---
_id: '1237'
abstract:
- lang: eng
  text: 'Bitmap images of arbitrary dimension may be formally perceived as unions
    of m-dimensional boxes aligned with respect to a rectangular grid in ℝm. Cohomology
    and homology groups are well known topological invariants of such sets. Cohomological
    operations, such as the cup product, provide higher-order algebraic topological
    invariants, especially important for digital images of dimension higher than 3.
    If such an operation is determined at the level of simplicial chains [see e.g.
    González-Díaz, Real, Homology, Homotopy Appl, 2003, 83-93], then it is effectively
    computable. However, decomposing a cubical complex into a simplicial one deleteriously
    affects the efficiency of such an approach. In order to avoid this overhead, a
    direct cubical approach was applied in [Pilarczyk, Real, Adv. Comput. Math., 2015,
    253-275] for the cup product in cohomology, and implemented in the ChainCon software
    package [http://www.pawelpilarczyk.com/chaincon/]. We establish a formula for
    the Steenrod square operations [see Steenrod, Annals of Mathematics. Second Series,
    1947, 290-320] directly at the level of cubical chains, and we prove the correctness
    of this formula. An implementation of this formula is programmed in C++ within
    the ChainCon software framework. We provide a few examples and discuss the effectiveness
    of this approach. One specific application follows from the fact that Steenrod
    squares yield tests for the topological extension problem: Can a given map A →
    Sd to a sphere Sd be extended to a given super-complex X of A? In particular,
    the ROB-SAT problem, which is to decide for a given function f: X → ℝm and a value
    r &gt; 0 whether every g: X → ℝm with ∥g - f ∥∞ ≤ r has a root, reduces to the
    extension problem.'
acknowledgement: The research conducted by both authors has received funding from
  the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework
  Programme (FP7/2007-2013) under REA grant agreements no. 291734 (for M. K.) and
  no. 622033 (for P. P.).
alternative_title:
- LNCS
author:
- first_name: Marek
  full_name: Krcál, Marek
  id: 33E21118-F248-11E8-B48F-1D18A9856A87
  last_name: Krcál
- first_name: Pawel
  full_name: Pilarczyk, Pawel
  id: 3768D56A-F248-11E8-B48F-1D18A9856A87
  last_name: Pilarczyk
citation:
  ama: 'Krcál M, Pilarczyk P. Computation of cubical Steenrod squares. In: Vol 9667.
    Springer; 2016:140-151. doi:<a href="https://doi.org/10.1007/978-3-319-39441-1_13">10.1007/978-3-319-39441-1_13</a>'
  apa: 'Krcál, M., &#38; Pilarczyk, P. (2016). Computation of cubical Steenrod squares
    (Vol. 9667, pp. 140–151). Presented at the CTIC: Computational Topology in Image
    Context, Marseille, France: Springer. <a href="https://doi.org/10.1007/978-3-319-39441-1_13">https://doi.org/10.1007/978-3-319-39441-1_13</a>'
  chicago: Krcál, Marek, and Pawel Pilarczyk. “Computation of Cubical Steenrod Squares,”
    9667:140–51. Springer, 2016. <a href="https://doi.org/10.1007/978-3-319-39441-1_13">https://doi.org/10.1007/978-3-319-39441-1_13</a>.
  ieee: 'M. Krcál and P. Pilarczyk, “Computation of cubical Steenrod squares,” presented
    at the CTIC: Computational Topology in Image Context, Marseille, France, 2016,
    vol. 9667, pp. 140–151.'
  ista: 'Krcál M, Pilarczyk P. 2016. Computation of cubical Steenrod squares. CTIC:
    Computational Topology in Image Context, LNCS, vol. 9667, 140–151.'
  mla: Krcál, Marek, and Pawel Pilarczyk. <i>Computation of Cubical Steenrod Squares</i>.
    Vol. 9667, Springer, 2016, pp. 140–51, doi:<a href="https://doi.org/10.1007/978-3-319-39441-1_13">10.1007/978-3-319-39441-1_13</a>.
  short: M. Krcál, P. Pilarczyk, in:, Springer, 2016, pp. 140–151.
conference:
  end_date: 2016-06-17
  location: Marseille, France
  name: 'CTIC: Computational Topology in Image Context'
  start_date: 2016-06-15
date_created: 2018-12-11T11:50:52Z
date_published: 2016-06-02T00:00:00Z
date_updated: 2021-01-12T06:49:18Z
day: '02'
department:
- _id: UlWa
- _id: HeEd
doi: 10.1007/978-3-319-39441-1_13
ec_funded: 1
intvolume: '      9667'
language:
- iso: eng
month: '06'
oa_version: None
page: 140 - 151
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
- _id: 255F06BE-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '622033'
  name: Persistent Homology - Images, Data and Maps
publication_status: published
publisher: Springer
publist_id: '6096'
quality_controlled: '1'
scopus_import: 1
status: public
title: Computation of cubical Steenrod squares
type: conference
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 9667
year: '2016'
...
---
_id: '1252'
abstract:
- lang: eng
  text: We study the homomorphism induced in homology by a closed correspondence between
    topological spaces, using projections from the graph of the correspondence to
    its domain and codomain. We provide assumptions under which the homomorphism induced
    by an outer approximation of a continuous map coincides with the homomorphism
    induced in homology by the map. In contrast to more classical results we do not
    require that the projection to the domain have acyclic preimages. Moreover, we
    show that it is possible to retrieve correct homological information from a correspondence
    even if some data is missing or perturbed. Finally, we describe an application
    to combinatorial maps that are either outer approximations of continuous maps
    or reconstructions of such maps from a finite set of data points.
acknowledgement: "The authors gratefully acknowledge the support of the Lorenz Center
  which\r\nprovided an opportunity for us to discuss in depth the work of this paper.
  Research leading to these results has received funding from Fundo Europeu de Desenvolvimento
  Regional (FEDER) through COMPETE—Programa Operacional Factores de Competitividade
  (POFC) and from the Portuguese national funds through Funda¸c˜ao para a Ciˆencia
  e a Tecnologia (FCT) in the framework of the research\r\nproject FCOMP-01-0124-FEDER-010645
  (ref. FCT PTDC/MAT/098871/2008),\r\nas well as from the People Programme (Marie
  Curie Actions) of the European\r\nUnion’s Seventh Framework Programme (FP7/2007-2013)
  under REA grant agreement no. 622033 (supporting PP). The work of the first and
  third author has\r\nbeen partially supported by NSF grants NSF-DMS-0835621, 0915019,
  1125174,\r\n1248071, and contracts from AFOSR and DARPA. The work of the second
  author\r\nwas supported by Grant-in-Aid for Scientific Research (No. 25287029),
  Ministry of\r\nEducation, Science, Technology, Culture and Sports, Japan."
article_processing_charge: No
article_type: original
arxiv: 1
author:
- first_name: Shaun
  full_name: Harker, Shaun
  last_name: Harker
- first_name: Hiroshi
  full_name: Kokubu, Hiroshi
  last_name: Kokubu
- first_name: Konstantin
  full_name: Mischaikow, Konstantin
  last_name: Mischaikow
- first_name: Pawel
  full_name: Pilarczyk, Pawel
  id: 3768D56A-F248-11E8-B48F-1D18A9856A87
  last_name: Pilarczyk
citation:
  ama: Harker S, Kokubu H, Mischaikow K, Pilarczyk P. Inducing a map on homology from
    a correspondence. <i>Proceedings of the American Mathematical Society</i>. 2016;144(4):1787-1801.
    doi:<a href="https://doi.org/10.1090/proc/12812">10.1090/proc/12812</a>
  apa: Harker, S., Kokubu, H., Mischaikow, K., &#38; Pilarczyk, P. (2016). Inducing
    a map on homology from a correspondence. <i>Proceedings of the American Mathematical
    Society</i>. American Mathematical Society. <a href="https://doi.org/10.1090/proc/12812">https://doi.org/10.1090/proc/12812</a>
  chicago: Harker, Shaun, Hiroshi Kokubu, Konstantin Mischaikow, and Pawel Pilarczyk.
    “Inducing a Map on Homology from a Correspondence.” <i>Proceedings of the American
    Mathematical Society</i>. American Mathematical Society, 2016. <a href="https://doi.org/10.1090/proc/12812">https://doi.org/10.1090/proc/12812</a>.
  ieee: S. Harker, H. Kokubu, K. Mischaikow, and P. Pilarczyk, “Inducing a map on
    homology from a correspondence,” <i>Proceedings of the American Mathematical Society</i>,
    vol. 144, no. 4. American Mathematical Society, pp. 1787–1801, 2016.
  ista: Harker S, Kokubu H, Mischaikow K, Pilarczyk P. 2016. Inducing a map on homology
    from a correspondence. Proceedings of the American Mathematical Society. 144(4),
    1787–1801.
  mla: Harker, Shaun, et al. “Inducing a Map on Homology from a Correspondence.” <i>Proceedings
    of the American Mathematical Society</i>, vol. 144, no. 4, American Mathematical
    Society, 2016, pp. 1787–801, doi:<a href="https://doi.org/10.1090/proc/12812">10.1090/proc/12812</a>.
  short: S. Harker, H. Kokubu, K. Mischaikow, P. Pilarczyk, Proceedings of the American
    Mathematical Society 144 (2016) 1787–1801.
date_created: 2018-12-11T11:50:57Z
date_published: 2016-04-01T00:00:00Z
date_updated: 2022-05-24T09:35:58Z
day: '01'
department:
- _id: HeEd
doi: 10.1090/proc/12812
ec_funded: 1
external_id:
  arxiv:
  - '1411.7563'
intvolume: '       144'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1411.7563
month: '04'
oa: 1
oa_version: Preprint
page: 1787 - 1801
project:
- _id: 255F06BE-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '622033'
  name: Persistent Homology - Images, Data and Maps
publication: Proceedings of the American Mathematical Society
publication_identifier:
  issn:
  - 1088-6826
publication_status: published
publisher: American Mathematical Society
publist_id: '6075'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Inducing a map on homology from a correspondence
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 144
year: '2016'
...
