---
_id: '14226'
abstract:
- lang: eng
  text: "We introduce the notion of a Faustian interchange in a 1-parameter family
    of smooth\r\nfunctions to generalize the medial axis to critical points of index
    larger than 0.\r\nWe construct and implement a general purpose algorithm for approximating
    such\r\ngeneralized medial axes."
alternative_title:
- ISTA Master's Thesis
article_processing_charge: No
author:
- first_name: Elizabeth R
  full_name: Stephenson, Elizabeth R
  id: 2D04F932-F248-11E8-B48F-1D18A9856A87
  last_name: Stephenson
  orcid: 0000-0002-6862-208X
citation:
  ama: Stephenson ER. Generalizing medial axes with homology switches. 2023. doi:<a
    href="https://doi.org/10.15479/at:ista:14226">10.15479/at:ista:14226</a>
  apa: Stephenson, E. R. (2023). <i>Generalizing medial axes with homology switches</i>.
    Institute of Science and Technology Austria. <a href="https://doi.org/10.15479/at:ista:14226">https://doi.org/10.15479/at:ista:14226</a>
  chicago: Stephenson, Elizabeth R. “Generalizing Medial Axes with Homology Switches.”
    Institute of Science and Technology Austria, 2023. <a href="https://doi.org/10.15479/at:ista:14226">https://doi.org/10.15479/at:ista:14226</a>.
  ieee: E. R. Stephenson, “Generalizing medial axes with homology switches,” Institute
    of Science and Technology Austria, 2023.
  ista: Stephenson ER. 2023. Generalizing medial axes with homology switches. Institute
    of Science and Technology Austria.
  mla: Stephenson, Elizabeth R. <i>Generalizing Medial Axes with Homology Switches</i>.
    Institute of Science and Technology Austria, 2023, doi:<a href="https://doi.org/10.15479/at:ista:14226">10.15479/at:ista:14226</a>.
  short: E.R. Stephenson, Generalizing Medial Axes with Homology Switches, Institute
    of Science and Technology Austria, 2023.
date_created: 2023-08-24T13:01:18Z
date_published: 2023-08-24T00:00:00Z
date_updated: 2024-02-26T23:30:04Z
day: '24'
ddc:
- '500'
degree_awarded: MS
department:
- _id: GradSch
- _id: HeEd
doi: 10.15479/at:ista:14226
file:
- access_level: closed
  checksum: 453caf851d75c3478c10ed09bd242a91
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  creator: cchlebak
  date_created: 2023-08-24T13:02:49Z
  date_updated: 2024-02-26T23:30:03Z
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  file_id: '14227'
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  file_size: 15501411
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  date_created: 2023-08-24T13:03:42Z
  date_updated: 2024-02-26T23:30:03Z
  embargo: 2024-02-25
  file_id: '14228'
  file_name: thesis_pdf_a.pdf
  file_size: 6854783
  relation: main_file
file_date_updated: 2024-02-26T23:30:03Z
has_accepted_license: '1'
language:
- iso: eng
month: '08'
oa: 1
oa_version: Published Version
page: '43'
publication_identifier:
  issn:
  - 2791-4585
publication_status: published
publisher: Institute of Science and Technology Austria
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: Generalizing medial axes with homology switches
type: dissertation
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2023'
...
---
_id: '9056'
abstract:
- lang: eng
  text: "In this thesis we study persistence of multi-covers of Euclidean balls and
    the geometric structures underlying their computation, in particular Delaunay
    mosaics and Voronoi tessellations. The k-fold cover for some discrete input point
    set consists of the space where at least k balls of radius r around the input
    points overlap. Persistence is a notion that captures, in some sense, the topology
    of the shape underlying the input. While persistence is usually computed for the
    union of balls, the k-fold cover is of interest as it captures local density,\r\nand
    thus might approximate the shape of the input better if the input data is noisy.
