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  • 1
    Publication Date: 2018-07-26
    Description: Symmetry, Vol. 10, Pages 300: Computing Metric Dimension and Metric Basis of 2D Lattice of Alpha-Boron Nanotubes Symmetry doi: 10.3390/sym10080300 Authors: Zafar Hussain Mobeen Munir Maqbool Chaudhary Shin Min Kang Concepts of resolving set and metric basis has enjoyed a lot of success because of multi-purpose applications both in computer and mathematical sciences. For a connected graph G(V,E) a subset W of V(G) is a resolving set for G if every two vertices of G have distinct representations with respect to W. A resolving set of minimum cardinality is called a metric basis for graph G and this minimum cardinality is known as metric dimension of G. Boron nanotubes with different lattice structures, radii and chirality’s have attracted attention due to their transport properties, electronic structure and structural stability. In the present article, we compute the metric dimension and metric basis of 2D lattices of alpha-boron nanotubes.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 2
    Publication Date: 2018-07-26
    Description: Symmetry, Vol. 10, Pages 299: Game-Theoretic Solutions for Data Offloading in Next Generation Networks Symmetry doi: 10.3390/sym10080299 Authors: Muhammad Asif Shafi Ullah Khan Rashid Ahmad Dhananjay Singh In recent years, global mobile data traffic has seen an unprecedented increase. This is due to worldwide usage of smart devices, availability of fast internet connections, and the popularity of social media. The Mobile Network Operators (MNOs) are, therefore, facing problems in handling this huge traffic flow. Each type of traffic, including real-time video, audio, and text has its own Quality of Services (QoS) requirements which, if not met, may cause a sufficient loss of profit. Offloading of these traffics can be made more efficient so that values of QoS parameters are enhanced. In this work, we propose an incentive-based game-theoretic frame work for downloading data. The download of each type of data will get an incentive determined by the two-stage Stackelberg game. We model the communication among single Mobile Base Station (MBS) and multiple Access Points (APs) in a crowded metropolitan environment. The leader offers an economic incentive based on the traffic type and followers respond to the incentive and offload traffic accordingly. The model optimizes strategies of both the MBS and APs in order to make the best use of their utilities. For the analysis, we have used a combination of analytical and experimental methods. The numerical outcome characterized a direct process of the best possible offloading ratio and legalized the efficiency of the proposed game. Optimal incentives and optimal offloading was the achievement of our proposed game-theoretic approach. We have implemented the model in MATLAB, and the experimental results show a maximum payoff was achieved and the proposed scheme achieved Nash Equilibria.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 3
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 315: Long Time Behavior and Global Dynamics of Simplified Von Karman Plate Without Rotational Inertia Driven by White Noise Symmetry doi: 10.3390/sym10080315 Authors: Huatao Chen Dengqing Cao Jingfei Jiang Xiaoming Fan Without the assumption that the coefficient of weak damping is large enough, the existence of the global random attractors for simplified Von Karman plate without rotational inertia driven by either additive white noise or multiplicative white noise are proved. Instead of the classical splitting method, the techniques to verify the asymptotic compactness rely on stabilization estimation of the system. Furthermore, a clear relationship between in-plane components of the external force that act on the edge of the plate and the expectation of radius of the global random attractors can be obtained from the theoretical results. Based on the relationship between global random attractor and random probability invariant measure, the global dynamics of the plates are analyzed numerically. With increasing the in-plane components of the external force that act on the edge of the plate, global D-bifurcation, secondary global D-bifurcation and complex local dynamical behavior occur in motion of the system. Moreover, increasing the intensity of white noise leads to the dynamical behavior becoming simple. The results on global dynamics reveal that random snap-through which seems to be a complex dynamics intuitively is essentially a simple dynamical behavior.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 4
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 314: Systematic Review of Decision Making Algorithms in Extended Neutrosophic Sets Symmetry doi: 10.3390/sym10080314 Authors: Mohsin Khan Le Hoang Son Mumtaz Ali Hoang Thi Minh Chau Nguyen Thi Nhu Na Florentin Smarandache The Neutrosophic set (NS) has grasped concentration by its ability for handling indeterminate, uncertain, incomplete, and inconsistent information encountered in daily life. Recently, there have been various extensions of the NS, such as single valued neutrosophic sets (SVNSs), Interval neutrosophic sets (INSs), bipolar neutrosophic sets (BNSs), Refined Neutrosophic Sets (RNSs), and triangular fuzzy number neutrosophic set (TFNNs). This paper contains an extended overview of the concept of NS as well as several instances and extensions of this model that have been introduced in the last decade, and have had a significant impact in literature. Theoretical and mathematical properties of NS and their counterparts are discussed in this paper as well. Neutrosophic-set-driven decision making algorithms are also overviewed in detail.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 5
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 311: On p-Adic Fermionic Integrals of q-Bernstein Polynomials Associated with q-Euler Numbers and Polynomials † Symmetry doi: 10.3390/sym10080311 Authors: Lee-Chae Jang Taekyun Kim Dae San Kim Dmitry Victorovich Dolgy We study a q-analogue of Euler numbers and polynomials naturally arising from the p-adic fermionic integrals on Zp and investigate some properties for these numbers and polynomials. Then we will consider p-adic fermionic integrals on Zp of the two variable q-Bernstein polynomials, recently introduced by Kim, and demonstrate that they can be written in terms of the q-analogues of Euler numbers. Further, from such p-adic integrals we will derive some identities for the q-analogues of Euler numbers.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 6
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 312: Connecting Electroweak Symmetry Breaking and Flavor: A Light Dilaton D and a Sequential Heavy Quark Doublet Q Symmetry doi: 10.3390/sym10080312 Authors: Wei-Shu Hou The 125 GeV boson is quite consistent with the Higgs boson of the Standard Model (SM), but there is a challenge from Anderson as to whether this particle is in the Lagrangian. As Large Hadron Collider (LHC) Run 2 enters its final year of running, we ought to reflect and make sure we have gotten everything right. The ATLAS and CMS combined Run 1 analysis claimed a measurement of 5.4σ vector boson fusion (VBF) production which is consistent with SM, which seemingly refutes Anderson. However, to verify the source of electroweak symmetry breaking (EWSB), we caution that VBF measurement is too important for us to be imprudent in any way, and gluon–gluon fusion (ggF) with similar tag jets must be simultaneous measured, which should be achievable in LHC Run 2. The point is to truly test the dilaton possibility—the pseudo-Goldstone boson of scale invariance violation. We illustrate EWSB by dynamical mass generation of a sequential quark doublet (Q) via its ultrastrong Yukawa coupling and argue how this might be consistent with a 125 GeV dilaton, D. The ultraheavy 2mQ≳4–5 TeV scale explains the absence of New Physics so far, while the mass generation mechanism shields us from the UV theory for the strong Yukawa coupling. Collider and flavor physics implications are briefly touched upon. Current Run 2 analyses show correlations between the ggF and VBF measurements, but the newly observed tt¯H production at LHC poses a challenge.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 7
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 305: Evaluation of a Third-Party Logistics (3PL) Provider Using a Rough SWARA–WASPAS Model Based on a New Rough Dombi Agregator Symmetry doi: 10.3390/sym10080305 Authors: Siniša Sremac Željko Stević Dragan Pamučar Miloš Arsić Bojan Matić For companies active in various sectors, the implementation of transport services and other logistics activities has become one of the key factors of efficiency in the total supply chain. Logistics outsourcing is becoming more and more important, and there is an increasing number of third party logistics providers. In this paper, logistics providers were evaluated using the Rough SWARA (Step-Wise Weight Assessment Ratio Analysis) and Rough WASPAS (Weighted Aggregated Sum Product Assessment) models. The significance of the eight criteria on the basis of which evaluation was carried out was determined using the Rough SWARA method. In order to allow for a more precise consensus in group decision-making, the Rough Dombi aggregator was developed in order to determine the initial rough matrix of multi-criteria decision-making. A total of 10 logistics providers dealing with the transport of dangerous goods for chemical industry companies were evaluated using the Rough WASPAS approach. The obtained results demonstrate that the first logistics provider is also the best one, a conclusion confirmed by a sensitivity analysis comprised of three parts. In the first part, parameter ρ was altered through 10 scenarios in which only alternatives four and five change their ranks. In the second part of the sensitivity analysis, a calculation was performed using the following approaches: Rough SAW (Simple Additive Weighting), Rough EDAS (Evaluation Based on Distance from Average Solution), Rough MABAC (MultiAttributive Border Approximation Area Comparison), and Rough TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution). They showed a high correlation of ranks determined by applying Spearman’s correlation coefficient in the third part of the sensitivity analysis.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 8
    Publication Date: 2018-08-03
    Description: Symmetry, Vol. 10, Pages 318: Detectability Improved Tamper Detection Scheme for Absolute Moment Block Truncation Coding Compressed Images Symmetry doi: 10.3390/sym10080318 Authors: Wien Hong Xiaoyu Zhou Der-Chyuan Lou Xiaoqin Huang Cancan Peng Since digital media is gaining popularity nowadays, people are more concerned about its integrity protection and authentication since tampered media may result in unexpected problems. Considering a better media protection technique, this paper proposes an efficient tamper detection scheme for absolute moment block truncation coding (AMBTC) compressed images. In AMBTC, each image block is represented by two quantization levels (QLs) and a bitmap. Requiring insignificant computation cost, it attracts not only a wide range of application developers, but also a variety of studies to investigate the authentication of its codes. While the existing methods protect the AMBTC codes to a large extent, the leakage of some unprotected codes may be insensitive to intentional tampering. The proposed method fully protects the AMBTC codes by embedding authentication codes (ACs) into QLs. Meanwhile, the most significant bits of QLs are symmetrically perturbed to generate the candidates of ACs. The ACs that cause the minimum distortion are embedded into the least significant bits of QLs to minimize the distortion. When compared with prior works, the experimental results reveal that the proposed method offers a significant sensitivity-of-tamper property while providing a comparable image quality.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 9
    Publication Date: 2018-08-03
    Description: Symmetry, Vol. 10, Pages 319: CRCM: A New Combined Data Gathering and Energy Charging Model for WRSN Symmetry doi: 10.3390/sym10080319 Authors: Yuhou Wang Ying Dong Shiyuan Li Hao Wu Mengyao Cui With the development of wireless sensor networks (WSNs), the problem about how to increase the lifecycle of the WSNs is always a hot discussion point, and some researchers have devoted to the ‘energy saving’ to decrease the energy consumption of the sensor nodes by different algorithms. However, the fundamental technique is ‘energy acquiring’ for the battery which can solve the limited capacity problem. In this paper, we study the data gathering and energy charging by a mobile charger (MC) at the same time that most energy consumption can be saved by short communication distance. We have named this as the recharging model-combined recharging and collecting data model on-demand (CRCM). Firstly, the hexagon-based (HB) algorithm is proposed to sort all sensor nodes in the region to make data collecting and energy charging work at the same time. Then we consider both residual energy and geographic position (REGP) of the sensor node to calculate the priority of each cluster. Thirdly, the dynamic mobile charger (DMC) algorithm is proposed to calculate the number of MCs to make sure no sensor node will die in each charging queue. Finally, the simulations show that our REGP algorithm is better than Earliest Deadline First (EDF) and Nearest-Job-Next with Preemption (NJNP), and the DMC plays well when the number of sensor nodes increase.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 10
    Publication Date: 2018-08-07
    Description: Symmetry, Vol. 10, Pages 323: Temperature-Dependent s± ↔ s++ Transitions in the Multiband Model for Fe-Based Superconductors with Impurities Symmetry doi: 10.3390/sym10080323 Authors: V. A. Shestakov M. M. Korshunov O. V. Dolgov We study the dependence of the superconducting gaps on both the disorder and the temperature within the two-band model for iron-based materials. In the clean limit, the system is in the s± state with sign-changing gaps. Scattering by nonmagnetic impurities leads to the change of the sign of the smaller gap, resulting in a transition from the s± to the s++ state with the sign-preserving gaps. We show here that the transition is temperature-dependent. Thus, there is a line of s±→s++ transition in the temperature–disorder phase diagram. There is a narrow range of impurity scattering rates, where the disorder-induced s±→s++ transition occurs at low temperatures, but then the low-temperature s++ state transforms back to the s± state at higher temperatures. With increasing impurity scattering rate, the temperature of such s++→s± transition shifts to the critical temperature Tc, and only the s++ state is left for higher amounts of disorder.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 11
    Publication Date: 2018-06-12
    Description: Symmetry, Vol. 10, Pages 210: An Improved Whale Optimization Algorithm Based on Different Searching Paths and Perceptual Disturbance Symmetry doi: 10.3390/sym10060210 Authors: Wei-zhen Sun Jie-sheng Wang Xian Wei Whale optimization algorithm (WOA) is a swarm intelligence optimization algorithm inspired by humpback whale hunting behavior. WOA has many similarities with other swarm intelligence algorithms (PSO, GWO, etc.). WOA’s unique search mechanism enables it to have a strong global search capability while taking into account the strong global search capabilities. In this work, considering the the deficiency of WOA in local search mechanism, combined with the optimization methods of other group intelligent algorithms, perceptual perturbation mechanism is introduced, which makes the agent perform more detailed searches near the local extreme point. At the same time, since the WOA uses a logarithmic spiral curve, the agent cannot fully search all the spaces within its search range, even though the introduction of the perturbation mechanism may still lead to the algorithm falling into a local optimum. Therefore, the equal pitch Archimedes spiral curve is chosen to replace the classic logarithmic spiral curve. In order to fully verify the effect of the search path on the performance of the algorithm, several other spiral curves have been chosen for experimental comparison. By utilizing the 23 benchmark test functions, the simulation results show that WOA (PDWOA) with perceptual perturbation significantly outperforms the standard WOA. Then, based on the PDWOA, the effect of the search path on the performance of the algorithm has been verified. The simulation results show that the equal pitch of the Archimedean spiral curve is best.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 12
    Publication Date: 2018-06-05
    Description: Symmetry, Vol. 10, Pages 201: Topological Characterization of the Symmetrical Structure of Bismuth Tri-Iodide Symmetry doi: 10.3390/sym10060201 Authors: Muhammad Imran Muhammad Arfan Ali Sarfaraz Ahmad Muhammad Kamran Siddiqui Abdul Qudair Baig The bismuth tri-iodide ( B i I 3 ) is an inorganic compound. It is the result of the response of bismuth and iodine, which has inspired enthusiasm for subjective inorganic investigation. The topological indices are the numerical invariants of the molecular graph that portray its topology and are normally graph invariants. In 1975, Randic presented, in a bond-added substance, a topological index as a descriptor for portraying subatomic branching. In this paper, we investigate the precious stone structure of bismuth tri-iodide chain and sheet. Moreover, exact formulas of degree-based added-substance topological indices principally the first, second, and hyper Zagreb indices, the general Randic index, the geometric-arithmetic index, the fourth atom-bond connectivity index, and the fifth geometric arithmetic index of the subatomic graph of bismuth tri-iodide for both chain and sheet structures are determined.
