Proceedings of International Conferences
[110]
Tetsuo Asano, Taisuke Izumi, Masashi Kiyomi, Matsuo Konagaya, Hirotaka Ono,
Yota Otachi, Pascal Schweitzer, Jun Tarui, Ryuhei Uehara: "
Depth-First Search Using O(n) Bits," ISAAC 2014: 553-564.
[109] Tetsuo Asano, David G. Kirkpatrick, Kotaro Nakagawa, Osamu Watanabe:
"
O(√n)-Space and Polynomial-Time Algorithm for Planar Directed Graph Reachability,"
MFCS (2) 2014: 45-56.
[108] Tetsuo Asano, Amr Elmasry, and
Jyrki Katajainen, "Priority Queues and Sorting for
Read-Only Data," TAMC 2013: 32-41.
[107] T. Asano, S. Bereg, "A New Framework for Connected Components Labeling of
Binary Images," Proc. of the 15th International Workshop on
Combinatorial Image Analysis, pp.90-102, Austin, USA, November,
2012.
[106] T. Asano, S.
Bereg, L. Buzer, "Small Work Space Algorithms
for Some Basic Problems on Binary Images," Proc. of the 15th
International Workshop on Combinatorial Image Analysis, pp.103-114, Austin, USA,
November, 2012.
[105] Tetsuo Asano, Kevin Buchin, Maike Buchin, Matias Korman, Wolfgang Mulzer,
Gunter Rote, Andre Schulz "
Memory-Constrained Algorithms for Simple Polygons,
Proc. European Workshop on Computational Geometry, 2012.
[104] Tetsuo Asano and
Benjamin Doerr, ``Memory-Constrained
Algorithms for Shortest Path Problem,'' Proc. Canadian Conference on Computational Geometry,
Toronto, pp:135-138, 2011.
[103] Tetsuo Asano. ``Nearest
Larger Neighbors Problem and Memory-Constrained Algorithms,'' Abstract of International Workshop on
Combinatorial Algorithms, University of Victoria, June 20-22, 2011 (Plenary
Talk).
[102] Tetsuo Asano, ``Designing
Algorithms with Limited Work Space ,'' Proc. 8th Annual Conference on Theory and Applications of Models of
Computation (Invited Talk), Lecture Notes in Computer Science 6648, edited by
M. Ogihara and J. Tarui, p.1, Chofu, Tokyo, May 23-25, 2011.
[101] Tetsuo Asano and Matsuo Konagaya,``Zero-space Data structure for farthest-point Voronoi diagram,''Abstract of the 4th Annual Meeting of Asian
Association for Algorithms and Computation, p.44, HsinChu, Taiwan, April, 2011.
[100] Tetsuo Asano, ``Resource-Constrained
Algorithms: Space-Time Tradeoffs,''
to appear in Proc. WAAC 2010, Korea-Japan Workshop on Algorithms and
Computation, Kanazawa, pp. 190-201, July, 2010.
[99] Tetsuo Asano, Jesper Jansson, Kunihiko Sadakane, Ryuhei Uehara, and
Gabriel Valiente, ``Faster
Computation of the Robinson-Foulds Distance between Phylogenetic Networks,'' to appear in Proc. 21st Combinatorial
Pattern Matching, 2010.
[98] T. Asano, ``Do We Need a
Stack to Erase a Component in a Binary Image?,'' Fifth International Conference on FUN WITH
ALGORITHMS,pp.16-27, 2010.
[97] T. Asano, E. D. Demaine, M. L. Demaine, and R. Uehara, ``Kaboozle is NP-complete, even in a Strip Form,'' Fifth International Conference on FUN WITH
ALGORITHMS, pp. 28-36, 2010.
[96] T. Asano, W. Mulzer, and Y. Wang, ``Constant-Work-Space Algorithm for a Shortest Path in a
Simple Polygon,'' (Invited
talk) Proc. 4th International Workshop on Algorithms and Computation, WALCOM,
Dhaka, Bangladesh, pp.9-20, February 2010 (Lecture Notes of Computer Science,
LNCS 5942, Springer)..
[95] Tetsuo Asano, Jesper Jansson, Kunihiko Sadakane,
Ryuhei Uehara, Gabriel Valiente: Faster Computation
of the Robinson-Foulds Distance between Phylogenetic Networks.
