Title:
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A sequential iteration algorithm with non-monotoneous behaviour in the method of projections onto convex sets (English) |
Author:
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Crombez, G. |
Language:
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English |
Journal:
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Czechoslovak Mathematical Journal |
ISSN:
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0011-4642 (print) |
ISSN:
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1572-9141 (online) |
Volume:
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56 |
Issue:
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2 |
Year:
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2006 |
Pages:
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491-506 |
Summary lang:
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English |
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Category:
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math |
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Summary:
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The method of projections onto convex sets to find a point in the intersection of a finite number of closed convex sets in a Euclidean space, may lead to slow convergence of the constructed sequence when that sequence enters some narrow “corridor” between two or more convex sets. A way to leave such corridor consists in taking a big step at different moments during the iteration, because in that way the monotoneous behaviour that is responsible for the slow convergence may be interrupted. In this paper we present a technique that may introduce interruption of the monotony for a sequential algorithm, but that at the same time guarantees convergence of the constructed sequence to a point in the intersection of the sets. We compare experimentally the behaviour concerning the speed of convergence of the new algorithm with that of an existing monotoneous algorithm. (English) |
Keyword:
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projections onto convex sets |
Keyword:
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nonlinear operators |
Keyword:
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slow convergence |
MSC:
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40A99 |
MSC:
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47H09 |
MSC:
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47H10 |
MSC:
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47N10 |
MSC:
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49M30 |
MSC:
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52A20 |
MSC:
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90C25 |
idZBL:
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Zbl 1164.47399 |
idMR:
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MR2291750 |
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Date available:
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2009-09-24T11:34:47Z |
Last updated:
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2020-07-03 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/128080 |
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Reference:
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Reference:
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