We present a derivation of exponential shape functions for the convection diffusion problem. The shape functions are defined for triangular elements and can be regarded as an extension of the one-dimensional Scharfetter-Gummel discretization scheme to two dimensions. The shape function varies exponentially in the direction of the element field vector and linearly in the direction orthogonal to ...

Introduction Left ventricular (LV) twist is believed to store potential energy and plays an important role in generating diastolic suction. Recent advances in echocardiography techniques have allowed quantification of LV twist. The aim of the present study was to compare LV twist and torsion in healthy human subjects determined by velocity vector imaging (VVI) and tissue Doppler imaging (TDI) a...

INTRODUCTION Two-dimensional strain analysis is a powerful analysis modality, however, clinical utilization has been limited by variability between different analysis systems and operators. We compared strain in adults and children using vendor-specific and vendor-independent software to evaluate variability. METHODS One hundred and ten subjects (50/110 pediatric, 80/110 normal left ventricul...

This paper is devoted to trajectory tracking control for port-Hamiltonian systems. The control law presented here is extension of an existing passive velocity field controller for fully actuated mechanical systems. The proposed method employs vector fields on the phase (co-tangent) spaces instead of those on the velocity (tangent) spaces. Since port-Hamiltonian systems can describe a wider clas...

Doppler velocity measurements from airborne meteorological Doppler radars require removal of the aircraft motion contribution in order to provide radial velocity of hydrometeor targets. This is a critical step for hydrometeor motion and wind retrievals. The aircraft motion contribution is defined as the scalar product between the radar antenna beam-pointing vector and the aircraft velocity vect...

introduction left ventricular (lv) twist is believed to store potential energy and plays an important role in generating diastolic suction. recent advances in echocardiography techniques have allowed quantification of lv twist. the aim of the present study was to compare lv twist and torsion in healthy human subjects determined by velocity vector imaging (vvi) and tissue doppler imaging (tdi) a...

The evolution of the charge density distribution function is simulated for both the case of a uniformly charged sphere with zero initial conditions and for the case of a non-uniform charged sphere. For the case of a uniformly charged sphere, the comparison of a numerical result and an exact analytical solution, demonstrated the agreement between the results. The process of “scattering” of a cha...

Skid‐steered mobile robots have been widely used in exploring unknown environments and in military applications. In this paper, the tuning fuzzy Vector Field Orientation (FVFO) feedback control method is proposed for a four track wheel skid‐steered mobile robot (4‐TW SSMR) using flexible fuzzy logic control (FLC). The extended Kalman filter is utilized to e...

The transverse velocities of steadily rotating, non–axisymmetric patterns in flat galaxies may be determined by a purely kinematical method, using two dimensional maps of a tracer surface brightness and radial current density. The data–maps could be viewed as the zeroth and first velocity moments of the line–of–sight velocity distribution, which is the natural output of integral– field spectrog...

Classical hydrophones measure pressure only, but acoustic vector-sensors also measure particle velocity. Velocity measurements can increase array gain and resolve ambiguities, but make vector-sensor arrays more difficult to analyze. This thesis derives a new set of useful performance measures for acoustic vector-sensor arrays. It characterizes the vector-sensor array beampattern with and withou...