{"product_id":"9789401065702","title":"Frequency Methods in Oscillation Theory (Mathematics and Its Applications (Closed)) (Reprint)","description":"\u003cp\u003eThe linear theory of oscillations traditionally operates with frequency representa- tions based on the concepts of a transfer function and a frequency response. The universality of the critria of Nyquist and Mikhailov and the simplicity and obvi- ousness of the application of frequency and amplitude - frequency characteristics in analysing forced linear oscillations greatly encouraged the development of practi- cally important nonlinear theories based on various forms of the harmonic balance hypothesis [303]. Therefore mathematically rigorous frequency methods of investi- gating nonlinear systems, which appeared in the 60s, also began to influence many areas of nonlinear theory of oscillations. First in this sphere of influence was a wide range of problems connected with multidimensional analogues of the famous van der Pol equation describing auto- oscillations of generators of various radiotechnical devices. Such analogues have as a rule a unique unstable stationary point in the phase space and are Levinson dis- sipative. One of the pioneering works in this field, which started the investigation of a three-dimensional analogue of the van der Pol equation, was K. O.\n\u003cbr\u003eFriedrichs's paper [123]. The author suggested a scheme for constructing a positively invariant set homeomorphic to a torus, by means of which the existence of non-trivial periodic solutions was established. That scheme was then developed and improved for dif- ferent classes of multidimensional dynamical systems [131, 132, 297, 317, 334, 357, 358]. The method of Poincare mapping [12, 13, 17] in piecewise linear systems was another intensively developed direction.\u003c\/p\u003e","brand":"Springer Verlag","offers":[{"title":"Default Title","offer_id":52364941689143,"sku":"00000_00000_00000_00000","price":595.92,"currency_code":"MYR","in_stock":true}],"url":"https:\/\/kinokuniya.com.my\/products\/9789401065702","provider":"Books Kinokuniya Malaysia","version":"1.0","type":"link"}