From Sylvain.Pion at sophia.inria.fr Tue Nov 4 19:55:12 2003
From: Sylvain.Pion at sophia.inria.fr (Sylvain Pion)
Date: Mon Jan 9 13:41:12 2006
Subject: CGAL 3.0 Released, Computational Geometry Algorithms Library
Message-ID: <20031104195512.R1857@termite.inria.fr>
We are pleased to announce the release 3.0 of CGAL, the Computational Geometry
Algorithms Library. Version 3.0 differs from version 2.4 in licensing, in the
platforms that are supported and in functionality.
The license has been changed to either the LGPL (GNU Lesser General Public
License v2.1) or the QPL (Q Public License v1.0) depending on each package.
So CGAL remains free of use for you, if your usage meets the criteria of
these licenses, otherwise, a commercial license has to be purchased from
Geometry Factory (www.geometryfactory.com).
Major changes in this release include the following:
o Apollonius graph: the dual of the Voronoi diagram of a set of circles under
the Euclidean metric. The implementation is dynamic.
o Min_sphere_of_spheres_d: Algorithms to compute the smallest enclosing sphere
of a given set of spheres in d-dimensional space.
o Spatial Searching: Provides exact and approximate distance browsing in a set
of points in d-dimensional space (such as nearest neighbor searching).
o Largest_empty_iso_rectangle_2: Given a set of points P in the plane,
computes the largest empty iso-rectangle that are inside a given
iso-rectangle bounding box, and that do not contain any point of P.
o Interval_skip_list: A data strucure for finding all intervals in R that
contain a value, and for stabbing queries, that is for answering the
question whether a given value is contained in an interval or not.
o Existing packages have been improved in various area:
2D and 3D triangulations, Planar Maps, Arrangements...
o The CORE library (http://www.cs.nyu.edu/exact/core/) for exact computations
is now distributed as part of CGAL as well.
o We support the latest versions of the C++ compilers from GNU, Microsoft,
Intel, Sun, SGI.
o All demos are now using the portable Qt window toolkit.
See http://www.cgal.org/releases_frame.html for a complete list of changes.
The CGAL project is a collaborative effort to develop a robust,
easy-to-use, and efficient C++ software library of geometric data
structures and algorithms. The CGAL library contains:
o Basic geometric primitives such as points, vectors, lines, predicates
for testing things such as relative positions of points, and operations
such as intersections and distance calculation.
o A collection of standard data structures and geometric algorithms,
such as convex hull, (Delaunay, Regular, Constrained) triangulation, Voronoi
diagrams, planar map, arrangements, polyhedron, smallest enclosing sphere,
multidimensional query structures...
o Interfaces to other packages, e.g. for visualization, and I/O, and
other support facilities.
For further information and for downloading the library and its
documentation, please visit the CGAL web page: http://www.cgal.org/
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From jardine at uwo.ca Tue Nov 4 18:11:10 2003
From: jardine at uwo.ca (Rick Jardine)
Date: Mon Jan 9 13:41:12 2006
Subject: "Algebraic Topological Methods in Computer Science, II"
Message-ID: <3FA8320E.5060306@uwo.ca>
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Conference Announcement:
Algebraic Topological Methods in Computer Science, II
Department of Mathematics
University of Western Ontario
London, Ontario, Canada
July 16-20, 2004
This is the second installment of a conference series; the first was
held at Stanford University in the summer of 2001.
The main areas to be covered by this conference include computational
geometry and topology, networks and concurrency theory. The meeting
will consist of twenty invited lectures, with additional sessions for
shorter lectures.
The following mathematical scientists have been invited to speak:
Saugata Basu (Georgia Tech)
Marshall Bern (Xerox PARC)
Herbert Edelsbrunner (CS, Duke)
Robin Forman (Rice)
Eric Goubault (Commissariat a l'Energie Atomique, France)
Joel Hass (Math, UC Davis)
Maurice Herlihy (CS, Brown)
Kathryn Hess (Lausanne)
Michael Joswig (Berlin)
Reinhard Laubenbacher (Virginia Bioinformatics Institute)
Martin Raussen (Aalborg)
Vin de Silva (Stanford)
Michael Stillman (Cornell)
This conference has been funded by grants from the National Science
Foundation and the Fields Institute.
