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Reduction from three-dimensional discrete tomography to multicommodity flow problem

Y. Gerard
2005 Theoretical Computer Science  
We extend this result in dimension 3 by reducing three-dimensional discrete tomography to multicommodity flow problems.  ...  The reduction from two-dimensional-discrete tomography to max-flow problem is well-known [Gale, A theorem on flows in networks, Pacific J. Math. 7 (1957) 1073-1082].  ...  This correspondence provides a reduction from two-dimensional-discrete tomography to flow-max problem (Fig. 2) .  ... 
doi:10.1016/j.tcs.2005.08.016 fatcat:pfca4cf2i5g6hcthqicfmeezqy

Author index

2005 Theoretical Computer Science  
Herman, Implicit surface visualization of reconstructed biological molecules (2-3) 281-299 Gerard, Y., Reduction from three-dimensional discrete tomography to multicommodity flow problem (2-3) 300-306  ...  Noy, A solution to the tennis ball problem (2-3) 254-264 del Mar Gallardo, M., see M. Alpuente (1) 58-95 Di Pierro, A., see A. Cerone (1) 1-2 Epifanio, C. and F.  ... 
doi:10.1016/s0304-3975(05)00741-3 fatcat:l5tz2ivssreuzg56qjcrhv7pkq

Reports about new techniques for the integration of model hierarchies into optimization techniques

Andreas Bärmann, Alexander Martin, Jonasz Staszek, Jean-David Benamou, Giorgi Rukhaia, Ronny Ramlau, Bernadett Stadler, Wilbert Ijzerman, Michael Hintermüller, Karl Knall, Hong Nguyen
2021 Zenodo  
They then use large-scale neighborhood search techniques to come up with good-quality solution. Basing on multicommodity flow problem, Cordeau et al.  ...  Then, based on some examples from the literature, we construct a model which corresponds to the state of the art. We use multi-commodity flow formulation for this problem.  ...  Cost functionals and a shape optimization problem The uniformity of the flow leaving the outlet is an important design criterion of automotive air ducts to enhance the efficiency of distributing the air  ... 
doi:10.5281/zenodo.5347697 fatcat:gfukdxnphbhyviypzrybjdi3xm

Diffraction by image processing and its application in materials science

Joachim Ohser, Katja Schladitz, Karsten Koch, Michael Nöthe
2005 Zeitschrift für Metallkunde  
It is shown that the fast Fourier transform applied to three-dimensional images of microstructures obtained by micro-tomography is a powerful tool of image processing.  ...  tomography (µCT), see [10], [15] ).  ...  The authors are grateful to the Deutsche Forschungsgemeinschaft (Oh 59/5-1) for financial support. We are indepted to T. Sych for producing the visualizations of the sinter material.  ... 
doi:10.3139/146.101094 fatcat:zjvl7coqqrfatgaxw65twc4vh4

Application of general semi-infinite programming to lapidary cutting problems

Anton Winterfeld
2008 European Journal of Operational Research  
Lower level problems and Stackelberg games. The optimal solution of a general semi-infinite problem is closely related to its lower level problems, which have the form:  ...  An iterative process consisting of GSIP optimization and adaptive refinement steps is then employed to obtain an optimal solution which is also feasible for the original problem.  ...  It is shown that the fast Fourier transform applied to three-dimensional images of microstructures obtained by micro-tomography is a powerful tool of image processing. H.  ... 
doi:10.1016/j.ejor.2007.01.057 fatcat:6szzfosbgngsbhzmqpc3xac6ry

Design of acoustic trim based on geometric modeling and flow simulation for non-woven

Katja Schladitz, Stefanie Peters, Doris Reinel-Bitzer, Andreas Wiegmann, Joachim Ohser
2006 Computational materials science  
In the present application, the anisotropy parameter has to be estimated from 2d reflected light microscopic images of microsections of the non-woven.  ...  Finally, the set of parameters for the geometric model leading to the best acoustic absorption is chosen.  ...  Acknowledgment We thank Hans-Karl Hummel for his contribution to developing the estimation procedure, Oliver Wirjadi for segmenting the fibers, and Tetjana Sych for the 3d visualizations.  ... 
doi:10.1016/j.commatsci.2006.01.018 fatcat:oytmwjxww5cohhdbreybdjqc24

SOLVING SPARSE TRIANGULAR LINEAR SYSTEMS ON PARALLEL COMPUTERS

EDWARD ANDERSON, YOUCEF SAAD
1989 International journal of high speed computing  
It would not have been possible for me to have finished the program without lots of help from friends.  ...  The list is far too long to detail here, but I would especially like to thank Doug Reece for all the time spent listening to my troubles on long runs through Schenley Park.  ...  In this set of experiments, we extended the two-dimensional problem from section 6.1.1 into three dimensions.  ... 
doi:10.1142/s0129053389000056 fatcat:pqjsiyvz3zbnniienbqzcuj6t4

Comparison of the solutions of the elastic and elastoplastic boundary value problems

Holger Lang, Klaus Dressler, René Pinnau, Michael Speckert
2009 Zeitschrift für Angewandte Mathematik und Physik  
To this end, we use the stop and play operators of nonlinear functional analysis. Further, we give an explicit example of a homotopy between the solutions of both problems.  ...  kinematic hardening law for the plastic regime in the latter problem.  ...  Brokate (TU München) and René Pinnau (TU Kaiserslautern) for scientific support and to our whole MDF group, in particular to Ilker Nikelay, Albert Marquardt, Thorsten Weyh and Sabrina Herkt.  ... 
doi:10.1007/s00033-009-0042-y fatcat:z7y3ihyzzzasdd4geqqyqwdwvi

