Symmetry

13 pages, 4168 KiB

Open AccessArticle

A Numerical Simulation of Silver–Water Nanofluid Flow with Impacts of Newtonian Heating and Homogeneous–Heterogeneous Reactions Past a Nonlinear Stretched Cylinder

by Muhammad Suleman, Muhammad Ramzan, Shafiq Ahmad, Dianchen Lu, Taseer Muhammad and Jae Dong Chung

Symmetry 2019, 11(2), 295; https://doi.org/10.3390/sym11020295 - 24 Feb 2019

Cited by 49 | Viewed by 3879

Abstract

The aim of the present study is to address the impacts of Newtonian heating and homogeneous–heterogeneous (h-h) reactions on the flow of Ag–H2O nanofluid over a cylinder which is stretched in a nonlinear way. The additional effects of magnetohydrodynamics (MHD) and nonlinear thermal [...] Read more.

The aim of the present study is to address the impacts of Newtonian heating and homogeneous–heterogeneous (h-h) reactions on the flow of Ag–H2O nanofluid over a cylinder which is stretched in a nonlinear way. The additional effects of magnetohydrodynamics (MHD) and nonlinear thermal radiation are also added features of the problem under consideration. The Shooting technique is betrothed to obtain the numerical solution of the problem which is comprised of highly nonlinear system ordinary differential equations. The sketches of different parameters versus the involved distributions are given with requisite deliberations. The obtained numerical results are matched with an earlier published work and an excellent agreement exists between both. From our obtained results, it is gathered that the temperature profile is enriched with augmented values radiation and curvature parameters. Additionally, the concentration field is a declining function of the strength of h-h reactions. Full article

(This article belongs to the Special Issue Symmetry and Fluid Mechanics)

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13 pages, 312 KiB

Open AccessArticle

Fixed-Discs in Rectangular Metric Spaces

by Hassen Aydi, Nihal Taş, Nihal Yılmaz Özgür and Nabil Mlaiki

Symmetry 2019, 11(2), 294; https://doi.org/10.3390/sym11020294 - 24 Feb 2019

Cited by 31 | Viewed by 3119

Abstract

In this manuscript, we present some results related to fixed-discs of self-mappings in rectangular metric spaces. To do this, we give new techniques modifying some classical notions such as Banach contraction principle, α-admissible mappings and Brianciari type contractions. We give necessary illustrative [...] Read more.

In this manuscript, we present some results related to fixed-discs of self-mappings in rectangular metric spaces. To do this, we give new techniques modifying some classical notions such as Banach contraction principle, α-admissible mappings and Brianciari type contractions. We give necessary illustrative examples to show the validity of our obtained theoretical theorems. Our results are generalizations of some fixed-circle results existing in the literature. Full article

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21 pages, 3346 KiB

Open AccessArticle

A Secure and Efficient Lightweight Symmetric Encryption Scheme for Transfer of Text Files between Embedded IoT Devices

by Sreeja Rajesh, Varghese Paul, Varun G. Menon and Mohammad R. Khosravi

Symmetry 2019, 11(2), 293; https://doi.org/10.3390/sym11020293 - 24 Feb 2019

Cited by 151 | Viewed by 10207

Abstract

Recent advancements in wireless technology have created an exponential rise in the number of connected devices leading to the internet of things (IoT) revolution. Large amounts of data are captured, processed and transmitted through the network by these embedded devices. Security of the [...] Read more.

Recent advancements in wireless technology have created an exponential rise in the number of connected devices leading to the internet of things (IoT) revolution. Large amounts of data are captured, processed and transmitted through the network by these embedded devices. Security of the transmitted data is a major area of concern in IoT networks. Numerous encryption algorithms have been proposed in these years to ensure security of transmitted data through the IoT network. Tiny encryption algorithm (TEA) is the most attractive among all, with its lower memory utilization and ease of implementation on both hardware and software scales. But one of the major issues of TEA and its numerous developed versions is the usage of the same key through all rounds of encryption, which yields a reduced security evident from the avalanche effect of the algorithm. Also, the encryption and decryption time for text is high, leading to lower efficiency in IoT networks with embedded devices. This paper proposes a novel tiny symmetric encryption algorithm (NTSA) which provides enhanced security for the transfer of text files through the IoT network by introducing additional key confusions dynamically for each round of encryption. Experiments are carried out to analyze the avalanche effect, encryption and decryption time of NTSA in an IoT network including embedded devices. The results show that the proposed NTSA algorithm is much more secure and efficient compared to state-of-the-art existing encryption algorithms. Full article

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14 pages, 273 KiB

Open AccessArticle

Some General Classes of q-Starlike Functions Associated with the Janowski Functions

by Hari M. Srivastava, Muhammad Tahir, Bilal Khan, Qazi Zahoor Ahmad and Nazar Khan

Symmetry 2019, 11(2), 292; https://doi.org/10.3390/sym11020292 - 23 Feb 2019

Cited by 108 | Viewed by 4230

Abstract

By making use of the concept of basic (or q-) calculus, various families of q-extensions of starlike functions of order

α

in the open unit disk

U

were introduced and studied from many different viewpoints and perspectives. In this paper, we [...] Read more.

