Next Issue
Previous Issue

Table of Contents

Symmetry, Volume 9, Issue 2 (February 2017)

  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Readerexternal link to open them.
Cover Story We introduced the class of Cyclotomic Aperiodic Substitution Tilings (CASTs) which covers a wide [...] Read more.
View options order results:
result details:
Displaying articles 1-9
Export citation of selected articles as:

Editorial

Jump to: Research, Other

Open AccessEditorial Acknowledgement to Reviewers of Symmetry in 2016
Symmetry 2017, 9(2), 20; doi:10.3390/sym9020020
Received: 26 January 2017 / Accepted: 26 January 2017 / Published: 26 January 2017
PDF Full-text (168 KB) | HTML Full-text | XML Full-text
Abstract
The editors of Symmetry would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2016.[...] Full article

Research

Jump to: Editorial, Other

Open AccessArticle Cyclotomic Aperiodic Substitution Tilings
Symmetry 2017, 9(2), 19; doi:10.3390/sym9020019
Received: 28 September 2016 / Revised: 18 December 2016 / Accepted: 4 January 2017 / Published: 25 January 2017
PDF Full-text (2984 KB) | HTML Full-text | XML Full-text
Abstract
The class of Cyclotomic Aperiodic Substitution Tilings (CASTs) is introduced. Its vertices are supported on the 2n-th cyclotomic field. It covers a wide range of known aperiodic substitution tilings of the plane with finite rotations. Substitution matrices and minimal inflation multipliers
[...] Read more.
The class of Cyclotomic Aperiodic Substitution Tilings (CASTs) is introduced. Its vertices are supported on the 2 n -th cyclotomic field. It covers a wide range of known aperiodic substitution tilings of the plane with finite rotations. Substitution matrices and minimal inflation multipliers of CASTs are discussed as well as practical use cases to identify specimen with individual dihedral symmetry D n or D 2 n , i.e., the tiling contains an infinite number of patches of any size with dihedral symmetry D n or D 2 n only by iteration of substitution rules on a single tile. Full article
Figures

Figure 1

Open AccessArticle Aesthetic Patterns with Symmetries of the Regular Polyhedron
Symmetry 2017, 9(2), 21; doi:10.3390/sym9020021
Received: 14 December 2016 / Revised: 18 January 2017 / Accepted: 22 January 2017 / Published: 3 February 2017
PDF Full-text (2270 KB) | HTML Full-text | XML Full-text
Abstract
A fast algorithm is established to transform points of the unit sphere into fundamental region symmetrically. With the resulting algorithm, a flexible form of invariant mappings is achieved to generate aesthetic patterns with symmetries of the regular polyhedra. Full article
(This article belongs to the Special Issue Polyhedral Structures)
Figures

Open AccessArticle A Study on Immersion of Hand Interaction for Mobile Platform Virtual Reality Contents
Symmetry 2017, 9(2), 22; doi:10.3390/sym9020022
Received: 11 October 2016 / Revised: 24 January 2017 / Accepted: 30 January 2017 / Published: 5 February 2017
PDF Full-text (20627 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
This study proposes gaze-based hand interaction, which is helpful for improving the user’s immersion in the production process of virtual reality content for the mobile platform, and analyzes efficiency through an experiment using a questionnaire. First, three-dimensional interactive content is produced for use
[...] Read more.
This study proposes gaze-based hand interaction, which is helpful for improving the user’s immersion in the production process of virtual reality content for the mobile platform, and analyzes efficiency through an experiment using a questionnaire. First, three-dimensional interactive content is produced for use in the proposed interaction experiment while presenting an experiential environment that gives users a high sense of immersion in the mobile virtual reality environment. This is designed to induce the tension and concentration of users in line with the immersive virtual reality environment. Additionally, a hand interaction method based on gaze—which is mainly used for the entry of mobile virtual reality content—is proposed as a design method for immersive mobile virtual reality environment. The user satisfaction level of the immersive environment provided by the proposed gaze-based hand interaction is analyzed through experiments in comparison with the general method that uses gaze only. Furthermore, detailed analysis is conducted by dividing the effects of the proposed interaction method on user’s psychology into positive factors such as immersion and interest and negative factors such as virtual reality (VR) sickness and dizziness. In this process, a new direction is proposed for improving the immersion of users in the production of mobile platform virtual reality content. Full article
(This article belongs to the Special Issue Symmetry in Complex Networks II)
Figures