All conference announcements and information will be available at the
web page http://www.math.uwo.ca/~jardine/at-csII.html.
The organizers for this meeting are:
Gunnar Carlsson, gunnar@math.stanford.edu
Rick Jardine, jardine@uwo.ca
From scot at moosilauke.cs.dartmouth.edu Wed Nov 12 13:11:37 2003
From: scot at moosilauke.cs.dartmouth.edu (Scot Drysdale)
Date: Mon Jan 9 13:41:12 2006
Subject: Tenure-track positions at Dartmouth
Message-ID: <200311121811.hACIBb616865@moosilauke.cs.dartmouth.edu>
Please note that algorithms (including Computational Geometry) is an
area which we are targeting in these searches.
Scot Drysdale
===========================================
DARTMOUTH COLLEGE
Faculty Position in Computer Science
The Department of Computer Science seeks candidates for faculty positions
starting in September 2004. We anticipate several tenure-track openings
at the Assistant Professor level. Senior faculty appointments may also
be possible.
Candidates in programming languages/compilers, security, systems,
graphics, algorithms, robotics, and computational science are particularly
encouraged to apply. Strong candidates in all areas of computer science
will be seriously considered.
Persons interested should submit a curriculum vitae, a research statement,
and a teaching statement. Please ask at least four professionals to send
letters of reference, at least one of whom can comment on teaching. Full
consideration will be given to applications that arrive by December 1, 2003.
Please send application materials and general inquiries to:
Delia Mauceli
Computer Science Recruiting
Department of Computer Science
Dartmouth College
6211 Sudikoff Laboratory
Hanover, NH 03755-3510
Specific questions can be referred to Scot Drysdale, at
recruit@cs.dartmouth.edu.
Information on faculty and their research, facilities, and graduate students
is available at http://www.cs.dartmouth.edu. Our department is affiliated
with the Institute for Security Technology Studies, and further information
can be found at http://www.ists.dartmouth.edu.
Dartmouth is an equal opportunity/affirmative action employer and encourages
applications from women and members of minority groups.
-------------
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From thill at tomotherapy.com Wed Nov 12 08:59:37 2003
From: thill at tomotherapy.com (Ted Hill)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
Message-ID: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
I want to be able to calculate the area inside a closed many-sided
polygon.
Given an array of the (x,y) vertices that define the polygon, is there a
well-known algorithm that can calculate the enclosed area quickly?
Thanks,
Ted Hill
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From andreas.fabri at geometryfactory.com Wed Nov 12 23:27:12 2003
From: andreas.fabri at geometryfactory.com (Andreas Fabri)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
In-Reply-To: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
References: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
Message-ID: <3FB2B3C0.60203@geometryfactory.com>
Hi,
You might have a look at CGAL, the Computational Geometry Algorithm Library.
http://www.cgal.org/Manual/doc_html/basic_lib/Polygon_ref/Function_area_2.html#Cross_link_anchor_0
andreas
Ted Hill a ?crit:
> I want to be able to calculate the area inside a closed many-sided
> polygon.
>
>
>
> Given an array of the (x,y) vertices that define the polygon, is there
> a well-known algorithm that can calculate the enclosed area quickly?
>
>
>
> Thanks,
>
>
>
> Ted Hill
>
>
>
>
>
>
>
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From barequet at cs.technion.ac.il Thu Nov 13 00:07:59 2003
From: barequet at cs.technion.ac.il (Gill Barequet)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
Message-ID: <200311122207.hACM7xNU012260@csa.cs.technion.ac.il>
On Wed, 12 Nov 2003 08:59:37 "Ted Hill" wrote:
> I want to be able to calculate the area inside a closed many-sided polygon.
