Results 271 to 280 of about 3,418,189 (307)

Equations in predicates and their extreme solutions

1990
In the previous chapter we have encountered a number of statements S for which the predicate transformers wlp.S and wp.S were given in closed form. In the next chapter we shall encounter the statement DO, for which the predicates wlp.DO.X and wp.DO.X will be defined as solutions of equations of the ...
Edsger W. Dijkstra, Carel S. Schölten
openaire   +1 more source

Extremal solutions of classes of multivalued differential equations

Applied Mathematics and Computation, 2003
The paper is concerned with the existence of extremal solutions to a class of multivalued boundary value problems and evolution inclusion with m-accretive operators. Recently, similar problems have been considered in many papers. For example, more deeper results of such kind can be found in the book by \textit{Sh. Hu} and \textit{N. S.
Ahmed Gamal Ibrahim, A. G. Gomaa
openaire   +3 more sources

On the Components of Extremal Solutions of Second Order Systems

SIAM Journal on Mathematical Analysis, 1977
Sign properties of components of extremal solutions of the linear system \[ x'' + A(t)x = 0, \] where $A(t)$ is a continuous $n \times n$ matrix, are investigated. For most of the considerations, $A(t)$ is assumed to be symmetric. The proofs are based on variational arguments.
Ahmad, Shair, Lazer, Alan C.
openaire   +1 more source

Solution of an extremal problem in operator theory

1983
Let \(E_ 1,E_ 2\) be normed linear spaces of 2\(\pi\)-periodic integrable functions, \(\Pi_ n\) be the set of all trygonometric polynomials of the order \(\leq n\). The author gives a complete solution of the problem of constructing an extremal operator in the class \(\Omega_ n^{(k)}\) of all linear operators \(u_ n(f,x):E_ 1\to E_ 2\) such that \(u_ n(
openaire   +2 more sources

Bioenergetics and solute uptake under extreme conditions

Extremophiles, 2001
The ion and particularly the proton and sodium ion permeabilities of cytoplasmic membranes play crucial roles in the bioenergetics of microorganisms. The proton and sodium permeabilities of membranes increase with temperature. Psychrophilic and mesophilic bacteria and mesophilic, (hyper)thermophilic, and halophilic archaea are capable of adjusting the ...
Albers, Sonja Verena, Vossenberg, Jack L., Driessen, Arnold J. M., Konings, Wil N.   +3 more
openaire   +4 more sources

Extremal Solutions in the Marginal Problem

1991
This is a review paper collecting both older and recent progress in the field of twodimensional marginal problem concerning the extreme points of the set of solutions. Some new results in the characterization of extremal solutions are presented in Section 5.
Viktor Benes, Josef Stepan
openaire   +1 more source

Existence of solutions of extremal problems

Cybernetics and Systems Analysis, 1995
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +1 more source

Extremal solutions and extremal norms of linear differential inclusions of order three

Proceedings of the 45th IEEE Conference on Decision and Control, 2006
Linear differential inclusions arising in the theory of absolute stability of feedback systems with two time-varying sector nonlinearities are considered. It is shown that under controllability/observability assumptions in the case of zero Lyapunov exponent all the extremal solutions tend to the same (up to a positive scaling factor) antiperiodic ...
openaire   +1 more source

Extremal solutions to a class of functional-differential equations

1997
The authors study, under Carathéodory assumptions, the existence, continuation and continuous dependence of extremal solutions to a general abstract class of hereditary differential equations of the form \(\dot{x}=g(t,x)\), \(t\in E\subset{\mathbb{R}}\), with some Volterra property assumed on \(g:E\times C(E)\rightarrow \mathbb{R}\).
CEPPITELLI, Rita, FAINA, Loris
openaire   +3 more sources

Extremal Solutions of Multivalued Differential Equations II

Results in Mathematics, 1989
Given a cone \(K\subset\mathbb{R}^ n\) and a set-valued differential equation \(\dot x\in F(t,x)\), \(t\in J=[0,a]\), the author wants to find an absolutely continuous solution which is minimal with respect to the ordering induced by \(K\). The assumptions on \(F\) are the following: (1) \(\| F(t,x)\|\leq c(t)(1+\| x\|)\), \(c\in L^ 1(J)\); (2) \(f(t,x)
openaire   +2 more sources