CPM 2010, pp:190-201, 2009
[94] Tetsuo
Asano and Guenter Rote:
“Constant
Working-Space Algorithms for Geometric Problems,” Proc.
Canadian Conference on Computational Geometry, pp.87-90, Vancouver, 2009.
[93] Tetsuo Asano:
Constant-Working-Space Algorithms: How Fast Can We Solve Problems without Using
Any Extra Array?. ISAAC 2008: p.1,
Dec. 2008.
[92] T. Asano, ``Constant-Working-Space Algorithms for Image
Processing,'' ETVC08: Emerging Trends and Challenges in Visual
Computing,Ecole Polytechnique (
[91] T. Asano, ``Constant-Working-Space Algorithms,’’ Proc. Kyoto RIMS International Workshop on Computational Geometry
and Discrete Mathematics, October, 2008.
[90] T. Asano, ``Constant Working Space Algorithms with
Applications,'' Abstracts of 5th International Conference of Applied
Mathematics and Computing,'' p.I-47,
[89] T.Asano, “Constant-Working Space Algorithm
for Image Processing,”
Proc. of the First AAAC Annual meeting,
[88] Bishal Prasad, Arijit Bishnu, and
Tetsuo Asano: “Linear Boundary and Corner detection using limited number of
sensor rows, “ Proc. IWCIA
(Int. Workshop on Combinatorial Image Analysis) 2008, pp.250-261,
[87] T. Asano, " Constant-Working-Space
Image Scan with a Given Angle," Proc. 24th European
Workshop on Computational Geometry, March 18-20, pp. 165-168, 2008,
[86] T. Asano, "Online Uniformity of Integer Points on a Line,"
Proc. 24th European Workshop on Computational Geometry, March 18-20, pp.
99-102, 2008,
[85] Boris Aronov, Tetsuo Asano and Stefan
Funke, “Optimal Triangulation with Steiner Points,” Proc. ISAAC 2007,
[84] Tetsuo Asano, Shinnya Bitou, Mitsuo
Motoki and Nobuaki Usui, “In-Place Algorithm for Image Rotation,” Proc. ISAAC 2007,
[83] T. Asano: “Dissimilarity Preserving Embedding of Objects on the Plane,” Invited Talk at International Xu Guangqi Conference, Shanghai, Oct. 14-19, 2007.
[82] T. Asano and S. Teramoto,
“On-line uniformity of points”, Book of Abstracts for 8th Hellenic-European Conference
on Computer Mathematics and its Applications, pp. 21-22,
[81] T. Asano, P. Bose, P. Carmi, A. Maheshwari, C. Shu, M. Smid, and S. Wuhrer, “Linear-Space Algorithms for Distance Preserving Embedding”, Canadian Conference on Computational Geometry, pp.185-188, August, 2007.
[80] T. Asano,
[79] T. Asano, J. Matousek, and T. Tokuyama: “Zone Diagram: Existence, Uniqueness and Algorithmic Challenge,” SIAM-ACM Symposium on Discrete Algorithms, pp.756-765, January 2007.
[78] H.K. Ahn, H. Alt, T. Asano, S.W. Bae, P. Brass, O. Cheon, C. Knauer, H.S. Na, C.S. Shin, A. Wolff: ``Constructing Optimal Highways ,'' in Proc. CATS, pp.7-14, January 2007.
[77] X. Liang and, A. Bishnu, and
T. Asano, “Fingerprint Matching Using Minutia Polygons,” Proc. ICPR: 18th Intl. Conf. on Pattern
Recognition,
[76] X. Liang, T. Asano, and H. Zhang, “A
Combined Radial Basis Function Model for Fingerprint Distortion,” Proc. ICIAR: Intel. Cnf.
on Image Analysis and
[75] T. Asano, N. Katoh,
H. Tamaki, T. Tokuyama, “Angular Voronoi
Diagram with Applications,” Proc. International Symposium on Voronoi
Diagram in Science and Engineering, July,
[74] T. Asano, “Aspect-ratio
Voronoi Diagram with Applications,” Proc. International Symposium on Voronoi
Diagram in Science and Engineering, July,
[73] X. Liang, A. Bishnu, and T.
Asano, „Distorted Fingerprint Indexing Using Minutia Detail and
Delaunay Triangle,” Proc.