> Given an array of the (x,y) vertices that define the polygon, is there a
> well-known algorithm that can calculate the enclosed area quickly?
Use the well-known sailor's algorithm: Assume wlog that the polygon is above
the X axis. Project all the polygon's edges to the X axis, and sum up the
signed areas of all the induced trapezoids. (Set the sign of a trapezoid
acoording to whether or not the inducing oriented edge goes from left to right.)
(Theoretically you can compute the area in linear time also by triangulating
the polygon and summing up the areas of the triangles... 8-)
Gill
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From hans at tat.physik.uni-tuebingen.de Thu Nov 13 00:17:42 2003
From: hans at tat.physik.uni-tuebingen.de (Torsten Hans)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
In-Reply-To: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
Message-ID:
Hi,
a very elegant and fast (since it is linear) way to do this is
to use Green's theorem over the border of the closed polygon.
the polygon doesn't need to be convex.
Just as a reminder: Green's theorem reduces a surface integral
to a line integral over the border of the surface integral.
(sorry for my bad english).
here is a c code fragmet that calculates the area
and center.
num_vertices is the number of vertices of the polygon.
v2dx[] and v2dy[] are double arrays that store the x and y positions.
for easier computation the first vertex v2dx[0] and v2dy[0]
is stored in v2dx[n] and v2dy[n] again.
-------------------------------------------------------
double area = 0;
double center2dx = 0;
double center2dy = 0;
for (int i=0; i I want to be able to calculate the area inside a closed many-sided
> polygon.
>
> Given an array of the (x,y) vertices that define the polygon, is there a
> well-known algorithm that can calculate the enclosed area quickly?
>
> Thanks,
>
> Ted Hill
>
>
>
>
-------------
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From hans at tat.physik.uni-tuebingen.de Thu Nov 13 00:20:08 2003
From: hans at tat.physik.uni-tuebingen.de (Torsten Hans)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
In-Reply-To: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
Message-ID:
Hi again,
in my previous post I said I used Green's theorem.
This is not correct, i meant Stoke's theorem.
sorry for that.
Torsten Hans
On Wed, 12 Nov 2003, Ted Hill wrote:
> I want to be able to calculate the area inside a closed many-sided
> polygon.
>
> Given an array of the (x,y) vertices that define the polygon, is there a
> well-known algorithm that can calculate the enclosed area quickly?
>
> Thanks,
>
> Ted Hill
>
>
>
>
-------------
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From skoranne at tanner.com Wed Nov 12 14:55:17 2003
From: skoranne at tanner.com (Sandeep Koranne)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
Message-ID: <9F874F181B17D511A6BE00B0D0AB3303012FCE81@shelby.tanner.com>
Hi TEd,
Here is a simple method,
let us say the polygon is given by { (0,0), (10,0), (10,10), (0,10) }
Gven the array of [x,y] write then in 2 columns
X Y
--------
0 0
10 0
10 10
0 10
0 0
do cross multiplication as you march down the column and sum the results on
left side and right side
eg
0*0 + 10*10+10*10+0*0 = 200 on left column
0*10+ 0*10 +10*0 + 10*0 = 0 on right column
subtract the left column from right column = 0 - 200 = -200
divide this by 2 to get area = -100 (if you want absolute area use abs)
HTH
sandeep
btw: this can be programmed in 4way SIMD on Intel and others to run
"extremely fast"
-----Original Message-----
From: Ted Hill [mailto:thill@tomotherapy.com]
Sent: Wednesday, November 12, 2003 7:00 AM
To: compgeom-discuss@research.bell-labs.com
Subject: Algorithm for Area of a closed polygon.
I want to be able to calculate the area inside a closed many-sided polygon.
Given an array of the (x,y) vertices that define the polygon, is there a
well-known algorithm that can calculate the enclosed area quickly?