    To compute persistence of these k-fold covers, we need a discretization that is
    provided by higher-order Delaunay mosaics. We present and implement a simple and
    efficient algorithm for the computation of higher-order Delaunay mosaics, and
    use it to give experimental results for their combinatorial properties. The algorithm
    makes use of a new geometric structure, the rhomboid tiling. It contains the higher-order
    Delaunay mosaics as slices, and by introducing a filtration\r\nfunction on the
    tiling, we also obtain higher-order α-shapes as slices. These allow us to compute
    persistence of the multi-covers for varying radius r; the computation for varying
    k is less straight-foward and involves the rhomboid tiling directly. We apply
    our algorithms to experimental sphere packings to shed light on their structural
    properties. Finally, inspired by periodic structures in packings and materials,
    we propose and implement an algorithm for periodic Delaunay triangulations to
    be integrated into the Computational Geometry Algorithms Library (CGAL), and discuss
    the implications on persistence for periodic data sets."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Georg F
  full_name: Osang, Georg F
  id: 464B40D6-F248-11E8-B48F-1D18A9856A87
  last_name: Osang
  orcid: 0000-0002-8882-5116
citation:
  ama: Osang GF. Multi-cover persistence and Delaunay mosaics. 2021. doi:<a href="https://doi.org/10.15479/AT:ISTA:9056">10.15479/AT:ISTA:9056</a>
  apa: Osang, G. F. (2021). <i>Multi-cover persistence and Delaunay mosaics</i>. Institute
    of Science and Technology Austria, Klosterneuburg. <a href="https://doi.org/10.15479/AT:ISTA:9056">https://doi.org/10.15479/AT:ISTA:9056</a>
  chicago: Osang, Georg F. “Multi-Cover Persistence and Delaunay Mosaics.” Institute
    of Science and Technology Austria, 2021. <a href="https://doi.org/10.15479/AT:ISTA:9056">https://doi.org/10.15479/AT:ISTA:9056</a>.
  ieee: G. F. Osang, “Multi-cover persistence and Delaunay mosaics,” Institute of
    Science and Technology Austria, Klosterneuburg, 2021.
  ista: 'Osang GF. 2021. Multi-cover persistence and Delaunay mosaics. Klosterneuburg:
    Institute of Science and Technology Austria.'
  mla: Osang, Georg F. <i>Multi-Cover Persistence and Delaunay Mosaics</i>. Institute
    of Science and Technology Austria, 2021, doi:<a href="https://doi.org/10.15479/AT:ISTA:9056">10.15479/AT:ISTA:9056</a>.
  short: G.F. Osang, Multi-Cover Persistence and Delaunay Mosaics, Institute of Science
    and Technology Austria, 2021.
date_created: 2021-02-02T14:11:06Z
date_published: 2021-02-01T00:00:00Z
date_updated: 2023-09-07T13:29:01Z
day: '01'
ddc:
- '006'
- '514'
- '516'
degree_awarded: PhD
department:
- _id: HeEd
- _id: GradSch
doi: 10.15479/AT:ISTA:9056
file:
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  creator: patrickd
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  date_updated: 2021-02-03T10:37:28Z
  file_id: '9063'
  file_name: thesis_source.zip
  file_size: 13446994
  relation: source_file
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  checksum: 9cc8af266579a464385bbe2aff6af606
  content_type: application/pdf
  creator: patrickd
  date_created: 2021-02-02T14:09:18Z
  date_updated: 2021-02-02T14:09:18Z
  file_id: '9064'
  file_name: thesis_pdfA2b.pdf
  file_size: 5210329
  relation: main_file
  success: 1
file_date_updated: 2021-02-03T10:37:28Z
has_accepted_license: '1'
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '02'
oa: 1
oa_version: Published Version
page: '134'
place: Klosterneuburg
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '187'
    relation: part_of_dissertation
    status: public
  - id: '8703'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: Multi-cover persistence and Delaunay mosaics
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  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...
