Special Issue "Computational Geometry"

Editorial Board Member
Dr. Adrian Dumitrescu
University of Wisconsin-Milwaukee; 3200 N. Cramer Street Milwaukee, WI 53211, USA
Website: http://www.cs.uwm.edu/faculty/ad/
E-mail:

Editorial Board Member
Prof. Dr. Takeshi Tokuyama
Graduate School of Information Sciences (GSIS), Tohoku University, Aramaki Aza-Aoba, Aoba, Sendai, 980-8579, Japan
Website: http://www.dais.is.tohoku.ac.jp/~tokuyama/profile_e.htm
E-mail:

"Computational geometry is a branch of computer science devoted to the study of algorithms which can be stated in terms of geometry. Some purely geometrical problems arise out of the study of computational geometric algorithms, and such problems are also considered to be part of computational geometry." (from http://en.wikipedia.org/wiki/Computational_geometry)

Submissions

All papers should be submitted to algorithms@mdpi.org. To be published continuously until the deadline and papers will be listed together at the special website.

Submitted papers should not have been previously published nor currently under consideration for publication elsewhere. All papers are refereed through a peer review process. A guide for authors is available on the Instructions for Authors page. Algorithms is an international peer-reviewed quarterly journal published by Molecular Diversity Preservation International.

Open Access publication fees are 300 CHF per paper. English correction fees and/or formatting fees (250 CHF) will be added in certain cases (550 CHF per paper for those papers that require extensive additional formatting and/or English corrections.).

Article Processing Charges (APC)

Article Processing Charges (APC) will be waived for well prepared manuscripts of invited papers. For the first two volumes of this new journal the APC are of 300 CHF (or 550 CHF per paper for those papers that require extensive additional formatting and/or English corrections).

• combinatorial computational geometry
• algorithmic geometry
• numerical computational geometry (machine geometry)
• computer-aided geometric design (CAGD)
• geometric modeling

Title: Delaunay Meshing of Piecewise Smooth Complexes without Expensive Predicates
Authors: Tamal K. Dey and Joshua A. Levine
Affiliation: Dept. of CSE, The Ohio State University
Abstract: Recently a Delaunay refinement algorithm has been proposed that can mesh piecewise smooth complexes which include polyhedra, smooth and piecewise smooth surfaces, and non-manifolds. However, this algorithm employs domain dependent numerical predicates, some of which could be computationally expensive and hard to implement. In this paper we develop a refinement strategy that eliminates these complicated domain dependent predicates. As a result we obtain a meshing algorithm that is practical and implementation-friendly.

Title: Variants of the lion problem
Authors: Florian Berger, Alexander Gilbers, Ansgar Grüne and Rolf Klein
Affiliation: Institute of Computer Science, Dept. I, University of Bonn
Abstract: A pride of lions are prowling among the vertices and edges of a grid graph. If their paths are known in advance, is it possible to design a safe path for a man that avoids all lions? Brass et al. showed that n/2 lions can always be avoided. We analyze the high dimensional case as well as the problem variant where the lions are allowed to jump over large distances.

Title: 2-Covering a polygonal region
Authors: Manuel Abellanas, Antonio L. Bajuelos, Inês Matos
Abstract: Wireless sensor networks are used to solve a diversity of problems that range from battlefield monitoring to weather analysis. Let S be a set of homogeneous wireless sensors with transmission range r. The optimisation problems presented in this work aim to completely cover a given region so that every point is within the range of at least two sensors of S. This particularisation is useful since it assures that the region remains covered when one sensor fails. The sensor's transmission range depends directly on its transmission power which, in its turn, is responsible for the costs associated to the services it provides. It is therefore interesting to minimise the value of r.

Title: Compound Biorthogonal Wavelets based on Bicubic B-spline Subdivisions
Authors: Chong Zhao¹, Hanqiu Sun¹, Huawei Wang², Kaihuai Qin³
Affiliations: ¹Dept. of Computer Science & Eng., The Chinese University of Hong Kong, Hong Kong
²Dept. of Manufacturing Eng. and Eng. Man., City University of Hong Kong, HK
³Dept. of Computer Science & Technology, Tsinghua University, Beijing
Abstract : In this paper, we present the novel compound biorthogonal wavelets based on bicubic B-spline subdivisions, which can offer a large number of resolution levels to control nets with polar structures. The wavelet analysis supports more resolution levels to the meshes with high valence extraordinary vertices or the combinatorial structures of objects of revolution. Because we only use local lifting operations to ensure the local orthogonalization of wavelet, the computations are fully in-place and the complexity is linear time. The fully in-place computation eliminates the need of auxiliary memory cost of the algorithm. It can be easily combined with Catmull-Clark subdivision and constitute a composite wavelet which could perform on quadrilateral meshes mixed with polar structures. Comparing to the all-quads layout favored, the polar structure is more natural at the points of high valence. The existing subdivision wavelets such as Catmull-Clark subdivision wavelets are not suitable to represent the multi-resolution polar structures because the base subdivision may generate the saddle points and ripples in the points of high valence.