---
_id: '1254'
abstract:
- lang: eng
  text: We use rigorous numerical techniques to compute a lower bound for the exponent
    of expansivity outside a neighborhood of the critical point for thousands of intervals
    of parameter values in the quadratic family. We first compute a radius of the
    critical neighborhood outside which the map is uniformly expanding. This radius
    is taken as small as possible, yet large enough for our numerical procedure to
    succeed in proving that the expansivity exponent outside this neighborhood is
    positive. Then, for each of the intervals, we compute a lower bound for this expansivity
    exponent, valid for all the parameters in that interval. We illustrate and study
    the distribution of the radii and the expansivity exponents. The results of our
    computations are mathematically rigorous. The source code of the software and
    the results of the computations are made publicly available at http://www.pawelpilarczyk.com/quadratic/.
acknowledgement: "AG and PP were partially supported by Abdus Salam International
  Centre for Theoretical Physics (ICTP). Additionally, AG was supported by BREUDS,
  and research conducted by PP has received funding from Fundo Europeu de Desenvolvimento
  Regional (FEDER) through COMPETE—Programa Operacional Factores de Competitividade
  (POFC) and from the Portuguese national funds through Fundação para a Ciência e
  a Tecnologia (FCT) in the framework of the research project FCOMP-01-0124-FEDER-010645
  (ref. FCT PTDC/MAT/098871/2008); and from the People Programme (Marie Curie Actions)
  of the European Union’s Seventh Framework Programme (FP7/2007-2013) under REA grant
  agreement no. 622033. The  authors  gratefully  acknowledge  the  Department  of\r\nMathematics
  \ of  Kyoto  University  for  providing  access\r\nto  their  server  for  conducting
  \ computations  for  this\r\nproject."
author:
- first_name: Ali
  full_name: Golmakani, Ali
  last_name: Golmakani
- first_name: Stefano
  full_name: Luzzatto, Stefano
  last_name: Luzzatto
- first_name: Pawel
  full_name: Pilarczyk, Pawel
  id: 3768D56A-F248-11E8-B48F-1D18A9856A87
  last_name: Pilarczyk
citation:
  ama: Golmakani A, Luzzatto S, Pilarczyk P. Uniform expansivity outside a critical
    neighborhood in the quadratic family. <i>Experimental Mathematics</i>. 2016;25(2):116-124.
    doi:<a href="https://doi.org/10.1080/10586458.2015.1048011">10.1080/10586458.2015.1048011</a>
  apa: Golmakani, A., Luzzatto, S., &#38; Pilarczyk, P. (2016). Uniform expansivity
    outside a critical neighborhood in the quadratic family. <i>Experimental Mathematics</i>.
    Taylor and Francis. <a href="https://doi.org/10.1080/10586458.2015.1048011">https://doi.org/10.1080/10586458.2015.1048011</a>
  chicago: Golmakani, Ali, Stefano Luzzatto, and Pawel Pilarczyk. “Uniform Expansivity
    Outside a Critical Neighborhood in the Quadratic Family.” <i>Experimental Mathematics</i>.
    Taylor and Francis, 2016. <a href="https://doi.org/10.1080/10586458.2015.1048011">https://doi.org/10.1080/10586458.2015.1048011</a>.
  ieee: A. Golmakani, S. Luzzatto, and P. Pilarczyk, “Uniform expansivity outside
    a critical neighborhood in the quadratic family,” <i>Experimental Mathematics</i>,
    vol. 25, no. 2. Taylor and Francis, pp. 116–124, 2016.
  ista: Golmakani A, Luzzatto S, Pilarczyk P. 2016. Uniform expansivity outside a
    critical neighborhood in the quadratic family. Experimental Mathematics. 25(2),
    116–124.
  mla: Golmakani, Ali, et al. “Uniform Expansivity Outside a Critical Neighborhood
    in the Quadratic Family.” <i>Experimental Mathematics</i>, vol. 25, no. 2, Taylor
    and Francis, 2016, pp. 116–24, doi:<a href="https://doi.org/10.1080/10586458.2015.1048011">10.1080/10586458.2015.1048011</a>.
  short: A. Golmakani, S. Luzzatto, P. Pilarczyk, Experimental Mathematics 25 (2016)
    116–124.
date_created: 2018-12-11T11:50:58Z
date_published: 2016-04-02T00:00:00Z
date_updated: 2021-01-12T06:49:25Z
day: '02'
department:
- _id: HeEd
doi: 10.1080/10586458.2015.1048011
ec_funded: 1
intvolume: '        25'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1504.00116
month: '04'
oa: 1
oa_version: Preprint
page: 116 - 124
project:
- _id: 255F06BE-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '622033'
  name: Persistent Homology - Images, Data and Maps
publication: Experimental Mathematics
publication_status: published
publisher: Taylor and Francis
publist_id: '6071'
quality_controlled: '1'
scopus_import: 1
status: public
title: Uniform expansivity outside a critical neighborhood in the quadratic family
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 25
year: '2016'
...
---
_id: '1272'
abstract:
- lang: eng
  text: We study different means to extend offsetting based on skeletal structures
    beyond the well-known constant-radius and mitered offsets supported by Voronoi
    diagrams and straight skeletons, for which the orthogonal distance of offset elements
    to their respective input elements is constant and uniform over all input elements.
    Our main contribution is a new geometric structure, called variable-radius Voronoi
    diagram, which supports the computation of variable-radius offsets, i.e., offsets
    whose distance to the input is allowed to vary along the input. We discuss properties
    of this structure and sketch a prototype implementation that supports the computation
    of variable-radius offsets based on this new variant of Voronoi diagrams.
acknowledgement: 'This work was supported by Austrian Science Fund (FWF): P25816-N15.'
author:
- first_name: Martin
  full_name: Held, Martin
  last_name: Held
- first_name: Stefan
  full_name: Huber, Stefan
  id: 4700A070-F248-11E8-B48F-1D18A9856A87
  last_name: Huber
  orcid: 0000-0002-8871-5814
- first_name: Peter
  full_name: Palfrader, Peter
  last_name: Palfrader
citation:
  ama: Held M, Huber S, Palfrader P. Generalized offsetting of planar structures using
    skeletons. <i>Computer-Aided Design and Applications</i>. 2016;13(5):712-721.
    doi:<a href="https://doi.org/10.1080/16864360.2016.1150718">10.1080/16864360.2016.1150718</a>
  apa: Held, M., Huber, S., &#38; Palfrader, P. (2016). Generalized offsetting of
    planar structures using skeletons. <i>Computer-Aided Design and Applications</i>.
    Taylor and Francis. <a href="https://doi.org/10.1080/16864360.2016.1150718">https://doi.org/10.1080/16864360.2016.1150718</a>
  chicago: Held, Martin, Stefan Huber, and Peter Palfrader. “Generalized Offsetting
    of Planar Structures Using Skeletons.” <i>Computer-Aided Design and Applications</i>.
    Taylor and Francis, 2016. <a href="https://doi.org/10.1080/16864360.2016.1150718">https://doi.org/10.1080/16864360.2016.1150718</a>.
  ieee: M. Held, S. Huber, and P. Palfrader, “Generalized offsetting of planar structures
    using skeletons,” <i>Computer-Aided Design and Applications</i>, vol. 13, no.
    5. Taylor and Francis, pp. 712–721, 2016.
  ista: Held M, Huber S, Palfrader P. 2016. Generalized offsetting of planar structures
    using skeletons. Computer-Aided Design and Applications. 13(5), 712–721.
  mla: Held, Martin, et al. “Generalized Offsetting of Planar Structures Using Skeletons.”
    <i>Computer-Aided Design and Applications</i>, vol. 13, no. 5, Taylor and Francis,
    2016, pp. 712–21, doi:<a href="https://doi.org/10.1080/16864360.2016.1150718">10.1080/16864360.2016.1150718</a>.
  short: M. Held, S. Huber, P. Palfrader, Computer-Aided Design and Applications 13
    (2016) 712–721.
date_created: 2018-12-11T11:51:04Z
date_published: 2016-09-02T00:00:00Z
date_updated: 2021-01-12T06:49:32Z
day: '02'
ddc:
- '004'
- '516'
department:
- _id: HeEd
doi: 10.1080/16864360.2016.1150718
file:
- access_level: open_access
  checksum: c746f3a48edb62b588d92ea5d0fd2c0e
  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:16:20Z
  date_updated: 2020-07-14T12:44:42Z
  file_id: '5206'
  file_name: IST-2016-694-v1+1_Generalized_offsetting_of_planar_structures_using_skeletons.pdf
  file_size: 1678369
  relation: main_file
file_date_updated: 2020-07-14T12:44:42Z
has_accepted_license: '1'
intvolume: '        13'
issue: '5'
language:
- iso: eng
month: '09'
oa: 1
oa_version: Published Version
page: 712 - 721
publication: Computer-Aided Design and Applications
publication_status: published
publisher: Taylor and Francis
publist_id: '6048'
pubrep_id: '694'
quality_controlled: '1'
scopus_import: 1
status: public
title: Generalized offsetting of planar structures using skeletons
tmp:
  image: /images/cc_by_nc_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
    (CC BY-NC-ND 4.0)
  short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 13
year: '2016'
...
---
_id: '1289'
abstract:
- lang: eng
  text: 'Aiming at the automatic diagnosis of tumors using narrow band imaging (NBI)
    magnifying endoscopic (ME) images of the stomach, we combine methods from image
    processing, topology, geometry, and machine learning to classify patterns into
    three classes: oval, tubular and irregular. Training the algorithm on a small
    number of images of each type, we achieve a high rate of correct classifications.
    The analysis of the learning algorithm reveals that a handful of geometric and
    topological features are responsible for the overwhelming majority of decisions.'
article_processing_charge: No
author:
- first_name: Olga
  full_name: Dunaeva, Olga
  last_name: Dunaeva
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Anton
  full_name: Lukyanov, Anton
  last_name: Lukyanov
- first_name: Michael
  full_name: Machin, Michael
  last_name: Machin
- first_name: Daria
  full_name: Malkova, Daria
  last_name: Malkova
- first_name: Roman
  full_name: Kuvaev, Roman
  last_name: Kuvaev
- first_name: Sergey
  full_name: Kashin, Sergey
  last_name: Kashin
citation:
  ama: Dunaeva O, Edelsbrunner H, Lukyanov A, et al. The classification of endoscopy
    images with persistent homology. <i>Pattern Recognition Letters</i>. 2016;83(1):13-22.
    doi:<a href="https://doi.org/10.1016/j.patrec.2015.12.012">10.1016/j.patrec.2015.12.012</a>
  apa: Dunaeva, O., Edelsbrunner, H., Lukyanov, A., Machin, M., Malkova, D., Kuvaev,
    R., &#38; Kashin, S. (2016). The classification of endoscopy images with persistent
    homology. <i>Pattern Recognition Letters</i>. Elsevier. <a href="https://doi.org/10.1016/j.patrec.2015.12.012">https://doi.org/10.1016/j.patrec.2015.12.012</a>
  chicago: Dunaeva, Olga, Herbert Edelsbrunner, Anton Lukyanov, Michael Machin, Daria
    Malkova, Roman Kuvaev, and Sergey Kashin. “The Classification of Endoscopy Images
    with Persistent Homology.” <i>Pattern Recognition Letters</i>. Elsevier, 2016.