Thanks,
Ted Hill
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From Jeffrey_Danowitz at amat.com Thu Nov 13 11:44:36 2003
From: Jeffrey_Danowitz at amat.com (Jeffrey_Danowitz@amat.com)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
Message-ID:
Hi!
Perhaps this is equivalent to Gill's idea. Pick any vertex on the polygon.
No need to assume anything except that the array, p, of vertices is in
polygonal order, which it usually the case. From that point, build 2
vectors (p(b),p(b+1)), (p(b),p(b+2)) and take half the cross product
(signed area). Continue around taking vectors (p(b),p(b+i)) and
(p(b),p(b+i+1)) i=2,...n-1, summing the signed areas as you go along.
In the end take the absolute value -- and this is the area.
If you think about it, this is just Green's theorem in action. Clearly
this is a linear algorithm.
I hope my description is clear.
Yours,
Jeff
Gill Barequet
11/13/2003 12:07 AM
To: compgeom-discuss@research.bell-labs.com, thill@tomotherapy.com
cc:
Subject: Re: Algorithm for Area of a closed polygon.
On Wed, 12 Nov 2003 08:59:37 "Ted Hill" wrote:
> I want to be able to calculate the area inside a closed many-sided
polygon.
> Given an array of the (x,y) vertices that define the polygon, is there a
> well-known algorithm that can calculate the enclosed area quickly?
Use the well-known sailor's algorithm: Assume wlog that the polygon is
above
the X axis. Project all the polygon's edges to the X axis, and sum up the
signed areas of all the induced trapezoids. (Set the sign of a trapezoid
acoording to whether or not the inducing oriented edge goes from left to
right.)
(Theoretically you can compute the area in linear time also by
triangulating
the polygon and summing up the areas of the triangles... 8-)
Gill
-------------
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From dnave at psc.edu Wed Nov 12 21:23:16 2003
From: dnave at psc.edu (Demian M. Nave)
Date: Mon Jan 9 13:41:12 2006
Subject: Algorithm for Area of a closed polygon.
In-Reply-To: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
References: <1E2E66102E75104D8C740340EBCD98671BC279@tomoex.tomotherapy.com>
Message-ID:
Hi Ted,
> I want to be able to calculate the area inside a closed many-sided
> polygon.
As long as your polygon has no self-crossings or internal holes, this
algorithm is probably the simplest. It will return twice the _signed_ area
of your polygon:
Let 'vertices' be an array of N pairs (x,y), indexed from 0
Let 'area' = 0.0
for i = 0 to N-1, do
Let j = (i+1) mod N
Let area = area + vertices[i].x * vertices[j].y
Let area = area - vertices[i].y * vertices[j].x
end for
Return 'area'
If the vertices of your polygon are specified in counter-clockwise order
(i.e. by the right-hand rule), then the area will be positive. Otherwise,
the area will be negative, assuming the polygon has non-zero area to begin
with.
Hope this helps. Send another note to the mailing list if not. :-)
Cheers,
Demian
--
Demian M. Nave | dnave@psc.edu | Ph 412 268-4574
Pgh. Supercomputing Center | www.psc.edu/~dnave | Fx 412 268-8200
4400 Fifth Avenue | "When your work speaks for itself, don't
Pittsburgh, PA 15213 | interrupt." - Kanin
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From jjjjcrack at yahoo.com.cn Fri Nov 14 00:39:52 2003
From: jjjjcrack at yahoo.com.cn (=?gb2312?q?f=20f?=)
Date: Mon Jan 9 13:41:12 2006
Subject: Ask for help
Message-ID: <20031113163952.35575.qmail@web15202.mail.bjs.yahoo.com>
Dear Sirs:
who can tell me the process of contributing papers
to computer & Graphics. The email address, the
contacter, and so on.
Thank you very much!