    Electronic ISSN: 2073-8994
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  • 13
    Publication Date: 2018-06-14
    Description: Symmetry, Vol. 10, Pages 218: Gauss Map and Its Applications on Ruled Submanifolds in Minkowski Space Symmetry doi: 10.3390/sym10060218 Authors: Sun Jung Young Kim We study ruled submanifolds in Minkowski space in regard to the Gauss map satisfying some partial differential equation. As a generalization of usual cylinders, cones and null scrolls in a three-dimensional Minkowski space, a cylinder over a space curve, a product manifold of a right cone and a k-plane, a product manifold of a hyperbolic cone and a k-plane which look like kinds of cylinders over cones in 3-space, and the generalized B-scroll kind in Minkowski space are characterized with the partial differential equation regarding the Gauss map, where k is a positive integer.
    Electronic ISSN: 2073-8994
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  • 14
    Publication Date: 2018-06-14
    Description: Symmetry, Vol. 10, Pages 217: Decision-Making via Neutrosophic Support Soft Topological Spaces Symmetry doi: 10.3390/sym10060217 Authors: Parimala Mani Karthika Muthusamy Saeid Jafari Florentin Smarandache Udhayakumar Ramalingam The concept of interval neutrosophic sets has been studied and the introduction of a new kind of set in topological spaces called the interval valued neutrosophic support soft set has been suggested. We study some of its basic properties. The main purpose of this paper is to give the optimum solution to decision-making in real life problems the using interval valued neutrosophic support soft set.
    Electronic ISSN: 2073-8994
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  • 15
    Publication Date: 2018-06-13
    Description: Symmetry, Vol. 10, Pages 214: Intelligent Prognostics of Degradation Trajectories for Rotating Machinery Based on Asymmetric Penalty Sparse Decomposition Model Symmetry doi: 10.3390/sym10060214 Authors: Qing Li Steven Y. Liang The ability to accurately track the degradation trajectories of rotating machinery components is arguably one of the challenging problems in prognostics and health management (PHM). In this paper, an intelligent prediction approach based on asymmetric penalty sparse decomposition (APSD) algorithm combined with wavelet neural network (WNN) and autoregressive moving average-recursive least squares algorithm (ARMA-RLS) is proposed for degradation prognostics of rotating machinery, taking the accelerated life test of rolling bearings as an example. Specifically, the health indicators time series (e.g., peak-to-peak value and Kurtosis) is firstly decomposed into low frequency component (LFC) and high frequency component (HFC) using the APSD algorithm; meanwhile, the resulting non-convex regularization problem can be efficiently solved using the majorization-minimization (MM) method. In particular, the HFC part corresponds to the stable change around the zero line of health indicators which most extensively occurs; in contrast, the LFC part is essentially related to the evolutionary trend of health indicators. Furthermore, the nonparametric-based method, i.e., WNN, and parametric-based method, i.e., ARMA-RLS, are respectively introduced to predict the LFC and HFC that focus on abrupt degradation regions (e.g., last 100 points). Lastly, the final predicted data could be correspondingly obtained by integrating the predicted LFC and predicted HFC. The proposed methodology is tested using degradation health indicator time series from four rolling bearings. The proposed approach performed favorably when compared to some state-of-the-art benchmarks such as WNN and largest Lyapunov (LLyap) methods.
    Electronic ISSN: 2073-8994
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  • 16
    Publication Date: 2018-06-15
    Description: Symmetry, Vol. 10, Pages 222: Bayer Image Demosaicking Using Eight-Directional Weights Based on the Gradient of Color Difference Symmetry doi: 10.3390/sym10060222 Authors: Yizheng Liu Chengyou Wang Hongming Zhao Jiayang Song Shiyue Chen In this paper, we propose a new demosaicking algorithm which uses eight-directional weights based on the gradient of color difference (EWGCD) for Bayer image demosaicking. To obtain the interpolation of green (G) pixels, the eight-directional G pixel values are first estimated in red (R)/blue (B) pixels. This estimate is used to calculate the color difference in R/B pixels of the Bayer image in diagonal directions. However, in horizontal and vertical directions, the new estimated G pixels are defined to obtain the color difference. The eight-directional weights of estimated G pixels can be obtained by considering the gradient of the color difference and the gradient of the RGB pixels of the Bayer image. Therefore, the eight-directional weighted values and the first estimated G pixel values are combined to obtain the full G image. Compared with six similar algorithms using the same eighteen McMaster images, the results of the experiment demonstrate that the proposed algorithm has a better performance not only in the subjective visual measurement but also in the assessments of peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) index measurement.
    Electronic ISSN: 2073-8994
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  • 17
    Publication Date: 2018-06-22
    Description: Symmetry, Vol. 10, Pages 231: Observers and Their Notion of Spacetime beyond Special Relativity Symmetry doi: 10.3390/sym10070231 Authors: José Manuel Carmona José Luis Cortés José Javier Relancio It is plausible that quantum gravity effects may lead us to a description of Nature beyond the framework of special relativity. In this case, either the relativity principle is broken or it is maintained. These two scenarios (a violation or a deformation of special relativity) are very different, both conceptually and phenomenologically. We discuss some of their implications on the description of events for different observers and the notion of spacetime.
    Electronic ISSN: 2073-8994
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  • 18
    Publication Date: 2018-06-22
    Description: Symmetry, Vol. 10, Pages 233: Symmetries of Differential Equations in Cosmology Symmetry doi: 10.3390/sym10070233 Authors: Michael Tsamparlis Andronikos Paliathanasis The purpose of the current article is to present a brief albeit accurate presentation of the main tools used in the study of symmetries of Lagrange equations for holonomic systems and subsequently to show how these tools are applied in the major models of modern cosmology in order to derive exact solutions and deal with the problem of dark matter/energy. The key role in this approach are the first integrals of the field equations. We start with the Lie point symmetries and the first integrals defined by them, that is, the Hojman integrals. Subsequently, we discuss the Noether point symmetries and the well-known method for deriving the Noether integrals. By means of the Inverse Noether Theorem, we show that, to every Hojman quadratic first integral, it is possible to associate a Noether symmetry whose Noether integral is the original Hojman integral. It is emphasized that the point transformation generating this Noether symmetry need not coincide with the point transformation defining the Lie symmetry which produces the Hojman integral. We discuss the close connection between the Lie point and the Noether point symmetries with the collineations of the metric defined by the kinetic energy of the Lagrangian. In particular, the generators of Noether point symmetries are elements of the homothetic algebra of that metric. The key point in the current study of cosmological models is the introduction of the mini superspace, which is the space that is defined by the physical variables of the model, which is not the spacetime where the model evolves. The metric in the mini superspace is found from the kinematic part of the Lagrangian and we call it the kinetic metric. The rest part of the Lagrangian is the effective potential. We consider coordinate transformations of the original mini superspace metric in order to bring it to a form where we know its collineations, that is, the Killing vectors, the homothetic vector, etc. Then, we write the field equations of the cosmological model and we use the connection of these equations with the collineations of the mini superspace metric to compute the first integrals and subsequently to obtain analytic solutions for various allowable potentials and finally draw conclusions about the problem of dark energy. We consider the ΛCDM cosmological model, the scalar field cosmology, the Brans–Dicke cosmology, the f(R) gravity, the two scalar fields cosmology with interacting scalar fields and the Galilean cosmology. In each case, we present the relevant results in the form of tables for easy reference. Finally, we discuss briefly the higher order symmetries (the contact symmetries) and show how they are applied in the cases of scalar field cosmology and in the f(R) gravity.
    Electronic ISSN: 2073-8994
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  • 19
    Publication Date: 2018-06-29
    Description: Symmetry, Vol. 10, Pages 245: A Forecasting Model Based on Multi-Valued Neutrosophic Sets and Two-Factor, Third-Order Fuzzy Fluctuation Logical Relationships Symmetry doi: 10.3390/sym10070245 Authors: Hongjun Guan Jie He Aiwu Zhao Zongli Dai Shuang Guan Making predictions according to historical values has long been regarded as common practice by many researchers. However, forecasting solely based on historical values could lead to inevitable over-complexity and uncertainty due to the uncertainties inside, and the random influence outside, of the data. Consequently, finding the inherent rules and patterns of a time series by eliminating disturbances without losing important details has long been a research hotspot. In this paper, we propose a novel forecasting model based on multi-valued neutrosophic sets to find fluctuation rules and patterns of a time series. The contributions of the proposed model are: (1) using a multi-valued neutrosophic set (MVNS) to describe the fluctuation patterns of a time series, the model could represent the fluctuation trend of up, equal, and down with degrees of truth, indeterminacy, and falsity which significantly preserve details of the historical values; (2) measuring the similarities of different fluctuation patterns by the Hamming distance could avoid the confusion caused by incomplete information from limited samples; and (3) introducing another related time series as a secondary factor to avoid warp and deviation in inferring inherent rules of historical values, which could lead to more comprehensive rules for further forecasting. To evaluate the performance of the model, we explored the Taiwan Stock Exchange Capitalization Weighted Stock Index (TAIEX) as the major factor we forecast, and the Dow Jones Index as the secondary factor to facilitate the predicting of the TAIEX. To show the universality of the model, we applied the proposed model to forecast the Shanghai Stock Exchange Composite Index (SHSECI) as well.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 20
    Publication Date: 2018-06-29
    Description: Symmetry, Vol. 10, Pages 244: Computing Zagreb Indices and Zagreb Polynomials for Symmetrical Nanotubes Symmetry doi: 10.3390/sym10070244 Authors: Zehui Shao Muhammad Kamran Siddiqui Mehwish Hussain Muhammad Topological indices are numbers related to sub-atomic graphs to allow quantitative structure-movement/property/danger connections. These topological indices correspond to some specific physico-concoction properties such as breaking point, security, strain vitality of chemical compounds. The idea of topological indices were set up in compound graph hypothesis in view of vertex degrees. These indices are valuable in the investigation of mitigating exercises of specific Nanotubes and compound systems. In this paper, we discuss Zagreb types of indices and Zagreb polynomials for a few Nanotubes covered by cycles.
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  • 21
    Publication Date: 2018-08-01
    Description: Symmetry, Vol. 10, Pages 302: Fermion Scattering in a CPT-Even Lorentz Violation Quantum Electrodynamics Symmetry doi: 10.3390/sym10080302 Authors: Frederico Santos Manoel Ferreira In this work, we reassess two known processes of Quantum Electrodynamics involving electrons and muons. The photon propagator is modified by a CPT-even Lorentz-violating (LV) tensor, while fermion lines and the vertex interaction are not altered. Using the Feynman rules, the associated cross sections for unpolarized scatterings are evaluated, revealing the usual energy dependence and Lorentz-violating contributions that induce space anisotropy. A possible route to constraining the LV coefficients is presented and the results properly commented.
    Electronic ISSN: 2073-8994
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  • 22
    Publication Date: 2018-08-01
    Description: Symmetry, Vol. 10, Pages 301: Evaluating Water Use Efficiency in China’s Western Provinces Based on a Slacks-Based Measure (SBM)-Undesirable Window Model and a Malmquist Productivity Index Symmetry doi: 10.3390/sym10080301 Authors: Yuyan Luo Lu Yin Yong Qin Zhong Wang Yanfeng Gong This paper evaluated the water use efficiency in 12 Chinese western provinces from 2005 to 2015. Based on data availability and the index selection rationality and the slacks-based measure (SBM)-undesirable Window analysis model and the Malmquist productivity index, the water resource inputs and outputs were measured to analyze water use efficiency. Total investment in fixed assets for the whole society and total water, made up of total agricultural water, total industrial water, and total domestic water, were used as the input indexes, and regional GDP and waste water discharge were the output indexes, with the waste water discharge being regarded as an undesirable output. The data from different years and different provinces in the same period, and data from the same year and the same provinces in different periods were compared in order to derive the water resource efficiency and technical changes over time and space. It was found that the total water resource factor productivity in the 12 provinces grew slowly in the study period, that water resource technical progress positively affected water use efficiency, and that a lack of technical efficiency restricted water use efficiency growth. Several suggestions are given to optimize water use efficiency in the 12 provinces. The research findings and suggestions provide valuable reference for studies in related fields.
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  • 23
    Publication Date: 2018-08-02
    Description: Symmetry, Vol. 10, Pages 304: No-Reference Image Blur Assessment Based on Response Function of Singular Values Symmetry doi: 10.3390/sym10080304 Authors: Shanqing Zhang Pengcheng Li Xianghua Xu Li Li Ching-Chun Chang Blur is an important factor affecting the image quality. This paper presents an efficient no-reference (NR) image blur assessment method based on a response function of singular values. For an image, the grayscale image is computed to the acquire spatial information. In the meantime, the gradient map is computed to acquire the shape information, and the saliency map can be obtained by using scale-invariant feature transform (SIFT). Then, the grayscale image, the gradient map, and the saliency map are divided into blocks of the same size. The blocks of the gradient map are converted into discrete cosine transform (DCT) coefficients, from which the response function of singular values (RFSV) are generated. The sum of the RFSV are then utilized to characterize the image blur. The variance of the grayscale image and the DCT domain entropy of the gradient map are used to reduce the impact of the image content. The SIFT-dependent weights are calculated in the saliency map, which are assigned to the image blocks. Finally, the blur score is the normalized sum of the RFSV. Extensive experiments are conducted on four synthetic databases and two real blur databases. The experimental results indicate that the blur scores produced by our method are highly correlated with the subjective evaluations. Furthermore, the proposed method is superior to six state-of-the-art methods.
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  • 24
    Publication Date: 2018-08-08
    Description: Symmetry, Vol. 10, Pages 327: Different Forms of Triangular Neutrosophic Numbers, De-Neutrosophication Techniques, and their Applications Symmetry doi: 10.3390/sym10080327 Authors: Avishek Chakraborty Sankar Prasad Mondal Ali Ahmadian Norazak Senu Shariful Alam Soheil Salahshour In this paper, we introduce the concept of neutrosophic number from different viewpoints. We define different types of linear and non-linear generalized triangular neutrosophic numbers which are very important for uncertainty theory. We introduced the de-neutrosophication concept for neutrosophic number for triangular neutrosophic numbers. This concept helps us to convert a neutrosophic number into a crisp number. The concepts are followed by two application, namely in imprecise project evaluation review technique and route selection problem.