    <a href="https://doi.org/10.1016/j.patrec.2015.12.012">https://doi.org/10.1016/j.patrec.2015.12.012</a>.
  ieee: O. Dunaeva <i>et al.</i>, “The classification of endoscopy images with persistent
    homology,” <i>Pattern Recognition Letters</i>, vol. 83, no. 1. Elsevier, pp. 13–22,
    2016.
  ista: Dunaeva O, Edelsbrunner H, Lukyanov A, Machin M, Malkova D, Kuvaev R, Kashin
    S. 2016. The classification of endoscopy images with persistent homology. Pattern
    Recognition Letters. 83(1), 13–22.
  mla: Dunaeva, Olga, et al. “The Classification of Endoscopy Images with Persistent
    Homology.” <i>Pattern Recognition Letters</i>, vol. 83, no. 1, Elsevier, 2016,
    pp. 13–22, doi:<a href="https://doi.org/10.1016/j.patrec.2015.12.012">10.1016/j.patrec.2015.12.012</a>.
  short: O. Dunaeva, H. Edelsbrunner, A. Lukyanov, M. Machin, D. Malkova, R. Kuvaev,
    S. Kashin, Pattern Recognition Letters 83 (2016) 13–22.
date_created: 2018-12-11T11:51:10Z
date_published: 2016-11-01T00:00:00Z
date_updated: 2023-02-23T10:04:40Z
day: '01'
ddc:
- '004'
- '514'
department:
- _id: HeEd
doi: 10.1016/j.patrec.2015.12.012
file:
- access_level: open_access
  checksum: 33458bbb8c32a339e1adeca6d5a1112d
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  date_created: 2019-04-17T07:55:51Z
  date_updated: 2020-07-14T12:44:42Z
  file_id: '6334'
  file_name: 2016-Edelsbrunner_The_classification.pdf
  file_size: 1921113
  relation: main_file
file_date_updated: 2020-07-14T12:44:42Z
has_accepted_license: '1'
intvolume: '        83'
issue: '1'
language:
- iso: eng
month: '11'
oa: 1
oa_version: Submitted Version
page: 13 - 22
publication: Pattern Recognition Letters
publication_status: published
publisher: Elsevier
publist_id: '6027'
pubrep_id: '975'
quality_controlled: '1'
related_material:
  record:
  - id: '1568'
    relation: earlier_version
    status: public
scopus_import: 1
status: public
title: The classification of endoscopy images with persistent homology
tmp:
  image: /images/cc_by_nc_nd.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
    (CC BY-NC-ND 4.0)
  short: CC BY-NC-ND (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 83
year: '2016'
...
---
_id: '1292'
abstract:
- lang: eng
  text: We give explicit formulas and algorithms for the computation of the Thurston–Bennequin
    invariant of a nullhomologous Legendrian knot on a page of a contact open book
    and on Heegaard surfaces in convex position. Furthermore, we extend the results
    to rationally nullhomologous knots in arbitrary 3-manifolds.
acknowledgement: "The authors are veryg rateful to Hansj ̈org Geiges \r\nfor fruitful
  discussions and advice and Christian Evers for helpful remarks on a draft version."
author:
- first_name: Sebastian
  full_name: Durst, Sebastian
  last_name: Durst
- first_name: Marc
  full_name: Kegel, Marc
  last_name: Kegel
- first_name: Mirko D
  full_name: Klukas, Mirko D
  id: 34927512-F248-11E8-B48F-1D18A9856A87
  last_name: Klukas
citation:
  ama: Durst S, Kegel M, Klukas MD. Computing the Thurston–Bennequin invariant in
    open books. <i>Acta Mathematica Hungarica</i>. 2016;150(2):441-455. doi:<a href="https://doi.org/10.1007/s10474-016-0648-4">10.1007/s10474-016-0648-4</a>
  apa: Durst, S., Kegel, M., &#38; Klukas, M. D. (2016). Computing the Thurston–Bennequin
    invariant in open books. <i>Acta Mathematica Hungarica</i>. Springer. <a href="https://doi.org/10.1007/s10474-016-0648-4">https://doi.org/10.1007/s10474-016-0648-4</a>
  chicago: Durst, Sebastian, Marc Kegel, and Mirko D Klukas. “Computing the Thurston–Bennequin
    Invariant in Open Books.” <i>Acta Mathematica Hungarica</i>. Springer, 2016. <a
    href="https://doi.org/10.1007/s10474-016-0648-4">https://doi.org/10.1007/s10474-016-0648-4</a>.
  ieee: S. Durst, M. Kegel, and M. D. Klukas, “Computing the Thurston–Bennequin invariant
    in open books,” <i>Acta Mathematica Hungarica</i>, vol. 150, no. 2. Springer,
    pp. 441–455, 2016.
  ista: Durst S, Kegel M, Klukas MD. 2016. Computing the Thurston–Bennequin invariant
    in open books. Acta Mathematica Hungarica. 150(2), 441–455.
  mla: Durst, Sebastian, et al. “Computing the Thurston–Bennequin Invariant in Open
    Books.” <i>Acta Mathematica Hungarica</i>, vol. 150, no. 2, Springer, 2016, pp.
    441–55, doi:<a href="https://doi.org/10.1007/s10474-016-0648-4">10.1007/s10474-016-0648-4</a>.
  short: S. Durst, M. Kegel, M.D. Klukas, Acta Mathematica Hungarica 150 (2016) 441–455.
date_created: 2018-12-11T11:51:11Z
date_published: 2016-12-01T00:00:00Z
date_updated: 2021-01-12T06:49:40Z
day: '01'
department:
- _id: HeEd
doi: 10.1007/s10474-016-0648-4
intvolume: '       150'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1605.00794
month: '12'
oa: 1
oa_version: Preprint
page: 441 - 455
publication: Acta Mathematica Hungarica
publication_status: published
publisher: Springer
publist_id: '6023'
quality_controlled: '1'
scopus_import: 1
status: public
title: Computing the Thurston–Bennequin invariant in open books
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 150
year: '2016'
...
---
_id: '1295'
abstract:
- lang: eng
  text: Voronoi diagrams and Delaunay triangulations have been extensively used to
    represent and compute geometric features of point configurations. We introduce
    a generalization to poset diagrams and poset complexes, which contain order-k
    and degree-k Voronoi diagrams and their duals as special cases. Extending a result
    of Aurenhammer from 1990, we show how to construct poset diagrams as weighted
    Voronoi diagrams of average balls.
acknowledgement: This work is partially supported by the Toposys project FP7-ICT-318493-STREP,
  and by ESF under the ACAT Research Network Programme.
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Mabel
  full_name: Iglesias Ham, Mabel
  id: 41B58C0C-F248-11E8-B48F-1D18A9856A87
  last_name: Iglesias Ham
citation:
  ama: 'Edelsbrunner H, Iglesias Ham M. Multiple covers with balls II: Weighted averages.
    <i>Electronic Notes in Discrete Mathematics</i>. 2016;54:169-174. doi:<a href="https://doi.org/10.1016/j.endm.2016.09.030">10.1016/j.endm.2016.09.030</a>'
  apa: 'Edelsbrunner, H., &#38; Iglesias Ham, M. (2016). Multiple covers with balls
    II: Weighted averages. <i>Electronic Notes in Discrete Mathematics</i>. Elsevier.
    <a href="https://doi.org/10.1016/j.endm.2016.09.030">https://doi.org/10.1016/j.endm.2016.09.030</a>'
  chicago: 'Edelsbrunner, Herbert, and Mabel Iglesias Ham. “Multiple Covers with Balls
    II: Weighted Averages.” <i>Electronic Notes in Discrete Mathematics</i>. Elsevier,
    2016. <a href="https://doi.org/10.1016/j.endm.2016.09.030">https://doi.org/10.1016/j.endm.2016.09.030</a>.'
  ieee: 'H. Edelsbrunner and M. Iglesias Ham, “Multiple covers with balls II: Weighted
    averages,” <i>Electronic Notes in Discrete Mathematics</i>, vol. 54. Elsevier,
    pp. 169–174, 2016.'
  ista: 'Edelsbrunner H, Iglesias Ham M. 2016. Multiple covers with balls II: Weighted
    averages. Electronic Notes in Discrete Mathematics. 54, 169–174.'
  mla: 'Edelsbrunner, Herbert, and Mabel Iglesias Ham. “Multiple Covers with Balls
    II: Weighted Averages.” <i>Electronic Notes in Discrete Mathematics</i>, vol.
    54, Elsevier, 2016, pp. 169–74, doi:<a href="https://doi.org/10.1016/j.endm.2016.09.030">10.1016/j.endm.2016.09.030</a>.'
  short: H. Edelsbrunner, M. Iglesias Ham, Electronic Notes in Discrete Mathematics
    54 (2016) 169–174.
date_created: 2018-12-11T11:51:12Z
date_published: 2016-10-01T00:00:00Z
date_updated: 2021-01-12T06:49:41Z
day: '01'
department:
- _id: HeEd
doi: 10.1016/j.endm.2016.09.030
ec_funded: 1
intvolume: '        54'
language:
- iso: eng
month: '10'
oa_version: None
page: 169 - 174
project:
- _id: 255D761E-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '318493'
  name: Topological Complex Systems
publication: Electronic Notes in Discrete Mathematics
publication_status: published
publisher: Elsevier
publist_id: '5976'
quality_controlled: '1'
scopus_import: 1
status: public
title: 'Multiple covers with balls II: Weighted averages'
type: journal_article
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 54
year: '2016'
...
