Results 261 to 270 of about 5,559,654 (298)

An Example in the Theory of Nonlinear Oscillations

SIAM Journal on Applied Mathematics, 1969
We shall show that condition (4), in conjunction with all the conditions of the theorem except (2), is not sufficient. Whether it is necessary is apparently still open. However, results in [4] show that Wong's conjecture is true in the case where f(x) is also nondecreasing (or bracketed between two nondecreasing functions that satisfy (4)). An analysis
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The Matrix Theory of Torsional Oscillations

Journal of Applied Physics, 1942
The general case of vibration of a shaft with several rotating masses is discussed. The analysis is reduced to a simple matrix multiplication of second-order matrices and the natural frequencies of symmetrical systems are discussed. The connection of the matrix method and the well-known Holzer method of computing the natural frequencies of torsional ...
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The theory of prey-predator oscillations

Theoretical Population Biology, 1976
Abstract A general prey-predator model is formulated and the conditions for the occurrence of limit cycles are discussed. The effects of random environmental fluctuations on a stable equilibrium and on a limit cycle are investigated. Data on the 4- and 10-yr cycles are analysed by computing the periodogram and the results are compared with the ...
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Theory of a quantum anharmonic oscillator

Physical Review A, 1988
The time evolution of a quantum single-quartic anharmonic oscillator is considered. The study is carried on in operational form by use of the raising and lowering operators of the oscillator. The equation of motion is solved by application of a new integration method based on iteration techniques, and the rigorous solutions that describe the time ...
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Comparison of theories of Teorell's membrane oscillator

Protoplasma, 1967
Teorell’s membrane oscillator (Teorell 1959) consists of a silica gel wide pore membrane which separates two compartments containing the same electrolyte but with different concentrations. When a critical value of constant current flows through the membrane, oscillations of potential difference and pressure difference across the membrane are observed ...
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Location of low-frequency oscillation sources using improved D-S evidence theory

International Journal of Electrical Power and Energy Systems, 2021
Chenghong Gu, Da Xie
exaly  

Relative oscillation theory for linear Hamiltonian systems with nonlinear dependence on the spectral parameter

Mathematische Nachrichten, 2023
Julia Elyseeva
exaly  

Positivity of solutions of adapted generalized Riccati equation with consequences in oscillation theory

Applied Mathematics Letters, 2021
Michal Vesely, Petr Hasil
exaly  

Relative oscillation theory for Sturm–Liouville operators extended

Journal of Functional Analysis, 2008
Gerald Teschl, Helge Kruger
exaly  

On the complex oscillation theory of f ″ + A (z)f = 0 where A (z) is analytic in the unit disc

Mathematische Nachrichten, 2009
Tingbin Cao
exaly