Matches in SemOpenAlex for { <https://semopenalex.org/work/W2405962013> ?p ?o ?g. }
Showing items 1 to 81 of
81
with 100 items per page.
- W2405962013 endingPage "182" @default.
- W2405962013 startingPage "1" @default.
- W2405962013 abstract "Many important techniques in image processing rely on partial differential equation (PDE) problems, which exhibit spatial couplings between the unknowns throughout the whole image plane. Therefore, a straightforward spatial splitting into independent subproblems and subsequent parallel solving aimed at diminishing the total computation time does not lead to the solution of the original problem. Typically, significant errors at the local boundaries between the subproblems occur. For that reason, most of the PDE-based image processing algorithms are not directly amenable to coarse-grained parallel computing, but only to fine-grained parallelism, e.g. on the level of the particular arithmetic operations involved with the specific solving procedure. In contrast, Domain Decomposition (DD) methods provide several different approaches to decompose PDE problems spatially so that the merged local solutions converge to the original, global one. Thus, such methods distinguish between the two main classes of overlapping and non-overlapping methods, referring to the overlap between the adjacent subdomains on which the local problems are defined. Furthermore, the classical DD methods --- studied intensively in the past thirty years --- are primarily applied to linear PDE problems, whereas some of the current important image processing approaches involve solving of nonlinear problems, e.g. Total Variation (TV)-based approaches. Among the linear DD methods, non-overlapping methods are favored, since in general they require significanty fewer data exchanges between the particular processing nodes during the parallel computation and therefore reach a higher scalability. For that reason, the theoretical and empirical focus of this work lies primarily on non-overlapping methods, whereas for the overlapping methods we mainly stay with presenting the most important algorithms. With the linear non-overlapping DD methods, we first concentrate on the theoretical foundation, which serves as basis for gradually deriving the different algorithms thereafter. Although we make a connection between the very early methods on two subdomains and the current two-level methods on arbitrary numbers of subdomains, the experimental studies focus on two prototypical methods being applied to the model problem of estimating the optic flow, at which point different numerical aspects, such as the influence of the number of subdomains on the convergence rate, are explored. In particular, we present results of experiments conducted on a PC-cluster (a distributed memory parallel computer based on low-cost PC hardware for up to 144 processing nodes) which show a very good scalability of non-overlapping DD methods. With respect to nonlinear non-overlapping DD methods, we pursue two distinct approaches, both applied to nonlinear, PDE-based image denoising. The first approach draws upon the theory of optimal control, and has been successfully employed for the domain decomposition of Navier-Stokes equations. The second nonlinear DD approach, on the other hand, relies on convex programming and relies on the decomposition of the corresponding minimization problems. Besides the main subject of parallelization by DD methods, we also investigate the linear model problem of motion estimation itself, namely by proposing and empirically studying a new variational approach for the estimation of turbulent flows in the area of fluid mechanics." @default.
- W2405962013 created "2016-06-24" @default.
- W2405962013 creator A5057900904 @default.
- W2405962013 date "2007-01-01" @default.
- W2405962013 modified "2023-09-24" @default.
- W2405962013 title "Variational Domain Decomposition For Parallel Image Processing" @default.
- W2405962013 hasPublicationYear "2007" @default.
- W2405962013 type Work @default.
- W2405962013 sameAs 2405962013 @default.
- W2405962013 citedByCount "0" @default.
- W2405962013 crossrefType "dissertation" @default.
- W2405962013 hasAuthorship W2405962013A5057900904 @default.
- W2405962013 hasConcept C11413529 @default.
- W2405962013 hasConcept C115961682 @default.
- W2405962013 hasConcept C120665830 @default.
- W2405962013 hasConcept C121332964 @default.
- W2405962013 hasConcept C126255220 @default.
- W2405962013 hasConcept C134306372 @default.
- W2405962013 hasConcept C135628077 @default.
- W2405962013 hasConcept C154945302 @default.
- W2405962013 hasConcept C192209626 @default.
- W2405962013 hasConcept C198880260 @default.
- W2405962013 hasConcept C33923547 @default.
- W2405962013 hasConcept C36503486 @default.
- W2405962013 hasConcept C41008148 @default.
- W2405962013 hasConcept C45374587 @default.
- W2405962013 hasConcept C48044578 @default.
- W2405962013 hasConcept C77088390 @default.
- W2405962013 hasConcept C80444323 @default.
- W2405962013 hasConcept C93779851 @default.
- W2405962013 hasConcept C9417928 @default.
- W2405962013 hasConcept C97355855 @default.
- W2405962013 hasConceptScore W2405962013C11413529 @default.
- W2405962013 hasConceptScore W2405962013C115961682 @default.
- W2405962013 hasConceptScore W2405962013C120665830 @default.
- W2405962013 hasConceptScore W2405962013C121332964 @default.
- W2405962013 hasConceptScore W2405962013C126255220 @default.
- W2405962013 hasConceptScore W2405962013C134306372 @default.
- W2405962013 hasConceptScore W2405962013C135628077 @default.
- W2405962013 hasConceptScore W2405962013C154945302 @default.
- W2405962013 hasConceptScore W2405962013C192209626 @default.
- W2405962013 hasConceptScore W2405962013C198880260 @default.
- W2405962013 hasConceptScore W2405962013C33923547 @default.
- W2405962013 hasConceptScore W2405962013C36503486 @default.
- W2405962013 hasConceptScore W2405962013C41008148 @default.
- W2405962013 hasConceptScore W2405962013C45374587 @default.
- W2405962013 hasConceptScore W2405962013C48044578 @default.
- W2405962013 hasConceptScore W2405962013C77088390 @default.
- W2405962013 hasConceptScore W2405962013C80444323 @default.
- W2405962013 hasConceptScore W2405962013C93779851 @default.
- W2405962013 hasConceptScore W2405962013C9417928 @default.
- W2405962013 hasConceptScore W2405962013C97355855 @default.
- W2405962013 hasLocation W24059620131 @default.
- W2405962013 hasOpenAccess W2405962013 @default.
- W2405962013 hasPrimaryLocation W24059620131 @default.
- W2405962013 hasRelatedWork W118625244 @default.
- W2405962013 hasRelatedWork W169367000 @default.
- W2405962013 hasRelatedWork W2030908118 @default.
- W2405962013 hasRelatedWork W2281809292 @default.
- W2405962013 hasRelatedWork W2396047849 @default.
- W2405962013 hasRelatedWork W2409613509 @default.
- W2405962013 hasRelatedWork W2511244214 @default.
- W2405962013 hasRelatedWork W2735379936 @default.
- W2405962013 hasRelatedWork W2770722145 @default.
- W2405962013 hasRelatedWork W2887407209 @default.
- W2405962013 hasRelatedWork W2900284368 @default.
- W2405962013 hasRelatedWork W2964337915 @default.
- W2405962013 hasRelatedWork W2967963851 @default.
- W2405962013 hasRelatedWork W3040586277 @default.
- W2405962013 hasRelatedWork W3083889129 @default.
- W2405962013 hasRelatedWork W3085705715 @default.
- W2405962013 hasRelatedWork W3155052432 @default.
- W2405962013 hasRelatedWork W3197473870 @default.
- W2405962013 hasRelatedWork W908384749 @default.
- W2405962013 hasRelatedWork W2405594267 @default.
- W2405962013 isParatext "false" @default.
- W2405962013 isRetracted "false" @default.
- W2405962013 magId "2405962013" @default.
- W2405962013 workType "dissertation" @default.