rigid wall（berthing）, the determination of the associated added-mass coefficients（maneuvering） and finally evaluating the forces exerted on a ship in a two-ship crossing scenarios. The novelty of the present approach relies on using Weinblum’s proposition to assimilate the ship’s hull by an ＂equivalent＂ tri-axial ellipsoid, as well as the employment of ellipsoidal harmonics expansion techniques.展开更多
In magnetoencephalography （MEG） a primary current is activated within a bounded conductive medium, i.e., the head. The primary current excites an induction current and the total （primary plus induction） current ge...In magnetoencephalography （MEG） a primary current is activated within a bounded conductive medium, i.e., the head. The primary current excites an induction current and the total （primary plus induction） current generates a magnetic field which, outside the conductor, is irrotational and solenoidal. Consequently, the exterior magnetic field can be expressed as the gradient of a harmonic function, known as the magnetic potential. We show that for the case of a triaxial ellipsoidal conductor this potential is obtained by using integration along a specific path which is dictated by the geometrical characteristics of the ellipsoidal system as well as by utilizing special properties of ellipsoidal harmonics. The vector potential representation of the magnetic field is also obtained.展开更多
文摘In this study, we tackle with one single effort, three fundamental problems in ship hydrodynamics, namely the attraction force exerted on a single ship moving rectilinearly close and parallel to a rigid wall（berthing）, the determination of the associated added-mass coefficients（maneuvering） and finally evaluating the forces exerted on a ship in a two-ship crossing scenarios. The novelty of the present approach relies on using Weinblum’s proposition to assimilate the ship’s hull by an ＂equivalent＂ tri-axial ellipsoid, as well as the employment of ellipsoidal harmonics expansion techniques.
文摘In magnetoencephalography （MEG） a primary current is activated within a bounded conductive medium, i.e., the head. The primary current excites an induction current and the total （primary plus induction） current generates a magnetic field which, outside the conductor, is irrotational and solenoidal. Consequently, the exterior magnetic field can be expressed as the gradient of a harmonic function, known as the magnetic potential. We show that for the case of a triaxial ellipsoidal conductor this potential is obtained by using integration along a specific path which is dictated by the geometrical characteristics of the ellipsoidal system as well as by utilizing special properties of ellipsoidal harmonics. The vector potential representation of the magnetic field is also obtained.