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  • 25
    Publication Date: 2018-08-09
    Description: Symmetry, Vol. 10, Pages 328: Thermodynamic Response of Beams on Winkler Foundation Irradiated by Moving Laser Pulses Symmetry doi: 10.3390/sym10080328 Authors: Yuxin Sun Shoubin Liu Zhangheng Rao Yuhang Li Jialing Yang In this paper, the exact analytical solutions are developed for the thermodynamic behavior of an Euler-Bernoulli beam resting on an elastic foundation and exposed to a time decaying laser pulse that scans over the beam with a uniform velocity. The governing equations, namely the heat conduction equation and the vibration equation are solved using the Green’s function approach. The temporal and special distributions of temperature, deflection, strain, and the energy absorbed by the elastic foundation are calculated. The effects of the laser motion speed, the modulus of elastic foundation reaction, and the laser pulse duration time are studied in detail.
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  • 26
    Publication Date: 2018-08-10
    Description: Symmetry, Vol. 10, Pages 331: Applications of Neutrosophic Bipolar Fuzzy Sets in HOPE Foundation for Planning to Build a Children Hospital with Different Types of Similarity Measures Symmetry doi: 10.3390/sym10080331 Authors: Raja Muhammad Hashim Muhammad Gulistan Florentin Smarandache In this paper we provide an application of neutrosophic bipolar fuzzy sets in daily life’s problem related with HOPE foundation that is planning to build a children hospital, which is the main theme of this paper. For it we first develop the theory of neutrosophic bipolar fuzzy sets which is a generalization of bipolar fuzzy sets. After giving the definition we introduce some basic operation of neutrosophic bipolar fuzzy sets and focus on weighted aggregation operators in terms of neutrosophic bipolar fuzzy sets. We define neutrosophic bipolar fuzzy weighted averaging ( N B FWA ) and neutrosophic bipolar fuzzy ordered weighted averaging ( N B FOWA ) operators. Next we introduce different kinds of similarity measures of neutrosophic bipolar fuzzy sets. Finally as an application we give an algorithm for the multiple attribute decision making problems under the neutrosophic bipolar fuzzy environment by using the different kinds of neutrosophic bipolar fuzzy weighted/fuzzy ordered weighted aggregation operators with a numerical example related with HOPE foundation.
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  • 27
    Publication Date: 2018-08-10
    Description: Symmetry, Vol. 10, Pages 332: On the Distinguishing Number of Functigraphs Symmetry doi: 10.3390/sym10080332 Authors: Muhammad Fazil Muhammad Murtaza Zafar Ullah Usman Ali Imran Javaid Let G 1 and G 2 be disjoint copies of a graph G and g : V ( G 1 ) → V ( G 2 ) be a function. A functigraph F G consists of the vertex set V ( G 1 ) ∪ V ( G 2 ) and the edge set E ( G 1 ) ∪ E ( G 2 ) ∪ { u v : g ( u ) = v } . In this paper, we extend the study of distinguishing numbers of a graph to its functigraph. We discuss the behavior of distinguishing number in passing from G to F G and find its sharp lower and upper bounds. We also discuss the distinguishing number of functigraphs of complete graphs and join graphs.
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  • 28
    Publication Date: 2018-08-11
    Description: Symmetry, Vol. 10, Pages 333: A Multi-Level Privacy-Preserving Approach to Hierarchical Data Based on Fuzzy Set Theory Symmetry doi: 10.3390/sym10080333 Authors: Jinyan Wang Guoqing Cai Chen Liu Jingli Wu Xianxian Li Nowadays, more and more applications are dependent on storage and management of semi-structured information. For scientific research and knowledge-based decision-making, such data often needs to be published, e.g., medical data is released to implement a computer-assisted clinical decision support system. Since this data contains individuals’ privacy, they must be appropriately anonymized before to be released. However, the existing anonymization method based on l-diversity for hierarchical data may cause a serious similarity attack, and cannot protect data privacy very well. In this paper, we utilize fuzzy sets to divide levels for sensitive numerical and categorical attribute values uniformly (a categorical attribute value can be converted into a numerical attribute value according to its frequency of occurrences), and then transform the value levels to sensitivity levels. The privacy model ( α l e v h , k)-anonymity for hierarchical data with multi-level sensitivity is proposed. Furthermore, we design a privacy-preserving approach to achieve this privacy model. Experiment results demonstrate that our approach is obviously superior to existing anonymous approach in hierarchical data in terms of utility and security.
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  • 29
    Publication Date: 2018-08-12
    Description: Symmetry, Vol. 10, Pages 335: Finite Element Study of a Threaded Fastening: The Case of Surgical Screws in Bone Symmetry doi: 10.3390/sym10080335 Authors: J. A. López-Campos A. Segade E. Casarejos J. R. Fernández J. A. Vilán P. Izquierdo This paper studies the stress state of a threaded fastening by using Finite Element (FE) models, applied to surgical screws in cortical bone. There is a general interest in studying the stress states induced in the different elements of a joint caused by the thread contact. Analytical models were an initial approach, and later FE models allowed detailed studies of the complex phenomena related to these joints. Different studies have evaluated standard threaded joints in machinery and structures, being the thread symmetric. However, surgical screws employ asymmetric thread geometry, selected to improve the stress level generated in the bone. Despite the interest and widespread use, there is scarce documentation on the actual effect of this thread type. In this work, we discuss the results provided by FE models with detailed descriptions of the contacts comparing differences caused by the materials of the joint, the thread geometry and the thread’s three-dimensional helical effects. The complex contacts at the threaded surfaces cause intense demand on computational resources that often limits the studies including these joints. We analyze the results provided by one commercial software package to simplify the threaded joints. The comparison with detailed FE models allows a definition of the level of uncertainty and possible limitations of this type of simplifications, and helps in making suitable choices for complex applications.
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  • 30
    Publication Date: 2018-08-14
    Description: Symmetry, Vol. 10, Pages 339: A Three-Dimensional Constrained Ordered Weighted Averaging Aggregation Problem with Lower Bounded Variables Symmetry doi: 10.3390/sym10080339 Authors: Yi-Fang Chen Hui-Chin Tang We consider the constrained ordered weighted averaging (OWA) aggregation problem with a single constraint and lower bounded variables. For the three-dimensional constrained OWA aggregation problem with lower bounded variables, we present four types of solution(x1',x2',x3') depending on the number of zero elements. According to the computerized experiment we perform, the lower bounds can affect the solution(x1',x2',x3') types, thereby affecting the optimal solution of the three-dimensional constrained OWA aggregation problem with lower bounded variables.
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  • 31
    Publication Date: 2018-08-20
    Description: Symmetry, Vol. 10, Pages 349: Optimizing the High-Level Maintenance Planning Problem of the Electric Multiple Unit Train Using a Modified Particle Swarm Optimization Algorithm Symmetry doi: 10.3390/sym10080349 Authors: Jianping Wu Boliang Lin Hui Wang Xuhui Zhang Zhongkai Wang Jiaxi Wang Electric multiple unit (EMU) trains’ high-level maintenance planning is a discrete problem in mathematics. The high-level maintenance process of the EMU trains consumes plenty of time. When the process is undertaken during peak periods of the passenger flow, the transportation demand may not be fully satisfied due to the insufficient supply of trains. In contrast, if the process is undergone in advance, extra costs will be incurred. Based on the practical requirements of high-level maintenance, a 0–1 programming model is proposed. To simplify the description of the model, candidate sets of delivery dates, i.e., time windows, are generated according to the historical data and maintenance regulations. The constraints of the model include maintenance regulations, the passenger transportation demand, and capacities of workshop. The objective function is to minimize the mileage losses of all EMU trains. Moreover, a modified particle swarm algorithm is developed for solving the problem. Finally, a real-world case study of Shanghai Railway is conducted to demonstrate the proposed method. Computational results indicate that the (approximate) optimal solution can be obtained successfully by our method and the proposed method significantly reduces the solution time to 500 s.
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  • 32
    Publication Date: 2018-08-19
    Description: Symmetry, Vol. 10, Pages 348: Sharp Bounds on the Higher Order Schwarzian Derivatives for Janowski Classes Symmetry doi: 10.3390/sym10080348 Authors: Nak Eun Cho Virendra Kumar V. Ravichandran Higher order Schwarzian derivatives for normalized univalent functions were first considered by Schippers, and those of convex functions were considered by Dorff and Szynal. In the present investigation, higher order Schwarzian derivatives for the Janowski star-like and convex functions are considered, and sharp bounds for the first three consecutive derivatives are investigated. The results obtained in this paper generalize several existing results in this direction.
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  • 33
    Publication Date: 2018-08-18
    Description: Symmetry, Vol. 10, Pages 345: Neutrosophic Duplets of {Zpn,×} and {Zpq,×} and Their Properties Symmetry doi: 10.3390/sym10080345 Authors: Vasantha Kandasamy W.B. Ilanthenral Kandasamy Florentin Smarandache The notions of neutrosophy, neutrosophic algebraic structures, neutrosophic duplet and neutrosophic triplet were introduced by Florentin Smarandache. In this paper, the neutrosophic duplets of Z p n , Z p q and Z p 1 p 2 … p n are studied. In the case of Z p n and Z p q , the complete characterization of neutrosophic duplets are given. In the case of Z p 1 … p n , only the neutrosophic duplets associated with p i s are provided; i = 1 , 2 , … , n . Some open problems related to neutrosophic duplets are proposed.
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  • 34
    Publication Date: 2018-08-26
    Description: Symmetry, Vol. 10, Pages 361: Porous Scaffold Design Based on Minimal Surfaces: Development and Assessment of Variable Architectures Symmetry doi: 10.3390/sym10090361 Authors: Rita Ambu Anna Eva Morabito In tissue engineering, biocompatible porous scaffolds that try to mimic the features and function of the bone are of great relevance. In this paper, an effective method for the design of 3D porous scaffolds is applied to the modelling of structures with variable architectures. These structures are of interest since they are more similar to the stochastic configuration of real bone with respect to architectures made of a unit cell replicated in three orthogonal directions, which are usually considered for this kind of applications. This property configures them as, potentially, more suitable to satisfy simultaneously the biological requirements and those relative to the mechanical strength. The procedure implemented is based on the implicit surface modelling method and the use of a triply periodic minimal surface (TPMS), specifically, the Schwarz’s Primitive (P) minimal surface, whose geometry was considered for the development of scaffolds with different configurations. The representative structures modelled were numerically analysed by means of finite element analysis (FEA), considering them made of a biocompatible titanium alloy. The architectures considered were thus assessed in terms of the relationship between the geometrical configuration and the mechanical response to compression loading.
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  • 35
    Publication Date: 2018-08-28
    Description: Symmetry, Vol. 10, Pages 366: The (A)symmetry between the Exterior and Interior of a Schwarzschild Black Hole Symmetry doi: 10.3390/sym10090366 Authors: Pawel Gusin Andy Augousti Filip Formalik Andrzej Radosz A black hole in a Schwarzschild spacetime is considered. A transformation is proposed that describes the relationship between the coordinate systems exterior and interior to an event horizon. The application of this transformation permits considerations of the (a)symmetry of a range of phenomena taking place on both sides of the event horizon. The paper investigates two distinct problems of a uniformly accelerated particle. In one of these, although the equations of motion are the same in the regions on both sides, the solutions turn out to be very different. This manifests the differences of the properties of these two ranges.
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  • 36
    Publication Date: 2018-08-28
    Description: Symmetry, Vol. 10, Pages 365: On Connection between Second-Degree Exterior and Symmetric Derivations of Kähler Modules Symmetry doi: 10.3390/sym10090365 Authors: Hamiyet Merkepçi Mathematical physics looks for ways to apply mathematical ideas to problems in physics. In differential forms, the tensor form is first defined, and the definitions of exterior and symmetric differential forms are made accordingly. For instance, M is an R-module, M ⊗ R M the tensor product of M with itself and H a submodule of M ⊗ R M generated by x ⊗ y − y ⊗ x , where x , y in M. Then, ∨ 2 ( M ) = M ⊗ R M / H is called the second symmetric power of M. A role of the exterior differential forms in field theory is related to the conservation laws for physical fields, etc. In this study, I present a new approach to emphasize the properties of second exterior and symmetric derivations on Kahler modules, and I find a connection between them. I constitute exact sequences of ∨ 2 ( Ω 1 ( S ) ) and Λ 2 ( Ω 1 ( S ) ) , and I describe and prove a new isomorphism in the following: Let S be an affine algebra presented by R / I , where R = k [ x 1 , … x s ] is a polynomial algebra and I = ( f 1 , … f m ) an ideal of R. Then, I have J 1 Ω 1 ( S ) ≃ Ω 1 ( S ) ⊕ ∨ 2 ( Ω 1 ( S ) ) ⊕ Λ 2 ( Ω 1 ( S ) .
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  • 37
    Publication Date: 2018-09-01
    Description: Symmetry, Vol. 10, Pages 369: A Comprehensive Comparative Analysis of the Basic Theory of the Short Term Bus Passenger Flow Prediction Symmetry doi: 10.3390/sym10090369 Authors: Huawei Zhai Licheng Cui Yu Nie Xiaowei Xu Weishi Zhang In order to meet the real-time public travel demands, the bus operators need to adjust the timetables in time. Therefore, it is necessary to predict the variations of the short-term passenger flow. Under the help of the advanced public transportation systems, a large amount of real-time data about passenger flow is collected from the automatic passenger counters, automatic fare collection systems, etc. Using these data, different kinds of methods are proposed to predict future variations of the short-term bus passenger flow. Based on the properties and background knowledge, these methods are classified into three categories: linear, nonlinear and combined methods. Their performances are evaluated in detail in the major aspects of the prediction accuracy, the complexity of training data structure and modeling process. For comparison, some long-term prediction methods are also analyzed simply. At last, it points that, with the help of automatic technology, a large amount of data about passenger flow will be collected, and using the big data technology to speed up the data preprocessing and modeling process may be one of the directions worthy of study in the future.