---
_id: '7944'
abstract:
- lang: eng
  text: "This thesis considers two examples of reconfiguration problems: flipping
    edges in edge-labelled triangulations of planar point sets and swapping labelled
    tokens placed on vertices of a graph. In both cases the studied structures – all
    the triangulations of a given point set or all token placements on a given graph
    – can be thought of as vertices of the so-called reconfiguration graph, in which
    two vertices are adjacent if the corresponding structures differ by a single elementary
    operation – by a flip of a diagonal in a triangulation or by a swap of tokens
    on adjacent vertices, respectively. We study the reconfiguration of one instance
    of a structure into another via (shortest) paths in the reconfiguration graph.\r\n\r\nFor
    triangulations of point sets in which each edge has a unique label and a flip
    transfers the label from the removed edge to the new edge, we prove a polynomial-time
    testable condition, called the Orbit Theorem, that characterizes when two triangulations
    of the same point set lie in the same connected component of the reconfiguration
    graph. The condition was first conjectured by Bose, Lubiw, Pathak and Verdonschot.
    We additionally provide a polynomial time algorithm that computes a reconfiguring
    flip sequence, if it exists. Our proof of the Orbit Theorem uses topological properties
    of a certain high-dimensional cell complex that has the usual reconfiguration
    graph as its 1-skeleton.\r\n\r\nIn the context of token swapping on a tree graph,
    we make partial progress on the problem of finding shortest reconfiguration sequences.
    We disprove the so-called Happy Leaf Conjecture and demonstrate the importance
    of swapping tokens that are already placed at the correct vertices. We also prove
    that a generalization of the problem to weighted coloured token swapping is NP-hard
    on trees but solvable in polynomial time on paths and stars."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Zuzana
  full_name: Masárová, Zuzana
  id: 45CFE238-F248-11E8-B48F-1D18A9856A87
  last_name: Masárová
  orcid: 0000-0002-6660-1322
citation:
  ama: Masárová Z. Reconfiguration problems. 2020. doi:<a href="https://doi.org/10.15479/AT:ISTA:7944">10.15479/AT:ISTA:7944</a>
  apa: Masárová, Z. (2020). <i>Reconfiguration problems</i>. Institute of Science
    and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:7944">https://doi.org/10.15479/AT:ISTA:7944</a>
  chicago: Masárová, Zuzana. “Reconfiguration Problems.” Institute of Science and
    Technology Austria, 2020. <a href="https://doi.org/10.15479/AT:ISTA:7944">https://doi.org/10.15479/AT:ISTA:7944</a>.
  ieee: Z. Masárová, “Reconfiguration problems,” Institute of Science and Technology
    Austria, 2020.
  ista: Masárová Z. 2020. Reconfiguration problems. Institute of Science and Technology
    Austria.
  mla: Masárová, Zuzana. <i>Reconfiguration Problems</i>. Institute of Science and
    Technology Austria, 2020, doi:<a href="https://doi.org/10.15479/AT:ISTA:7944">10.15479/AT:ISTA:7944</a>.
  short: Z. Masárová, Reconfiguration Problems, Institute of Science and Technology
    Austria, 2020.