International Symposium on Voronoi Diagram in Science
and Engineering, July,
[72] T. Asano and D. Kirkpatrick, “Distance Trisector Curves in Regular Convex Distance Metrics, “ Proc. International Symposium on Voronoi Diagram in Science and Engineering, July, Banff, Canada, pp.8-17, 2006.
[71] T. Asano, J. Matousek, and
T. Tokuyama: “The Distance Trisector Curve,” ACM Symposium on Computing Theory,
[70]T. Asano, F. Rossell\'o, G. Valiente, “Template Matrices for Perfect Phylogeny Haplotyping and Site Consistency,” International Conference on Research in Computational Molecular Biology, 2006.
[69] T.Asano: "Computational Geometric and Combinatorial Approaches to Digital Halftoning," Computing: The Australasian Theory Symposium, January 16-19, 2006.
[68] T.Asano, S. Choe, S. Hashima, Y. Kikuchi, and
S.-C. Sung "Distributing Distinct Integers Uniformly over a
Square Matrix with Application to Digital Halftoning,"
Invited Talk at 7th Hellenic European Conference on Computer Mathematics and
its Applications,
[67]Xuefeng Liang, Kazunori Kotani and Tetsuo Asano: "Automatically Choosing Appropriately-Sized Structuring Elements to Eliminate Useless Components in Fingerprint Image," Proc. Visual Communications and Image Processing 2005, July, Beijing, edited by Shipeng Li, Fernando Pereira, Heung-Yeung Shum, Andrew G. Tescher, Proc. Of SPIE Vol.5960, pp. 284-293, 2005.
[66] T. Asano: "Computational Geometric and Combinatorial Approaches to
Digital Halftoning," Prenary Talk at International Conference on Computational Science
and Its Applications,
[65] S. Teramoto, T. Asano, B. Doerr, and N. Katoh "Inserting Points
Uniformly at Every Instance," Proc. 2005 Korea Japan Joint
Workshop on Algorithms and Computation, pp.3-9, 2005,
[64] E. Chiba, T. Asano, T. Miura, N. Katoh, and I. Mitsuka "Modeling of Transportation Systems Using Crash Probability," Proc. 2005 Korea Japan Joint Workshop on Algorithms and Computation, pp.142-149, 2005, Seoul, Korea.
[63] Boris Aronov, Tetsuo Asano, Yosuke Kikuchi, Subhas C. Nandy, Shinji Sasahara, and Takeaki Uno "A Generalization of Magic Squares with Applications to Digital Halftoning," Proc. of 15th International Symposium on Algorithms and Computation, ISAAC 2004, Hong Kong, China, December 2004, also in Lecture Notes in Computer Science LNCS 3341, edited by R. Fleischer and G. Trippen, "Algorithms and Computation," pp.89-100, 2004.
[62] Boris Aronov, Tetsuo Asano, Naoki Katoh, Kurt Mehlhorn, and Takeshi Tokuyama: "Polyline Fitting of Planar Points Under Min-sum Criteria," Proc. of 15th International Symposium on Algorithms and Computation, ISAAC 2004, Hong Kong, China, December 2004, also in Lecture Notes in Computer Science LNCS 3341, edited by R. Fleischer and G. Trippen, "Algorithms and Computation," pp.77-88, 2004.
[61] Xuefeng Liang, Arijit Bishnu, and Tetsuo Asano "A Near-Linear Time Algorithm for Binarization of Fingerprint Images Using Distance Transform," Proc. 10th International Workshop, IWCIA 2004, December, Auckland, Lecture Notes in Computer Science LNCS 3322, edited by R. Klette and J. Zunic, "Combinatorial Image Analysis," pp.197-208, 2004.
[60]T. Asano and T. Tokuyama "Drawing Equally-Spaced Curves between Two Points", Abstracts of 14th Annual Workshop on Computational Geometry with a Focus on Open Problems, pp.24-25, MIT, Cambridge Massachusetts, USA, November 19-20, 2004.
[59] Sachio Teramoto and T. Asano "Fast Implementation of Laguerre Voronoi Diagram with Hardware Assitance", Proc. International Symposium on Voronoi Diagrams in Science and Engineering, pp. 165-171, Tokyo, Japan, September, 2004.