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  • 38
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 372: Decaying Dark Energy in Light of the Latest Cosmological Dataset Symmetry doi: 10.3390/sym10090372 Authors: Ivan de Martino Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature–redshift scaling relation. We use the most recent observationally-determined datasets, including Supernovae Type Ia and Gamma Ray Bursts data, along with H ( z ) and Cosmic Microwave Background temperature versus z data and the reduced Cosmic Microwave Background parameters, to improve the previous constraints on these models. We perform a Monte Carlo Markov Chain analysis to constrain the parameter space, on the basis of two distinct methods. In view of the first method, the Hubble constant and the matter density are left to vary freely. In this case, our results are compatible with previous analyses associated with decaying Dark Energy models, as well as with the most recent description of the cosmological background. In view of the second method, we set the Hubble constant and the matter density to their best fit values obtained by the Planck satellite, reducing the parameter space to two dimensions, and improving the existent constraints on the model’s parameters. Our results suggest that the accelerated expansion of the Universe is well described by the cosmological constant, and we argue that forthcoming observations will play a determinant role to constrain/rule out decaying Dark Energy.
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  • 39
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 370: Multimedia Data Modelling Using Multidimensional Recurrent Neural Networks Symmetry doi: 10.3390/sym10090370 Authors: Zhen He Shaobing Gao Liang Xiao Daxue Liu Hangen He Modelling the multimedia data such as text, images, or videos usually involves the analysis, prediction, or reconstruction of them. The recurrent neural network (RNN) is a powerful machine learning approach to modelling these data in a recursive way. As a variant, the long short-term memory (LSTM) extends the RNN with the ability to remember information for longer. Whilst one can increase the capacity of LSTM by widening or adding layers, additional parameters and runtime are usually required, which could make learning harder. We therefore propose a Tensor LSTM where the hidden states are tensorised as multidimensional arrays (tensors) and updated through a cross-layer convolution. As parameters are spatially shared within the tensor, we can efficiently widen the model without extra parameters by increasing the tensorised size; as deep computations of each time step are absorbed by temporal computations of the time series, we can implicitly deepen the model with little extra runtime by delaying the output. We show by experiments that our model is well-suited for various multimedia data modelling tasks, including text generation, text calculation, image classification, and video prediction.
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  • 40
    Publication Date: 2018-09-06
    Description: Symmetry, Vol. 10, Pages 384: A New Evaluation for Solving the Fully Fuzzy Data Envelopment Analysis with Z-Numbers Symmetry doi: 10.3390/sym10090384 Authors: Ali Namakin Seyyed Esmaeil Najafi Mohammad Fallah Mehrdad Javadi There are numerous models for solving the efficiency evaluation in data envelopment analysis (DEA) with fuzzy input and output data. However, because of the limitation of those strategies, they cannot be implemented for solving fully fuzzy DEA (FFDEA). Furthermore, in real-world problems with imprecise data, fuzziness is not sufficient to consider, and the reliability of the information is also very vital. To overcome these flaws, this paper presented a new method for solving the fully fuzzy DEA model where all parameters are Z-numbers. The new approach is primarily based on crisp linear programming and has a simple structure. Moreover, it is proved that the only existing method to solve FFDEA with Z-numbers is not valid. An example is also presented to illustrate the efficiency of our proposed method and provide an explanation for the content of the paper.
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  • 41
    Publication Date: 2018-09-05
    Description: Symmetry, Vol. 10, Pages 380: The Weighted Arithmetic Mean–Geometric Mean Inequality is Equivalent to the Hölder Inequality Symmetry doi: 10.3390/sym10090380 Authors: Yongtao Li Xian-Ming Gu Jianxing Zhao In the current note, we investigate the mathematical relations among the weighted arithmetic mean–geometric mean (AM–GM) inequality, the Hölder inequality and the weighted power-mean inequality. Meanwhile, the proofs of mathematical equivalence among the weighted AM–GM inequality, the weighted power-mean inequality and the Hölder inequality are fully achieved. The new results are more generalized than those of previous studies.
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  • 42
    Publication Date: 2018-09-05
    Description: Symmetry, Vol. 10, Pages 381: Time-Dependent Behavior of a Circular Symmetrical Tunnel Supported with Rockbolts Symmetry doi: 10.3390/sym10090381 Authors: Wei Han Gang Wang Chuanzheng Liu Hengjie Luan Ke Wang Under the effect of initial stress and excavation disturbance, there exists interaction between rock mass and rockbolt in deeply buried tunnels. In order to fully explore the mechanism of rock mass supported with rockbolts, this article studied the time-dependent behavior of the rock mass supported with discretely mechanically or frictionally coupled (DMFC) rockbolts. The interaction model elastic solutions under distributed force model were analyzed, then the viscoelastic analytical solutions were conducted to describe the rheological properties of the coupling model, and the solutions were acquired by setting the constitutive models of the rockbolt and rock mass in terms of a one-dimensional Kelvin model and a three-dimensional Burgers model based on material properties and dimension. Several examples were performed and the influence of initial stress σ0, the viscosity parameters η1 and η2 of the three-dimensional Burgers model as well as the pre-tension T0 on reinforcement effect were analyzed. According to the proposed model, the smaller η2 is or the larger the pre-tension T0 is, the more effective the support effect. However, when the pre-tension is too large, the support effect is no longer significantly enhanced. In addition, the early reinforcement effect is controlled by the first creep stage in the Burgers model while the ultimate support effect is mainly influenced by the viscosity coefficient of the second creep stage in the Burgers model. This research can provide an important theoretical reference to guide the parameter design of rockbolt reinforcement engineering in a circular symmetrical tunnel.
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  • 43
    Publication Date: 2018-09-11
    Description: Symmetry, Vol. 10, Pages 391: Modeling the Service Network Design Problem in Railway Express Shipment Delivery Symmetry doi: 10.3390/sym10090391 Authors: Siqi Liu Boliang Lin Jianping Wu Yinan Zhao As air pollution becomes increasingly severe, express trains play a more important role in shifting road freight and reducing carbon emissions. Thus, the design of railway express shipment service networks has become a key issue, which needs to be addressed urgently both in theory and practice. The railway express shipment service network design problem (RESSNDP) not only involves the selection of train services and determination of service frequency, but it is also associated with shipment routing, which can be viewed as a service network design problem (SNDP) with railway characteristics. This paper proposes a non-linear integer programming model (INLP) which aims at finding a service network and shipment routing plan with minimum cost while satisfying the transportation time constraints of shipments, carrying capacity constraints of train services, flow conservation constraint and logical constraints among decision variables. In addition, a linearization technique was adopted to transform our model into a linear one to obtain a global optimal solution. To evaluate the effectiveness and efficiency of our approach, a small trial problem was solved by the state-of-the-art mathematical programming solver Gurobi 7.5.2.
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  • 44
    Publication Date: 2018-09-11
    Description: Symmetry, Vol. 10, Pages 392: Probabilistic Hesitant Intuitionistic Linguistic Term Sets in Multi-Attribute Group Decision Making Symmetry doi: 10.3390/sym10090392 Authors: M. G. Abbas Malik Zia Bashir Tabasam Rashid Jawad Ali Decision making is the key component of people’s daily life, from choosing a mobile phone to engaging in a war. To model the real world more accurately, probabilistic linguistic term sets (PLTSs) were proposed to manage a situation in which several possible linguistic terms along their corresponding probabilities are considered at the same time. Previously, in linguistic term sets, the probabilities of all linguistic term sets are considered to be equal which is unrealistic. In the process of decision making, due to the vagueness and complexity of real life, an expert usually hesitates and unable to express its opinion in a single term, thus making it difficult to reach a final agreement. To handle real life scenarios of a more complex nature, only membership linguistic decision making is unfruitful; thus, some mechanism is needed to express non-membership linguistic term set to deal with imprecise and uncertain information in more efficient manner. In this article, a novel notion called probabilistic hesitant intuitionistic linguistic term set (PHILTS) is designed, which is composed of membership PLTSs and non-membership PLTSs describing the opinions of decision makers (DMs). In the theme of PHILTS, the probabilities of membership linguistic terms and non-membership linguistic terms are considered to be independent. Then, basic operations, some governing operational laws, the aggregation operators, normalization process and comparison method are studied for PHILTSs. Thereafter, two practical decision making models: aggregation based model and the extended TOPSIS model for PHILTS are designed to classify the alternatives from the best to worst, as an application of PHILTS to multi-attribute group decision making. In the end, a practical problem of real life about the selection of the best alternative is solved to illustrate the applicability and effectiveness of our proposed set and models.
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  • 45
    Publication Date: 2018-09-10
    Description: Symmetry, Vol. 10, Pages 390: Social Risk Dissociates Social Network Structure across Lateralized Behaviors in Spider Monkeys Symmetry doi: 10.3390/sym10090390 Authors: Emily R. Boeving Eliza L. Nelson Reports of lateralized behavior are widespread, although the majority of findings have focused on the visual or motor domains. Less is known about laterality with regards to the social domain. We previously observed a left-side bias in two social affiliative behaviors—embrace and face-embrace—in captive Colombian spider monkeys (Ateles fusciceps rufiventris). Here we applied social network analysis to laterality for the first time. Our findings suggest that laterality influences social structure in spider monkeys with structural differences between networks based on direction of behavioral bias and social interaction type. We attribute these network differences to a graded spectrum of social risk comprised of three dimensions.
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  • 46
    Publication Date: 2018-09-15
    Description: Symmetry, Vol. 10, Pages 399: Cryptanalysis and Improvement on an Image Encryption Algorithm Design Using a Novel Chaos Based S-Box Symmetry doi: 10.3390/sym10090399 Authors: Congxu Zhu Guojun Wang Kehui Sun This article performs the cryptanalysis of an image encryption algorithm using an S-box generated by chaos. The algorithm has the advantages of simple structure, high encryption efficiency, and good encryption performance. However, an attentive investigation reveals that it has some undiscovered security flaws. The image cryptosystem is totally breakable under proposed chosen-plaintext attack, and only two chosen plain-images are required. An array equivalent to the S-box is constructed by an elaborately designed chosen-plaintext image, and the cipher-image is deciphered without having to know the S-box itself. Both mathematical deduction and experimental results validate the feasibility of the attacking scheme. Furthermore, an improved encryption scheme is proposed, in which a feedback mechanism is introduced, a bidirectional diffusion scheme is designed, and values of the ciphertext are associated with more parameters in each diffusion process. Testing results and security analysis verify that the improved cryptographic system can achieve a higher security level and has a better performance than some of the latest encryption algorithms.
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  • 47
    Publication Date: 2018-09-15
    Description: Symmetry, Vol. 10, Pages 400: Change of Blink Rate in Viewing Virtual Reality with HMD Symmetry doi: 10.3390/sym10090400 Authors: Jungho Kim Yadav Sunil Kumar Jisang Yoo Soonchul Kwon The eye blink rate, a major human physiological response, directly affects ocular diseases, such as keratitis and dry eye syndrome. It has been shown that the eye blink rate in normal eyes has a certain frequency for individuals, from 6–30 times/min. It was suggested in a previous study that the eye blink rate can be decreased during the viewing of high-intensity and realistic content. Therefore, in this paper, we examine the change of the eye blink rate during the HMD (head-mounted display) viewing of VR (virtual reality) contents; accordingly, we propose an algorithm to measure the eye blink rate as well as compare and analyze this rate in three different environments (natural, monitor, and HMD). We confirmed that IPD (interpupillary distance) and phoria affected the eye blink rate in each environment. In this experiment, 21 subjects (28.38 ± 6.87 years) were selected, and a paired t-test was performed for changes in the eye blink rate over 1 min for each environment. The IPD and phoria effects on the eye blink rate were confirmed using the Spearman’s correlation coefficient. In this experiment, the eye blink rate was decreased in the monitor and HMD environments compared with the natural environment, while that in the HMD environment was decreased compared with the monitor environment. The results of the correlation analysis of far IPD and the eye blink rate show no statistical significance or correlation. The correlation analysis of near IPD and the eye blink rate showed a strong positive correlation of the eye blink rate in the monitor environment. The correlation analysis of distance phoria and the eye blink rate showed a strong negative correlation of the eye blink rate in the HMD environment. The correlation analysis of near-field phoria and the eye blink rate showed a strong negative correlation of the eye blink rate in the HMD environment. It is expected that the results of this study will be used as a VR-viewing recommendation.
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  • 48
    Publication Date: 2018-09-15
    Description: Symmetry, Vol. 10, Pages 401: Symmetric Triangular Interval Type-2 Intuitionistic Fuzzy Sets with Their Applications in Multi Criteria Decision Making Symmetry doi: 10.3390/sym10090401 Authors: Sukhveer Singh Harish Garg Type-2 intuitionistic fuzzy set (T2IFS) is a powerful and important extension of the classical fuzzy set, intuitionistic fuzzy set to measure the vagueness and uncertainty. In a practical decision-making process, there always occurs an inter-relationship among the multi-input arguments. To deal with this point, the motivation of the present paper is to develop some new interval type-2 (IT2) intuitionistic fuzzy aggregation operators which can consider the multi interaction between the input argument. To achieve it, we define a symmetric triangular interval T2IFS (TIT2IFS), its operations, Hamy mean (HM) operator to aggregate the preference of the symmetric TIT2IFS and then shows its applicability through a multi-criteria decision making (MCDM). Several enviable properties and particular cases together with following different parameter values of this operator are calculated in detail. At last a numerical illustration is to given to exemplify the practicability of the proposed technique and a comparative analysis is analyzed in detail.
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  • 49
    Publication Date: 2018-09-18
    Description: Symmetry, Vol. 10, Pages 406: Limits of it-Soft Sets and Their Applications for Rough Sets Symmetry doi: 10.3390/sym10090406 Authors: Xiaoliang Xie Jiali He Soft set theory is a mathematical tool for handling uncertainty. This paper investigates the limits of the interval type of soft sets ( i t -soft sets). The notion of i t -soft sets is first introduced. Then, the limits of i t -soft sets are proposed and their properties obtained. Next, point-wise continuity of i t -soft sets and continuous i t -soft sets is discussed. Finally, an application for rough sets is given.
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  • 50
    Publication Date: 2018-09-18
    Description: Symmetry, Vol. 10, Pages 407: Vertex Labeling and Routing for Farey-Type Symmetrically-Structured Graphs Symmetry doi: 10.3390/sym10090407 Authors: Wenchao Jiang Yinhu Zhai Zhigang Zhuang Paul Martin Zhiming Zhao Jia-Bao Liu The generalization of Farey graphs and extended Farey graphs all originate from Farey graphs. They are simultaneously scale-free and small-world. A labeling of the vertices for them are proposed here. All of the shortest paths between any two vertices in these two graphs can be determined only on their labels. The number of shortest paths between any two vertices is the product of two Fibonacci numbers; it is increasing almost linearly with the order or size of the graphs. However, the label-based routing algorithm runs in logarithmic time O(logn). Our efficient routing protocol for Farey-type models should help contribute toward the understanding of several physical dynamic processes.