Ding jian(jjjjcrack@yahoo.com.cn)
__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com
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From grima at us.es Thu Nov 20 16:53:52 2003
From: grima at us.es (Clara I. Grima)
Date: Mon Jan 9 13:41:12 2006
Subject: [Ewcg04] EWCG'04: SECOND ANNOUNCEMENT
In-Reply-To:
Message-ID: <000001c3af7e$8148d540$66b193c1@subdireccion>
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_______________________________________________
Ewcg04 mailing list
Ewcg04@listas.us.es
http://listas.us.es/mailman/listinfo/ewcg04
From pesasa at utu.fi Mon Nov 24 11:34:45 2003
From: pesasa at utu.fi (Petri Salmela)
Date: Mon Jan 9 13:41:12 2006
Subject: ICALP'04 - Call for Papers
Message-ID:
Printable pdf-version at:
http://www.math.utu.fi/icalp04/icalp-call.pdf
___________________________________________________________________
CALL FOR PAPERS - ICALP'04
31st International Colloquium on
Automata, Languages and Programming
July 12-16, 2004, Turku, Finland
http://www.math.utu.fi/icalp04/
___________________________________________________________________
The 31st International Colloquium on Automata, Languages and
Programming sponsored by the European Association of Theoretical
Computer Science will take place in Turku, on July 12-16, 2004.
It is organised at Turku University by the Department of
Mathematics and Turku Centre for Computer Science. ICALP04 is
colocated with the 19th International Conference on Logic in
Computer Science (LICS04).
Papers presenting original research on all aspects of theoretical
computer science are sought. Typical but not exclusive topics
of interest are:
Track A:
* Algorithmic aspects of parallel and distributed computing
* Algorithms and data structures
* Algorithms and models for large networks
* Algorithms for computationally hard problems
* Automata theory and formal languages
* Bioinformatics
* Computational complexity
* Combinatorics and structures in Computer Science
* Cryptography
* Machine learning
* Molecular computing, neural and evolutionary algorithms
* Proof complexity
* Quantum computing
Track B:
* Algebraic and categorical models
* Applications of automata in logic
* Concurrency, mobility and distributed systems
* Databases, semi-structured data and finite model theory
* Logics and their applications
* Principles of programming languages
* Program logics, formal methods and model checking
* Security analysis and verification
* Semantics of programming languages
* Specification, refinement and verification
* Type systems and typed calculi
SUBMISSIONS:
************
Authors are invited to submit a paper of no more than 12 pages in
LNCS-style, presenting original research on the theory of computer
science. Submissions should indicate which track the paper is
submitted to. No simultaneous submission to other conferences with
published proceedings is allowed. Accepted papers will be
published in the Lecture Notes in Computer Science by Springer.
IMPORTANT DATES:
****************
Workshop proposals: November 30, 2003
Submissions: February 8, 2004
Notification: March 31, 2004
Final version: April 27, 2004
CONFERENCE CHAIR:
*****************
Juhani Karhum?ki
Department of Mathematics and
Turku Centre for Computer Science
University of Turku
FIN-20014 Turku, Finland
email: karhumak@cs.utu.fi
INVITED SPEAKERS:
*****************
Joint ICALP-LICS:
R. Harper (Carnegie Mellon)
A. Razborov (Princeton & Moscow)
M. Yannakakis (Stanford)
ICALP:
P. Flajolet (INRIA)
M. Henzinger (Google)
M. Hofmann (Munich)
W. Rytter (Warsaw & NJIT)
PROGRAM COMMITTEE:
******************
Track A
A. Atserias, Barcelona (ES)
G. Brodal, Aarhus (DK)
J. Cassaigne, Marseille (FR)
J. D?az, Barcelona (ES), chair
R. Fleischer, Hong Kong (HK)
H. Gabow, Boulder (US)
