scholarly journals On the construction of convergent iterative sequences of polynomials

Author(s):  
Qiu Weiyuan

AbstractWe answer two conjectures suggested by Zalman Rubinstein. We prove his Conjecture 1, that is, we construct convergent iterative sequences for with an arbitrary initial point, where with m ≥ 2. We also show by several counterexamples that Rubinstein's Conjecture 2 is generally false.

Author(s):  
V I Korobov ◽  
T V Revina

Abstract The feedback synthesis problem for a chain of integrators system with continuous bounded unknown perturbation is considered. Our approach is based on the controllability function (CF) method proposed by V.I. Korobov. The perturbation range is determined by the negativity condition for the total derivative of the CF with respect to the perturbed system. The control that does not depend on perturbation under some restrictions and steers an arbitrary initial point from a neighborhood of the origin to the origin in a finite time (settling-time function) is constructed. The settling-time function depends on the perturbation, but it remains bounded from below and from above by the same value.


2012 ◽  
Vol 2012 ◽  
pp. 1-20 ◽  
Author(s):  
Lu-Chuan Ceng ◽  
Ching-Feng Wen

Assume thatFis a nonlinear operator which is Lipschitzian and strongly monotone on a nonempty closed convex subsetCof a real Hilbert spaceH. Assume also thatΩis the intersection of the fixed point sets of a finite number of Lipschitzian pseudocontractive self-mappings onC. By combining hybrid steepest-descent method, Mann’s iteration method and projection method, we devise a hybrid iterative algorithm with perturbationF, which generates two sequences from an arbitrary initial pointx0∈H. These two sequences are shown to converge in norm to the same pointPΩx0under very mild assumptions.


1990 ◽  
Vol 2 (4) ◽  
pp. 303-307
Author(s):  
Hisato Kobayashi ◽  
◽  
Katsuhiko Inagaki

This article describes an example using a neural net as a method of mobile robot operation. The method eliminates the need for characteristic equations of a mobile robot, but requires an exercise to some extent using adequate ""patterns."" For accumulating experience of this practice, an RCE (restricted coulomb energy) network, or a pattern recognition-use neural network, is used. A simulation is conducted by driving a car into a garage. A man drives a car into a garage to create pattern data, which an RCE net is made to learn. After learning to some extent, it is allowed to put a car into a garage from an arbitrary initial point. The following are the descriptions of the results.


1980 ◽  
Vol 101 (2) ◽  
pp. 349-376 ◽  
Author(s):  
Jon Lee

To resolve possible fluctuations about the mean motion of the Desnyansky-Novikov model for Kolmogorov's inertial flow, we have investigated two dynamical systems of the cascade process which are formally derivable from Burgers’ equation. The first cascade model produced no fluctuations, for its trajectory was identical with the Desnyansky–Novikov model's. Disappointingly, the second cascade system, which is similar to the Kerr–Siggia model, has also proved unable to engender fluctuations. This is because the second model when truncated consistently maps an arbitrary initial point into the attainable phase space of the first cascade model. However, when truncated inconsistently the trajectory of second model can exhibit a quite erratic and somewhat sporadic motion, thereby reflecting the apparently random motion of inviscid equilibrium solutions. Therefore, the observation of temporally intermittent fluctuations by a stationary Kerr–Siggia model is due to the inconsistent truncation produced by restricting energy dissipation for all but the upper truncation mode in their model.


Author(s):  
А.Н. Громов

Предложен метод отыскания нулей целых функций конечного порядка, который сходится к корню от произвольной начальной точки, т.е. является глобально сходящимся. Метод основан на представлении производных высшего порядка от логарифмической производной в виде суммы простейших дробей и сводит отыскание корня к выбору минимального числа из конечного множества. Даны оценки скорости сходимости. A method for finding zeros of integer functions of finite order is proposed. This method converges to a root starting from an arbitrary initial point and, hence, is globally convergent. The method is based on a representation of higher-order derivatives of the logarithmic derivative as a sum of partial fractions and reduces the finding of a root to the choice of the minimum number from a finite set. The rate of convergence is estimated.


Author(s):  
Zalman Rubinstein

AbstractConvergent iterative sequences are constructed for the polynomials fm = z + zm, m ≧ 2, with initial point the lemniscate {z: |fm (z)| ≦1}. In the particular case m = 2 convergent iterative sequences are constructed also for f-1m, (z) with an arbitrary initial point. The method is based on a certain variational principle which allows reducing the problem to the well known situation of an analytic function mapping a simply connected domain into a proper subset of itself and possessing a fixed point in the domain.


2008 ◽  
Vol 2 (2) ◽  
pp. 197-204 ◽  
Author(s):  
Yu Miao ◽  
Li Junfen

In a real Hilbert space H, starting from an arbitrary initial point x0 H, an iterative process is defined as follows: xn+1 = anxn +(1-an)T?n+1 f yn, yn = bnxn + (1 - bn)T?n g xn, n ? 0, where T ?n+1 f x = Tx - ?n+1?f f(Tx), T?n g x = Tx - ?n?gg(Tx), (8 x 2 H), T : H ? H a nonexpansive mapping with F(T) 6= ; and f (resp. g) : H ? H an ?f (resp. ?g)-strongly monotone and kf (resp. kg)-Lipschitzian mapping, {an} _ (0, 1), {bn} _ (0, 1) and {?n} _ [0, 1), {?n} _ [0, 1). Under some suitable conditions, several convergence results of the sequence {xn} are shown.


Sign in / Sign up

Export Citation Format

Share Document