date_created: 2020-06-08T00:49:46Z
date_published: 2020-06-09T00:00:00Z
date_updated: 2023-09-07T13:17:37Z
day: '09'
ddc:
- '516'
- '514'
degree_awarded: PhD
department:
- _id: HeEd
- _id: UlWa
doi: 10.15479/AT:ISTA:7944
file:
- access_level: open_access
  checksum: df688bc5a82b50baee0b99d25fc7b7f0
  content_type: application/pdf
  creator: zmasarov
  date_created: 2020-06-08T00:34:00Z
  date_updated: 2020-07-14T12:48:05Z
  file_id: '7945'
  file_name: THESIS_Zuzka_Masarova.pdf
  file_size: 13661779
  relation: main_file
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  content_type: application/zip
  creator: zmasarov
  date_created: 2020-06-08T00:35:30Z
  date_updated: 2020-07-14T12:48:05Z
  file_id: '7946'
  file_name: THESIS_Zuzka_Masarova_SOURCE_FILES.zip
  file_size: 32184006
  relation: source_file
file_date_updated: 2020-07-14T12:48:05Z
has_accepted_license: '1'
keyword:
- reconfiguration
- reconfiguration graph
- triangulations
- flip
- constrained triangulations
- shellability
- piecewise-linear balls
- token swapping
- trees
- coloured weighted token swapping
language:
- iso: eng
license: https://creativecommons.org/licenses/by-sa/4.0/
month: '06'
oa: 1
oa_version: Published Version
page: '160'
publication_identifier:
  isbn:
  - 978-3-99078-005-3
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '7950'
    relation: part_of_dissertation
    status: public
  - id: '5986'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Uli
  full_name: Wagner, Uli
  id: 36690CA2-F248-11E8-B48F-1D18A9856A87
  last_name: Wagner
  orcid: 0000-0002-1494-0568
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: Reconfiguration problems
tmp:
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  name: Creative Commons Attribution-ShareAlike 4.0 International Public License (CC
    BY-SA 4.0)
  short: CC BY-SA (4.0)
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '7460'
abstract:
- lang: eng
  text: "Many methods for the reconstruction of shapes from sets of points produce
    ordered simplicial complexes, which are collections of vertices, edges, triangles,
    and their higher-dimensional analogues, called simplices, in which every simplex
    gets assigned a real value measuring its size. This thesis studies ordered simplicial
    complexes, with a focus on their topology, which reflects the connectedness of
    the represented shapes and the presence of holes. We are interested both in understanding
    better the structure of these complexes, as well as in developing algorithms for
    applications.\r\n\r\nFor the Delaunay triangulation, the most popular measure
    for a simplex is the radius of the smallest empty circumsphere. Based on it, we
    revisit Alpha and Wrap complexes and experimentally determine their probabilistic
    properties for random data. Also, we prove the existence of tri-partitions, propose
    algorithms to open and close holes, and extend the concepts from Euclidean to
    Bregman geometries."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Katharina
  full_name: Ölsböck, Katharina
  id: 4D4AA390-F248-11E8-B48F-1D18A9856A87
  last_name: Ölsböck
  orcid: 0000-0002-4672-8297
citation:
  ama: Ölsböck K. The hole system of triangulated shapes. 2020. doi:<a href="https://doi.org/10.15479/AT:ISTA:7460">10.15479/AT:ISTA:7460</a>
  apa: Ölsböck, K. (2020). <i>The hole system of triangulated shapes</i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:7460">https://doi.org/10.15479/AT:ISTA:7460</a>
  chicago: Ölsböck, Katharina. “The Hole System of Triangulated Shapes.” Institute
    of Science and Technology Austria, 2020. <a href="https://doi.org/10.15479/AT:ISTA:7460">https://doi.org/10.15479/AT:ISTA:7460</a>.
  ieee: K. Ölsböck, “The hole system of triangulated shapes,” Institute of Science
    and Technology Austria, 2020.
  ista: Ölsböck K. 2020. The hole system of triangulated shapes. Institute of Science
    and Technology Austria.
  mla: Ölsböck, Katharina. <i>The Hole System of Triangulated Shapes</i>. Institute
    of Science and Technology Austria, 2020, doi:<a href="https://doi.org/10.15479/AT:ISTA:7460">10.15479/AT:ISTA:7460</a>.
  short: K. Ölsböck, The Hole System of Triangulated Shapes, Institute of Science
    and Technology Austria, 2020.