---
_id: '1682'
abstract:
- lang: eng
  text: 'We study the problem of robust satisfiability of systems of nonlinear equations,
    namely, whether for a given continuous function f:K→ ℝn on a finite simplicial
    complex K and α &gt; 0, it holds that each function g: K → ℝn such that ||g -
    f || ∞ &lt; α, has a root in K. Via a reduction to the extension problem of maps
    into a sphere, we particularly show that this problem is decidable in polynomial
    time for every fixed n, assuming dimK ≤ 2n - 3. This is a substantial extension
    of previous computational applications of topological degree and related concepts
    in numerical and interval analysis. Via a reverse reduction, we prove that the
    problem is undecidable when dim K &gt; 2n - 2, where the threshold comes from
    the stable range in homotopy theory. For the lucidity of our exposition, we focus
    on the setting when f is simplexwise linear. Such functions can approximate general
    continuous functions, and thus we get approximation schemes and undecidability
    of the robust satisfiability in other possible settings.'
article_number: '26'
author:
- first_name: Peter
  full_name: Franek, Peter
  last_name: Franek
- first_name: Marek
  full_name: Krcál, Marek
  id: 33E21118-F248-11E8-B48F-1D18A9856A87
  last_name: Krcál
citation:
  ama: Franek P, Krcál M. Robust satisfiability of systems of equations. <i>Journal
    of the ACM</i>. 2015;62(4). doi:<a href="https://doi.org/10.1145/2751524">10.1145/2751524</a>
  apa: Franek, P., &#38; Krcál, M. (2015). Robust satisfiability of systems of equations.
    <i>Journal of the ACM</i>. ACM. <a href="https://doi.org/10.1145/2751524">https://doi.org/10.1145/2751524</a>
  chicago: Franek, Peter, and Marek Krcál. “Robust Satisfiability of Systems of Equations.”
    <i>Journal of the ACM</i>. ACM, 2015. <a href="https://doi.org/10.1145/2751524">https://doi.org/10.1145/2751524</a>.
  ieee: P. Franek and M. Krcál, “Robust satisfiability of systems of equations,” <i>Journal
    of the ACM</i>, vol. 62, no. 4. ACM, 2015.
  ista: Franek P, Krcál M. 2015. Robust satisfiability of systems of equations. Journal
    of the ACM. 62(4), 26.
  mla: Franek, Peter, and Marek Krcál. “Robust Satisfiability of Systems of Equations.”
    <i>Journal of the ACM</i>, vol. 62, no. 4, 26, ACM, 2015, doi:<a href="https://doi.org/10.1145/2751524">10.1145/2751524</a>.
  short: P. Franek, M. Krcál, Journal of the ACM 62 (2015).
date_created: 2018-12-11T11:53:27Z
date_published: 2015-08-01T00:00:00Z
date_updated: 2021-01-12T06:52:30Z
day: '01'
department:
- _id: UlWa
- _id: HeEd
doi: 10.1145/2751524
intvolume: '        62'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://arxiv.org/abs/1402.0858
month: '08'
oa: 1
oa_version: Preprint
publication: Journal of the ACM
publication_status: published
publisher: ACM
publist_id: '5466'
quality_controlled: '1'
scopus_import: 1
status: public
title: Robust satisfiability of systems of equations
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 62
year: '2015'
...
---
_id: '1710'
abstract:
- lang: eng
  text: 'We consider the hollow on the half-plane {(x, y) : y ≤ 0} ⊂ ℝ2 defined by
    a function u : (-1, 1) → ℝ, u(x) &lt; 0, and a vertical flow of point particles
    incident on the hollow. It is assumed that u satisfies the so-called single impact
    condition (SIC): each incident particle is elastically reflected by graph(u) and
    goes away without hitting the graph of u anymore. We solve the problem: find the
    function u minimizing the force of resistance created by the flow. We show that
    the graph of the minimizer is formed by two arcs of parabolas symmetric to each
    other with respect to the y-axis. Assuming that the resistance of u ≡ 0 equals
    1, we show that the minimal resistance equals π/2 - 2arctan(1/2) ≈ 0.6435. This
    result completes the previously obtained result [SIAM J. Math. Anal., 46 (2014),
    pp. 2730-2742] stating in particular that the minimal resistance of a hollow in
    higher dimensions equals 0.5. We additionally consider a similar problem of minimal
    resistance, where the hollow in the half-space {(x1,...,xd,y) : y ≤ 0} ⊂ ℝd+1
    is defined by a radial function U satisfying the SIC, U(x) = u(|x|), with x =
    (x1,...,xd), u(ξ) &lt; 0 for 0 ≤ ξ &lt; 1, and u(ξ) = 0 for ξ ≥ 1, and the flow
    is parallel to the y-axis. The minimal resistance is greater than 0.5 (and coincides
    with 0.6435 when d = 1) and converges to 0.5 as d → ∞.'
author:
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Alexander
  full_name: Plakhov, Alexander
  last_name: Plakhov
citation:
  ama: Akopyan A, Plakhov A. Minimal resistance of curves under the single impact
    assumption. <i>Society for Industrial and Applied Mathematics</i>. 2015;47(4):2754-2769.
    doi:<a href="https://doi.org/10.1137/140993843">10.1137/140993843</a>
  apa: Akopyan, A., &#38; Plakhov, A. (2015). Minimal resistance of curves under the
    single impact assumption. <i>Society for Industrial and Applied Mathematics</i>.
    SIAM. <a href="https://doi.org/10.1137/140993843">https://doi.org/10.1137/140993843</a>
  chicago: Akopyan, Arseniy, and Alexander Plakhov. “Minimal Resistance of Curves
    under the Single Impact Assumption.” <i>Society for Industrial and Applied Mathematics</i>.
    SIAM, 2015. <a href="https://doi.org/10.1137/140993843">https://doi.org/10.1137/140993843</a>.
  ieee: A. Akopyan and A. Plakhov, “Minimal resistance of curves under the single
    impact assumption,” <i>Society for Industrial and Applied Mathematics</i>, vol.
    47, no. 4. SIAM, pp. 2754–2769, 2015.
  ista: Akopyan A, Plakhov A. 2015. Minimal resistance of curves under the single
    impact assumption. Society for Industrial and Applied Mathematics. 47(4), 2754–2769.
  mla: Akopyan, Arseniy, and Alexander Plakhov. “Minimal Resistance of Curves under
    the Single Impact Assumption.” <i>Society for Industrial and Applied Mathematics</i>,
    vol. 47, no. 4, SIAM, 2015, pp. 2754–69, doi:<a href="https://doi.org/10.1137/140993843">10.1137/140993843</a>.
  short: A. Akopyan, A. Plakhov, Society for Industrial and Applied Mathematics 47
    (2015) 2754–2769.
date_created: 2018-12-11T11:53:36Z
date_published: 2015-07-14T00:00:00Z
date_updated: 2021-01-12T06:52:41Z
day: '14'
department:
- _id: HeEd
doi: 10.1137/140993843
ec_funded: 1
intvolume: '        47'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://arxiv.org/abs/1410.3736
month: '07'
oa: 1
oa_version: Preprint
page: 2754 - 2769
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
publication: Society for Industrial and Applied Mathematics
publication_status: published
publisher: SIAM
publist_id: '5423'
quality_controlled: '1'
scopus_import: 1
status: public
title: Minimal resistance of curves under the single impact assumption
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 47
year: '2015'
...
---
_id: '1792'
abstract:
- lang: eng
  text: Motivated by recent ideas of Harman (Unif. Distrib. Theory, 2010) we develop
    a new concept of variation of multivariate functions on a compact Hausdorff space
    with respect to a collection D of subsets. We prove a general version of the Koksma-Hlawka
    theorem that holds for this notion of variation and discrepancy with respect to
    D. As special cases, we obtain Koksma-Hlawka inequalities for classical notions,
    such as extreme or isotropic discrepancy. For extreme discrepancy, our result
    coincides with the usual Koksma-Hlawka theorem. We show that the space of functions
    of bounded D-variation contains important discontinuous functions and is closed
    under natural algebraic operations. Finally, we illustrate the results on concrete
    integration problems from integral geometry and stereology.
acknowledgement: F.P. is supported by the Graduate School of IST Austria, A.M.S is
  supported by the Centre for Stochastic Geometry and Advanced Bioimaging funded by
  a grant from the Villum Foundation.
author:
- first_name: Florian
  full_name: Pausinger, Florian
  id: 2A77D7A2-F248-11E8-B48F-1D18A9856A87
  last_name: Pausinger
  orcid: 0000-0002-8379-3768
- first_name: Anne
  full_name: Svane, Anne
  last_name: Svane
citation:
  ama: Pausinger F, Svane A. A Koksma-Hlawka inequality for general discrepancy systems.
    <i>Journal of Complexity</i>. 2015;31(6):773-797. doi:<a href="https://doi.org/10.1016/j.jco.2015.06.002">10.1016/j.jco.2015.06.002</a>
  apa: Pausinger, F., &#38; Svane, A. (2015). A Koksma-Hlawka inequality for general
    discrepancy systems. <i>Journal of Complexity</i>. Academic Press. <a href="https://doi.org/10.1016/j.jco.2015.06.002">https://doi.org/10.1016/j.jco.2015.06.002</a>
  chicago: Pausinger, Florian, and Anne Svane. “A Koksma-Hlawka Inequality for General
    Discrepancy Systems.” <i>Journal of Complexity</i>. Academic Press, 2015. <a href="https://doi.org/10.1016/j.jco.2015.06.002">https://doi.org/10.1016/j.jco.2015.06.002</a>.
  ieee: F. Pausinger and A. Svane, “A Koksma-Hlawka inequality for general discrepancy
    systems,” <i>Journal of Complexity</i>, vol. 31, no. 6. Academic Press, pp. 773–797,
    2015.
  ista: Pausinger F, Svane A. 2015. A Koksma-Hlawka inequality for general discrepancy
    systems. Journal of Complexity. 31(6), 773–797.
  mla: Pausinger, Florian, and Anne Svane. “A Koksma-Hlawka Inequality for General
    Discrepancy Systems.” <i>Journal of Complexity</i>, vol. 31, no. 6, Academic Press,
    2015, pp. 773–97, doi:<a href="https://doi.org/10.1016/j.jco.2015.06.002">10.1016/j.jco.2015.06.002</a>.
  short: F. Pausinger, A. Svane, Journal of Complexity 31 (2015) 773–797.
date_created: 2018-12-11T11:54:02Z
date_published: 2015-12-01T00:00:00Z
date_updated: 2023-09-07T11:41:25Z
day: '01'
department:
- _id: HeEd
doi: 10.1016/j.jco.2015.06.002
intvolume: '        31'
issue: '6'
language:
- iso: eng
month: '12'
oa_version: None
page: 773 - 797
publication: Journal of Complexity
publication_status: published
publisher: Academic Press
publist_id: '5320'
quality_controlled: '1'
related_material:
  record:
  - id: '1399'
    relation: dissertation_contains
    status: public
scopus_import: 1
status: public
title: A Koksma-Hlawka inequality for general discrepancy systems
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 31
year: '2015'
...
