*Stars indicate student co-authors. New
papers, changes in publication status, and other additions are marked
for a few months. The square icons are direct
links to the most recent electronic
versions. If you'd like a hard copy of something, just
send me email.
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Minimum cuts and shortest homologous cycles
Written with
Erin Wolf Chambers
and
Amir Nayyeri*
Submitted to the 25th Annual Symposium on Computational Geometry (2009)
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Homology flows, cohomology cuts
Written with
Erin Wolf Chambers
and
Amir Nayyeri*
Submitted to the 41st ACM Symposium on Theory of Computing (2009)
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Computing the shortest essential cycle
Written with Pratik Worah*
Preprint, July 2008.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Testing contractibility in planar Rips complexes
Written with
Erin Wolf Chambers*
and
Pratik Worah*
Proceedings of the
24th Annual ACM Symposium on Computational Geometry, 251-259, 2008.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Walking your dog in the woods in polynomial time
Written with
Erin Wolf Chambers*,
Éric Colin de Verdière,
Sylvain Lazard,
Francis Lazarus, and
Shripad Thite
Proccedings of the
24th Annual ACM Symposium on Computational Geometry, 101-109, 2008.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Rips complexes of planar point sets
Written with
Erin Wolf Chambers*,
Vin de Silva,
and
Robert Ghrist
Preprint, December 2007.
ArXiv:0712.0395.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Empty-ellipse graphs
Written with
Xavier Goaoc
and
Olivier Devillers
Proceedings of the
19th Annual ACM-SIAM Symposium on Discrete Algorithms, 1249-1257, 2008.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Finding one tight cycle
Written with
Sergio Cabello,
Matt DeVos, and
Bojan Mohar
Proceedings of the
19th Annual ACM-SIAM Symposium on Discrete Algorithms, 527-531, 2008.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Necklaces, convolutions, and X+Y
Written with
David Bremner,
Timothy M. Chan,
Erik D. Demaine,
Ferran Hurtado,
John Iacono,
Stefan Langerman,
Ileana Streinu, and
Perouz Taslakian*
Proceedings of the 12th Annual European Symposium on Algorithms, 160-171, 2006.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Splitting (complicated) surfaces is hard
Written with
Erin Wolf Chambers*,
Éric Colin de
Verdière,
Francis Lazarus, and
Kim Whittlesey
Proceedings of the
22nd Annual ACM Symposium on Computational Geometry, 421-429, 2006.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Minimum-cost coverage of point sets by disks
Written with
Helmut Alt,
Esther M. Arkin,
Hervé Brönnimann,
Sándor P. Fekete,
Christian Knauer,
Jonathan Lenchner*,
Joseph S. B. Mitchell, and
Kim Whittlesey
Proceedings of the
22nd Annual ACM Symposium on Computational Geometry, 449-458, 2006.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Tightening non-simple paths and cycles on surfaces
Written with
Éric Colin de Verdière
Proceedings of the
17th Annual ACM-SIAM Symposium on Discrete Algorithms,
192-201, 2006.
|
 |
![[PDF]](pix/pdf.gif) |
Realizing partitions respecting full and
partial order information
Written with
Erik D. Demaine,
Danny Krizanc,
Henk Meijer,
Pat Morin,
Mark Overmars, and
Sue Whitesides
Journal of Discrete Algorithms 6:51-58, 2008.
(Special issue of invited papers from the
16th Australasian Workshop on Combinatorial Algorithms)
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Greedy optimal homotopy and homology generators
Written with
Kim Whittlesey
Proceedings of the
16th Annual ACM-SIAM
Symposium on Discrete Algorithms, 1038-1046, 2005.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Lower bounds for external algebraic decision
trees
Proceedings of the
16th Annual ACM-SIAM
Symposium on Discrete Algorithms, 755-761, 2005.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Efficient tradeoff schemes in data structures
for querying moving objects
Written with
Pankaj K. Agarwal,
Lars Arge, and
Hai Yu*
Proceedings of the
12th Annual European
Symposium on Algorithms, 4-15, 2004.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/pdf.gif) |
Automatic blocking scheme for structured meshing in 2d multiphase flow simulation
Written with
Damrong Guoy
Proceedings of the 13th Annual
International Meshing Roundtable, 121--132, 2004.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Spacetime meshing with adaptive refinement and coarsening
Written with
Reza Abedi*,
Shuo-Heng Chung*,
Yong Fan*,
Michael Garland,
Damrong Guoy,
Robert Haber,
John Sullivan,
Shripad Thite*, and
Yuan Zhou*.
Proceedings of the
20th Annual ACM Symposium on
Computational Geometry, 300-309, 2004.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
On the least median square problem
Written with
Sariel Har-Peled and
David Mount.