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  • 51
    Publication Date: 2018-09-18
    Description: Symmetry, Vol. 10, Pages 405: Fixed Points Results in Algebras of Split Quaternion and Octonion Symmetry doi: 10.3390/sym10090405 Authors: Mobeen Munir Asim Naseem Akhtar Rasool Muhammad Shoaib Saleem Shin Min Kang Fixed points of functions have applications in game theory, mathematics, physics, economics and computer science. The purpose of this article is to compute fixed points of a general quadratic polynomial in finite algebras of split quaternion and octonion over prime fields Z p. Some characterizations of fixed points in terms of the coefficients of these polynomials are also given. Particularly, cardinalities of these fixed points have been determined depending upon the characteristics of the underlying field.
    Electronic ISSN: 2073-8994
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  • 52
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 419: Probabilistic Single-Valued (Interval) Neutrosophic Hesitant Fuzzy Set and Its Application in Multi-Attribute Decision Making Symmetry doi: 10.3390/sym10090419 Authors: Songtao Shao Xiaohong Zhang Yu Li Chunxin Bo The uncertainty and concurrence of randomness are considered when many practical problems are dealt with. To describe the aleatory uncertainty and imprecision in a neutrosophic environment and prevent the obliteration of more data, the concept of the probabilistic single-valued (interval) neutrosophic hesitant fuzzy set is introduced. By definition, we know that the probabilistic single-valued neutrosophic hesitant fuzzy set (PSVNHFS) is a special case of the probabilistic interval neutrosophic hesitant fuzzy set (PINHFS). PSVNHFSs can satisfy all the properties of PINHFSs. An example is given to illustrate that PINHFS compared to PSVNHFS is more general. Then, PINHFS is the main research object. The basic operational relations of PINHFS are studied, and the comparison method of probabilistic interval neutrosophic hesitant fuzzy numbers (PINHFNs) is proposed. Then, the probabilistic interval neutrosophic hesitant fuzzy weighted averaging (PINHFWA) and the probability interval neutrosophic hesitant fuzzy weighted geometric (PINHFWG) operators are presented. Some basic properties are investigated. Next, based on the PINHFWA and PINHFWG operators, a decision-making method under a probabilistic interval neutrosophic hesitant fuzzy circumstance is established. Finally, we apply this method to the issue of investment options. The validity and application of the new approach is demonstrated.
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  • 53
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 418: Four Operators of Rough Sets Generalized to Matroids and a Matroidal Method for Attribute Reduction Symmetry doi: 10.3390/sym10090418 Authors: Jingqian Wang Xiaohong Zhang Rough sets provide a useful tool for data preprocessing during data mining. However, many algorithms related to some problems in rough sets, such as attribute reduction, are greedy ones. Matroids propose a good platform for greedy algorithms. Therefore, it is important to study the combination between rough sets and matroids. In this paper, we investigate rough sets and matroids through their operators, and provide a matroidal method for attribute reduction in information systems. Firstly, we generalize four operators of rough sets to four operators of matroids through the interior, closure, exterior and boundary axioms, respectively. Thus, there are four matroids induced by these four operators of rough sets. Then, we find that these four matroids are the same one, which implies the relationship about operators between rough sets and matroids. Secondly, a relationship about operations between matroids and rough sets is presented according to the induced matroid. Finally, the girth function of matroids is used to compute attribute reduction in information systems.
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  • 54
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 417: Some Results on Multigranulation Neutrosophic Rough Sets on a Single Domain Symmetry doi: 10.3390/sym10090417 Authors: Hu Zhao Hong-Ying Zhang As a generalization of single value neutrosophic rough sets, the concept of multi-granulation neutrosophic rough sets was proposed by Bo et al., and some basic properties of the pessimistic (optimistic) multigranulation neutrosophic rough approximation operators were studied. However, they did not do a comprehensive study on the algebraic structure of the pessimistic (optimistic) multigranulation neutrosophic rough approximation operators. In the present paper, we will provide the lattice structure of the pessimistic multigranulation neutrosophic rough approximation operators. In particular, in the one-dimensional case, for special neutrosophic relations, the completely lattice isomorphic relationship between upper neutrosophic rough approximation operators and lower neutrosophic rough approximation operators is proved.
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  • 55
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 416: Intrasession Reliability of the Tests to Determine Lateral Asymmetry and Performance in Volleyball Players Symmetry doi: 10.3390/sym10090416 Authors: Mario Iglesias-Caamaño Javier Carballo-López Tania Álvarez-Yates Alba Cuba-Dorado Oscar García-García The development of lateral asymmetries in athletes could have an influence on performance or injuries. The aim of this study was to determine the within-day reliability of the symmetry tests and the performance tests, and explore the relationship between them. Eighteen male volleyball players (18.1 ± 2.1 years) participated in this study. Seven lateral symmetry assessments were used, namely: lateral symmetry through tensiomyography (LS), active knee extension (AKE), Y-balance test (YBT), muscular electrical activity in attack jump (MEA-AJ), single-leg squat jump (SLSJ), triple hop test for distance (THTD), and bilateral maximum repetition in leg press (1RMSL); and three volleyball performance tests, namely: the T-test, counter-movement jump (CMJ), and attack jump (AJ). Three in-day measurements were taken from each volleyball player after the recovery was completed. The reliability was calculated through the intraclass correlation coefficient and the coefficient of variation, and the relationship was calculated through Pearson’s bivariate correlation coefficient (p < 0.05). The results indicate that AKE, YBT, and LS are the symmetry tests with increased reproducibility. THTD correlates positively with the AKE test and 1RMSL test, and a greater symmetry in the YBT correlates with a greater performance in the CMJ and AJ performance tests. In conclusion, AKE, LS, and YBT are the best tests to determine, with reliability, the asymmetries in volleyball players, and a greater symmetry in the YBT seems to influence the height of bilateral vertical jump.
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  • 56
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 415: Ground State Representations of Some Non-Rational Conformal Nets Symmetry doi: 10.3390/sym10090415 Authors: Yoh Tanimoto We construct families of ground state representations of the U ( 1 ) -current net and of the Virasoro nets Vir c with central charge c ≥ 1 . We show that these representations are not covariant with respect to the original dilations, and those on the U ( 1 ) -current net are not solitonic. Furthermore, by going to the dual net with respect to the ground state representations of Vir c , one obtains possibly new family of Möbius covariant nets on S 1 .
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  • 57
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 413: On Fitting Ideals of Kahler Differential Module Symmetry doi: 10.3390/sym10090413 Authors: Nurbige Turan Necati Olgun Let k be an algebraically closed field of characteristic zero, and R / I and S / J be algebras over k . Ω 1 ( R / I ) and Ω 1 ( S / J ) denote universal module of first order derivation over k . The main result of this paper asserts that the first nonzero Fitting ideal Ω 1 ( R / I ⊗ k S / J ) is an invertible ideal, if the first nonzero Fitting ideals Ω 1 ( R / I ) and Ω 1 ( S / J ) are invertible ideals. Then using this result, we conclude that the projective dimension of Ω 1 ( R / I ⊗ k S / J ) is less than or equal to one.
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  • 58
    Publication Date: 2018-09-20
    Description: Symmetry, Vol. 10, Pages 414: Emotion Classification Using a Tensorflow Generative Adversarial Network Implementation Symmetry doi: 10.3390/sym10090414 Authors: Traian Caramihale Dan Popescu Loretta Ichim The detection of human emotions has applicability in various domains such as assisted living, health monitoring, domestic appliance control, crowd behavior tracking real time, and emotional security. The paper proposes a new system for emotion classification based on a generative adversarial network (GAN) classifier. The generative adversarial networks have been widely used for generating realistic images, but the classification capabilities have been vaguely exploited. One of the main advantages is that by using the generator, we can extend our testing dataset and add more variety to each of the seven emotion classes we try to identify. Thus, the novelty of our study consists in increasing the number of classes from N to 2N (in the learning phase) by considering real and fake emotions. Facial key points are obtained from real and generated facial images, and vectors connecting them with the facial center of gravity are used by the discriminator to classify the image as one of the 14 classes of interest (real and fake for seven emotions). As another contribution, real images from different emotional classes are used in the generation process unlike the classical GAN approach which generates images from simple noise arrays. By using the proposed method, our system can classify emotions in facial images regardless of gender, race, ethnicity, age and face rotation. An accuracy of 75.2% was obtained on 7000 real images (14,000, also considering the generated images) from multiple combined facial datasets.
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  • 59
    Publication Date: 2018-09-19
    Description: Symmetry, Vol. 10, Pages 412: Modeling and Control for a Multi-Rope Parallel Suspension Lifting System under Spatial Distributed Tensions and Multiple Constraints Symmetry doi: 10.3390/sym10090412 Authors: Naige Wang Guohua Cao Lu Yan Lei Wang The modeling and control of the multi-rope parallel suspension lifting system (MPSLS) are investigated in the presence of different and spatial distributed tensions; unknown boundary disturbances; and multiple constraints, including time varying geometric constraint, input saturation, and output constraint. To describe the system dynamics more accurately, the MPSLS is modelled by a set of partial differential equations and ordinary differential equations (PDEs-ODEs) with multiple constraints, which is a nonhomogeneous and coupled PDEs-ODEs, and makes its control more difficult. Adaptive boundary control is a recommended method for position regulation and vibration degradation of the MPSLS, where adaptation laws and a boundary disturbance observer are formulated to handle system uncertainties. The system stability is rigorously proved by using Lyapunov’s direct method, and the position and vibration eventually diminish to a bounded neighborhood of origin. The original PDEs-ODEs are solved by finite difference method, and the multiple constraints problem is processed simultaneously. Finally, the performance of the proposed control is demonstrated by both the results of ADAMS simulation and numerical calculation.
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  • 60
    Publication Date: 2018-09-19
    Description: Symmetry, Vol. 10, Pages 411: Dark Energy and Dark Matter Interaction: Kernels of Volterra Type and Coincidence Problem Symmetry doi: 10.3390/sym10090411 Authors: Alexander B. Balakin Alexei S. Ilin We study a new exactly solvable model of coupling of the Dark Energy and Dark Matter, in the framework of which the kernel of non-gravitational interaction is presented by the integral Volterra-type operator well-known in the classical theory of fading memory. Exact solutions of this isotropic homogeneous cosmological model were classified with respect to the sign of the discriminant of the cubic characteristic polynomial associated with the key equation of the model. Energy-density scalars of the Dark Energy and Dark Matter, the Hubble function and acceleration parameter are presented explicitly; the scale factor is found in quadratures. Asymptotic analysis of the exact solutions has shown that the Big Rip, Little Rip, Pseudo Rip regimes can be realized with the specific choice of guiding parameters of the model. We show that the Coincidence problem can be solved if we consider the memory effect associated with the interactions in the Dark Sector of the universe.
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  • 61
    Publication Date: 2018-09-19
    Description: Symmetry, Vol. 10, Pages 409: Determining An Unknown Boundary Condition by An Iteration Method Symmetry doi: 10.3390/sym10090409 Authors: Dejian Huang Yanqing Li Donghe Pei This paper investigates the boundary value in the heat conduction problem by a variational iteration method. Applying the iteration method, a sequence of convergent functions is constructed, the limit approximates the exact solution of the heat conduction equation in a few iterations using only the initial condition. This method does not require discretization of the variables. Numerical results show that this method is quite simple and straightforward for models that are currently under research.
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  • 62
    Publication Date: 2018-09-22
    Description: Symmetry, Vol. 10, Pages 427: On the Classification of Bol-Moufang Type of Some Varieties of Quasi Neutrosophic Triplet Loop (Fenyves BCI-Algebras) Symmetry doi: 10.3390/sym10100427 Authors: Tèmítọ́pẹ́ Gbọ́láhàn Jaíyéọlá Emmanuel Ilojide Memudu Olaposi Olatinwo Florentin Smarandache In this paper, Bol-Moufang types of a particular quasi neutrosophic triplet loop (BCI-algebra), chritened Fenyves BCI-algebras are introduced and studied. 60 Fenyves BCI-algebras are introduced and classified. Amongst these 60 classes of algebras, 46 are found to be associative and 14 are found to be non-associative. The 46 associative algebras are shown to be Boolean groups. Moreover, necessary and sufficient conditions for 13 non-associative algebras to be associative are also obtained: p-semisimplicity is found to be necessary and sufficient for a F 3 , F 5 , F 42 and F 55 algebras to be associative while quasi-associativity is found to be necessary and sufficient for F 19 , F 52 , F 56 and F 59 algebras to be associative. Two pairs of the 14 non-associative algebras are found to be equivalent to associativity ( F 52 and F 55 , and F 55 and F 59 ). Every BCI-algebra is naturally an F 54 BCI-algebra. The work is concluded with recommendations based on comparison between the behaviour of identities of Bol-Moufang (Fenyves’ identities) in quasigroups and loops and their behaviour in BCI-algebra. It is concluded that results of this work are an initiation into the study of the classification of finite Fenyves’ quasi neutrosophic triplet loops (FQNTLs) just like various types of finite loops have been classified. This research work has opened a new area of research finding in BCI-algebras, vis-a-vis the emergence of 540 varieties of Bol-Moufang type quasi neutrosophic triplet loops. A ‘Cycle of Algebraic Structures’ which portrays this fact is provided.
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  • 63
    Publication Date: 2018-09-22
    Description: Symmetry, Vol. 10, Pages 426: General (α,2)-Path Sum-Connectivirty Indices of One Important Class of Polycyclic Aromatic Hydrocarbons Symmetry doi: 10.3390/sym10100426 Authors: Haiying Wang The general ( α , t ) -path sum-connectivity index of a molecular graph originates from many practical problems, such as the three-dimensional quantitative structure–activity relationships (3D QSAR) and molecular chirality. For arbitrary nonzero real number α and arbitrary positive integer t, it is defined as t χ α ( G ) = ∑ P t = v i 1 v i 2 ⋯ v i t + 1 ⊆ G [ d G ( v i 1 ) d G ( v i 2 ) ⋯ d G ( v i t + 1 ) ] α , where we take the sum over all possible paths of length t of G and two paths v i 1 v i 2 ⋯ v i t + 1 and v i t + 1 ⋯ v i 2 v i 1 are considered to be one path. In this work, one important class of polycyclic aromatic hydrocarbons and their structures are firstly considered, which play a role in organic materials and medical sciences. We try to compute the exact general ( α , 2 ) -path sum-connectivity indices of these hydrocarbon systems. Furthermore, we exactly derive the monotonicity and the extremal values of these polycyclic aromatic hydrocarbons for any real number α . These valuable results could produce strong guiding significance to these applied sciences.