[58] Xuefeng Liang and T. Asano "A Fast Denoising Method for Binary Fingerprint Image ", Proc. IASTED Conference on Visualization, Imaging, and Image Processing, Paper No. 452-168, pp. 309-313, Marbella, Spain, September, 2004.
[57] T.
Asano, Naoki Katoh, Hisao
Tamaki, and Takeshi Tokuyama "On Geometric Structure of Global Roundings for Graphs
and Range Spaces ", Proc. of the Scandinavian
Workshop on Algorithm Theory (SWAT 04) , pp. 455-467,
[56] T. Asano, P. Brass, S. Sasahara "Disc Covering Problem with Application to Digital Halftoning", Proc. of the Workshop on Computational Geometry and Applications (CGA 04) as a part of International Conference on Computational Science and Its Applications -- ICCSA 2004, Proceedings, Part III, pp.11-21, Assisi, Italy, May, 2004. Lecture Notes in Computer Science, LNCS 3045, part III, pp. 11-21, edited by A. Lagana, M.L. Gavrilova, V. Kumar, Y. Mun, C.J.K. Tan, O. Gervasi.
[55] S. Sasahara, T. Asano, "A new halftone technique to eliminate ambiguous pixels for stable printing", Proc Electronic Imaging Science and Technology, Color Imaging IX: Processing, Hardcopy, and Applications, pp.490-497. January 2004.
[54] T. Asano, "Algorithmic Approaches to Digital Halftoning," Abstracts for the 15th Canadian Conference on Computational Geometry, pp.72. August 2003.
[53] T. Asano, D. Kirkpatrick, C. Yap, "Minimizing the Endpoint Trace Length of Rod Motions amidst Polygonal Obstacles is NP-hard" Abstracts for the 15th Canadian Conference on Computational Geometry, pp.10-13. August 2003.
[52] T.
Asano, E.Chiba, "A New Approach to Transportation Scheduling
Problem Based on Network Flow Theory" Proc. 7th Japan Korea
Joint Workshop on Algorithms and Computation, pp.228-236,
[51] T.Shimamoto T. Asano, "Arranging Fewest Possible Probes to Detect a
Hidden Object with Industrial Application" Proc. 7th Japan
Korea Joint Workshop on Algorithms and Computation, pp.105-115,
[50] S.Sasahara T. Asano, "Adaptive Cluster Arrangement for Cluster-dot Halftoning Using Bubble Packing Method," Proc. 7th Japan Korea Joint Workshop on
Algorithms and Computation, pp.87-93,
[49] T. Asano, R. Klette, C. Ronse (Eds.), "Geometry, Morphology, and Computational Imaging," Proc. 11th International Workshop on Theoretical Foundations of Computer Vision, Dagstuhl Castle, Germany, April 7-12, 2002, Lecture Notes on Computer Science 2616, 2003.
[48] T. Asano,
[47] T. Asano, Y.
Kawamura, R. Klette, K. Obokata,
"Minimum-Length
Polygons in Approximation Sausages," Proc.
the 4th International Workshop on Visual Form, IWVF4, pp.103-112, May 2001.
[46] T. Asano and T.
Tokuyama, "How to Color a Checkerboard with a Given Distribution ---
Matrix Rounding Achieving Low 2x2-Discrepancy," Proc. Int. Symp. on
Algorithms and Computation, pp. 636-648, 2001.
[45] T. Asano, Y.
Kawamura, R. Klette, and K. Obokata:
"A New
Approximation Scheme for Digital Objects and Curve Length Estimations,"
Proc. Image and Vision Computing New Zealand 2000 (IVCNZ'00), pp.26-31,
[44]T.
Asano, K. Obokata, and T. Tokuyama: "On Detecting
Digital Line Components in a Binary Image," Proc. 5th Japan
Korea Joint Workshop on Algorithms and Computation, pp.144-151,
[43]T. Asano, T. Matsui, and T. Tokuyama: "On the Complexities of the Optimal Rounding
Problems of Sequences and Matrices," Proc. 7th Scandinavian
Workshop on Algorithm Theory, pp.476-489,
[42] S.C. Nandy, T. Asano, and T. Harayama."Dynamically Maintainig the Widest k-dense Corridor,"
Proc. 4th Italian Conf. on Algorithms and Complexity, CIAC 2000, pp.187-198,
[41] T. Asano,
[40] T. Asano, M. de Berg, O. Cheong, L. J. Guibas,
J. Snoeyink and H. Tamaki: "Spanning trees crossing few barriers,"
Proc. the Fifteenth Annual Symposium on Computational Geometry, pp.41-48, June
1999.