Proceedings of the
20th Annual ACM Symposium on
Computational Geometry, 273-279, 2004.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Separating point sets in polygonal environments
Written with
Erik D. Demaine,
Ferran Hurtado,
John Iacono,
Stefan Langerman,
Henk Meijer,
Mark Overmars,
and Sue Whitesides.
Proceedings of the
20th Annual ACM Symposium on
Computational Geometry, 10-16, 2004.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
On the complexity of halfspace volume queries
Written with
Erik D. Demaine and
Stefan Langerman.
Proceedings of the
15th Canadian Conference on
Computational Geometry, 159-160, 2003.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Output-sensitive algorithms for computing nearest-neighbor decision
boundaries
Written with
David Bremner,
Erik D. Demaine,
John Iacono,
Stefan Langerman,
Pat Morin,
and
Godfried Toussaint.
Proceedings of the 2003 Workshop on Algorithms and Data
Structures, 451-461, 2003.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Local polyhedra and geometric graphs
Computational Geometry: Theory and Applications 31(1-2):101-125, 2005.
(Special issue of invited papers from the
19th Annual ACM Symposium on Computational Geometry)
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Uniform samples of generic surfaces have nice Delaunay triangulations
Preprint, December 2002.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Capturing a convex object with three discs
Written with
Jean
Ponce,
Fred
Rothganger*, and
Shripad Thite*
Proceedings of the 2003 IEEE
International Conference on Robotics and Automation,
2242-2247, 2003.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Flipping cubical meshes
Written with
Marshall
Bern and
David Eppstein.
Engineering with Computers 18(3):173-187,
2002.
(Special issue of invited papers from the
10th
International Meshing Roundtable).
arXiv:cs.CG/0108020
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Flat-state connectivity of linkages under dihedral motions
Written with
Greg Aloupis*,
Erik D. Demaine,
Vida Dujmovic'*,
Stefan Langerman,
Henk Meijer,
Ileana Streinu,
Joseph O'Rourke,
Mark Overmars,
Michael Soss,
and
Godfried Toussaint.
Proceedings of the
13th Annual International Symposium on Algorithms and
Computation, 369-380, 2002.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Building spacetime meshes over arbitrary spatial domains
Written with
Damrong Guoy,
John Sullivan, and
Alper Üngör*.
Proceedings of the
11th
International Meshing Roundtable,
391-402, 2002.
arXiv:cs.CG/0206002
Submitted for journal publication.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Optimally cutting a surface into a disk
Written with
Sariel Har-Peled.
Discrete & Computational Geometry 31(1):37-59, 2004.
(Special issue of invited papers from the
18th Annual ACM Symposium on Computational Geometry)
arXiv:cs.CG/0207004
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Vertex-unfoldings of simplicial manifolds
Written with
Erik D. Demaine*,
David Eppstein,
George W. Hart,
and Joseph O'Rourke.
Discrete Geometry: In Honor of
W. Kuperberg's
60th Birthday
(András Bezdek,
editor), Marcel Dekker, 2003, pp. 215-228.
arXiv:cs.CG/0110054
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Preprocessing chains for fast dihedral
rotations is hard or even impossible
Written with
Michael A. Soss*
and
Mark Overmars.
Computational Geometry: Theory and Applications
26(3):235-246, 2003.
arXiv:cs.CG/0204042
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Algorithmic issues in modeling motion
by Pankaj K. Agarwal,
Leonidas J. Guibas,
and 19 others.
ACM Computing Surveys
34(4):550-572, 2002.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Dense point sets have sparse Delaunay triangulations
Discrete & Computational Geometry 33:83--115, 2005.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Arbitrarily large neighborly families of
congruent symmetric convex 3-polytopes
Written with Scott Kim.
Discrete Geometry: In Honor of
W. Kuperberg's
60th Birthday
(András Bezdek,
editor), Marcel-Dekker, 2003, pp. 267-278.
arXiv:math.CO/0106095
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Nice point sets can have nasty Delaunay triangulations
Discrete & Computational Geometry
30(1):109-132, 2003.
(Special issue of invited papers from the
17th
Annual ACM Symposium on Computational Geometry).
arXiv:cs.CG/0103017
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Flipturning polygons
Written with
Oswin Aichholzer,
Carmen Cortés,
Vida Dujmovic'*,
Erik D. Demaine*,
Henk Meijer,
Mark Overmars,
Belén Palop,
Suneeta Ramaswami,
and
Godfried Toussaint
Discrete & Computational Geometry
28:231-253, 2002.
arXiv:cs.CG/0008010
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Reconfiguring convex polygons
Written with
Oswin Aichholzer,
Erik D. Demaine*,
Ferran Hurtado,
Mark Overmars,
Michael A. Soss*, and
Godfried Toussaint.