---
_id: '1793'
abstract:
- lang: eng
  text: We present a software platform for reconstructing and analyzing the growth
    of a plant root system from a time-series of 3D voxelized shapes. It aligns the
    shapes with each other, constructs a geometric graph representation together with
    the function that records the time of growth, and organizes the branches into
    a hierarchy that reflects the order of creation. The software includes the automatic
    computation of structural and dynamic traits for each root in the system enabling
    the quantification of growth on fine-scale. These are important advances in plant
    phenotyping with applications to the study of genetic and environmental influences
    on growth.
article_number: e0127657
author:
- first_name: Olga
  full_name: Symonova, Olga
  id: 3C0C7BC6-F248-11E8-B48F-1D18A9856A87
  last_name: Symonova
- first_name: Christopher
  full_name: Topp, Christopher
  last_name: Topp
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
citation:
  ama: 'Symonova O, Topp C, Edelsbrunner H. DynamicRoots: A software platform for
    the reconstruction and analysis of growing plant roots. <i>PLoS One</i>. 2015;10(6).
    doi:<a href="https://doi.org/10.1371/journal.pone.0127657">10.1371/journal.pone.0127657</a>'
  apa: 'Symonova, O., Topp, C., &#38; Edelsbrunner, H. (2015). DynamicRoots: A software
    platform for the reconstruction and analysis of growing plant roots. <i>PLoS One</i>.
    Public Library of Science. <a href="https://doi.org/10.1371/journal.pone.0127657">https://doi.org/10.1371/journal.pone.0127657</a>'
  chicago: 'Symonova, Olga, Christopher Topp, and Herbert Edelsbrunner. “DynamicRoots:
    A Software Platform for the Reconstruction and Analysis of Growing Plant Roots.”
    <i>PLoS One</i>. Public Library of Science, 2015. <a href="https://doi.org/10.1371/journal.pone.0127657">https://doi.org/10.1371/journal.pone.0127657</a>.'
  ieee: 'O. Symonova, C. Topp, and H. Edelsbrunner, “DynamicRoots: A software platform
    for the reconstruction and analysis of growing plant roots,” <i>PLoS One</i>,
    vol. 10, no. 6. Public Library of Science, 2015.'
  ista: 'Symonova O, Topp C, Edelsbrunner H. 2015. DynamicRoots: A software platform
    for the reconstruction and analysis of growing plant roots. PLoS One. 10(6), e0127657.'
  mla: 'Symonova, Olga, et al. “DynamicRoots: A Software Platform for the Reconstruction
    and Analysis of Growing Plant Roots.” <i>PLoS One</i>, vol. 10, no. 6, e0127657,
    Public Library of Science, 2015, doi:<a href="https://doi.org/10.1371/journal.pone.0127657">10.1371/journal.pone.0127657</a>.'
  short: O. Symonova, C. Topp, H. Edelsbrunner, PLoS One 10 (2015).
date_created: 2018-12-11T11:54:02Z
date_published: 2015-06-01T00:00:00Z
date_updated: 2023-02-23T14:06:33Z
day: '01'
ddc:
- '000'
department:
- _id: MaJö
- _id: HeEd
doi: 10.1371/journal.pone.0127657
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  checksum: d20f26461ca575276ad3ed9ce4bfc787
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  date_updated: 2020-07-14T12:45:16Z
  file_id: '5150'
  file_name: IST-2016-454-v1+1_journal.pone.0127657.pdf
  file_size: 1850825
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file_date_updated: 2020-07-14T12:45:16Z
has_accepted_license: '1'
intvolume: '        10'
issue: '6'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
publication: PLoS One
publication_status: published
publisher: Public Library of Science
publist_id: '5318'
pubrep_id: '454'
quality_controlled: '1'
related_material:
  record:
  - id: '9737'
    relation: research_data
    status: public
scopus_import: 1
status: public
title: 'DynamicRoots: A software platform for the reconstruction and analysis of growing
  plant roots'
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 10
year: '2015'
...
---
_id: '1805'
abstract:
- lang: eng
  text: 'We consider the problem of deciding whether the persistent homology group
    of a simplicial pair (K,L) can be realized as the homology H∗(X) of some complex
    X with L ⊂ X ⊂ K. We show that this problem is NP-complete even if K is embedded
    in double-struck R3. As a consequence, we show that it is NP-hard to simplify
    level and sublevel sets of scalar functions on double-struck S3 within a given
    tolerance constraint. This problem has relevance to the visualization of medical
    images by isosurfaces. We also show an implication to the theory of well groups
    of scalar functions: not every well group can be realized by some level set, and
    deciding whether a well group can be realized is NP-hard.'
author:
- first_name: Dominique
  full_name: Attali, Dominique
  last_name: Attali
- first_name: Ulrich
  full_name: Bauer, Ulrich
  id: 2ADD483A-F248-11E8-B48F-1D18A9856A87
  last_name: Bauer
  orcid: 0000-0002-9683-0724
- first_name: Olivier
  full_name: Devillers, Olivier
  last_name: Devillers
- first_name: Marc
  full_name: Glisse, Marc
  last_name: Glisse
- first_name: André
  full_name: Lieutier, André
  last_name: Lieutier
citation:
  ama: 'Attali D, Bauer U, Devillers O, Glisse M, Lieutier A. Homological reconstruction
    and simplification in R3. <i>Computational Geometry: Theory and Applications</i>.
    2015;48(8):606-621. doi:<a href="https://doi.org/10.1016/j.comgeo.2014.08.010">10.1016/j.comgeo.2014.08.010</a>'
  apa: 'Attali, D., Bauer, U., Devillers, O., Glisse, M., &#38; Lieutier, A. (2015).
    Homological reconstruction and simplification in R3. <i>Computational Geometry:
    Theory and Applications</i>. Elsevier. <a href="https://doi.org/10.1016/j.comgeo.2014.08.010">https://doi.org/10.1016/j.comgeo.2014.08.010</a>'
  chicago: 'Attali, Dominique, Ulrich Bauer, Olivier Devillers, Marc Glisse, and André
    Lieutier. “Homological Reconstruction and Simplification in R3.” <i>Computational
    Geometry: Theory and Applications</i>. Elsevier, 2015. <a href="https://doi.org/10.1016/j.comgeo.2014.08.010">https://doi.org/10.1016/j.comgeo.2014.08.010</a>.'
  ieee: 'D. Attali, U. Bauer, O. Devillers, M. Glisse, and A. Lieutier, “Homological
    reconstruction and simplification in R3,” <i>Computational Geometry: Theory and
    Applications</i>, vol. 48, no. 8. Elsevier, pp. 606–621, 2015.'
  ista: 'Attali D, Bauer U, Devillers O, Glisse M, Lieutier A. 2015. Homological reconstruction
    and simplification in R3. Computational Geometry: Theory and Applications. 48(8),
    606–621.'
  mla: 'Attali, Dominique, et al. “Homological Reconstruction and Simplification in
    R3.” <i>Computational Geometry: Theory and Applications</i>, vol. 48, no. 8, Elsevier,
    2015, pp. 606–21, doi:<a href="https://doi.org/10.1016/j.comgeo.2014.08.010">10.1016/j.comgeo.2014.08.010</a>.'
  short: 'D. Attali, U. Bauer, O. Devillers, M. Glisse, A. Lieutier, Computational
    Geometry: Theory and Applications 48 (2015) 606–621.'
date_created: 2018-12-11T11:54:06Z
date_published: 2015-06-03T00:00:00Z
date_updated: 2023-02-23T10:59:19Z
day: '03'
department:
- _id: HeEd
doi: 10.1016/j.comgeo.2014.08.010
ec_funded: 1
intvolume: '        48'
issue: '8'
language:
- iso: eng
month: '06'
oa_version: None
page: 606 - 621
project:
- _id: 255D761E-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '318493'
  name: Topological Complex Systems
publication: 'Computational Geometry: Theory and Applications'
publication_status: published
publisher: Elsevier
publist_id: '5305'
quality_controlled: '1'
related_material:
  record:
  - id: '2812'
    relation: earlier_version
    status: public
scopus_import: 1
status: public
title: Homological reconstruction and simplification in R3
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 48
year: '2015'
...
---
_id: '1828'
abstract:
- lang: eng
  text: We construct a non-linear Markov process connected with a biological model
    of a bacterial genome recombination. The description of invariant measures of
    this process gives us the solution of one problem in elementary probability theory.
article_processing_charge: No
author:
- first_name: Arseniy
  full_name: Akopyan, Arseniy
  id: 430D2C90-F248-11E8-B48F-1D18A9856A87
  last_name: Akopyan
  orcid: 0000-0002-2548-617X
- first_name: Sergey
  full_name: Pirogov, Sergey
  last_name: Pirogov
- first_name: Aleksandr
  full_name: Rybko, Aleksandr
  last_name: Rybko
citation:
  ama: Akopyan A, Pirogov S, Rybko A. Invariant measures of genetic recombination
    process. <i>Journal of Statistical Physics</i>. 2015;160(1):163-167. doi:<a href="https://doi.org/10.1007/s10955-015-1238-5">10.1007/s10955-015-1238-5</a>
  apa: Akopyan, A., Pirogov, S., &#38; Rybko, A. (2015). Invariant measures of genetic
    recombination process. <i>Journal of Statistical Physics</i>. Springer. <a href="https://doi.org/10.1007/s10955-015-1238-5">https://doi.org/10.1007/s10955-015-1238-5</a>
  chicago: Akopyan, Arseniy, Sergey Pirogov, and Aleksandr Rybko. “Invariant Measures
    of Genetic Recombination Process.” <i>Journal of Statistical Physics</i>. Springer,
    2015. <a href="https://doi.org/10.1007/s10955-015-1238-5">https://doi.org/10.1007/s10955-015-1238-5</a>.
  ieee: A. Akopyan, S. Pirogov, and A. Rybko, “Invariant measures of genetic recombination
    process,” <i>Journal of Statistical Physics</i>, vol. 160, no. 1. Springer, pp.
    163–167, 2015.
  ista: Akopyan A, Pirogov S, Rybko A. 2015. Invariant measures of genetic recombination
    process. Journal of Statistical Physics. 160(1), 163–167.
  mla: Akopyan, Arseniy, et al. “Invariant Measures of Genetic Recombination Process.”