date_created: 2020-02-06T14:56:53Z
date_published: 2020-02-10T00:00:00Z
date_updated: 2023-09-07T13:15:30Z
day: '10'
ddc:
- '514'
degree_awarded: PhD
department:
- _id: HeEd
- _id: GradSch
doi: 10.15479/AT:ISTA:7460
file:
- access_level: open_access
  checksum: 1df9f8c530b443c0e63a3f2e4fde412e
  content_type: application/pdf
  creator: koelsboe
  date_created: 2020-02-06T14:43:54Z
  date_updated: 2020-07-14T12:47:58Z
  file_id: '7461'
  file_name: thesis_ist-final_noack.pdf
  file_size: 76195184
  relation: main_file
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  checksum: 7a52383c812b0be64d3826546509e5a4
  content_type: application/x-zip-compressed
  creator: koelsboe
  date_created: 2020-02-06T14:52:45Z
  date_updated: 2020-07-14T12:47:58Z
  description: latex source files, figures
  file_id: '7462'
  file_name: latex-files.zip
  file_size: 122103715
  relation: source_file
file_date_updated: 2020-07-14T12:47:58Z
has_accepted_license: '1'
keyword:
- shape reconstruction
- hole manipulation
- ordered complexes
- Alpha complex
- Wrap complex
- computational topology
- Bregman geometry
language:
- iso: eng
license: https://creativecommons.org/licenses/by-nc-sa/4.0/
month: '02'
oa: 1
oa_version: Published Version
page: '155'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
  record:
  - id: '6608'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: The hole system of triangulated shapes
tmp:
  image: /images/cc_by_nc_sa.png
  legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode
  name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC
    BY-NC-SA 4.0)
  short: CC BY-NC-SA (4.0)
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2020'
...
---
_id: '201'
abstract:
- lang: eng
  text: 'We describe arrangements of three-dimensional spheres from a geometrical
    and topological point of view. Real data (fitting this setup) often consist of
    soft spheres which show certain degree of deformation while strongly packing against
    each other. In this context, we answer the following questions: If we model a
    soft packing of spheres by hard spheres that are allowed to overlap, can we measure
    the volume in the overlapped areas? Can we be more specific about the overlap
    volume, i.e. quantify how much volume is there covered exactly twice, three times,
    or k times? What would be a good optimization criteria that rule the arrangement
    of soft spheres while making a good use of the available space? Fixing a particular
    criterion, what would be the optimal sphere configuration? The first result of
    this thesis are short formulas for the computation of volumes covered by at least
    k of the balls. The formulas exploit information contained in the order-k Voronoi
    diagrams and its closely related Level-k complex. The used complexes lead to a
    natural generalization into poset diagrams, a theoretical formalism that contains
    the order-k and degree-k diagrams as special cases. In parallel, we define different
    criteria to determine what could be considered an optimal arrangement from a geometrical
    point of view. Fixing a criterion, we find optimal soft packing configurations
    in 2D and 3D where the ball centers lie on a lattice. As a last step, we use tools
    from computational topology on real physical data, to show the potentials of higher-order
    diagrams in the description of melting crystals. The results of the experiments
    leaves us with an open window to apply the theories developed in this thesis in
    real applications.'
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Mabel
  full_name: Iglesias Ham, Mabel
  id: 41B58C0C-F248-11E8-B48F-1D18A9856A87
  last_name: Iglesias Ham
citation:
  ama: Iglesias Ham M. Multiple covers with balls. 2018. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_1026">10.15479/AT:ISTA:th_1026</a>
  apa: Iglesias Ham, M. (2018). <i>Multiple covers with balls</i>. Institute of Science
    and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_1026">https://doi.org/10.15479/AT:ISTA:th_1026</a>
  chicago: Iglesias Ham, Mabel. “Multiple Covers with Balls.” Institute of Science
    and Technology Austria, 2018. <a href="https://doi.org/10.15479/AT:ISTA:th_1026">https://doi.org/10.15479/AT:ISTA:th_1026</a>.
  ieee: M. Iglesias Ham, “Multiple covers with balls,” Institute of Science and Technology
    Austria, 2018.
  ista: Iglesias Ham M. 2018. Multiple covers with balls. Institute of Science and
    Technology Austria.
