Results 41 to 50 of about 174,550,829 (158)
Ergodic theorems for semigroups of operators
We establish ergodic theorems for Eberlein-weakly almost periodic motions and almost-orbits of semigroups of operators. The results apply to solutions of a class of (generally, nonlinear) evolution equations.
W. H. Summers, W. M. Ruess
core +1 more source
KdV limit for the Vlasov–Poisson–Landau system
Abstract We are concerned with the fluid limit to KdV equations for the one‐dimensional Vlasov–Poisson–Landau system that describes the dynamics of ions in plasma with the electron density determined by the self‐consistent electric potential through the so‐called Boltzmann relation. Formally, it is well known that as the Knudsen number ε→0$\varepsilon \
Renjun Duan, Dongcheng Yang, Hongjun Yu
wiley +1 more source
Unary FA-presentable semigroups [PDF]
Automatic presentations, also called FA-presentations, were introduced to extend nite model theory to innite structures whilst retaining the solubility of interesting decision problems.
Cain, Alan James +3 more
core +1 more source
Beyond Regular Semigroups [PDF]
The topic of this thesis is the class of weakly U-abundant semigroups. This class is very wide, containing inverse, orthodox, regular, ample, adequate, quasi-adequate, concordant, abundant, restriction, Ehresmann and weakly abundant semigroups.
Wang, Yanhui
core +4 more sources
Abstract We develop a delay‐aware estimation and control framework for a non‐isothermal axial dispersion tubular reactor modelled as a coupled parabolic‐hyperbolic PDE system with recycle‐induced state delay. The infinite‐dimensional dynamics are preserved without spatial discretization by representing the delay as a transport PDE and adopting a late ...
Behrad Moadeli, Stevan Dubljevic
wiley +1 more source
Long‐Time Solvability and Asymptotics for the 3D Rotating MHD Equations
ABSTRACT We consider the initial value problem for the 3D incompressible rotating MHD equations around a constant magnetic field. We prove the long‐time existence and uniqueness of solutions for small viscosity coefficient and high rotating speed. Moreover, we investigate the asymptotic behavior of solutions in the limit of vanishing viscosity and fast
Hiroki Ohyama
wiley +1 more source
From Stability to Chaos: A Complete Classification of the Damped Klein‐Gordon Dynamics
ABSTRACT We investigate the transition between stability and chaos in the damped Klein‐Gordon equation, a fundamental model for wave propagation and energy dissipation. Using semigroup methods and spectral criteria, we derive explicit thresholds that determine when the system exhibits asymptotic stability and when it displays strong chaotic dynamics ...
Carlos Lizama +2 more
wiley +1 more source
Semigroups of order-decreasing transformations [PDF]
Let X be a totally ordered set and consider the semigroups of orderdecreasing (increasing) full (partial, partial one-to-one) transformations of X. In this Thesis the study of order-increasing full (partial, partial one-to-one) transformations has been
Umar, Abdullahi
core +2 more sources
Spreading Speed for a Vector‐Borne Disease System on Non‐Coincident Straight Infinite Cylinders
ABSTRACT Vector‐borne diseases remain an increasing global public health concern. In this work, we investigate the spreading speed of vector‐borne disease via a four‐component reaction–diffusion system posed on non‐coincident straight infinite cylinders, which stands for an unconventional spatial configuration.
Arnaud Ducrot +2 more
wiley +1 more source
Existence of viscosity solutions to abstract Cauchy problems via nonlinear semigroups
Abstract In this work, we provide conditions for nonlinear monotone semigroups on locally convex vector lattices to give rise to a generalized notion of viscosity solutions to a related nonlinear partial differential equation. The semigroup needs to satisfy a convexity estimate, so called K$K$‐convexity, with respect to another family of operators ...
Fabian Fuchs, Max Nendel
wiley +1 more source

