Radial density and temperature profiles at the ion cyclotron wave resonance point.
Plasma electron density as function of radius compared with ion cyclotron heating theory and stability criteria
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Plasma electron density as function of radius compared with ion cyclotron heating theory and stability criteria
Plasma electron density as function of radius compared with ion cyclotron heating theory and stability criteria
Linear stability criteria for panel flutter of thin plates and thin-walled cylinders
Frequency time domain stability criteria for sampled data systems with monotonic nonlinearity
Existence, uniqueness, and stability criteria for linear and nonlinear operational differential equations in Banach and Hilbert spaces
Stability criteria for multiple input, multiple output discrete systems
Second breakdown and other thermal instabilities analyzed by heat flow equation, obtaining stability criteria predicting reduced power dissipation for transistor at low currents
Practical stability of highly eccentric orbits quasi-normal to ecliptic, discussing parameters influence on orbital lifetime with reference to approximate stability criteria
Hydromagnetic self gravitating galactic slab embedded in halo, deriving stability criteria using models of magnetic field
Automatic stabilization and control of computerized nonlinear processes, proposing algorithm for stability criteria
Nonlinear time varying discrete feedback systems input-output properties, deriving stability criteria by generalized small gain and passivity theorems
Distributed parameter systems with transfer function as ratio of output and input multiple transforms, deriving open and closed loop stability criteria
A monograph on problems of stability of equilibrium of mechanical systems with follower forces is presented. Concepts of stability and criteria of stability are reviewed briefly, together with means of analytical specification of follower forces. Nondissipative systems with two degrees of freedom are discussed, and destabilizing effects due to various types of dissipative forces both in discrete and continuous systems, are treated. The analyses are accompanied by some quantative experiments and observations on demonstrational laboratory models.
The stability of spinning flexible satellites in a force-free environment was analyzed. The satellite was modeled as a rigid core having attached to it a flexible appendage idealized as a collection of particles (point masses) interconnected by springs. Both Liapunov and Routh-Hurwitz stability procedures are used. In the former, the Hamiltonian of the system, constrained through the angular momentum integral so as to admit complete damping, is used as a testing function. Equations of motion are written using the hybrid coordinate formulation, which readily accepts a modal coordinate transformation ultimately allowing truncation to a level amenable to literal stability analysis. Closed form stability criteria are generated for the first mode of a restricted appendage model lying in a plane containing the system center of mass and orthogonal to the spin axis. The effects of spin on flexible bodies are discussed by considering a very elementary particle model. Control of passively unstable spacecraft is briefly considered.
Numerical integration methods for the solution of initial value problems for ordinary vector differential equations may be modelled as discrete time feedback systems. The stability criteria discovered in modern control theory are applied to these systems and criteria involving the routine, the step size and the differential equation are derived. Linear multistep, Runge-Kutta, and predictor-corrector methods are all investigated.
This paper presents a Liapunov stability theory applicable to hybrid systems with multi-elastic domains. The mathematical formulation consists of a simultaneous set of ordinary and partial differential equations. A new stability theorem, particularly suited to such hybrid systems, is introduced. To predict the system stability by means of the theorem, it is necessary to construct a functional k, where k is free of spatial derivatives and bounding the Hamiltonian H from below. The conditions under which the construction of such a functional is possible are shown. As an application of the theory, the attitude stability of an earth-pointing satellite with multi-elastic domains is investigated and closed-form stability criteria derived.
The positive limit sets of the solutions of a contingent differential equation are shown to possess an invariance property. In this connection the 'invariance principle' in the theory of Lyapunov stability is extended to systems with unknown, bounded, time-varying parameters, and thus to a large and important class of nonautonomous systems. Asymptotic stability criteria are obtained and applied to guaranteed cost control problems.
Numerical integration methods for the solution of initial value problems for ordinary vector differential equations may be modelled as discrete time feedback systems. The stability criteria discovered in modern control theory are applied to these systems and criteria involving the routine, the step size and the differential equation are derived. Linear multistep, Runge-Kutta, and predictor-corrector methods are all investigated.