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  • 64
    Publication Date: 2018-09-22
    Description: Symmetry, Vol. 10, Pages 425: Astrape: An Efficient Concurrent Cloud Attestation with Ciphertext-Policy Attribute-Based Encryption Symmetry doi: 10.3390/sym10100425 Authors: Haihe Ba Huaizhe Zhou Songzhu Mei Huidong Qiao Tie Hong Zhiying Wang Jiangchun Ren Cloud computing emerges as a change in the business paradigm that offers pay-as-you-go computing capability and brings enormous benefits, but there are numerous organizations showing hesitation for the adoption of cloud computing due to security concerns. Remote attestation has been proven to boost confidence in clouds to guarantee hosted cloud applications’ integrity. However, the state-of-the-art attestation schemes do not fit that multiple requesters raise their challenges simultaneously, thereby leading to larger performance overheads on the attester side. To address that, we propose an efficient and trustworthy concurrent attestation architecture under multi-requester scenarios, Astrape, to improve efficiency in the integrity and confidentiality protection aspects to generate an unforgeable and encrypted attestation report. Specifically, we propose two key techniques in this paper. The first one—aggregated attestation signature—reliably protects the attestation content from being compromised even in the presence of adversaries who have full control of the network, therefore successfully providing attestation integrity. The second one—delegation-based controlled report—introduces a third-party service to distribute the attestation report to requesters in order to save computation and communication overload on the attested party. The report is encrypted with an access policy by using attribute-based encryption and accessed by a limited number of qualified requesters, hence supporting attestation confidentiality. The experimental results show that Astrape can take no more than 0.4 s to generate an unforgeable and encrypted report for 1000 requesters and deliver a throughput speedup of approximately 30 × in comparison to the existing attestation systems.
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  • 65
    Publication Date: 2018-09-22
    Description: Symmetry, Vol. 10, Pages 424: (Gravitational) Vacuum Cherenkov Radiation Symmetry doi: 10.3390/sym10100424 Authors: Marco Schreck This work reviews our current understanding of Cherenkov-type processes in vacuum that may occur due to a possible violation of Lorentz invariance. The description of Lorentz violation is based on the Standard Model Extension (SME). To get an overview as general as possible, the most important findings for vacuum Cherenkov radiation in Minkowski spacetime are discussed. After doing so, special emphasis is put on gravitational Cherenkov radiation. For a better understanding, the essential properties of the gravitational SME are recalled in this context. The common grounds and differences of vacuum Cherenkov radiation in Minkowski spacetime and in the gravity sector are emphasized.
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  • 66
    Publication Date: 2018-08-09
    Description: Symmetry, Vol. 10, Pages 329: Barycenter Theorem in Phase Characteristics of Symmetric and Asymmetric Windows Symmetry doi: 10.3390/sym10080329 Authors: Jiufei Luo Haitao Xu Kai Zheng Xinyi Li Song Feng Asymmetric windows are of increasing interest to researchers because of the nonlinear and adjustable phase response, as well as alterable time delay. Short-time phase distortion can provide an essential improvement in speech coding, and also has better performance in speech recognition. The merits of asymmetric windows in the aspect of spectral behaviors have an important function in frequency component detection and parameter estimation. In this paper, the phase response of windows were further studied, and the phase characteristics of symmetric and asymmetric windows are described. The relationship between the barycenter of windows in the time domain, and the phase characteristic at the center of the main lobe in the frequency domain, was established. In light of the relationship, an improved version of the asymmetric window- based frequency estimation algorithm was proposed. The improved algorithm has advantages of straightforward implementation and computational efficiency. The numeric simulation results also indicate that the improved approach is more robust than the traditional method against additive random noise.
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  • 67
    Publication Date: 2018-08-10
    Description: Symmetry, Vol. 10, Pages 330: Multiple-Attribute Decision-Making Method Using Similarity Measures of Hesitant Linguistic Neutrosophic Numbers Regarding Least Common Multiple Cardinality Symmetry doi: 10.3390/sym10080330 Authors: Wenhua Cui Jun Ye Linguistic neutrosophic numbers (LNNs) are a powerful tool for describing fuzzy information with three independent linguistic variables (LVs), which express the degrees of truth, uncertainty, and falsity, respectively. However, existing LNNs cannot depict the hesitancy of the decision-maker (DM). To solve this issue, this paper first defines a hesitant linguistic neutrosophic number (HLNN), which consists of a few LNNs regarding an evaluated object due to DMs’ hesitancy to represent their hesitant and uncertain information in the decision-making process. Then, based on the least common multiple cardinality (LCMC), we present generalized distance and similarity measures of HLNNs, and then develop a similarity measure-based multiple-attribute decision-making (MADM) method to handle the MADM problem in the HLNN setting. Finally, the feasibility of the proposed approach is verified by an investment decision case.
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  • 68
    Publication Date: 2018-08-11
    Description: Symmetry, Vol. 10, Pages 334: Novel Procedure for Designing and 3D Printing a Customized Surgical Template for Arthrodesis Surgery on the Sacrum Symmetry doi: 10.3390/sym10080334 Authors: Francesco Naddeo Alessandro Naddeo Nicola Cappetti Emilio Cataldo Riccardo Militio In this article, the authors propose a novel procedure for designing a customized 3D-printed surgical template to guide surgeons in inserting screws into the sacral zone during arthrodesis surgeries. The template is characterized by two cylindrical guides defined by means of trajectories identified, based on standard procedure, via an appropriate Computer-Aided-Design (CAD)-based procedure. The procedure is based on the definition of the insertion direction by means of anatomical landmarks that enable the screws to take advantage of the maximum available bone path. After 3D printing, the template adheres perfectly to the bone surface, showing univocal positioning by exploiting the foramina of the sacrum, great maneuverability due to the presence of an ergonomic handle, as well as a break system for the two independent guides. These features make the product innovative. Thanks to its small size and the easy anchoring, the surgeon can simply position the template on the insertion area and directly insert the screws, without alterations to standard surgical procedures. This has the effect of reducing the overall duration of the surgery and the patient’s exposure to X-rays, and increasing both the safety of the intervention and the quality of the results.
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  • 69
    Publication Date: 2018-08-17
    Description: Symmetry, Vol. 10, Pages 344: Perception of 3D Symmetrical and Nearly Symmetrical Shapes Symmetry doi: 10.3390/sym10080344 Authors: Vijai Jayadevan Tadamasa Sawada Edward Delp Zygmunt Pizlo The human visual system uses priors to convert an ill-posed inverse problem of 3D shape recovery into a well-posed one. In previous studies, we have demonstrated the use of priors like symmetry, compactness and minimal surface in the perception of 3D symmetric shapes. We also showed that binocular perception of symmetric shapes can be well modeled by the above-mentioned priors and binocular depth order information. In this study, which used a shape-matching task, we show that these priors can also be used to model perception of near-symmetrical shapes. Our near-symmetrical shapes are asymmetrical shapes obtained from affine distortions of symmetrical shapes. We found that the perception of symmetrical shapes is closer to veridical than the perception of asymmetrical shapes is. We introduce a metric to measure asymmetry of abstract polyhedral shapes, and a similar metric to measure shape dissimilarity between two polyhedral shapes. We report some key observations obtained by analyzing the data from the experiment. A website was developed with all the shapes used in the experiment, along with the shapes recovered by the subject and the shapes recovered by the model. This website provides a qualitative analysis of the effectiveness of the model and also helps demonstrate the goodness of the shape metric.
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  • 70
    Publication Date: 2018-08-17
    Description: Symmetry, Vol. 10, Pages 343: Three-Body Dispersion Potentials Involving Electric Octupole Coupling Symmetry doi: 10.3390/sym10080343 Authors: Stefan Buhmann A. Salam Non-pairwise additive three-body dispersion potentials dependent upon one or more electric octupole moments are evaluated using the theory of molecular quantum electrodynamics. To simplify the perturbation theory calculations, an effective two-photon interaction Hamiltonian operator is employed. This leads to only third-order theory being required to evaluate energy shifts instead of the usual sixth-order formula, and the summation over six time-ordered sequences of virtual photon creation and annihilation events. Specific energy shifts computed include DD-DD-DO, DD-DO-DO, DO-DO-DO, and DD-DO-OO terms, where D and O are electric dipole and octupole moments, respectively. The formulae obtained are applicable to an arbitrary arrangement of the three particles, and we present explicit results for the equilateral triangle and collinear configurations, which complements the recently published DD-DD-OO potential. In this last case it was found that the contribution from the octupole weight-1 term could be viewed as a higher-order correction to the triple-dipole dispersion potential DD-DD-DD. In a similar fashion the octupole moment is decomposed into its irreducible components of weights-1 and -3, enabling insight to be gained into the potentials obtained in this study. Dispersion interaction energies proportional to mixed dipole-octupole polarisabilities, for example, are found to depend only on the weight-1 octupole moment for isotropic species and are retarded. Additional approximations are necessary in the evaluation of wave vector integrals for these cases in order to yield energy shifts that are valid in the near-zone.
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  • 71
    Publication Date: 2018-08-19
    Description: Symmetry, Vol. 10, Pages 347: Skin Lesion Segmentation Method for Dermoscopy Images Using Artificial Bee Colony Algorithm Symmetry doi: 10.3390/sym10080347 Authors: Mohanad Aljanabi Yasa Ekşioğlu Özok Javad Rahebi Ahmad S. Abdullah The occurrence rates of melanoma are rising rapidly, which are resulting in higher death rates. However, if the melanoma is diagnosed in Phase I, the survival rates increase. The segmentation of the melanoma is one of the largest tasks to undertake and achieve when considering both beneath and over the segmentation. In this work, a new approach based on the artificial bee colony (ABC) algorithm is proposed for the detection of melanoma from digital images. This method is simple, fast, flexible, and requires fewer parameters compared with other algorithms. The proposed approach is applied on the PH2, ISBI 2016 challenge, the ISBI 2017 challenge, and Dermis datasets. These bases contained images are affected by different abnormalities. The formation of the databases consists of images collected from different sources; they are bases with different types of resolution, lighting, etc., so in the first step, the noise was removed from the images by using morphological filtering. In the next step, the ABC algorithm is used to find the optimum threshold value for the melanoma detection. The proposed approach achieved good results in the conditions of high specificity. The experimental results suggest that the proposed method accomplished higher performance compared to the ground truth images supported by a Dermatologist. For the melanoma detection, the method achieved an average accuracy and Jaccard’s coefficient in the range of 95.24–97.61%, and 83.56–85.25% in these four databases. To show the robustness of this work, the results were compared to existing methods in the literature for melanoma detection. High values for estimation performance confirmed that the proposed melanoma detection is better than other algorithms, which demonstrates the highly differential power of the newly introduced features.
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  • 72
    Publication Date: 2018-08-18
    Description: Symmetry, Vol. 10, Pages 346: A Neutrosophic Set Based Fault Diagnosis Method Based on Multi-Stage Fault Template Data Symmetry doi: 10.3390/sym10080346 Authors: Wen Jiang Yu Zhong Xinyang Deng Fault diagnosis is an important issue in various fields and aims to detect and identify the faults of systems, products, and processes. The cause of a fault is complicated due to the uncertainty of the actual environment. Nevertheless, it is difficult to consider uncertain factors adequately with many traditional methods. In addition, the same fault may show multiple features and the same feature might be caused by different faults. In this paper, a neutrosophic set based fault diagnosis method based on multi-stage fault template data is proposed to solve this problem. For an unknown fault sample whose fault type is unknown and needs to be diagnosed, the neutrosophic set based on multi-stage fault template data is generated, and then the generated neutrosophic set is fused via the simplified neutrosophic weighted averaging (SNWA) operator. Afterwards, the fault diagnosis results can be determined by the application of defuzzification method for a defuzzying neutrosophic set. Most kinds of uncertain problems in the process of fault diagnosis, including uncertain information and inconsistent information, could be handled well with the integration of multi-stage fault template data and the neutrosophic set. Finally, the practicality and effectiveness of the proposed method are demonstrated via an illustrative example.
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  • 73
    Publication Date: 2018-08-21
    Description: Symmetry, Vol. 10, Pages 352: PUF Based Authentication Protocol for IoT Symmetry doi: 10.3390/sym10080352 Authors: An Braeken Key agreement between two constrained Internet of Things (IoT) devices that have not met each other is an essential feature to provide in order to establish trust among its users. Physical Unclonable Functions (PUFs) on a device represent a low cost primitive exploiting the unique random patterns in the device and have been already applied in a multitude of applications for secure key generation and key agreement in order to avoid an attacker to take over the identity of a tampered device, whose key material has been extracted. This paper shows that the key agreement scheme of a recently proposed PUF based protocol, presented by Chatterjee et al., for Internet of Things (IoT) is vulnerable for man-in-the-middle, impersonation, and replay attacks in the Yao–Dolev security model. We propose an alternative scheme, which is able to solve these issues and can provide in addition a more efficient key agreement and subsequently a communication phase between two IoT devices connected to the same authentication server. The scheme also offers identity based authentication and repudiation, when only using elliptic curve multiplications and additions, instead of the compute intensive pairing operations.
    Electronic ISSN: 2073-8994
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  • 74
    Publication Date: 2018-08-21
    Description: Symmetry, Vol. 10, Pages 350: Commutative Generalized Neutrosophic Ideals in BCK-Algebras Symmetry doi: 10.3390/sym10080350 Authors: Rajab Ali Borzooei Xiaohong Zhang Florentin Smarandache Young Bae Jun The concept of a commutative generalized neutrosophic ideal in a B C K -algebra is proposed, and related properties are proved. Characterizations of a commutative generalized neutrosophic ideal are considered. Also, some equivalence relations on the family of all commutative generalized neutrosophic ideals in B C K -algebras are introduced, and some properties are investigated.
    Electronic ISSN: 2073-8994
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  • 75
    Publication Date: 2018-08-21
    Description: Symmetry, Vol. 10, Pages 351: Agustín de Betancourt’s Double-Acting Steam Engine: Geometric Modeling and Virtual Reconstruction Symmetry doi: 10.3390/sym10080351 Authors: José Ignacio Rojas-Sola Belén Galán-Moral Eduardo De la Morena-De la Fuente In this paper, the geometric modeling and virtual reconstruction of the double-acting steam engine designed by Agustín de Betancourt in 1789 are shown. For this, the software Autodesk Inventor Professional is used, which has allowed us to obtain its geometric documentation. The material for the research is available on the website of the Betancourt Project of the Canary Orotava Foundation for the History of Science. Almost all parts of the steam engine are drawn on the sheets, but due to the absence of scale and space, it is insufficient to obtain an accurate and reliable 3D CAD (Computer-Aided Design) model. For this reason a graphic scale has been adopted so that the dimensions of the elements are coherent. Also, it has been necessary to make some dimensional and geometric hypotheses, as well as restrictions of movement (degrees of freedom). Geometric modeling has made it possible to know that the system is balanced with the geometric center of the rocker arm shaft, and presents an energetic symmetry whose axis is the support of the parallelogram where the shaft rests: calorific energy to the left and mechanical energy to the right, with the rocker arm acting as a transforming element from one to the other.
