Stability of SAS-A dual spin spacecraft with energy dissipation on the momentum wheel
Stability of SAS-A dual spin spacecraft with energy dissipation on momentum wheel
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Stability of SAS-A dual spin spacecraft with energy dissipation on momentum wheel
Numerical analysis of internal supersonic flows with diffusion, dissipation, and hydrogen-air combustion
E layer kinetic energy viscous dissipation and transfer to potential energy by turbulence and irregular winds shear
Electrostatic drift-dissipative plasma instability and nocturnal equatorial spread F irregularities, discussing amplification in collision dominated medium
Solar wind magnetic field power spectra and plasma velocity, discussing turbulence, viscosity and dissipation
Hydromagnetic shock waves structure, investigating resistive, viscous and thermal conduction dissipation effects on discontinuities
Collisionless plasma, calculating effects of energy dissipation due to weak firehose instability on steady planar flow, based on quasi- linear fluid equations
Facilities for testing linear antenna electrical properties in infinite, homogeneous, isotropic, dissipative medium
General theory of dissipative periodic processes for systems defined by partial, functional, or neutral differential equations
Amplitude dispersion and stability of dissipative weakly nonlinear waves determined by perturbation method
Spin-axis attitude stability of dissipative dual spin spacecrafts in force-free environment
Trailing vortices behind wing tip with vortex dissipator, using wind tunnel flow visualization and flight tests
The abstract theory presented shows how the theory of dissipative systems of ordinary differential equations can be extended to include a wide class of functional and partial differential equations. Since the basic hypotheses are all in terms of boundedness, finding sufficient conditions in terms of Liapunov functions was not difficult. Work is being undertaken to solve some nontrivial examples to illustrate how the theory can applied.
The relation between dissipation and temperature structure in the lower corona was empirically determined. This relation was then used in conjunction with the observed structure to estimate the damping length for mechanical waves.
The heating and movement of the upper atmosphere at ionospheric levels in response to electric currents are discussed. Joule dissipation, generation of winds, and pressure gradients are significant factors in the energetics of the ionospheric electric currents flowing during magnetic storms and also of the Sq current system.
Modifications to the existing inviscid theory of long-wave propagation in rotating fluids are studied. A modification to the Korteweg-deVries equation is found to describe weak dissipation in long waves in a swirling fluid. General features of solutions are discussed, and a solution for the damping of solitary waves is presented.
Investigation of the effects of blood viscosity on dissipation as well as dispersion of small waves in arteries and veins by means of a parametric study. A linearized analysis of axisymmetric waves in a cylindrical membrane that contains a viscous fluid indicates that there are two families of waves: a family of slow waves and one of fast waves. The faster waves are shown to be more sensitive to variations in the elastic properties of the medium surrounding the blood vessels and at high values of the frequency parameter alpha. At low values of alpha the effects of viscosity on attenuation are reversed.
A theory is presented that shows how the concept of dissipative systems of ordinary differential equations can be extended to include a broad class of functional and partial differential equations, such as retarded functional differential equations and parabolic partial differential equations. Since the basic hypotheses are all in terms of boundedness, finding sufficient conditions in terms of Liapunov functions would not be too difficult.