    <i>Journal of Statistical Physics</i>, vol. 160, no. 1, Springer, 2015, pp. 163–67,
    doi:<a href="https://doi.org/10.1007/s10955-015-1238-5">10.1007/s10955-015-1238-5</a>.
  short: A. Akopyan, S. Pirogov, A. Rybko, Journal of Statistical Physics 160 (2015)
    163–167.
date_created: 2018-12-11T11:54:14Z
date_published: 2015-07-01T00:00:00Z
date_updated: 2021-01-12T06:53:28Z
day: '01'
department:
- _id: HeEd
doi: 10.1007/s10955-015-1238-5
ec_funded: 1
intvolume: '       160'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: arxiv.org/abs/1406.5313
month: '07'
oa: 1
oa_version: Preprint
page: 163 - 167
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
publication: Journal of Statistical Physics
publication_status: published
publisher: Springer
publist_id: '5276'
quality_controlled: '1'
scopus_import: 1
status: public
title: Invariant measures of genetic recombination process
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 160
year: '2015'
...
---
_id: '1938'
abstract:
- lang: eng
  text: 'We numerically investigate the distribution of extrema of ''chaotic'' Laplacian
    eigenfunctions on two-dimensional manifolds. Our contribution is two-fold: (a)
    we count extrema on grid graphs with a small number of randomly added edges and
    show the behavior to coincide with the 1957 prediction of Longuet-Higgins for
    the continuous case and (b) we compute the regularity of their spatial distribution
    using discrepancy, which is a classical measure from the theory of Monte Carlo
    integration. The first part suggests that grid graphs with randomly added edges
    should behave like two-dimensional surfaces with ergodic geodesic flow; in the
    second part we show that the extrema are more regularly distributed in space than
    the grid Z2.'
acknowledgement: "F.P. was supported by the Graduate School of IST Austria. S.S. was
  partially supported by CRC1060 of the DFG\r\nThe authors thank Olga Symonova and
  Michael Kerber for sharing their implementation of the persistence algorithm. "
author:
- first_name: Florian
  full_name: Pausinger, Florian
  id: 2A77D7A2-F248-11E8-B48F-1D18A9856A87
  last_name: Pausinger
  orcid: 0000-0002-8379-3768
- first_name: Stefan
  full_name: Steinerberger, Stefan
  last_name: Steinerberger
citation:
  ama: Pausinger F, Steinerberger S. On the distribution of local extrema in quantum
    chaos. <i>Physics Letters, Section A</i>. 2015;379(6):535-541. doi:<a href="https://doi.org/10.1016/j.physleta.2014.12.010">10.1016/j.physleta.2014.12.010</a>
  apa: Pausinger, F., &#38; Steinerberger, S. (2015). On the distribution of local
    extrema in quantum chaos. <i>Physics Letters, Section A</i>. Elsevier. <a href="https://doi.org/10.1016/j.physleta.2014.12.010">https://doi.org/10.1016/j.physleta.2014.12.010</a>
  chicago: Pausinger, Florian, and Stefan Steinerberger. “On the Distribution of Local
    Extrema in Quantum Chaos.” <i>Physics Letters, Section A</i>. Elsevier, 2015.
    <a href="https://doi.org/10.1016/j.physleta.2014.12.010">https://doi.org/10.1016/j.physleta.2014.12.010</a>.
  ieee: F. Pausinger and S. Steinerberger, “On the distribution of local extrema in
    quantum chaos,” <i>Physics Letters, Section A</i>, vol. 379, no. 6. Elsevier,
    pp. 535–541, 2015.
  ista: Pausinger F, Steinerberger S. 2015. On the distribution of local extrema in
    quantum chaos. Physics Letters, Section A. 379(6), 535–541.
  mla: Pausinger, Florian, and Stefan Steinerberger. “On the Distribution of Local
    Extrema in Quantum Chaos.” <i>Physics Letters, Section A</i>, vol. 379, no. 6,
    Elsevier, 2015, pp. 535–41, doi:<a href="https://doi.org/10.1016/j.physleta.2014.12.010">10.1016/j.physleta.2014.12.010</a>.
  short: F. Pausinger, S. Steinerberger, Physics Letters, Section A 379 (2015) 535–541.
date_created: 2018-12-11T11:54:49Z
date_published: 2015-03-06T00:00:00Z
date_updated: 2021-01-12T06:54:12Z
day: '06'
department:
- _id: HeEd
doi: 10.1016/j.physleta.2014.12.010
intvolume: '       379'
issue: '6'
language:
- iso: eng
month: '03'
oa_version: None
page: 535 - 541
publication: Physics Letters, Section A
publication_status: published
publisher: Elsevier
publist_id: '5152'
quality_controlled: '1'
scopus_import: 1
status: public
title: On the distribution of local extrema in quantum chaos
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 379
year: '2015'
...
---
_id: '2035'
abstract:
- lang: eng
  text: "Considering a continuous self-map and the induced endomorphism on homology,
    we study the eigenvalues and eigenspaces of the latter. Taking a filtration of
    representations, we define the persistence of the eigenspaces, effectively introducing
    a hierarchical organization of the map. The algorithm that computes this information
    for a finite sample is proved to be stable, and to give the correct answer for
    a sufficiently dense sample. Results computed with an implementation of the algorithm
    provide evidence of its practical utility.\r\n"
acknowledgement: This research is partially supported by the Toposys project FP7-ICT-318493-STREP,
  by ESF under the ACAT Research Network Programme, by the Russian Government under
  mega project 11.G34.31.0053, and by the Polish National Science Center under Grant
  No. N201 419639.
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Grzegorz
  full_name: Jablonski, Grzegorz
  id: 4483EF78-F248-11E8-B48F-1D18A9856A87
  last_name: Jablonski
  orcid: 0000-0002-3536-9866
- first_name: Marian
  full_name: Mrozek, Marian
  last_name: Mrozek
citation:
  ama: Edelsbrunner H, Jablonski G, Mrozek M. The persistent homology of a self-map.
    <i>Foundations of Computational Mathematics</i>. 2015;15(5):1213-1244. doi:<a
    href="https://doi.org/10.1007/s10208-014-9223-y">10.1007/s10208-014-9223-y</a>
  apa: Edelsbrunner, H., Jablonski, G., &#38; Mrozek, M. (2015). The persistent homology
    of a self-map. <i>Foundations of Computational Mathematics</i>. Springer. <a href="https://doi.org/10.1007/s10208-014-9223-y">https://doi.org/10.1007/s10208-014-9223-y</a>
  chicago: Edelsbrunner, Herbert, Grzegorz Jablonski, and Marian Mrozek. “The Persistent
    Homology of a Self-Map.” <i>Foundations of Computational Mathematics</i>. Springer,
    2015. <a href="https://doi.org/10.1007/s10208-014-9223-y">https://doi.org/10.1007/s10208-014-9223-y</a>.
  ieee: H. Edelsbrunner, G. Jablonski, and M. Mrozek, “The persistent homology of
    a self-map,” <i>Foundations of Computational Mathematics</i>, vol. 15, no. 5.
    Springer, pp. 1213–1244, 2015.
  ista: Edelsbrunner H, Jablonski G, Mrozek M. 2015. The persistent homology of a
    self-map. Foundations of Computational Mathematics. 15(5), 1213–1244.
  mla: Edelsbrunner, Herbert, et al. “The Persistent Homology of a Self-Map.” <i>Foundations
    of Computational Mathematics</i>, vol. 15, no. 5, Springer, 2015, pp. 1213–44,
    doi:<a href="https://doi.org/10.1007/s10208-014-9223-y">10.1007/s10208-014-9223-y</a>.
  short: H. Edelsbrunner, G. Jablonski, M. Mrozek, Foundations of Computational Mathematics
    15 (2015) 1213–1244.
date_created: 2018-12-11T11:55:20Z
date_published: 2015-10-01T00:00:00Z
date_updated: 2021-01-12T06:54:53Z
day: '01'
ddc:
- '000'
department:
- _id: HeEd
doi: 10.1007/s10208-014-9223-y
ec_funded: 1
file:
- access_level: open_access
  checksum: 3566f3a8b0c1bc550e62914a88c584ff
  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:08:10Z
  date_updated: 2020-07-14T12:45:26Z
  file_id: '4670'
  file_name: IST-2016-486-v1+1_s10208-014-9223-y.pdf
  file_size: 1317546
  relation: main_file
file_date_updated: 2020-07-14T12:45:26Z
has_accepted_license: '1'
intvolume: '        15'
issue: '5'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: 1213 - 1244
project:
- _id: 255D761E-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '318493'
  name: Topological Complex Systems
publication: Foundations of Computational Mathematics
publication_status: published
publisher: Springer
publist_id: '5022'
pubrep_id: '486'
quality_controlled: '1'
scopus_import: 1
status: public
title: The persistent homology of a self-map
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 15
year: '2015'
...
---
_id: '1483'
abstract:
- lang: eng
  text: Topological data analysis offers a rich source of valuable information to
    study vision problems. Yet, so far we lack a theoretically sound connection to
    popular kernel-based learning techniques, such as kernel SVMs or kernel PCA. In
    this work, we establish such a connection by designing a multi-scale kernel for
    persistence diagrams, a stable summary representation of topological features
    in data. We show that this kernel is positive definite and prove its stability
    with respect to the 1-Wasserstein distance. Experiments on two benchmark datasets
    for 3D shape classification/retrieval and texture recognition show considerable
    performance gains of the proposed method compared to an alternative approach that
    is based on the recently introduced persistence landscapes.
author:
- first_name: Jan
  full_name: Reininghaus, Jan
  id: 4505473A-F248-11E8-B48F-1D18A9856A87
  last_name: Reininghaus
- first_name: Stefan
  full_name: Huber, Stefan
  id: 4700A070-F248-11E8-B48F-1D18A9856A87
  last_name: Huber
  orcid: 0000-0002-8871-5814
- first_name: Ulrich
  full_name: Bauer, Ulrich
  id: 2ADD483A-F248-11E8-B48F-1D18A9856A87
  last_name: Bauer
  orcid: 0000-0002-9683-0724
- first_name: Roland
  full_name: Kwitt, Roland
  last_name: Kwitt
citation:
  ama: 'Reininghaus J, Huber S, Bauer U, Kwitt R. A stable multi-scale kernel for
    topological machine learning. In: IEEE; 2015:4741-4748. doi:<a href="https://doi.org/10.1109/CVPR.2015.7299106">10.1109/CVPR.2015.7299106</a>'
  apa: 'Reininghaus, J., Huber, S., Bauer, U., &#38; Kwitt, R. (2015). A stable multi-scale
    kernel for topological machine learning (pp. 4741–4748). Presented at the CVPR:
    Computer Vision and Pattern Recognition, Boston, MA, USA: IEEE. <a href="https://doi.org/10.1109/CVPR.2015.7299106">https://doi.org/10.1109/CVPR.2015.7299106</a>'
  chicago: Reininghaus, Jan, Stefan Huber, Ulrich Bauer, and Roland Kwitt. “A Stable
    Multi-Scale Kernel for Topological Machine Learning,” 4741–48. IEEE, 2015. <a
    href="https://doi.org/10.1109/CVPR.2015.7299106">https://doi.org/10.1109/CVPR.2015.7299106</a>.