L. Goldberg, Warwick (UK)
J. Hromkovic, Aachen (DE)
G. Italiano, Roma (IT)
T. Jiang, Riverside (US)
C. Kaklamanis, Patras (GR)
J. Kari, Turku (FI)
C. Moore, Santa Fe (US)
P. Pudlak, Prague (CZ)
P. Raghavan, Verity, Stanford (US)
M. Santha, Paris (FR)
B. Voecking, Dortmund (DE)
G. Woeginger, Twente (NL)
M. Yung, Columbia U. (US)
Track B
R.-J. Back, Turku (FI)
P.-L. Curien, Paris (FR)
A. Gordon, Microsoft, Cambridge (UK)
S. Hayashi, Kobe (JP)
T. Henzinger, Berkeley (US)
M. Hofmann, Munich (DE)
B. Jacobs, Nijmegen (NL)
E. Moggi, Genova (IT)
J. Parrow, Uppsala (SE)
C. Palamidessi, University Park, Penn. (US)
B. Pierce, Philadelphia (US)
A. Rabinovich, Tel Aviv (IL)
D. Sannella, Edinburg (UK), chair
W. Thomas, Aachen (DE)
I. Walukiewicz, Bordeaux (FR)
ORGANIZING COMMITTEE:
*********************
J. Karhum?ki, Conference Chair
T. J?rvi, Co-chair (ICALP)
L. Hella, Co-chair (LICS)
V. Halava
M. Hirvensalo
I. Petre
P. Sibelius
T. Knuutila
CONTACT ADDRESSES:
****************
For further information see:
http://www.math.utu.fi/icalp04/
or contact:
icalp04@cs.utu.fi or karhumak@cs.utu.fi
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From marina at cpsc.ucalgary.ca Tue Nov 25 17:45:32 2003
From: marina at cpsc.ucalgary.ca (Marina Gavrilova)
Date: Mon Jan 9 13:41:12 2006
Subject: CFP CGA'04
Message-ID: <000501c3b3b6$9900eba0$0300a8c0@delphi>
Dear Colleagues,
Please find attached CFP for CGA'04. We apologize in advance for
possible multiple listings.
CALL FOR PAPERS
============================================================
International Workshop on
Computational Geometry and Applications CGA'04
in conjunction with
The 2004 International Conference on Computational Science
and its Applications (ICCSA 2003)
http://iccsa2004.unipg.it/
May 14, 2004 - May 17, 2004
Perugia, Italy
Workshop Web Site:
http://pages.cpsc.ucalgary.ca/~marina/Newweb/session.htm
============================================================
Important Dates
---------------
January 15, 2004: Deadline for paper submission.
February 10, 2004: Notification of acceptance.
February 15, 2004: Camera Ready Papers and Pre-registration.
May 14 - 17, 2004: ICCSA 2003 Conference in Montreal, Canada.
Workshop Description
--------------------
The Workshop, held for the fourth year in a row in conjunction with the
International Conference on Computational Science and Its Applications,
is intended as an international forum for researchers in all areas of
computational geometry. Submissions of papers presenting a high-quality
original research are invited to one of the two Workshop tracks:
- theoretical computational geometry
- implementation issues and applied computational geometry.
Topics of interest:
-----------------------
- Algorithmic methods in geometry
- Animation of geometric algorithms
- Lower bounds and algorithm complexity
- Solid modeling
- Geographic information systems
- Computational methodology
- Computer graphics and image processing
- Illumination problems
- Visibility graphs
- Space Partitioning
- Data structures (including Voronoi Diagrams and Delaunay
triangulations)
- Geometric computations in parallel and distributed environments
- Mesh generation
- Interpolation and surface reconstruction
- Spatial and terrain analysis
- Computer graphics and image processing
- Computational methods in manufacturing
- Applications in molecular biology, granular mechanics,
computational physics, oceanography
- Exact computations
- Robotics
- Path planning
- Algorithm Implementation
- CAD/CAM
Submissions in other related areas will also be considered.
The design and implementation of geometric algorithms in parallel and
distributed environments, exact computations, and applications in
mechanics, physics and biology, are of special interest.