    Electronic ISSN: 2073-8994
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  • 76
    Publication Date: 2018-08-22
    Description: Symmetry, Vol. 10, Pages 356: Symmetry in Regular Polyhedra Seen as 2D Möbius Transformations: Geodesic and Panel Domes Arising from 2D Diagrams Symmetry doi: 10.3390/sym10090356 Authors: Jose A. Diaz-Severiano Valentin Gomez-Jauregui Cristina Manchado Cesar Otero This paper shows a methodology for reducing the complex design process of space structures to an adequate selection of points lying on a plane. This procedure can be directly implemented in a bi-dimensional plane when we substitute (i) Euclidean geometry by bi-dimensional projection of the elliptic geometry and (ii) rotations/symmetries on the sphere by Möbius transformations on the plane. These graphs can be obtained by sites, specific points obtained by homological transformations in the inversive plane, following the analogous procedure defined previously in the three-dimensional space. From the sites, it is possible to obtain different partitions of the plane, namely, power diagrams, Voronoi diagrams, or Delaunay triangulations. The first would generate geo-tangent structures on the sphere; the second, panel structures; and the third, lattice structures.
    Electronic ISSN: 2073-8994
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  • 77
    Publication Date: 2018-08-22
    Description: Symmetry, Vol. 10, Pages 355: Orchard Free Space and Center Line Estimation Using Naive Bayesian Classifier for Unmanned Ground Self-Driving Vehicle Symmetry doi: 10.3390/sym10090355 Authors: Hong-Kun Lyu Chi-Ho Park Dong-Hee Han Seong Woo Kwak Byeongdae Choi In the case of autonomous orchard navigation, researchers have developed algorithms that utilize features, such as trunks, canopies, and sky in orchards, but there are still various difficulties in recognizing free space for autonomous navigation in a changing agricultural environment. In this study, we applied the Naive Bayesian classification to detect the boundary between the trunk and the ground and propose an algorithm to determine the center line of free space. The naïve Bayesian classification requires a small number of samples for training and a simple training process. In addition, it was able to effectively classify tree trunk’s points and noise points of the orchard, which are problematic in vision-based processing, and noise caused by small branches, soil, weeds, and tree shadows on the ground. The performance of the proposed algorithm was investigated using 229 sample images obtained from an image acquisition system with a Complementary Metal Oxide Semiconductor (CMOS) Image Sensor (CIS) camera. The center line detected by the unaided-eye manual decision and the results extracted by the proposed algorithm were compared and analyzed for several parameters. In all compared parameters, extracted center line was more stable than the manual center line results.
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  • 78
    Publication Date: 2018-08-24
    Description: Symmetry, Vol. 10, Pages 358: Positive Solutions for a Three-Point Boundary Value Problem of Fractional Q-Difference Equations Symmetry doi: 10.3390/sym10090358 Authors: Chen Yang In this work, a three-point boundary value problem of fractional q-difference equations is discussed. By using fixed point theorems on mixed monotone operators, some sufficient conditions that guarantee the existence and uniqueness of positive solutions are given. In addition, an iterative scheme can be made to approximate the unique solution. Finally, some interesting examples are provided to illustrate the main results.
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  • 79
    Publication Date: 2018-08-25
    Description: Symmetry, Vol. 10, Pages 360: Hyperbolicity on Graph Operators Symmetry doi: 10.3390/sym10090360 Authors: J. A. Méndez-Bermúdez Rosalío Reyes José M. Rodríguez José M. Sigarreta A graph operator is a mapping F : Γ → Γ ′ , where Γ and Γ ′ are families of graphs. The different kinds of graph operators are an important topic in Discrete Mathematics and its applications. The symmetry of this operations allows us to prove inequalities relating the hyperbolicity constants of a graph G and its graph operators: line graph, Λ ( G ) ; subdivision graph, S ( G ) ; total graph, T ( G ) ; and the operators R ( G ) and Q ( G ) . In particular, we get relationships such as δ ( G ) ≤ δ ( R ( G ) ) ≤ δ ( G ) + 1 / 2 , δ ( Λ ( G ) ) ≤ δ ( Q ( G ) ) ≤ δ ( Λ ( G ) ) + 1 / 2 , δ ( S ( G ) ) ≤ 2 δ ( R ( G ) ) ≤ δ ( S ( G ) ) + 1 and δ ( R ( G ) ) − 1 / 2 ≤ δ ( Λ ( G ) ) ≤ 5 δ ( R ( G ) ) + 5 / 2 for every graph which is not a tree. Moreover, we also derive some inequalities for the Gromov product and the Gromov product restricted to vertices.
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  • 80
    Publication Date: 2018-08-27
    Description: Symmetry, Vol. 10, Pages 364: A linguistic Neutrosophic Multi-Criteria Group Decision-Making Method to University Human Resource Management Symmetry doi: 10.3390/sym10090364 Authors: Ru-xia Liang Zi-bin Jiang Jian-qiang Wang Competition among different universities depends largely on the competition for talent. Talent evaluation and selection is one of the main activities in human resource management (HRM) which is critical for university development. Firstly, linguistic neutrosophic sets (LNSs) are introduced to better express multiple uncertain information during the evaluation procedure. We further merge the power averaging operator with LNSs for information aggregation and propose a LN-power weighted averaging (LNPWA) operator and a LN-power weighted geometric (LNPWG) operator. Then, an extended technique for order preference by similarity to ideal solution (TOPSIS) method is developed to solve a case of university HRM evaluation problem. The main contribution and novelty of the proposed method rely on that it allows the information provided by different decision makers (DMs) to support and reinforce each other which is more consistent with the actual situation of university HRM evaluation. In addition, its effectiveness and advantages over existing methods are verified through sensitivity and comparative analysis. The results show that the proposal is capable in the domain of university HRM evaluation and may contribute to the talent introduction in universities.
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  • 81
    Publication Date: 2018-08-27
    Description: Symmetry, Vol. 10, Pages 362: Investigation on the Effect of Type of Cooling on the Properties of Aluminum Alloy during Warm/Hot Hydromechanical Deep Drawing Symmetry doi: 10.3390/sym10090362 Authors: Gaoshen Cai Chuanyu Wu Dongxing Zhang The warm sheet cylindrical deep drawing experiment of aluminum alloy was carried out and macro-mechanical properties and microstructure evolution of hydro-formed cups with different cooling medium were analyzed, which aimed to investigate the effects of different types of cooling on mechanical properties and microstructure of cylindrical cups hydro-formed by warm Hydro-mechanical Deep Drawing (HDD). Results show that, under the condition of warm hydroforming, the mechanical properties such as yield stress and ultimate strength were influenced very little by air or water cooling. Grain coarsening of these hydro-formed cups can be inhibited to a certain extent with subsequent rapid water cooling. Moreover, it shows that the processing with warm sheet hydroforming and subsequent rapid cooling of 7075-O aluminum alloy has a positive significance in maintaining the stability of macro mechanical properties and inhibiting the degradation of the microstructure of materials.
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  • 82
    Publication Date: 2018-08-27
    Description: Symmetry, Vol. 10, Pages 363: Positive Solutions of One-Dimensional p-Laplacian Problems with Superlinearity Symmetry doi: 10.3390/sym10090363 Authors: G.C. Yang Z.Y. Li We study one-dimensional p-Laplacian problems and answer the unsolved problem. Our method is to study the property of the operator, the concavity of the solutions and the continuity of the first eigenvalues. By the above study, the main difficulty is overcome and the fixed point theorem can be applied for the corresponding compact maps. An affirmative answer is given to the unsolved problem with superlinearity. A global growth condition is not imposed on the nonlinear term f. The assumptions of this paper are more general than the usual, thus the existing results cannot be utilized. Some recent results are improved from weak solutions to classical solutions and from p ≥ 2 to p ∈ ( 1 , ∞ ) .
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  • 83
    Publication Date: 2018-08-30
    Description: Symmetry, Vol. 10, Pages 367: The New Similarity Measure and Distance Measure of a Hesitant Fuzzy Linguistic Term Set Based on a Linguistic Scale Function Symmetry doi: 10.3390/sym10090367 Authors: Donghai Liu Yuanyuan Liu Xiaohong Chen The existing cosine similarity measure for hesitant fuzzy linguistic term sets (HFLTSs) has an impediment as it does not satisfy the axiom of similarity measure. Due to this disadvantage, a new similarity measure combining the existing cosine similarity measure and the Euclidean distance measure of HFLTSs is proposed, which is constructed based on a linguistic scale function; the related properties are also given. According to the relationship between the distance measure and the similarity measure, a corresponding distance measure between HFLTSs is obtained. Furthermore, we generalize the technique for order preference by similarity to an ideal solution (TOPSIS) method to the obtained distance measure of the HFLTSs. The principal advantages of the proposed method are that it cannot only effectively transform linguistic information in different semantic environments, but it can also avoid the shortcomings of existing the cosine similarity measure. Finally, a case study is conducted to illustrate the feasibility and effectiveness of the proposed method, which is compared to the existing methods.
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  • 84
    Publication Date: 2018-09-01
    Description: Symmetry, Vol. 10, Pages 368: On Non-Linear Behavior of Viscosity in Low-Concentration Solutions and Aggregate Structures Symmetry doi: 10.3390/sym10090368 Authors: Vasilis K. Oikonomou In this paper, an experimental method that may reveal possible aggregate symmetrical structures in highly diluted solutions is proposed, generated by the method of the release activity, which is not yet completely proven. The release activity phenomenon (regardless of whether or not it is real) could be viewed as being quite controversial. However, the focus of this paper is to reveal any possible higher-order, pragmatic, underlying symmetry or structure supporting this theory, by proposing an experiment based on viscosity. Our proposal is based on the sequential measurement of the viscosity of a highly diluted solution and the perturbative expansion of the viscosity as a function of the concentration. The coefficients of this perturbative expansion directly quantify the modification of the hydrodynamic flow around particles and around higher-order structures. Any deviation from a linear dependence of the viscosity, as a function of the concentration, could potentially reveal a collective structure of some sort, or some symmetrical pattern in the solvent. We describe our experimental proposal for non-electrolyte solutes, and future directions for revealing collective structures in solutions are discussed as related to the release activity method. Regardless of whether or not the release activity is pragmatic, it needs to be scrutinized in order to reveal its inner workings. Finally, some theoretical arguments are presented to support the proposal.
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  • 85
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 373: New Concepts on Vertex and Edge Coloring of Simple Vague Graphs Symmetry doi: 10.3390/sym10090373 Authors: Arindam Dey Le Hoang Son P. K. Kishore Kumar Ganeshsree Selvachandran Shio Gai Quek The vague graph has found its importance as a closer approximation to real life situations. A review of the literature in this area reveals that the edge coloring problem for vague graphs has not been studied until now. Therefore, in this paper, we analyse the concept of vertex and edge coloring on simple vague graphs. Specifically, two new definitions for vague graphs related to the concept of the λ-strong-adjacent and ζ-strong-incident of vague graphs are introduced. We consider the color classes to analyze the coloring on the vertices in vague graphs. The proposed method illustrates the concept of coloring on vague graphs, using the definition of color class, which depends only on the truth membership function. Applications of the proposal in solving practical problems related to traffic flow management and the selection of advertisement spots are mainly discussed.
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  • 86
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 374: Introduction to the Special Issue: Applications of Internet of Things Symmetry doi: 10.3390/sym10090374 Authors: Chi-Hua Chen Eyhab Al-Masri Feng-Jang Hwang Despo Ktoridou Kuen-Rong Lo This editorial introduces the special issue, entitled “Applications of Internet of Things”, of Symmetry. The topics covered in this issue fall under four main parts: (I) communication techniques and applications, (II) data science techniques and applications, (III) smart transportation, and (IV) smart homes. Four papers on sensing techniques and applications are included as follows: (1) “Reliability of improved cooperative communication over wireless sensor networks”, by Chen et al.; (2) “User classification in crowdsourcing-based cooperative spectrum sensing”, by Zhai and Wang; (3) “IoT’s tiny steps towards 5G: Telco’s perspective”, by Cero et al.; and (4) “An Internet of things area coverage analyzer (ITHACA) for complex topographical scenarios”, by Parada et al. One paper on data science techniques and applications is as follows: “Internet of things: a scientometric review”, by Ruiz-Rosero et al. Two papers on smart transportation are as follows: (1) “An Internet of things approach for extracting featured data using an AIS database: an application based on the viewpoint of connected ships”, by He et al.; and (2) “The development of key technologies in applications of vessels connected to the Internet”, by Tian et al. Two papers on smart home are as follows: (1) “A novel approach based on time cluster for activity recognition of daily living in smart homes”, by Liu et al.; and (2) “IoT-based image recognition system for smart home-delivered meal services”, by Tseng et al.
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  • 87
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 375: Unsupervised Multi-Object Detection for Video Surveillance Using Memory-Based Recurrent Attention Networks Symmetry doi: 10.3390/sym10090375 Authors: Zhen He Hangen He Nowadays, video surveillance has become ubiquitous with the quick development of artificial intelligence. Multi-object detection (MOD) is a key step in video surveillance and has been widely studied for a long time. The majority of existing MOD algorithms follow the “divide and conquer” pipeline and utilize popular machine learning techniques to optimize algorithm parameters. However, this pipeline is usually suboptimal since it decomposes the MOD task into several sub-tasks and does not optimize them jointly. In addition, the frequently used supervised learning methods rely on the labeled data which are scarce and expensive to obtain. Thus, we propose an end-to-end Unsupervised Multi-Object Detection framework for video surveillance, where a neural model learns to detect objects from each video frame by minimizing the image reconstruction error. Moreover, we propose a Memory-Based Recurrent Attention Network to ease detection and training. The proposed model was evaluated on both synthetic and real datasets, exhibiting its potential.
