東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Efficient controls for finitely conv...

Chen, Wei.

Linked to FindBook

Google Book

Amazon

博客來

Efficient controls for finitely convergent sequential algorithms and their applications.

Record Type:	Language materials, printed : Monograph/item
Title/Author:	Efficient controls for finitely convergent sequential algorithms and their applications./
Author:	Chen, Wei.
Description:	109 p.
Notes:	Source: Dissertation Abstracts International, Volume: 71-07, Section: B, page: 4338.
Contained By:	Dissertation Abstracts International71-07B.
Subject:	Applied Mathematics. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3409145
ISBN:	9781124062969

Efficient controls for finitely convergent sequential algorithms and their applications.
Chen, Wei.

Efficient controls for finitely convergent sequential algorithms and their applications. - 109 p.

Source: Dissertation Abstracts International, Volume: 71-07, Section: B, page: 4338.

Thesis (Ph.D.)--City University of New York, 2010.

Finding a feasible point that satisfies a set of constraints or a point that optimizes a function subject to a set of constraints is a common task in scientific computing: examples are the linear/convex feasibility/optimization problems. Projection methods have been used widely in solving many such problems of large size much more efficiently than other alternatives. Finitely convergent sequential algorithms are projection methods that sequentially iterate on individual constraints, one at a time, but overall find a feasible point in a finite number of iterations. ART3 is an example using cyclic control in the sense that it repeatedly cycles through the given constraints. The skipping unnecessary checks on constraints that are likely to be satisfied, lead to the new algorithm ART3+, a variant of ART3 whose control is no longer cyclic, but which is still finitely convergent. Experiments in fitting pixel images by blob images show that ART3+ is statistically significantly faster than ART3. Furthermore, a general methodology is proposed for automatic transformation of any finitely convergent sequential algorithm in such a way that (1) finite convergence is retained and (2) the speed of finite convergence is improved. The first property is proved by mathematical theorems, the second is illustrated by applying the algorithms to practical problems. This transformation is applicable, for example, to the finitely convergent modified cyclic subgradient projection algorithm for solving convex feasibility problems.

ISBN: 9781124062969Subjects--Topical Terms:

1669109
Applied Mathematics.

Efficient controls for finitely convergent sequential algorithms and their applications.
LDR:03374nam 2200325 4500 001 1399871
005 20110930095855.5
008 130515s2010 ||||||||||||||||| ||eng d
020 $a 9781124062969
035 $a (UMI)AAI3409145
035 $a AAI3409145
040 $a UMI $c UMI
100 1 $a Chen, Wei. $3 1064731
245 1 0 $a Efficient controls for finitely convergent sequential algorithms and their applications.
300 $a 109 p.
500 $a Source: Dissertation Abstracts International, Volume: 71-07, Section: B, page: 4338.
500 $a Adviser: Gabor T. Herman.
502 $a Thesis (Ph.D.)--City University of New York, 2010.
520 $a Finding a feasible point that satisfies a set of constraints or a point that optimizes a function subject to a set of constraints is a common task in scientific computing: examples are the linear/convex feasibility/optimization problems. Projection methods have been used widely in solving many such problems of large size much more efficiently than other alternatives. Finitely convergent sequential algorithms are projection methods that sequentially iterate on individual constraints, one at a time, but overall find a feasible point in a finite number of iterations. ART3 is an example using cyclic control in the sense that it repeatedly cycles through the given constraints. The skipping unnecessary checks on constraints that are likely to be satisfied, lead to the new algorithm ART3+, a variant of ART3 whose control is no longer cyclic, but which is still finitely convergent. Experiments in fitting pixel images by blob images show that ART3+ is statistically significantly faster than ART3. Furthermore, a general methodology is proposed for automatic transformation of any finitely convergent sequential algorithm in such a way that (1) finite convergence is retained and (2) the speed of finite convergence is improved. The first property is proved by mathematical theorems, the second is illustrated by applying the algorithms to practical problems. This transformation is applicable, for example, to the finitely convergent modified cyclic subgradient projection algorithm for solving convex feasibility problems.
520 $a One application is to intensity modulated radiation therapy (IMRT), whose goal is to deliver sufficient doses to tumors to kill them, but without causing irreparable damage to critical organs. The superior performance of the ART3+ for IMRT is demonstrated. An optimization algorithm based on ART3+ is proposed to handle linear constraints with either linear objectives or certain convex objectives. It is on average more than two orders of magnitude faster than the state of art industry-standard commercial algorithms (MOSEK's interior point optimizer and primal/dual simplex optimizer) and has almost no memory overhead. This allows for fast creation of multi-criteria treatment plan databases that span the global planning options available to the treatment planner.
590 $a School code: 0046.
650 4 $a Applied Mathematics. $3 1669109
650 4 $a Computer Science. $3 626642
690 $a 0364
690 $a 0984
710 2 $a City University of New York. $b Computer Science. $3 1029886
773 0 $t Dissertation Abstracts International $g 71-07B.
790 1 0 $a Herman, Gabor T., $e advisor
790 1 0 $a Haralick, Robert M. $e committee member
790 1 0 $a Bar-Noy, Amotz $e committee member
790 1 0 $a Bortfeld, Thomas $e committee member
790 $a 0046
791 $a Ph.D.
792 $a 2010
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3409145