this paper studies the generalized version of thezakharov-kuznetsov benjamin-bona-mahoney equation. the functionalvariable method as well as the simplest equation method areapplied to obtain solitons and singular periodic solutions to theequation. there are several constraint conditions that arenaturally revealed in order for these specialized type ofsolutions to exist. the results of this pape...

this paper proves the existence and uniqueness of quadratic mean almost periodic mild so-lutions for a class of stochastic dierential equations in a real separable hilbert space. themain technique is based upon an appropriate composition theorem combined with the banachcontraction mapping principle and an analytic semigroup of linear operators.

This paper proves the existence and uniqueness of quadratic mean almost periodic mild so-lutions for a class of stochastic dierential equations in a real separable Hilbert space. Themain technique is based upon an appropriate composition theorem combined with the Banachcontraction mapping principle and an analytic semigroup of linear operators.  

the study of the dynamic behavior of a rigid body with one fixed point (gyroscope) has a long history. a number of famous mathematicians and mechanical engineers have devoted enormous time and effort to clarify the role of dynamic effects on its movement (behavior) – stable, periodic, quasi-periodic or chaotic. the main objectives of this review are: 1) to outline the characteristic features of...

This is a joint project begun in 1983 and first reported in (Abraham, 1989). We were inspired by Arthur Winfree and have in mind a number of applications to medical physiology and mathematical biology. The main theme is the role of the geometry of periodic attractors -the shape of an attractive limit cycle and its isochrons -in determining the phase synchrony of a network of heterogeneous oscil...

agriculture as one of the major economic sectors of iran, has an important role in gross domestic production by providing about 14% of gdp. this study attempts to forecast the value of the agriculture gdp using periodic autoregressive model (par), as the new seasonal time series techniques. to address this aim, the quarterly data were collected from march 1988 to july 1989. the collected data w...

Using the Gauss linking integral we define a new measure of entanglement for a collection of closed or open chains, the linking matrix. For a system employing periodic boundary conditions (PBC) we use the periodic linking number and the periodic selflinking number to define the periodic linking matrix. We discuss its properties with respect to the cell size used for the simulation of a periodic...

Periodic electroencephalographic (EEG) patterns consist of discharges usually epileptiform in appearance, which occur at regular intervals, in critical patients. They are commonly classified as periodic lateralized epileptiform discharges (PLEDs), bilateral independent PLEDs or BIPLEDs, generalized epileptiform discharges (GPEDs) and triphasic waves. Stimulus-induced rhythmic, periodic or ictal...

The present paper is a review of counterexamples to the “Hamiltonian Seifert conjecture” or, more generally, of examples of Hamiltonian systems having no periodic orbits on a compact energy level. We begin with the discussion of the “classical” and volume– preserving Seifert conjectures. Then the constructions of counterexamples to the Hamiltonian Seifert conjecture in dimensions greater than o...