  ieee: 'J. Reininghaus, S. Huber, U. Bauer, and R. Kwitt, “A stable multi-scale kernel
    for topological machine learning,” presented at the CVPR: Computer Vision and
    Pattern Recognition, Boston, MA, USA, 2015, pp. 4741–4748.'
  ista: 'Reininghaus J, Huber S, Bauer U, Kwitt R. 2015. A stable multi-scale kernel
    for topological machine learning. CVPR: Computer Vision and Pattern Recognition,
    4741–4748.'
  mla: Reininghaus, Jan, et al. <i>A Stable Multi-Scale Kernel for Topological Machine
    Learning</i>. IEEE, 2015, pp. 4741–48, doi:<a href="https://doi.org/10.1109/CVPR.2015.7299106">10.1109/CVPR.2015.7299106</a>.
  short: J. Reininghaus, S. Huber, U. Bauer, R. Kwitt, in:, IEEE, 2015, pp. 4741–4748.
conference:
  end_date: 2015-06-12
  location: Boston, MA, USA
  name: 'CVPR: Computer Vision and Pattern Recognition'
  start_date: 2015-06-07
date_created: 2018-12-11T11:52:17Z
date_published: 2015-10-14T00:00:00Z
date_updated: 2021-01-12T06:51:03Z
day: '14'
department:
- _id: HeEd
doi: 10.1109/CVPR.2015.7299106
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://arxiv.org/abs/1412.6821
month: '10'
oa: 1
oa_version: Preprint
page: 4741 - 4748
publication_identifier:
  eisbn:
  - '978-1-4673-6964-0 '
publication_status: published
publisher: IEEE
publist_id: '5709'
scopus_import: 1
status: public
title: A stable multi-scale kernel for topological machine learning
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
year: '2015'
...
---
_id: '1495'
abstract:
- lang: eng
  text: 'Motivated by biological questions, we study configurations of equal-sized
    disks in the Euclidean plane that neither pack nor cover. Measuring the quality
    by the probability that a random point lies in exactly one disk, we show that
    the regular hexagonal grid gives the maximum among lattice configurations. '
author:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
- first_name: Mabel
  full_name: Iglesias Ham, Mabel
  id: 41B58C0C-F248-11E8-B48F-1D18A9856A87
  last_name: Iglesias Ham
- first_name: Vitaliy
  full_name: Kurlin, Vitaliy
  last_name: Kurlin
citation:
  ama: 'Edelsbrunner H, Iglesias Ham M, Kurlin V. Relaxed disk packing. In: <i>Proceedings
    of the 27th Canadian Conference on Computational Geometry</i>. Vol 2015-August.
    Queen’s University; 2015:128-135.'
  apa: 'Edelsbrunner, H., Iglesias Ham, M., &#38; Kurlin, V. (2015). Relaxed disk
    packing. In <i>Proceedings of the 27th Canadian Conference on Computational Geometry</i>
    (Vol. 2015–August, pp. 128–135). Ontario, Canada: Queen’s University.'
  chicago: Edelsbrunner, Herbert, Mabel Iglesias Ham, and Vitaliy Kurlin. “Relaxed
    Disk Packing.” In <i>Proceedings of the 27th Canadian Conference on Computational
    Geometry</i>, 2015–August:128–35. Queen’s University, 2015.
  ieee: H. Edelsbrunner, M. Iglesias Ham, and V. Kurlin, “Relaxed disk packing,” in
    <i>Proceedings of the 27th Canadian Conference on Computational Geometry</i>,
    Ontario, Canada, 2015, vol. 2015–August, pp. 128–135.
  ista: 'Edelsbrunner H, Iglesias Ham M, Kurlin V. 2015. Relaxed disk packing. Proceedings
    of the 27th Canadian Conference on Computational Geometry. CCCG: Canadian Conference
    on Computational Geometry vol. 2015–August, 128–135.'
  mla: Edelsbrunner, Herbert, et al. “Relaxed Disk Packing.” <i>Proceedings of the
    27th Canadian Conference on Computational Geometry</i>, vol. 2015–August, Queen’s
    University, 2015, pp. 128–35.
  short: H. Edelsbrunner, M. Iglesias Ham, V. Kurlin, in:, Proceedings of the 27th
    Canadian Conference on Computational Geometry, Queen’s University, 2015, pp. 128–135.
conference:
  end_date: 2015-08-12
  location: Ontario, Canada
  name: 'CCCG: Canadian Conference on Computational Geometry'
  start_date: 2015-08-10
date_created: 2018-12-11T11:52:21Z
date_published: 2015-08-01T00:00:00Z
date_updated: 2021-01-12T06:51:09Z
day: '01'
department:
- _id: HeEd
ec_funded: 1
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1505.03402
month: '08'
oa: 1
oa_version: Submitted Version
page: 128-135
project:
- _id: 255D761E-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '318493'
  name: Topological Complex Systems
publication: Proceedings of the 27th Canadian Conference on Computational Geometry
publication_status: published
publisher: Queen's University
publist_id: '5684'
quality_controlled: '1'
scopus_import: 1
status: public
title: Relaxed disk packing
type: conference
user_id: 3E5EF7F0-F248-11E8-B48F-1D18A9856A87
volume: 2015-August
year: '2015'
...
---
_id: '1510'
abstract:
- lang: eng
  text: 'The concept of well group in a special but important case captures homological
    properties of the zero set of a continuous map f from K to R^n on a compact space
    K that are invariant with respect to perturbations of f. The perturbations are
    arbitrary continuous maps within L_infty distance r from f for a given r &gt;
    0. The main drawback of the approach is that the computability of well groups
    was shown only when dim K = n or n = 1. Our contribution to the theory of well
    groups is twofold: on the one hand we improve on the computability issue, but
    on the other hand we present a range of examples where the well groups are incomplete
    invariants, that is, fail to capture certain important robust properties of the
    zero set. For the first part, we identify a computable subgroup of the well group
    that is obtained by cap product with the pullback of the orientation of R^n by
    f. In other words, well groups can be algorithmically approximated from below.
    When f is smooth and dim K &lt; 2n-2, our approximation of the (dim K-n)th well
    group is exact. For the second part, we find examples of maps f, f'' from K to
    R^n with all well groups isomorphic but whose perturbations have different zero
    sets. We discuss on a possible replacement of the well groups of vector valued
    maps by an invariant of a better descriptive power and computability status. '
alternative_title:
- LIPIcs
author:
- first_name: Peter
  full_name: Franek, Peter
  id: 473294AE-F248-11E8-B48F-1D18A9856A87
  last_name: Franek
- first_name: Marek
  full_name: Krcál, Marek
  id: 33E21118-F248-11E8-B48F-1D18A9856A87
  last_name: Krcál
citation:
  ama: 'Franek P, Krcál M. On computability and triviality of well groups. In: Vol
    34. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2015:842-856. doi:<a href="https://doi.org/10.4230/LIPIcs.SOCG.2015.842">10.4230/LIPIcs.SOCG.2015.842</a>'
  apa: 'Franek, P., &#38; Krcál, M. (2015). On computability and triviality of well
    groups (Vol. 34, pp. 842–856). Presented at the SoCG: Symposium on Computational
    Geometry, Eindhoven, Netherlands: Schloss Dagstuhl - Leibniz-Zentrum für Informatik.
    <a href="https://doi.org/10.4230/LIPIcs.SOCG.2015.842">https://doi.org/10.4230/LIPIcs.SOCG.2015.842</a>'
  chicago: Franek, Peter, and Marek Krcál. “On Computability and Triviality of Well
    Groups,” 34:842–56. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2015. <a
    href="https://doi.org/10.4230/LIPIcs.SOCG.2015.842">https://doi.org/10.4230/LIPIcs.SOCG.2015.842</a>.
  ieee: 'P. Franek and M. Krcál, “On computability and triviality of well groups,”
    presented at the SoCG: Symposium on Computational Geometry, Eindhoven, Netherlands,
    2015, vol. 34, pp. 842–856.'
  ista: 'Franek P, Krcál M. 2015. On computability and triviality of well groups.
    SoCG: Symposium on Computational Geometry, LIPIcs, vol. 34, 842–856.'
  mla: Franek, Peter, and Marek Krcál. <i>On Computability and Triviality of Well
    Groups</i>. Vol. 34, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2015,
    pp. 842–56, doi:<a href="https://doi.org/10.4230/LIPIcs.SOCG.2015.842">10.4230/LIPIcs.SOCG.2015.842</a>.
  short: P. Franek, M. Krcál, in:, Schloss Dagstuhl - Leibniz-Zentrum für Informatik,
    2015, pp. 842–856.
conference:
  end_date: 2015-06-25
  location: Eindhoven, Netherlands
  name: 'SoCG: Symposium on Computational Geometry'
  start_date: 2015-06-22
date_created: 2018-12-11T11:52:26Z
date_published: 2015-06-11T00:00:00Z
date_updated: 2023-02-21T17:02:57Z
day: '11'
ddc:
- '510'
department:
- _id: UlWa
- _id: HeEd
doi: 10.4230/LIPIcs.SOCG.2015.842
ec_funded: 1
file:
- access_level: open_access
  checksum: 49eb5021caafaabe5356c65b9c5f8c9c
  content_type: application/pdf
  creator: system
  date_created: 2018-12-12T10:13:19Z
  date_updated: 2020-07-14T12:44:59Z
  file_id: '5001'
  file_name: IST-2016-503-v1+1_32.pdf
  file_size: 623563
  relation: main_file
file_date_updated: 2020-07-14T12:44:59Z
has_accepted_license: '1'
intvolume: '        34'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: 842 - 856
project:
- _id: 25681D80-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '291734'
  name: International IST Postdoc Fellowship Programme
publication_status: published
publisher: Schloss Dagstuhl - Leibniz-Zentrum für Informatik
publist_id: '5667'
pubrep_id: '503'
quality_controlled: '1'
related_material:
  record:
  - id: '1408'
    relation: later_version
    status: public
scopus_import: 1
status: public
title: On computability and triviality of well groups
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: conference
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 34
year: '2015'
...