Open AccessArticle Single Image Super-Resolution by Non-Linear Sparse Representation and Support Vector Regression
Symmetry 2017, 9(2), 24; doi:10.3390/sym9020024
Received: 31 July 2016 / Accepted: 2 February 2017 / Published: 10 February 2017
PDF Full-text (1308 KB) | HTML Full-text | XML Full-text
Abstract
Sparse representations are widely used tools in image super-resolution (SR) tasks. In the sparsity-based SR methods, linear sparse representations are often used for image description. However, the non-linear data distributions in images might not be well represented by linear sparse models. Moreover, many
[...] Read more.
Sparse representations are widely used tools in image super-resolution (SR) tasks. In the sparsity-based SR methods, linear sparse representations are often used for image description. However, the non-linear data distributions in images might not be well represented by linear sparse models. Moreover, many sparsity-based SR methods require the image patch self-similarity assumption; however, the assumption may not always hold. In this paper, we propose a novel method for single image super-resolution (SISR). Unlike most prior sparsity-based SR methods, the proposed method uses non-linear sparse representation to enhance the description of the non-linear information in images, and the proposed framework does not need to assume the self-similarity of image patches. Based on the minimum reconstruction errors, support vector regression (SVR) is applied for predicting the SR image. The proposed method was evaluated on various benchmark images, and promising results were obtained. Full article
(This article belongs to the Special Issue Symmetry in Systems Design and Analysis)
Figures

Figure 1

Open AccessArticle Deformable Object Matching Algorithm Using Fast Agglomerative Binary Search Tree Clustering
Symmetry 2017, 9(2), 25; doi:10.3390/sym9020025
Received: 7 November 2016 / Revised: 5 January 2017 / Accepted: 4 February 2017 / Published: 10 February 2017
PDF Full-text (3385 KB) | HTML Full-text | XML Full-text
Abstract
Deformable objects have changeable shapes and they require a different method of matching algorithm compared to rigid objects. This paper proposes a fast and robust deformable object matching algorithm. First, robust feature points are selected using a statistical characteristic to obtain the feature
[...] Read more.
Deformable objects have changeable shapes and they require a different method of matching algorithm compared to rigid objects. This paper proposes a fast and robust deformable object matching algorithm. First, robust feature points are selected using a statistical characteristic to obtain the feature points with the extraction method. Next, matching pairs are composed by the feature point matching of two images using the matching method. Rapid clustering is performed using the BST (Binary Search Tree) method by obtaining the geometric similarity between the matching pairs. Finally, the matching of the two images is determined after verifying the suitability of the composed cluster. An experiment with five different image sets with deformable objects confirmed the superior robustness and independence of the proposed algorithm while demonstrating up to 60 times faster matching speed compared to the conventional deformable object matching algorithms. Full article
(This article belongs to the Special Issue Symmetry in Complex Networks II)
Figures

Figure 1

Open AccessArticle A Symmetry Particle Method towards Implicit Non‐Newtonian Fluids
Symmetry 2017, 9(2), 26; doi:10.3390/sym9020026
Received: 17 January 2017 / Accepted: 10 February 2017 / Published: 17 February 2017
Cited by 1 | PDF Full-text (1601 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, a symmetry particle method, the smoothed particle hydrodynamics (SPH) method, is extended to deal with non‐Newtonian fluids. First, the viscous liquid is modeled by a non‐Newtonian fluid flow and the variable viscosity under shear stress is determined by the Carreau‐Yasuda
[...] Read more.
In this paper, a symmetry particle method, the smoothed particle hydrodynamics (SPH) method, is extended to deal with non‐Newtonian fluids. First, the viscous liquid is modeled by a non‐Newtonian fluid flow and the variable viscosity under shear stress is determined by the Carreau‐Yasuda model. Then a pressure correction method is proposed, by correcting density error with individual stiffness parameters for each particle, to ensure the incompressibility of fluid. Finally, an implicit method is used to improve efficiency and stability. It is found that the nonNewtonian behavior can be well displayed in all cases, and the proposed SPH algorithm is stable and efficient. Full article
(This article belongs to the Special Issue Symmetry in Cooperative Applications II)
Figures

Figure 1

Open AccessArticle Symmetry Analysis and Conservation Laws of the Zoomeron Equation
Symmetry 2017, 9(2), 27; doi:10.3390/sym9020027
Received: 27 October 2016 / Accepted: 10 February 2017 / Published: 21 February 2017
PDF Full-text (256 KB) | HTML Full-text | XML Full-text
Abstract
In this work, we study the (2 + 1)-dimensional Zoomeron equation which is an extension of the famous (1 + 1)-dimensional Zoomeron equation that has been studied extensively in the literature. Using classical Lie point symmetries admitted by the equation, for the first
[...] Read more.
In this work, we study the (2 + 1)-dimensional Zoomeron equation which is an extension of the famous (1 + 1)-dimensional Zoomeron equation that has been studied extensively in the literature. Using classical Lie point symmetries admitted by the equation, for the first time we develop an optimal system of one-dimensional subalgebras. Based on this optimal system, we obtain symmetry reductions and new group-invariant solutions. Again for the first time, we construct the conservation laws of the underlying equation using the multiplier method. Full article

Other

Jump to: Editorial, Research

Open AccessErratum Erratum: Rauh, A. Coherent States of Harmonic and Reversed Harmonic Oscillator. Symmetry, 2016, 8, 46
Symmetry 2017, 9(2), 23; doi:10.3390/sym9020023
Received: 6 February 2017 / Accepted: 6 February 2017 / Published: 9 February 2017
PDF Full-text (158 KB) | HTML Full-text | XML Full-text

Journal Contact

MDPI AG
Symmetry Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
E-Mail: 
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Symmetry Edit a special issue Review for Symmetry
logo
loading...
Back to Top