Proceedings
-------------
Proceedings of the Workshop will be published in the Springer-Verlag
Lecture Notes in Computer Science (LNCS) series. The proceedings will
also be available separately for purchase from Springer-Verlag
(proceedings of the previous Workshops on Computational Geometry and
Applications appeared in LNCS vol. 2073, vol. 2329-2331).
Papers from the Workshop may be invited to special issues of
International Journal of Computational Geometry and Applications,
Journal of CAD/CAM, Journal of Computational Methods in Sciences and
Engineering (JCMSE) and the Journal of Supercomputing (pending
agreement).
Best Student Paper Award and Travel Grant
------------------------------------------
This year, a best student paper will be selected for a Best Student
Paper Award. This award will be available exclusively to CGA'04
participants. A paper is eligible if at least one of its authors is a
full or part-time student at the time of submission.
Conference fees
----------------
For all details with respect to the conference fees please consult the
ICCSA 2004 web page.
Special discounts for students and
participants from some academia/research institutions are available. For
more information, please visit the Workshop web site.
Submission
-----------
We invite you to submit a draft of the paper of up to 10 pages (Letter
or A4) paper. Please include a cover page (in ascii format) which lists
the following:
- Title of the paper
- List of authors
- name, affiliation, address and e-mail address of each author
- name of the contact author
- preferred track (theoretical or applied track)
- a maximum of 5 keywords
- intent to be considered for the Best Student Paper Award (exclusively
for CGA'03 participants)
- intent to apply for Travel Grant (available for all ICCSA'03
participants)
The submission must be camera-ready and formatted according to the rules
of LNCS. Electronic submissions in PS, PDF, or LaTex (please also submit
all .eps, .dvi, and .ps files). MS Word submissions will also be
accepted.
Please submit your paper directly to e-mall address:
marina@cpsc.ucalgary.ca
Indicate in the header of the message "CGA'03 submission".
Organizing Committee
Conference Chairs:
Vipin Kumar (Army High Performance Computing Center, USA and University
of Minessota, USA) Honorary Chair
Osvaldo Gervasi (University of Perugia, Italy)
Marina Gavrilova (University of Calgary, Canada) Conference Co-Chair
CGA'04 Program Committee (still being formed)
Sergei Bespamyatnikh (Duke University, USA)
Tamal Dey (Ohio State University, USA)
Frank Dehne (Carleton University, Canada)
Ovidiu Daescu (University of Texas at Dallas, USA)
Christopher Gold (Hong Kong Polytechnic University)
Deok-Soo Kim (Hanyang University, Korea)
Andres Iglesias (University de Cantabria, Spain)
Kokichi Sugihara (University of Tokyo, Japan)
Vaclav Skala (University of West Bohemia, Czech Republic)
Stephen Wismath (University of Lethbridge, Canada)
J. A. Rod Blais (University of Calgary, Canada)
Marian Bubak (AGH, Poland)
Toni Cortes (Universidad de Catalunya, Barcelona, Spain)
Brian J. d'Auriol (University of Texas at El Paso, USA)
Ivan Dimov (Bulgarian Academy of Sciences, Bulgaria)
Matthew F. Dixon (Heuchera Technologies, UK)
Geoffrey Fox (Indiana University, USA)
Marina L. Gavrilova (University of Calgary, Canada)
Benjoe A. Juliano (California State University at Chico, USA)
Vipin Kumar (University of Minnesota, USA)
Antonio Lagana (Universit? Degli Studi di Perugia, Italy)
Renee S. Renner (California State University at Chico, USA)
Koichi Wada (University of Tsukuba, Japan)
Roy Williams (California Institute of Technology, USA)
Osman Yasar (SUNY at Brockport, USA)
Zahari Zlatev (Danish Environmental Research Institute, Denmark)
CGA'01, CGA'02 and CGA'03 profiles
To view electronic proceedings of the CGA, follow the link to LNCS web
site: http://turing.zblmath.fiz-karlsruhe.de/cs/www_lncs.1.html.