[39]T. Asano and Y. Kawamura: "Computational Comparison of Voting-based and
Arrangement-based Schema for Digital Line Extraction," Abstracts for the 11th Canadian Conf. on
Computational Geometry, pp.115-118, August 1999.
[38]T. Asano and Y. Kawamura: "Computational Complexity of the Digital Line Extraction
Problem," Proc.
Korea-Japan Joint Workshop on Algorithms and Computation, pp.54-58, July 1999.
[37] A. Hernandez-Barrerra, S. C. Nandy,
and T. Asano: "The Minkowski sum of a convex
polyhedron and a polyhedral terrain," Proc. 15th European
Workshop on Computational Geometry, March 1999.
[36] T. Asano: "Geometric Clustering Algorithms and Related Topics," Proc.
Japan Conf. on Discrete and Computational Geometry '98, pp.99-113,
[35] T. Asano, N. Katoh, H. Tamaki, and T.
Tokuyama: "Convertibility among Grid Filling Curves," Proc.
ISAAC'98 (Int. Symp. on Algorithms and Computation),
pp.307-316,
[34] T. Asano, H. Ito, S. Kimura, and S. Shimazu: "Repairing Flaws in
a Picture Based on a Geometric Representation of a Digital Image," Proc.
ISAAC'98 (Int. Symp. on Algorithms and Computation),
pp.149-158,
[33] T. Asano, N. Katoh, T. Tokuyama, and H. Tamaki:
"Covering
Points in the plane by k-tours: towards a polynomial time approximation scheme
for general k," Proc. 29th ACMSymp.
on Theory of Computing, pp.275-283,
[32] T. Asano: "Space-Efficient Algorithm for Image Segmentation," Proc.
Korea-Japan Joint Workshop on Algorithms and Computation, pp.59-66, August,
1996.
[31] T. Asano: "Digital Halftoning Algorithm Based
on a Random Space Filling Curve," Proc. International
Conf. on Image Processing, ICIP-96, pp.545-548,
[30] T. Asano, D.Kirkpatrick and C. K.
Yap: "d1-optimal
motion for a rod," Proc. 12th ACMSymp.
on Computational Geometry, pp.252-263,
[29] T. Asano, D.Z. Chen, N. Katoh, and T.
Tokuyama: "Polynomial-time Solutions to Image Segmentation," Proc.
of the 7th Annual SIAM-ACM Conference on Discrete Algorithms, pp.104-113,
[28] T. Asano, N. Katoh, E. Lodi and T. Roos: "Optimal Approximation of Monotone Curves on a Grid," Proc.
7th Canadian Conference on Computational Geometry, pp. 37-42,
[27] T. Asano and S. Kimura: "Contour Representation of an Image with Applications," Proc.
SPIE's International Symposium on Vision Geometry IV, pp. 14-22,
[26] T. Roos, T. Asano, D. Ranjan,
[25] T. Asano: "Reporting and Counting Intersections of Lines within a Polgon," Proc. Fifth International
Symposium on Algorithms and Computation, pp.652-659,
[24] T. Asano, N. Katoh, and T. Tokuyama: "A Unified Scheme
for Detecting Fundamental Curves in Binary Edge Images," Proc.
2nd European Symposium on Algorithms, pp.215-226,
[23] T. Asano, T. Tokuyama: "Topological Walk Revisited," Proc. 6th
Canadian Conference on Computational Geometry, pp. 1-6,
[22] T. Asano: "Applications of Optimization Techniques to Computer Vision," ABSTRACTS
of the Third Conference of the Association of Asian-Pacific Operational
Research Societies within IFORS, W-2-B-1, p.141,
[21] T. Asano, A. Hasegawa, D. Ranjan and T. Roos, "Optimal and approximate digital halftoning
algorithms and their experimental evaluation," Proc. Asian
Conference on Computer Vision, pp.379-381,
[20] T. Asano and N. Katoh: "Number Theory
Helps Line Detection in Digital Images," Proc. Fourth
International Symposium on Algorithms and Computation, pp.313-322,
[19] N. Kanamaru, T. Nishizeki
and T. Asano: "Efficient Enumeration of Grid Points in a Polygon and its
Application to Integer Programming," Proc. Second Integer
Programming and Combinatorial Optimization Conference, pp.61-71, 1992.