  mla: Iglesias Ham, Mabel. <i>Multiple Covers with Balls</i>. Institute of Science
    and Technology Austria, 2018, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_1026">10.15479/AT:ISTA:th_1026</a>.
  short: M. Iglesias Ham, Multiple Covers with Balls, Institute of Science and Technology
    Austria, 2018.
date_created: 2018-12-11T11:45:10Z
date_published: 2018-06-11T00:00:00Z
date_updated: 2023-09-07T12:25:32Z
day: '11'
ddc:
- '514'
- '516'
degree_awarded: PhD
department:
- _id: HeEd
doi: 10.15479/AT:ISTA:th_1026
file:
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  checksum: dd699303623e96d1478a6ae07210dd05
  content_type: application/zip
  creator: kschuh
  date_created: 2019-02-05T07:43:31Z
  date_updated: 2020-07-14T12:45:24Z
  file_id: '5918'
  file_name: IST-2018-1025-v2+5_ist-thesis-iglesias-11June2018(1).zip
  file_size: 11827713
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  content_type: application/pdf
  creator: kschuh
  date_created: 2019-02-05T07:43:45Z
  date_updated: 2020-07-14T12:45:24Z
  file_id: '5919'
  file_name: IST-2018-1025-v2+4_ThesisIglesiasFinal11June2018.pdf
  file_size: 4783846
  relation: main_file
file_date_updated: 2020-07-14T12:45:24Z
has_accepted_license: '1'
language:
- iso: eng
month: '06'
oa: 1
oa_version: Published Version
page: '171'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '7712'
pubrep_id: '1026'
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: Multiple covers with balls
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2018'
...
---
_id: '6287'
abstract:
- lang: eng
  text: The main objects considered in the present work are simplicial and CW-complexes
    with vertices forming a random point cloud. In particular, we consider a Poisson
    point process in R^n and study Delaunay and Voronoi complexes of the first and
    higher orders and weighted Delaunay complexes obtained as sections of Delaunay
    complexes, as well as the Čech complex. Further, we examine theDelaunay complex
    of a Poisson point process on the sphere S^n, as well as of a uniform point cloud,
    which is equivalent to the convex hull, providing a connection to the theory of
    random polytopes. Each of the complexes in question can be endowed with a radius
    function, which maps its cells to the radii of appropriately chosen circumspheres,
    called the radius of the cell. Applying and developing discrete Morse theory for
    these functions, joining it together with probabilistic and sometimes analytic
    machinery, and developing several integral geometric tools, we aim at getting
    the distributions of circumradii of typical cells. For all considered complexes,
    we are able to generalize and obtain up to constants the distribution of radii
    of typical intervals of all types. In low dimensions the constants can be computed
    explicitly, thus providing the explicit expressions for the expected numbers of
    cells. In particular, it allows to find the expected density of simplices of every
    dimension for a Poisson point process in R^4, whereas the result for R^3 was known
    already in 1970's.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Anton
  full_name: Nikitenko, Anton
  id: 3E4FF1BA-F248-11E8-B48F-1D18A9856A87
  last_name: Nikitenko
  orcid: 0000-0002-0659-3201
citation:
  ama: Nikitenko A. Discrete Morse theory for random complexes . 2017. doi:<a href="https://doi.org/10.15479/AT:ISTA:th_873">10.15479/AT:ISTA:th_873</a>
  apa: Nikitenko, A. (2017). <i>Discrete Morse theory for random complexes </i>. Institute
    of Science and Technology Austria. <a href="https://doi.org/10.15479/AT:ISTA:th_873">https://doi.org/10.15479/AT:ISTA:th_873</a>
  chicago: Nikitenko, Anton. “Discrete Morse Theory for Random Complexes .” Institute
    of Science and Technology Austria, 2017. <a href="https://doi.org/10.15479/AT:ISTA:th_873">https://doi.org/10.15479/AT:ISTA:th_873</a>.
  ieee: A. Nikitenko, “Discrete Morse theory for random complexes ,” Institute of
    Science and Technology Austria, 2017.
