This paper introduces a novel ESPRIT-based closedform source localization algorithm applicable to arbitrarily spaced three-dimensional arrays of vector hydrophones, whose locations need not be known. Each vector hydrophone consists of two or three identical but orthogonally oriented velocity hydrophones plus one pressure hydrophone, all spatially co-located in a point-like geometry. A velocity ...

This work deals with the solution of Navier-Stokes equations governing incompressible flows with variable density, e.g. [10], or dilatable flows for which the Boussinesq approximation is no more valid like low Mach number flows, e.g. [5]. In these cases, the divergence constraint makes the fully-coupled system to solve at each time step for the velocity and dynamic pressure very ill-conditioned...

We prove unconditional long-time stability for a particular velocity-vorticity discretization of the 2D Navier-Stokes equations. The scheme begins with a formulation that uses the Lamb vector to couple the usual velocity-pressure system to the vorticity dynamics equation, and then discretizes with the finite element method in space and implicit-explicit BDF2 in time, with the vorticity equation...

In this paper, we present a fast and accurate method for the combined detection and interactive visualization of vortex structures in 3D flow and their corresponding velocity field. Vortex surfaces are extracted by identifying vortex core lines in combination with isosurfaces of λ2. The velocity field on those vortex surfaces is visualized by a surface LIC method that works in image space. An e...

Context: A visualization of three-dimensional incompressible flows by divergence-free quasitwo-dimensional projections of velocity field on three coordinate planes is proposed. Objective: To visualize 3D incompressible flow by 3 two-dimensional plots. Method: It is argued that such divergence-free projections satisfying all the velocity boundary conditions are unique for a given velocity field....

The calibration of micro inertial measurement units is important in ensuring the precision of navigation systems, which are equipped with microelectromechanical system sensors that suffer from various errors. However, traditional calibration methods cannot meet the demand for fast field calibration. This paper presents a fast field calibration method based on the Powell algorithm. As the key po...

Background. It is well known that overarm throwing is one of the most performed activities in the handball. Shoulder and glenohumeral injuries incidence are high in handball because of both pass, and shooting activity was executed repeatedly in high angular speed. Objectives. This study set out to investigate the usefulness of inexpensive commercial inertial movement sensors for prediction of ...

Recently, we have used the local correlation tracking (LCT) method for mapping horizontal velocity fields in the solar photosphere [Švanda et al, 2005]. The method was applied to processed full-disc dopplergrams acquired by the MDI instrument on board the SoHO observatory. Now, the reliability of this method is verified on synthetic dopplergrams obtained by a very simple numerical simulation of...

This paper presents a methodology to retrieve the full velocity vector of moving targets inducing Doppler-shifts beyond the Nyquist limit determined by the pulse repetition frequency (PRF ). The proposed approach exploits the linear dependence (not subject to PRF limitations) of the Doppler-shift with respect to the slant-range velocity, at each wavelength. By combining the developed scheme to ...