[18] T. Asano and T. Tokuyama: "Circuit Partitioning Algorithms: Graph Model versus Geometry
Model," Proc. 2nd International Symposium on Algorithms,
pp.94-103,
[17] T. Asano, L. J. Guibas and T.
Tokuyama: "Walking on an Arrangement Topologically," Proc.
Annual ACM Symp. on Computational Geometry,
pp.297-306,
[16] T. Asano and T. Tokuyama: "Algorithms for Projecting Points to Give the Most Uniform
Distribution with Applications to Hashing," Proc. the
First SIGAL International Symposium on Algorithms, pp.300-309,
[15] T. Asano, J. Hershberger, J. Pach, E. Sontag, D.
Souvaine, and S. Suri: "Separating
Bi-Chromatic Points by Parallel Lines," Abstracts of the
Second Canadian Conference on Computaitonal Geometry,
pp.46-49, Ottawa, 1990.
[14] T. Asano, M. E. Houle, H. Imai and K.
Imai: "A Unified Linear-Space Approach to Geometric Minimax
Problems," Abstracts of the Second Canadian Conference on Computaitonal Geometry, pp.20-23,
[13] T. Asano, H. Imai and K. Imai: "Clustering/Hashing Points in the Plane with Maxmin Criteria," Abstracts of The
First Canadian Conference on Computational Geometry, p.15,
[12] T. Asano: "Difficulty of Maximum Independent Set Problem on
Intersection Graphs of Geometric Objects," Graph Theory, Combinatorics, and Applications, John Wiley \& Sons,
1991 (as Proc. 4th Conference on Graph Theory and Its Applications, Kalamazoo,
Michigan, 1988), pp.9-18, 1988.
[11] Tetsuo Asano and Hiroshi Umeo: "Systolic
Algorithms for Computing the Visibility Polygon and Triangulation of a
Polygonal Region," International Workshop on Parallel
Algorithms and Architectures,
[10] T. Asano, B. Bhattacharya, J.M. Keil, and F.F.
Yao: "Clustering
Algorithms Based on Minimum and Maximum Spanning Trees," Proc.
of the 4th Annual ACM Symposium on Computational Geometry, pp.252-257,
[9] T. Asano and G. T. Toussaint: "Computing the
[8] Takao Asano and Tetsuo Asano: "Voronoi Diagram in a
Simple Polygon," Proc. of the Japan-U.S.A. Joint Seminar
on Discrete Algorithms and Complexity Theory,
[7] Takao Asano, Tetsuo Asano, L. Guibas, J.
Hershberger, H. Imai: "Visibility Polygon Search and Euclidean Shortest Paths," Proc.
26th IEEE Symp. on Foundations of Computer Science,
pp.155-164, 1985.
[6] W. M. Dai and T. Asano: "A New Routing Region Definition and Ordering Scheme Using
L-Shaped Channels," Proc. IEEE Int. Symp.
on Circuits and Systems, pp.29-30, 1985.
[5] T. Asano: "An Efficient Algorithm for Computing the Reachability
Polygon from a Point: Rectilinear Case," Proc. IEEE Int. Symp. on Circuits and Systems, pp.1293-1296, 1985.
[4] T. Asano and S. Sato: "Long Path Enumeration Algorithms for
Timing Verification on Large Digital Systems," Graph Theory with Applications to
Algorithms and Computer Science, Edited by Y. Alavi
et al., pp.25-36, John Wiley and Sons, Inc., 1985 as the Proc. of the Conf. on
Theory and Applications of Graphs, Michigan, June 1984.
[3] T. Asano: "Parametric Pattern Router," Proc. 19th
Design Automation Conf., pp.411-417, June 1982.
[2]Tetsuo Asano and Takao Asano::"Minimum Partition
of Polygonal Regions into Trapezoids," Proc. 24th IEEE Symp. on Foundations of Computer Science, pp.233-241, 1983.
[1] N. Yokoya, T. Kitahashi,
K. Tanaka, and T. Asano: "Image Segmentation
Scheme Based on a Concept of relative Similarity,"
Proc. 4th Int. Joint Conf. on Pattern Recognition, pp.645-647, 1978.