---
_id: '1531'
abstract:
- lang: eng
  text: The Heat Kernel Signature (HKS) is a scalar quantity which is derived from
    the heat kernel of a given shape. Due to its robustness, isometry invariance,
    and multiscale nature, it has been successfully applied in many geometric applications.
    From a more general point of view, the HKS can be considered as a descriptor of
    the metric of a Riemannian manifold. Given a symmetric positive definite tensor
    field we may interpret it as the metric of some Riemannian manifold and thereby
    apply the HKS to visualize and analyze the given tensor data. In this paper, we
    propose a generalization of this approach that enables the treatment of indefinite
    tensor fields, like the stress tensor, by interpreting them as a generator of
    a positive definite tensor field. To investigate the usefulness of this approach
    we consider the stress tensor from the two-point-load model example and from a
    mechanical work piece.
alternative_title:
- Mathematics and Visualization
article_processing_charge: No
author:
- first_name: Valentin
  full_name: Zobel, Valentin
  last_name: Zobel
- first_name: Jan
  full_name: Reininghaus, Jan
  id: 4505473A-F248-11E8-B48F-1D18A9856A87
  last_name: Reininghaus
- first_name: Ingrid
  full_name: Hotz, Ingrid
  last_name: Hotz
citation:
  ama: 'Zobel V, Reininghaus J, Hotz I. Visualizing symmetric indefinite 2D tensor
    fields using The Heat Kernel Signature. In: Hotz I, Schultz T, eds. <i>Visualization
    and Processing of Higher Order Descriptors for Multi-Valued Data</i>. Vol 40.
    1st ed. Springer; 2015:257-267. doi:<a href="https://doi.org/10.1007/978-3-319-15090-1_13">10.1007/978-3-319-15090-1_13</a>'
  apa: Zobel, V., Reininghaus, J., &#38; Hotz, I. (2015). Visualizing symmetric indefinite
    2D tensor fields using The Heat Kernel Signature. In I. Hotz &#38; T. Schultz
    (Eds.), <i>Visualization and Processing of Higher Order Descriptors for Multi-Valued
    Data</i> (1st ed., Vol. 40, pp. 257–267). Springer. <a href="https://doi.org/10.1007/978-3-319-15090-1_13">https://doi.org/10.1007/978-3-319-15090-1_13</a>
  chicago: Zobel, Valentin, Jan Reininghaus, and Ingrid Hotz. “Visualizing Symmetric
    Indefinite 2D Tensor Fields Using The Heat Kernel Signature.” In <i>Visualization
    and Processing of Higher Order Descriptors for Multi-Valued Data</i>, edited by
    Ingrid Hotz and Thomas Schultz, 1st ed., 40:257–67. Springer, 2015. <a href="https://doi.org/10.1007/978-3-319-15090-1_13">https://doi.org/10.1007/978-3-319-15090-1_13</a>.
  ieee: V. Zobel, J. Reininghaus, and I. Hotz, “Visualizing symmetric indefinite 2D
    tensor fields using The Heat Kernel Signature,” in <i>Visualization and Processing
    of Higher Order Descriptors for Multi-Valued Data</i>, 1st ed., vol. 40, I. Hotz
    and T. Schultz, Eds. Springer, 2015, pp. 257–267.
  ista: 'Zobel V, Reininghaus J, Hotz I. 2015.Visualizing symmetric indefinite 2D
    tensor fields using The Heat Kernel Signature. In: Visualization and Processing
    of Higher Order Descriptors for Multi-Valued Data. Mathematics and Visualization,
    vol. 40, 257–267.'
  mla: Zobel, Valentin, et al. “Visualizing Symmetric Indefinite 2D Tensor Fields
    Using The Heat Kernel Signature.” <i>Visualization and Processing of Higher Order
    Descriptors for Multi-Valued Data</i>, edited by Ingrid Hotz and Thomas Schultz,
    1st ed., vol. 40, Springer, 2015, pp. 257–67, doi:<a href="https://doi.org/10.1007/978-3-319-15090-1_13">10.1007/978-3-319-15090-1_13</a>.
  short: V. Zobel, J. Reininghaus, I. Hotz, in:, I. Hotz, T. Schultz (Eds.), Visualization
    and Processing of Higher Order Descriptors for Multi-Valued Data, 1st ed., Springer,
    2015, pp. 257–267.
date_created: 2018-12-11T11:52:33Z
date_published: 2015-01-01T00:00:00Z
date_updated: 2022-06-10T09:50:14Z
day: '01'
department:
- _id: HeEd
doi: 10.1007/978-3-319-15090-1_13
edition: '1'
editor:
- first_name: Ingrid
  full_name: Hotz, Ingrid
  last_name: Hotz
- first_name: Thomas
  full_name: Schultz, Thomas
  last_name: Schultz
intvolume: '        40'
language:
- iso: eng
month: '01'
oa_version: None
page: 257 - 267
publication: Visualization and Processing of Higher Order Descriptors for Multi-Valued
  Data
publication_identifier:
  isbn:
  - 978-3-319-15089-5
publication_status: published
publisher: Springer
publist_id: '5640'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Visualizing symmetric indefinite 2D tensor fields using The Heat Kernel Signature
type: book_chapter
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 40
year: '2015'
...
---
_id: '1555'
abstract:
- lang: eng
  text: We show that incorporating spatial dispersal of individuals into a simple
    vaccination epidemic model may give rise to a model that exhibits rich dynamical
    behavior. Using an SIVS (susceptible-infected-vaccinated-susceptible) model as
    a basis, we describe the spread of an infectious disease in a population split
    into two regions. In each subpopulation, both forward and backward bifurcations
    can occur. This implies that for disconnected regions the two-patch system may
    admit several steady states. We consider traveling between the regions and investigate
    the impact of spatial dispersal of individuals on the model dynamics. We establish
    conditions for the existence of multiple nontrivial steady states in the system,
    and we study the structure of the equilibria. The mathematical analysis reveals
    an unusually rich dynamical behavior, not normally found in the simple epidemic
    models. In addition to the disease-free equilibrium, eight endemic equilibria
    emerge from backward transcritical and saddle-node bifurcation points, forming
    an interesting bifurcation diagram. Stability of steady states, their bifurcations,
    and the global dynamics are investigated with analytical tools, numerical simulations,
    and rigorous set-oriented numerical computations.
acknowledgement: Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg,
  Austria (pawel.pilarczyk@ist.ac.at). This author’s work was partially supported
  by the People Programme (Marie Curie Actions) of the European Union’s Seventh Framework
  Programme (FP7/2007-2013) under REA grant agreement 622033, by Fundo Europeu de
  Desenvolvimento Regional (FEDER) through COMPETE—Programa Operacional Factores de
  Competitividade (POFC), by the Portuguese national funds through Funda ̧caoparaaCiˆencia
  e a Tecnologia (FCT) in the framework of the research project FCOMP-01-0124-FEDER-010645
  (ref. FCT PTDC/MAT/098871/2008), and by European Research Council through StG 259559
  in the framework of the EPIDELAY project.
article_processing_charge: No
article_type: original
author:
- first_name: Diána
  full_name: Knipl, Diána
  last_name: Knipl
- first_name: Pawel
  full_name: Pilarczyk, Pawel
  id: 3768D56A-F248-11E8-B48F-1D18A9856A87
  last_name: Pilarczyk
- first_name: Gergely
  full_name: Röst, Gergely
  last_name: Röst
citation:
  ama: Knipl D, Pilarczyk P, Röst G. Rich bifurcation structure in a two patch vaccination
    model. <i>SIAM Journal on Applied Dynamical Systems</i>. 2015;14(2):980-1017.
    doi:<a href="https://doi.org/10.1137/140993934">10.1137/140993934</a>
  apa: Knipl, D., Pilarczyk, P., &#38; Röst, G. (2015). Rich bifurcation structure
    in a two patch vaccination model. <i>SIAM Journal on Applied Dynamical Systems</i>.
    Society for Industrial and Applied Mathematics . <a href="https://doi.org/10.1137/140993934">https://doi.org/10.1137/140993934</a>
  chicago: Knipl, Diána, Pawel Pilarczyk, and Gergely Röst. “Rich Bifurcation Structure
    in a Two Patch Vaccination Model.” <i>SIAM Journal on Applied Dynamical Systems</i>.
    Society for Industrial and Applied Mathematics , 2015. <a href="https://doi.org/10.1137/140993934">https://doi.org/10.1137/140993934</a>.
  ieee: D. Knipl, P. Pilarczyk, and G. Röst, “Rich bifurcation structure in a two
    patch vaccination model,” <i>SIAM Journal on Applied Dynamical Systems</i>, vol.
    14, no. 2. Society for Industrial and Applied Mathematics , pp. 980–1017, 2015.
  ista: Knipl D, Pilarczyk P, Röst G. 2015. Rich bifurcation structure in a two patch
    vaccination model. SIAM Journal on Applied Dynamical Systems. 14(2), 980–1017.
  mla: Knipl, Diána, et al. “Rich Bifurcation Structure in a Two Patch Vaccination
    Model.” <i>SIAM Journal on Applied Dynamical Systems</i>, vol. 14, no. 2, Society
    for Industrial and Applied Mathematics , 2015, pp. 980–1017, doi:<a href="https://doi.org/10.1137/140993934">10.1137/140993934</a>.
  short: D. Knipl, P. Pilarczyk, G. Röst, SIAM Journal on Applied Dynamical Systems
    14 (2015) 980–1017.
date_created: 2018-12-11T11:52:42Z
date_published: 2015-01-01T00:00:00Z
date_updated: 2021-01-12T06:51:34Z
day: '01'
ddc:
- '510'
department:
- _id: HeEd
doi: 10.1137/140993934
ec_funded: 1
intvolume: '        14'
issue: '2'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://discovery.ucl.ac.uk/1473750/1/99393.pdf
month: '01'
oa: 1
oa_version: Published Version
page: 980 - 1017
project:
- _id: 255F06BE-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '622033'
  name: Persistent Homology - Images, Data and Maps
publication: SIAM Journal on Applied Dynamical Systems
publication_identifier:
  eissn:
  - 1536-0040
publication_status: published
publisher: 'Society for Industrial and Applied Mathematics '
publist_id: '5616'
quality_controlled: '1'
scopus_import: 1
status: public
title: Rich bifurcation structure in a two patch vaccination model
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 14
year: '2015'
...
