Publikationen SGS: Bibliographie 2003 BibTeX
@inproceedings {INPROC-2003-41,
author = {Ralf-Peter Mundani and Hans-Joachim Bungartz and Ernst Rank and Richard Romberg and Andreas Niggl},
title = {{Efficient Algorithms for Octree-Based Geometric Modelling}},
booktitle = {Proceedings of the Ninth International Conference on Civil and Structural Engineering Computing: CC '03; Egmond aan Zee, The Netherlands, September 2-4, 2003},
editor = {B.H.V. Topping},
publisher = {Civil-Comp Press},
institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
type = {Konferenz-Beitrag},
month = {September},
year = {2003},
keywords = {octrees; volume-oriented geometric modelling; consistency checks; hierarchical data structures; on-the-fly generation; embedded simulation},
language = {Englisch},
cr-category = {I.3.5 Computational Geometry and Object Modeling,
I.6.0 Simulation and Modeling General,
I.6.3 Simulation and Modeling Applications,
J.2 Physical Sciences and Engineering,
J.6 Computer-Aided Engineering},
contact = {Ralf-Peter Mundani Ralf.Mundani@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {Dealing with surface-oriented models - e.g. B-Rep models - is very popular and
appropriate for many applications. They can be read by most CAD programs and
they provide all freedom of modelling. Concerning a lot of other tasks -
consistency checks, collision detection, structural analysis, flow simulation,
e.g. - these models become difficult to handle, and a volume-oriented model has
to be derived from the existing surface-oriented one. Hierarchical
volume-oriented models, represented by octrees for example, provide an easy
access to solve the latter tasks with respect to their spatial decomposition of
the underlying geometry. This paper deals with fast and efficient algorithms to
generate and process octrees - even on-the-fly - from surface-oriented models
for applications in civil engineering. Encoding these octrees as binary streams
makes them suitable to get multiplexed with other octree-coded objects or for
the usage in pipe-like constructs.
Conventional algorithms for octree generation or processing don't exploit the
full potential of these structures. In spite of the principal advantages of
octrees concerning complexity, objects of a higher resolution typically still
entail too high run-time and memory requirements. Usually, an expensive
floating-point-based decision whether or not to refine the structure has to be
taken in each voxel (cell) successively. In our approach, instead, the
refinement decision is done by a simple parameter comparison of plane
equations, avoiding all these costs.
By treating each face of the surface-oriented model as a plane that divides the
whole space into two half spaces - inside and outside -, the volume-oriented
model can be built from intersecting all inside-attributed half spaces. The
steps for generating an octree presentation for each corresponding plane,
intersecting these octrees, and encoding the result as a binary stream can be
done at once - thus, the octree generation is free of any redundant
calculations, and the overall memory requirements are reduced to a minimum due
to the usage of stacks. The highest gain can be achieved in run-time, e.g. an
octree generation for an average geometry with more than 1.5 billion voxels can
be done in best time on a standard PC. Several of these binary streams can be
multiplexed to perform further Boolean or more sophisticated operations (e.g.
collision detection), while one always has the choice to perform this
operations on-the-fly or to perform consecutive operations - like with Unix
pipes - on binary streams written to the hard disk.
One target application of this method deals with consistency checks for CAD
models in the scope of simplifying and unifying planning processes in civil
engineering. Before a connection model for structural analysis is created out
of an (Eurostep) IFC model, any modelling errors (geometric inconsistencies) -
wrong intersections or gaps between parts of the model - can be detected fast
and easily. Hence, this proceeding enables us to obtain a reliable
volume-oriented attributed model that can serve for numerical simulations as
well as to determine relations between parts of the model to ensure global
consistency, which brings us one step closer to the long-term objective of
completely embedded simulation processes.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2003-41&engl=0}
}
@article {ART-2003-08,
author = {Hans-Joachim Bungartz},
title = {{Sparse Grids - Tackling the Curse of Dimension}},
journal = {gacm Report},
publisher = {gacm},
volume = {2003},
number = {2},
pages = {16--21},
type = {Artikel in Zeitschrift},
month = {Januar},
year = {2003},
language = {Englisch},
cr-category = {G.1 Numerical Analysis},
contact = {Hans-Joachim Bungartz bungartz@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {no abstract available},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2003-08&engl=0}
}
@article {ART-2003-07,
author = {Hans-Joachim Bungartz},
title = {{Computational Science and Engineering: a new master's program at the Technische Universit{\"a}t M{\"u}nchen}},
journal = {Future Generation Computer Systems},
address = {Amsterdam},
publisher = {Elsevier B.V.},
volume = {19},
number = {8},
pages = {1267--1274},
type = {Artikel in Zeitschrift},
month = {November},
year = {2003},
language = {Englisch},
cr-category = {K.3 Computers and Education},
contact = {Hans-Joachim Bungartz bungartz@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {In the winter semester of 2001/2002, the Technische Universit{\"a}t M{\"u}nchen (TUM)
started its new master's program computational science and engineering (CSE) as
a joint initiative of seven faculties. It is the objective of this contribution
to outline the underlying ideas and concepts and their curricular
implementation as well as to emphasize some features that are probably
non-standard in other comparable programs.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2003-07&engl=0}
}
@article {ART-2003-06,
author = {Hans-Joachim Bungartz and Stefan Dirnstorfer},
title = {{Multivariate quadrature on adaptive sparse grids}},
journal = {Computing},
address = {New York},
publisher = {Springer},
volume = {71},
number = {1},
pages = {89--114},
type = {Artikel in Zeitschrift},
month = {September},
year = {2003},
isbn = {0010-485X},
language = {Englisch},
cr-category = {G.1 Numerical Analysis,