Computational Geometry: Theory and Applications
20(1-2):85-95, 2001.
(Special issue of invited papers from the
12th
Annual Canadian Conference on Computational Geometry)
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Indexing moving points
Written with Pankaj K. Agarwal and
Lars Arge.
Journal of Computer and System Sciences
66:207-243, 2003
(Special issue of invited papers from the
19th ACM Symposium on Principles
of Database Systems).
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Finding longest arithmetic progressions
Manuscript, July 1999.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Finite-resolution hidden surface removal
Proceedings of the
11th Annual ACM-SIAM Symposium on
Discrete Algorithms, 901-909, 2000.
arXiv:cs.CG/9910017
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Kinetic collision detection for two simple polygons
Written with
Julien Basch*,
Leonidas J. Guibas,
John Hershberger, and
Li Zhang*.
Proceedings of the 10th Annual
ACM-SIAM Symposium on Discrete Algorithms, 102-111, 1999.
Computational Geometry: Theory and Applications 27:211-235, 2004.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Separation-sensitive collision detection for convex objects
Written with
Leonidas J. Guibas,
Jorge Stolfi, and
Li Zhang*.
Proceedings of the 10th Annual
ACM-SIAM Symposium on Discrete Algorithms, 327-336, 1999.
arXiv:cs.CG/9809035
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Raising roofs, crashing cycles, and playing pool:
Applications of a data structure for finding pairwise interactions
Written with David Eppstein.
Discrete & Computational Geometry
22(4):569-592, 1999.
(Special issue of invited papers from the
14th Annual ACM Symposium on Computational Geometry)
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Efficient searching with linear constraints
Written with Pankaj K. Agarwal,
Lars Arge,
Paolo G. Franciosa*,
and Jeffrey Scott Vitter.
Journal of Computer and System Sciences
61(2):192-216,
2000.
(Special issue of invited papers from the
17th ACM Symposium on Principles of Database Systems)
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Kinetic binary space partitions for intersecting segments and
disjoint triangles
Written with Pankaj K. Agarwal and
Leonidas J. Guibas.
Proceedings of the
9th Annual
ACM-SIAM Symposium on Discrete Algorithms, 107-116, 1998.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Geometric range searching and its relatives
Written with Pankaj K. Agarwal.
Advances in Discrete and Computational Geometry
(Bernard Chazelle,
Jacob E. Goodman, and
Richard Pollack, editors),
Contemporary Mathematics 223,
American Mathematical Society Press, 1999,
pp. 1-56.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Space-time tradeoffs for emptiness queries
SIAM
Journal on Computing
29(6):1968-1996, 2000.
Recent improvements!
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
New lower bounds for halfspace emptiness
Proceedings of the
37th Annual IEEE Symposium on Foundations of Computer Science,
472-481, 1996.
Merged into the journal version of "Space-time tradeoffs for emptiness queries".
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Lower Bounds for Fundamental Geometric Problems
Ph.D. dissertation,
University of California at Berkeley, July 1996.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
New lower bounds for convex hull problems in odd dimensions
SIAM Journal on Computing
28(4):1198-1214, 1999.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Sowing games
In
Games of No Chance
(Richard J. Nowakowski, editor),
Mathematical Sciences Research Institute Publications 29,
Cambridge University Press, 1996, pp. 287-297.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
New Toads and Frogs results
In
Games of No Chance
(Richard J. Nowakowski, editor),
Mathematical Sciences Research Institute Publications 29,
Cambridge University Press, 1996, pp. 299-310.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
On the relative complexities of some geometric problems
Proceedings of the
7th Canadian
Conference on Computational Geometry, 85-90, 1995.
Submitted for journal publication.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
New lower bounds for Hopcroft's problem
Discrete &
Computational Geometry
16(4):389-418, 1996.
(Special issue of invited papers from the
11th Annual ACM Symposium on Computational Geometry)
Recent improvements!
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Lower bounds for linear satisfiability problems
Chicago Journal of Theoretical Computer Science
1999(8), 1999.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Better lower bounds on detecting affine and spherical degeneracies
Written with Raimund Seidel.
Discrete &
Computational Geometry 13(1):41-57, 1995.
Erratum in
Discrete & Computational Geometry 18:239-240, 1997.
|
![[PS]](pix/ps.gif) |
![[PDF]](pix/pdf.gif) |
Iterated nearest neighbors and finding minimal polytopes
Written with David Eppstein.
Discrete &
Computational Geometry 11(3):321-350, 1994.
|
![[PS]](pix/nops.gif) |
![[PDF]](pix/nopdf.gif) |
New algorithms for minimum measure simplices and
one-dimensional weighted Voronoi diagrams
Written with David Eppstein.
U. C. Irvine Technical Report 92-55, June 1992.
|