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  • 88
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 371: Intertemporal Choice of Fuzzy Soft Sets Symmetry doi: 10.3390/sym10090371 Authors: José Carlos R. Alcantud María José Muñoz Torrecillas This paper first merges two noteworthy aspects of choice. On the one hand, soft sets and fuzzy soft sets are popular models that have been largely applied to decision making problems, such as real estate valuation, medical diagnosis (glaucoma, prostate cancer, etc.), data mining, or international trade. They provide crisp or fuzzy parameterized descriptions of the universe of alternatives. On the other hand, in many decisions, costs and benefits occur at different points in time. This brings about intertemporal choices, which may involve an indefinitely large number of periods. However, the literature does not provide a model, let alone a solution, to the intertemporal problem when the alternatives are described by (fuzzy) parameterizations. In this paper, we propose a novel soft set inspired model that applies to the intertemporal framework, hence it fills an important gap in the development of fuzzy soft set theory. An algorithm allows the selection of the optimal option in intertemporal choice problems with an infinite time horizon. We illustrate its application with a numerical example involving alternative portfolios of projects that a public administration may undertake. This allows us to establish a pioneering intertemporal model of choice in the framework of extended fuzzy set theories.
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  • 89
    Publication Date: 2018-09-02
    Description: Symmetry, Vol. 10, Pages 376: 3D Spatial Pyramid Dilated Network for Pulmonary Nodule Classification Symmetry doi: 10.3390/sym10090376 Authors: Guokai Zhang Xiao Liu Dandan Zhu Pengcheng He Lipeng Liang Ye Luo Jianwei Lu Lung cancer mortality is currently the highest among all kinds of fatal cancers. With the help of computer-aided detection systems, a timely detection of malignant pulmonary nodule at early stage could improve the patient survival rate efficiently. However, the sizes of the pulmonary nodules are usually various, and it is more difficult to detect small diameter nodules. The traditional convolution neural network uses pooling layers to reduce the resolution progressively, but it hampers the network’s ability to capture the tiny but vital features of the pulmonary nodules. To tackle this problem, we propose a novel 3D spatial pyramid dilated convolution network to classify the malignancy of the pulmonary nodules. Instead of using the pooling layers, we use 3D dilated convolution to learn the detailed characteristic information of the pulmonary nodules. Furthermore, we show that the fusion of multiple receptive fields from different dilated convolutions could further improve the classification performance of the model. Extensive experimental results demonstrate that our model achieves a better result with an accuracy of 88 . 6 % , which outperforms other state-of-the- art methods.
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  • 90
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 378: Applications of Differential Form Wu’s Method to Determine Symmetries of (Partial) Differential Equations Symmetry doi: 10.3390/sym10090378 Authors: Temuer Chaolu Sudao Bilige In this paper, we present an application of Wu’s method (differential characteristic set (dchar-set) algorithm) for computing the symmetry of (partial) differential equations (PDEs) that provides a direct and systematic procedure to obtain the classical and nonclassical symmetry of the differential equations. The fundamental theory and subalgorithms used in the proposed algorithm consist of a different version of the Lie criterion for the classical symmetry of PDEs and the zero decomposition algorithm of a differential polynomial (d-pol) system (DPS). The version of the Lie criterion yields determining equations (DTEs) of symmetries of differential equations, even those including a nonsolvable equation. The decomposition algorithm is used to solve the DTEs by decomposing the zero set of the DPS associated with the DTEs into a union of a series of zero sets of dchar-sets of the system, which leads to simplification of the computations.
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  • 91
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 377: The Absolute Ruin Insurance Risk Model with a Threshold Dividend Strategy Symmetry doi: 10.3390/sym10090377 Authors: Wenguang Yu Yujuan Huang Chaoran Cui The absolute ruin insurance risk model is modified by including some valuable market economic information factors, such as credit interest, debit interest and dividend payments. Such information is especially important for insurance companies to control risks. We further assume that the insurance company is able to finance and continue to operate when its reserve is negative. We investigate the integro-differential equations for some interest actuarial diagnostics. We also provide numerical examples to explain the effects of relevant parameters on actuarial diagnostics.
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  • 92
    Publication Date: 2018-09-04
    Description: Symmetry, Vol. 10, Pages 379: Effective Blind Frequency Offset Estimation Scheme for BST-OFDM Based HDTV Broadcast Systems Symmetry doi: 10.3390/sym10090379 Authors: Yong-An Jung Young-Hwan You The integrated services digital broadcasting-terrestrial (ISDB-T) system is designed in order to accommodate high-quality video/audio and multimedia services, using band segmented transmission orthogonal frequency division multiplexing (BST-OFDM) scheme. In the ISDB-T system, the pilot configuration varies depending on whether a segment uses a coherent or differential modulation. Therefore, it is necessary to perform a joint estimation of carrier frequency offset (CFO) and sampling frequency offset (SFO) independent of the segment format in the ISDB-T system. The goal is to complete those synchronization tasks while considering an information-carrying transmission and multiplexing configuration control (TMCC) signal as pilot symbols. It is demonstrated through numerical simulations that the differential BPSK-modulated TMCC information can be efficiently used for a least-squares estimation of CFO and SFO, offering an acceptable performance.
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  • 93
    Publication Date: 2018-09-07
    Description: Symmetry, Vol. 10, Pages 385: Accurate Age Estimation Using Multi-Task Siamese Network-Based Deep Metric Learning for Front Face Images Symmetry doi: 10.3390/sym10090385 Authors: Yoosoo Jeong Seungmin Lee Daejin Park Kil Houm Park Recently, there have been many studies on the automatic extraction of facial information using machine learning. Age estimation from front face images is becoming important, with various applications. Our proposed work is based on the binary classifier, which only determines whether two input images are clustered in a similar class, and trains the convolutional neural networks (CNNs) model using the deep metric learning method based on the Siamese network. To converge the results of the training Siamese network, two classes, for which age differences are below a certain level of distance, are considered as the same class, so the ratio of positive database images is increased. The deep metric learning method trains the CNN model to measure similarity based on only age data, but we found that the accumulated gender data can also be used to compare ages. From this experimental fact, we adopted a multi-task learning approach to consider the gender data for more accurate age estimation. In the experiment, we evaluated our approach using MORPH and MegaAge-Asian datasets, and compared gender classification accuracy only using age data from the training images. In addition, from the gender classification, we found that our proposed architecture, which is trained with only age data, performs age comparison by using the self-generated gender feature. The accuracy enhancement by multi-task learning, for the simultaneous consideration of age and gender data, is discussed. Our approach results in the best accuracy among the methods based on deep metric learning on MORPH dataset. Additionally, our method is also the best results compared with the results of the state of art in terms of age estimation on MegaAge Asian and MORPH datasets.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 94
    Publication Date: 2018-09-08
    Description: Symmetry, Vol. 10, Pages 387: Smart Doll: Emotion Recognition Using Embedded Deep Learning Symmetry doi: 10.3390/sym10090387 Authors: Jose Espinosa-Aranda Noelia Vallez Jose Rico-Saavedra Javier Parra-Patino Gloria Bueno Matteo Sorci David Moloney Dexmont Pena Oscar Deniz Computer vision and deep learning are clearly demonstrating a capability to create engaging cognitive applications and services. However, these applications have been mostly confined to powerful Graphic Processing Units (GPUs) or the cloud due to their demanding computational requirements. Cloud processing has obvious bandwidth, energy consumption and privacy issues. The Eyes of Things (EoT) is a powerful and versatile embedded computer vision platform which allows the user to develop artificial vision and deep learning applications that analyse images locally. In this article, we use the deep learning capabilities of an EoT device for a real-life facial informatics application: a doll capable of recognizing emotions, using deep learning techniques, and acting accordingly. The main impact and significance of the presented application is in showing that a toy can now do advanced processing locally, without the need of further computation in the cloud, thus reducing latency and removing most of the ethical issues involved. Finally, the performance of the convolutional neural network developed for that purpose is studied and a pilot was conducted on a panel of 12 children aged between four and ten years old to test the doll.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 95
    Publication Date: 2018-09-08
    Description: Symmetry, Vol. 10, Pages 386: Intersection Traffic Prediction Using Decision Tree Models Symmetry doi: 10.3390/sym10090386 Authors: Walaa Alajali Wei Zhou Sheng Wen Yu Wang Traffic prediction is a critical task for intelligent transportation systems (ITS). Prediction at intersections is challenging as it involves various participants, such as vehicles, cyclists, and pedestrians. In this paper, we propose a novel approach for the accurate intersection traffic prediction by introducing extra data sources other than road traffic volume data into the prediction model. In particular, we take advantage of the data collected from the reports of road accidents and roadworks happening near the intersections. In addition, we investigate two types of learning schemes, namely batch learning and online learning. Three popular ensemble decision tree models are used in the batch learning scheme, including Gradient Boosting Regression Trees (GBRT), Random Forest (RF) and Extreme Gradient Boosting Trees (XGBoost), while the Fast Incremental Model Trees with Drift Detection (FIMT-DD) model is adopted for the online learning scheme. The proposed approach is evaluated using public data sets released by the Victorian Government of Australia. The results indicate that the accuracy of intersection traffic prediction can be improved by incorporating nearby accidents and roadworks information.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 96
    Publication Date: 2018-09-09
    Description: Symmetry, Vol. 10, Pages 389: Asymmetric Firing Rate from Crayfish Left and Right Caudal Photoreceptors Due to Blue and Green Monochromatic Light Pulses Symmetry doi: 10.3390/sym10090389 Authors: Juan C. Sánchez-Hernández José Agustín Pacheco-Ortiz Leonardo Rodríguez-Sosa Gabina Calderón-Rosete Edgar Villagran-Vargas Recent studies have postulated that the left and right caudal photoreceptors (CPR-L and CPR-R, respectively) of the crayfish show asymmetry of spontaneous activity in darkness and responses induced by white light. Two photopigments have been identified; the first one sensitive to blue light and the second one sensitive to green light. This study explores blue and green monochromatic light responsiveness with respect to both CPR-L and -R, as well as the effects of temperature on these photoreceptors. We performed simultaneous extracellular recordings of the firing rate of action potentials from CPRs of the crayfish Cherax quadricarinatus (n = 12). At room temperature (24 ± 1 °C), CPR-L and -R showed a significant difference in the spikes from most of the comparations. CPRs in the dark exhibited spontaneous asymmetric activity and displayed sensitivity to both monochromatic light sources. CPR responses were light intensity dependent within a range of 1.4 logarithmic intensity units, showing approximately 0.5 logarithmic intensity units more sensitivity to blue than to green light. The CPRs displayed an asymmetrical response to both colors by using a constant light intensity. At 14 (±1) °C, activity in darkness diminished while asymmetry persisted, and the CPRs improved responses for both monochromatic light sources, displaying a significant asymmetry. Here, we provide additional evidence of the asymmetric activity in darkness and light response from the CPRs. The new data allow further investigations regarding the physiological role of caudal photoreceptors in the crayfish.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 97
    Publication Date: 2018-09-09
    Description: Symmetry, Vol. 10, Pages 388: Symmetrical Properties of Graph Representations of Genetic Codes: From Genotype to Phenotype Symmetry doi: 10.3390/sym10090388 Authors: Marco V. José Gabriel S. Zamudio It has long been claimed that the mitochondrial genetic code possesses more symmetries than the Standard Genetic Code (SGC). To test this claim, the symmetrical structure of the SGC is compared with noncanonical genetic codes. We analyzed the symmetries of the graphs of codons and their respective phenotypic graph representation spanned by the RNY (R purines, Y pyrimidines, and N any of them) code, two RNA Extended codes, the SGC, as well as three different mitochondrial genetic codes from yeast, invertebrates, and vertebrates. The symmetry groups of the SGC and their corresponding phenotypic graphs of amino acids expose the evolvability of the SGC. Indeed, the analyzed mitochondrial genetic codes are more symmetrical than the SGC.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 98
    Publication Date: 2018-09-13
    Description: Symmetry, Vol. 10, Pages 398: The Gauss Map and the Third Laplace-Beltrami Operator of the Rotational Hypersurface in 4-Space Symmetry doi: 10.3390/sym10090398 Authors: Erhan Güler Hasan Hilmi Hacısalihoğlu Young Ho Kim We study and examine the rotational hypersurface and its Gauss map in Euclidean four-space E 4 . We calculate the Gauss map, the mean curvature and the Gaussian curvature of the rotational hypersurface and obtain some results. Then, we introduce the third Laplace–Beltrami operator. Moreover, we calculate the third Laplace–Beltrami operator of the rotational hypersurface in E 4 . We also draw some figures of the rotational hypersurface.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 99
    Publication Date: 2018-09-13
    Description: Symmetry, Vol. 10, Pages 397: A Reversible Watermarking Scheme for Vector Maps Based on Multilevel Histogram Modification Symmetry doi: 10.3390/sym10090397 Authors: Xiang Hou Lianquan Min Hui Yang To protect the security of vector maps, we propose a novel reversible watermarking scheme for vector maps based on a multilevel histogram modification. First, a difference histogram is constructed using the correlations of adjacent coordinates, and the histogram is divided into continuous regions and discontinuous regions by combining the characteristics of vector map data. Second, the histogram bins that require modification are determined in the continuous regions through the optimal peak value, and the peak values are chosen from the flanking discontinuous regions in both directions; the watermarks are embedded by adopting the multilevel histogram modification strategy. The watermark extraction process is the reverse of the embedding process, and after completing the watermark extraction, the carrier data can be recovered losslessly. The experimental results show that the proposed algorithm has good invisibility and is completely reversible. Compared with similar algorithms reported previously, it achieves higher watermark embedding capacity under the same embedding distortion with lower complexity, thereby having a higher application value.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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  • 100
    Publication Date: 2018-09-16
    Description: Symmetry, Vol. 10, Pages 403: Testing of Grouped Product for the Weibull Distribution Using Neutrosophic Statistics Symmetry doi: 10.3390/sym10090403 Authors: Muhammad Aslam Osama H. Arif Parts manufacturers use sudden death testing to reduce the testing time of experiments. The sudden death testing plan in the literature can only be applied when all observations of failure time/parameters are crisp. In practice however, it is noted that not all measurements of continuous variables are precise. Therefore, the existing sudden death test plan can be applied if failure data/or parameters are imprecise, incomplete, and fuzzy. The classical statistics have the special case of neutrosophic statistics when there are no fuzzy observations/parameters. The neutrosophic fuzzy statistics can be applied for the testing of manufacturing parts when observations are imprecise, incomplete and fuzzy. In this paper, we will design an original neutrosophic fuzzy sudden death testing plan for the inspection/testing of the electronic product or parts manufacturing. We will assume that the lifetime of the product follows the neutrosophic fuzzy Weibull distribution. The neutrosophic fuzzy operating function will be given and used to determine the neutrosophic fuzzy plan parameters through a neutrosophic fuzzy optimization problem. The results of the proposed neutrosophic fuzzy death testing plan will be implemented with the aid of an example.
    Electronic ISSN: 2073-8994
    Topics: Mathematics , Physics
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