Special Issue "Symmetry in Theoretical Computer Science"

Guest Editor
Prof. Dr. Takeshi Koshiba
Area of Informatics, Division of Mathematics, Electronics and Informatics, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan
Website: http://www.tcs.ics.saitama-u.ac.jp/~koshiba/
E-Mail:
Interests: theory of cryptography; randomness and computation; quantum computation; computational complexity

Dear Colleagues,

Symmetry is a basic concept even in Theoretical Computer Science. For the design and analysis of the algorithms, the symmetry plays an important role. The symmetry often makes the probabilistic analysis of randomized algorithms easier and simpler. Sometimes, the incorporation of elegant methods of symmetry- or tie- breaking into algorithms leads to the efficiency. Moreover, symmetric structures and patterns are omnipresent and the study of their algorithmic or computational aspects gives us an understanding of the nature of the symmetry.

Contributions are invited on all aspects of symmetry in theoretical computer science. Those that involve other fields are welcomed if they are discussed from the algorithmic or computational point of view.

Prof. Dr. Takeshi Koshiba
Guest Editor

Submission

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Symmetry is an international peer-reviewed Open Access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 300 CHF (Swiss Francs). English correction and/or formatting fees of 250 CHF (Swiss Francs) will be charged in certain cases for those articles accepted for publication that require extensive additional formatting and/or English corrections.

• randomized algorithm
• probabilistic analysis
• symmetric break / tie break
• distributed computing
• algorithmic game theory
• symmetric network
• symmetric structure / pattern

Type of Paper: Article
Title: On Perception of Symmetry and Balance in 2D and 3D images
Author: Ihar Volkau, Varsha Gupta, Fiftarina Puspitasari and Wieslaw L. Nowinski
Affiliation: Biomedical Imaging Lab, Singapore Bio-imaging Consortium, Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, Singapore, 138671, E-Mail: igor@sbic.a-star.edu.sg (I.H.)
Abstract: The symmetry and asymmetry of objects are important features which help perceiving 2D and 3D scenes. To some extent, symmetry as well as asymmetry can be identified at any spot of an object. Some objects can be considered as roughly symmetrical – similar in some sense but not identical (e.g. brain hemispheres). We refer to such rough symmetry as balance. The perfect balance is generally perceived as symmetry. There exist several ways to quantify balance in mathematical terms. We propose a method to identify the axis of balance following the results of analysis of eye tracking. Mathematically the approach is based on the behavior of Kullback-Leibler’s measure, which is a widely used tool in statistics. Additional analysis is used to quantify symmetry between two regions. The method does not require preliminary segmentation, and can cope, to some extent, with image noise, artifacts, and blurred images. The method is demonstrated using 2D and 3D images of symmetrical and balanced objects. Currently the method is applied in the area of biomedical image processing for pathology detection and stroke analysis, as violation of symmetry is one of the frequent manifestations of abnormalities.