Invited speaker for CGA'01: Kokichi Sugihara, University of Tokyo, Japan
Invited speakers for CGA'02:
Mark Overmars, Utrecht University
Contributed Presentation: Pieter Huybers, the Netherlands
Invited speakers for CGA'03:
Chee Yap, New York University, USA
Godfried Toussaint, McGill University, Canada
List of papers appeared at CGA'01, CGA'02 and CGA'03 can be found on
Workshop web site as well as in LNCS series.
Selected papers from the previous workshops appeared in the special
issue of the International Journal of Computational Geometry and
Applcations (IJCGA), Volume 14, No 4, August 2003.
Please direct any questions to:
Marina L. Gavrilova
CGA'04 Chair
ICCSA'04 Co-Chair
Department of Computer Science,
University of Calgary,
2500 University Drive,
Calgary, Alberta, Canada, T2N1N4
Telephone: (403) 241-6315
Fax: (403) 284-4707
E-mail: marina@cpsc.ucalgary.ca
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From borisdev at yahoo.com Sun Nov 30 18:51:38 2003
From: borisdev at yahoo.com (Boris Dev)
Date: Mon Jan 9 13:41:12 2006
Subject: Relative Distance Cartogram algorithm question
In-Reply-To: <200312010226.hB12Q0Jl061479@grubby.research.bell-labs.com>
Message-ID: <20031201025138.17278.qmail@web60310.mail.yahoo.com>
I hope this is a comp geom problem:
If we have a distance matix can we put points on a 2
diminsional x, y coordinate grid so that they are
postioned relative to one another according to the
distance matrix elements.
- what if distance was defined in some non-euclidian
terms based on say correlation coeffients between
composite units of an aggregate (say as a function of
USA states'
comovements). In this case all restrictions based on
data might not be met with 2 dim coordinate plane. So
will
3dimensions suffice?
Is there an algorithm out there?
Any advice?
Ultimately, I want to make a graph/cartogram based on
different relative measures of distance.
Thanks much for all your time.
borisdev@yahoo.com
-------------
The compgeom mailing lists: see
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or send mail to compgeom-request@research.bell-labs.com with the line:
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Now archived at http://www.uiuc.edu/~sariel/CG/compgeom/maillist.html.
From akin.babayigit at yale.edu Wed Nov 26 19:28:18 2003
From: akin.babayigit at yale.edu (Akin Babayigit)
Date: Mon Jan 9 13:41:12 2006
Subject: Question about matrix representations of certain points
Message-ID: <1069892898.3fc545224a81e@www.mail.yale.edu>
Hi All,
I have a question that I have been dealing with and I thought I could
get some help here. It is as follows:
I have n points in the plane and I know all of their x-y coordinates.
Each point is the center of a circle with radius 'r'. For simplicity
let me continue by considering only three points n1,n2,n3 (Although
eventually I would like to work with an arbitrary number of points).
n1's coordinates are (x1,y1), n2's are (x2,y2) and n3's are (x3,y3).
These points are the centers of three circles C1,C2,C3. Let us assume
also that the intersection of these circles are non-empty.
What I would like to be able to do is figure out the coordinates of a
point (x,y) such that I can write x = [h1 h2 h3]*[x1 x2 x3]' and
y = [k1 k2 k3]*[y1 y2 y3]'
such that:
1) (x,y) is either in the intersection C1,C2,C3 or in the smallest
circle containing the convex hull if points n1,n2,n3
2) AND h1+h2+h3 = 1 and k1+k2+k3=1. i.e.: eventually i will have n
of these points (points with locations x,y) and the I want the matrices
K and H to be stochastic.
Any thoughts would be greatly appreciated.
Thank you for your time in advance,
Akin Babayigit
-------------
The compgeom mailing lists: see
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or send mail to compgeom-request@research.bell-labs.com with the line:
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Now archived at http://www.uiuc.edu/~sariel/CG/compgeom/maillist.html.