I.1 Symbolic and Algebraic Manipulation},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {In this paper, we study the potential of adaptive sparse grids for multivariate
numerical quadrature in the moderate or high dimensional case, i.e. for a
number of dimensions beyond three and up to several hundreds. There,
conventional methods typically suffer from the curse of dimension or are
unsatisfactory with respect to accuracy. Our sparse grid approach, based upon a
direct higher order discretization on the sparse grid, overcomes this dilemma
to some extent, and introduces additional flexibility with respect to both the
order of the 1 D quadrature rule applied (in the sense of Smolyak's tensor
product decomposition) and the placement of grid points. The presented
algorithm is applied to some test problems and compared with other existing
methods.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2003-06&engl=0}
}
@inbook {INBOOK-2003-17,
author = {Hans-Joachim Bungartz and Miriam Mehl},
title = {{Biofilms in Wastewater Treatment: An Interdisciplinary Approach}},
series = {Beyond models: Requirements and chances of computational biofilms},
publisher = {IWA Publishing},
pages = {60--87},
type = {Beitrag in Buch},
month = {Januar},
year = {2003},
language = {Englisch},
cr-category = {I.6 Simulation and Modeling},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {The central theme of the book is the flow of information from experimental
approaches in biofilm research to simulation and modeling of complex wastewater
systems. Probably the greatest challenge in wastewater research lies in using
the methods and the results obtained in one scientific discipline to design
intelligent experiments in other disciplines, and eventually to improve the
knowledge base the practitioner needs to run wastewater treatment plants. The
purpose of Biofilms in Wastewater Treatment is to provide engineers with the
knowledge needed to apply the new insights gained by researchers. The authors
provide an authoritative insight into the function of biofilms on a technical
and on a lab-scale, cover some of the exciting new basic microbiological and
wastewater engineering research involving molecular biology techniques and
microscopy, and discuss recent attempts to predict the development of biofilms.
This book is divided into 3 sections: Modeling and Simulation; Architecture,
Population Structure and Function; and From Fundamentals to Practical
Application, which all start with a scientific question. Individual chapters
attempt to answer the question and present different angles of looking at
problems. In addition there is an extensive glossary to familiarize the
non-expert with unfamiliar terminology used by microbiologists and
computational scientists.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2003-17&engl=0}
}
@inbook {INBOOK-2003-16,
author = {Hans-Joachim Bungartz and M. Kuehn and Miriam Mehl and S. Wuertz},
title = {{Polymer and Cell Dynamics - Multiscale Modelling and Numerical Simulations}},
series = {Space- and time-resolved simulations of processes in biofilm systems on a microscale},
address = {Basel},
publisher = {Birkh{\"a}user},
pages = {175--188},
type = {Beitrag in Buch},
month = {Oktober},
year = {2003},
isbn = {376-436-924-8},
language = {Deutsch},
cr-category = {I.6 Simulation and Modeling},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {leer},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2003-16&engl=0}
}
@inbook {INBOOK-2003-08,
author = {H.-J. Bungartz and M. Mehl},
title = {{Beyond models: Requirements and chances of computational biofilms}},
series = {Biofilms in Wastewater Treatment: An Interdisciplinary Approach},
publisher = {IWA Publishing},
pages = {60--87},
type = {Beitrag in Buch},
month = {Januar},
year = {2003},
language = {Englisch},
cr-category = {J.3 Life and Medical Sciences},
contact = {Hans-Joachim Bungartz bungartz@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {no abstract available},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2003-08&engl=0}
}
@inbook {INBOOK-2003-07,
author = {Hans-Joachim Bungartz and M. Kuehn and M. Mehl and S. Wuertz},
title = {{Space- and time-resolved simulations of processes in biofilm systems on a microscale}},
series = {Polymer and Cell Dynamics - Multiscale Modelling and Numerical Simulations},
address = {Basel},
publisher = {Birkh{\"a}user},
pages = {175--188},
type = {Beitrag in Buch},
month = {Oktober},
year = {2003},
isbn = {3764369248},
language = {Englisch},
cr-category = {J.3 Life and Medical Sciences,
I.6 Simulation and Modeling},
contact = {Hans-Joachim Bungartz bungartz@ipvs.uni-stuttgart.de},
department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Simulation gro{\ss}er Systeme},
abstract = {New experimental and analytical techniques like confocal laser scanning
microscopy (CSLM) or the use of RNA-targeted probes have provided insight into
the morphology, architecture, and function of biofilm cultures. The different
observations made there suggest that more attention has to be paid to a
detailed study of the microscale processes like flow and transport phenomena as
well as to the development of the bofilm's primary components, i.e. microbial
cells and extracellular polymeric substances (EPS). For that, numerical
simulations are a promising approach. However, due to the large variety of
different effects and influence factors, strong multiscale characteristics with
respect to both time and space, and due to the need for an explicit high
spatial resolution in order to capture the occurring changes of the underlying
geometry because of biomass growth, for example, 3D simulations have hardly
been tackled so far. Actually, most existing simulation tools for biofilm
systems are based on strongly simplified model assumptions that turned out to
be not valid in general.
In this work, we report on first steps towards microscale simulations of flow,
transport, reactive, and growth processes in 3D biofilm geometries obtained
from CLSM images of a small and defined monoculture biofilm setup. The basic
framework is the finite volume CFD solver Nast++, to which transport equations
(convection-diffusion in the fluid phase, diffusion-reaction in the biofilm)
and the cellular automaton CAsim for capturing biomass growth are coupled. Some
numerical results of realized simulations as well as strategies for an
increased numerical efficiency are presented.},
url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2003-07&engl=0}
}