Mathematics as a Technology–Challenges for the next Ten Years [chapter]

H Neunzert
2005 Lecture Notes in Pure and Applied Mathematics  
Lang Padé-like reduction of stable discrete linear systems preserving their stability A new stability preserving model reduction algorithm for discrete linear SISO-systems based on their impulse response  ...  Two are so-called "inverse problems": To measure the temperature in the interior of the glass flow from radiation and to optimize the shape of the flanges carrying the pipe such that a given homogeneous  ...  It is shown that the fast Fourier transform applied to three-dimensional images of microstructures obtained by micro-tomography is a powerful tool of image processing.  ... 
doi:10.1201/9781420026511.pt1 fatcat:c6ni6noa3nambgkuftojudjbem

On a multigrid solver for the three-dimensional Biot poroelasticity system in multilayered domains

A. Naumovich, F. J. Gaspar
2007 Computing and Visualization in Science  
In this paper, we present problem-dependent prolongation and problem-dependent restriction for a multigrid solver for the three-dimensional Biot poroelasticity system, which is solved in a multilayered  ...  The system is discretized on a staggered grid using the finite volume method. During the discretization, special care is taken of the discontinuous coefficients.  ...  It is shown that the fast Fourier transform applied to three-dimensional images of microstructures obtained by micro-tomography is a powerful tool of image processing. H.  ... 
doi:10.1007/s00791-007-0059-8 fatcat:tjazta2djfhjfdxdm42au7rbfu

A new algorithm for topology optimization using a level-set method

Samuel Amstutz, Heiko Andrä
2006 Journal of Computational Physics  
The level-set method has been recently introduced in the field of shape optimization, enabling a smooth representation of the boundaries on a fixed mesh and therefore leading to fast numerical algorithms  ...  However, most of these algorithms use a Hamilton-Jacobi equation to connect the evolution of the level-set function with the deformation of the contours, and consequently they cannot create any new holes  ...  The authors are grateful to Oleg Iliev for his valuable help concerning Section 5.  ... 
doi:10.1016/j.jcp.2005.12.015 fatcat:2ip4frr5sjh6dlfq5zqy5odopi

Benchmark cases

Marcus Bannenberg, Andreas Bärmann, Patricia Barral, Jean-David Benamou, Federico Bianco, Andres Binder, Guillaume Chazareix, Angelo Ciccazzo, Ricardo Conte, Daniel Fernandez Comesana, Michele Girfoglio, Michael Günther (+19 others)
2021 Zenodo  
compatibility, conflict and multiple-choice constraints and a multicommodity flow problem.  ...  More precisely, the GitHub repository includes all the data and Python scripts to run from scratch the following three coupled problems: • A three-dimensional coupled fluid-PML acoustic scattering problem  ...  Simulation -Restart In case of running error, a restart procedure has to be carried over to continue the simulation from the last saved timestep.  ... 
doi:10.5281/zenodo.5379396 fatcat:37swxkcsundwra5oiaahd664zq

Further Research on Node Based Bottleneck Improvement Problem for Multicut [chapter]

Xiucui Guan, Jie Su
2006 Lecture Notes in Computer Science  
This conference gives researchers an opportunity to present their latest results and to discuss current developments and applications, besides stimulating future interactions between the members of this  ...  ECCO wants to provide a forum for researchers in combinatorial optimization, either in its theoretical aspects or in business, industry or public administration applications.  ...  The p-Center problem consists in locating p facilities among a set of M possible locations and assigning N clients to them in order to minimize the maximum distance between a client and the facility to  ... 
doi:10.1007/11816157_107 fatcat:xjdnf4kesrbczoh4ilvxxixqei

On efficient simulation of non-Newtonian flow in saturated porous media with a multigrid adaptive refinement solver

Oleg Iliev, Daniela Vassileva, Dimitar Stoyanov, Willy Dörfler
2008 Computing and Visualization in Science  
Results from numerical solution of various academic and practice-induced problems are presented and the performance of the solver is discussed.  ...  A special implementation approach is used, which allows us to perform unstructured local refinement in conjunction with the finite volume discretization.  ...  Vassileva acknowledges the fellowship from European Research Consortium for Informatics and Mathematics (ERCIM) for her work at ITWM, Kaiserslautern.  ... 
doi:10.1007/s00791-008-0119-8 fatcat:5wjtllasmndfng4saoontq3csy

IMRT planning on adaptive volume structures—a decisive reduction in computational complexity

Alexander Scherrer, Karl-Heinz Küfer, Thomas Bortfeld, Michael Monz, Fernando Alonso
2005 Physics in Medicine and Biology  
Special thanks are adressed to Christian Thieke and Uwe Oelfke for a long lasting teamwork and to Christoph Thilmann for the helpful consulting in clinical questions.  ...  Acknowledgments The authors are grateful to the members of the Department of Medical Physics in Radiation Oncology of Wolfgang Schlegel and the Clinical Cooperation Unit Radiation Oncology of Jürgen Debus  ...  This accumulates to a high computational expense due to the large scale of these problems -a consequence of the discrete problem formulation.  ... 
doi:10.1088/0031-9155/50/9/008 pmid:15843735 fatcat:bpuaww5hyvc6pablvyf5mqa3ky
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