  ista: Nikitenko A. 2017. Discrete Morse theory for random complexes . Institute
    of Science and Technology Austria.
  mla: Nikitenko, Anton. <i>Discrete Morse Theory for Random Complexes </i>. Institute
    of Science and Technology Austria, 2017, doi:<a href="https://doi.org/10.15479/AT:ISTA:th_873">10.15479/AT:ISTA:th_873</a>.
  short: A. Nikitenko, Discrete Morse Theory for Random Complexes , Institute of Science
    and Technology Austria, 2017.
date_created: 2019-04-09T15:04:32Z
date_published: 2017-10-27T00:00:00Z
date_updated: 2023-09-15T12:10:34Z
day: '27'
ddc:
- '514'
- '516'
- '519'
degree_awarded: PhD
department:
- _id: HeEd
doi: 10.15479/AT:ISTA:th_873
file:
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file_date_updated: 2020-07-14T12:47:26Z
has_accepted_license: '1'
language:
- iso: eng
month: '10'
oa: 1
oa_version: Published Version
page: '86'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
pubrep_id: '873'
related_material:
  record:
  - id: '718'
    relation: part_of_dissertation
    status: public
  - id: '5678'
    relation: part_of_dissertation
    status: public
  - id: '87'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: 'Discrete Morse theory for random complexes '
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: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2017'
...
---
_id: '1399'
abstract:
- lang: eng
  text: This thesis is concerned with the computation and approximation of intrinsic
    volumes. Given a smooth body M and a certain digital approximation of it, we develop
    algorithms to approximate various intrinsic volumes of M using only measurements
    taken from its digital approximations. The crucial idea behind our novel algorithms
    is to link the recent theory of persistent homology to the theory of intrinsic
    volumes via the Crofton formula from integral geometry and, in particular, via
    Euler characteristic computations. Our main contributions are a multigrid convergent
    digital algorithm to compute the first intrinsic volume of a solid body in R^n
    as well as an appropriate integration pipeline to approximate integral-geometric
    integrals defined over the Grassmannian manifold.
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Florian
  full_name: Pausinger, Florian
  id: 2A77D7A2-F248-11E8-B48F-1D18A9856A87
  last_name: Pausinger
  orcid: 0000-0002-8379-3768
citation:
  ama: Pausinger F. On the approximation of intrinsic volumes. 2015.
  apa: Pausinger, F. (2015). <i>On the approximation of intrinsic volumes</i>. Institute
    of Science and Technology Austria.
  chicago: Pausinger, Florian. “On the Approximation of Intrinsic Volumes.” Institute
    of Science and Technology Austria, 2015.
  ieee: F. Pausinger, “On the approximation of intrinsic volumes,” Institute of Science
    and Technology Austria, 2015.
  ista: Pausinger F. 2015. On the approximation of intrinsic volumes. Institute of
    Science and Technology Austria.
  mla: Pausinger, Florian. <i>On the Approximation of Intrinsic Volumes</i>. Institute
    of Science and Technology Austria, 2015.
  short: F. Pausinger, On the Approximation of Intrinsic Volumes, Institute of Science
    and Technology Austria, 2015.
date_created: 2018-12-11T11:51:48Z
date_published: 2015-06-01T00:00:00Z
date_updated: 2023-09-07T11:41:25Z
day: '01'
degree_awarded: PhD
department:
- _id: HeEd
language:
- iso: eng
month: '06'
oa_version: None
page: '144'
publication_identifier:
  issn:
  - 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
publist_id: '5808'
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  - id: '1792'
    relation: part_of_dissertation
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  - id: '2255'
    relation: part_of_dissertation
    status: public
status: public
supervisor:
- first_name: Herbert
  full_name: Edelsbrunner, Herbert
  id: 3FB178DA-F248-11E8-B48F-1D18A9856A87
  last_name: Edelsbrunner
  orcid: 0000-0002-9823-6833
title: On the approximation of intrinsic volumes
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2015'
...