By making use of the concept of basic (or q-) calculus, various families of q-extensions of starlike functions of order

α

in the open unit disk

U

were introduced and studied from many different viewpoints and perspectives. In this paper, we first investigate the relationship between various known classes of q-starlike functions that are associated with the Janowski functions. We then introduce and study a new subclass of q-starlike functions that involves the Janowski functions. We also derive several properties of such families of q-starlike functions with negative coefficients including (for example) distortion theorems. Full article

(This article belongs to the Special Issue Integral Transforms and Operational Calculus)

13 pages, 10884 KiB

Open AccessArticle

Enhancement of Curve-Fitting Image Compression Using Hyperbolic Function

by Walaa Khalaf, Dhafer Zaghar and Noor Hashim

Symmetry 2019, 11(2), 291; https://doi.org/10.3390/sym11020291 - 23 Feb 2019

Cited by 13 | Viewed by 6009

Abstract

Image compression is one of the most interesting fields of image processing that is used to reduce image size. 2D curve-fitting is a method that converts the image data (pixel values) to a set of mathematical equations that are used to represent the [...] Read more.

Image compression is one of the most interesting fields of image processing that is used to reduce image size. 2D curve-fitting is a method that converts the image data (pixel values) to a set of mathematical equations that are used to represent the image. These equations have a fixed form with a few coefficients estimated from the image which has been divided into several blocks. Since the number of coefficients is lower than the original block pixel size, it can be used as a tool for image compression. In this paper, a new curve-fitting model has been proposed to be derived from the symmetric function (hyperbolic tangent) with only three coefficients. The main disadvantages of previous approaches were the additional errors and degradation of edges of the reconstructed image, as well as the blocking effect. To overcome this deficiency, it is proposed that this symmetric hyperbolic tangent (tanh) function be used instead of the classical 1st- and 2nd-order curve-fitting functions which are asymmetric for reformulating the blocks of the image. Depending on the symmetric property of hyperbolic tangent function, this will reduce the reconstruction error and improve fine details and texture of the reconstructed image. The results of this work have been tested and compared with 1st-order curve-fitting, and standard image compression (JPEG) methods. The main advantages of the proposed approach are: strengthening the edges of the image, removing the blocking effect, improving the Structural SIMilarity (SSIM) index, and increasing the Peak Signal-to-Noise Ratio (PSNR) up to 20 dB. Simulation results show that the proposed method has a significant improvement on the objective and subjective quality of the reconstructed image. Full article

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18 pages, 6902 KiB

Open AccessArticle

Toward Self-Driving Bicycles Using State-of-the-Art Deep Reinforcement Learning Algorithms

by SeungYoon Choi, Tuyen P. Le, Quang D. Nguyen, Md Abu Layek, SeungGwan Lee and TaeChoong Chung

Symmetry 2019, 11(2), 290; https://doi.org/10.3390/sym11020290 - 23 Feb 2019

Cited by 20 | Viewed by 5615

Abstract

In this paper, we propose a controller for a bicycle using the DDPG (Deep Deterministic Policy Gradient) algorithm, which is a state-of-the-art deep reinforcement learning algorithm. We use a reward function and a deep neural network to build the controller. By using the [...] Read more.

In this paper, we propose a controller for a bicycle using the DDPG (Deep Deterministic Policy Gradient) algorithm, which is a state-of-the-art deep reinforcement learning algorithm. We use a reward function and a deep neural network to build the controller. By using the proposed controller, a bicycle can not only be stably balanced but also travel to any specified location. We confirm that the controller with DDPG shows better performance than the other baselines such as Normalized Advantage Function (NAF) and Proximal Policy Optimization (PPO). For the performance evaluation, we implemented the proposed algorithm in various settings such as fixed and random speed, start location, and destination location. Full article

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26 pages, 404 KiB

Open AccessArticle

A Generalized Approach towards Soft Expert Sets via Neutrosophic Cubic Sets with Applications in Games

by Muhammad Gulistan and Nasruddin Hassan

Symmetry 2019, 11(2), 289; https://doi.org/10.3390/sym11020289 - 22 Feb 2019

Cited by 9 | Viewed by 3124

Abstract

Games are considered to be the most attractive and healthy event between nations and peoples. Soft expert sets are helpful for capturing uncertain and vague information. By contrast, neutrosophic set is a tri-component logic set, thus it can deal with uncertain, indeterminate, and [...] Read more.

Games are considered to be the most attractive and healthy event between nations and peoples. Soft expert sets are helpful for capturing uncertain and vague information. By contrast, neutrosophic set is a tri-component logic set, thus it can deal with uncertain, indeterminate, and incompatible information where the indeterminacy is quantified explicitly and truth membership, indeterminacy membership, and falsity membership independent of each other. Subsequently, we develop a combined approach and extend this concept further to introduce the notion of the neutrosophic cubic soft expert sets (NCSESs) by using the concept of neutrosophic cubic soft sets, which is a powerful tool for handling uncertain information in many problems and especially in games. Then we define and analyze the properties of internal neutrosophic cubic soft expert sets (INCSESs) and external neutrosophic cubic soft expert sets (ENCSESs), P-order, P-union, P-intersection, P-AND, P-OR and R-order, R-union, R-intersection, R-AND, and R-OR of NCSESs. The NCSESs satisfy the laws of commutativity, associativity, De Morgan, distributivity, idempotentency, and absorption. We derive some conditions for P-union and P-intersection of two INCSESs to be an INCSES. It is shown that P-union and P-intersection of ENCSESs need not be an ENCSES. The R-union and R-intersection of the INCSESs (resp., ENCSESs) need not be an INCSES (resp. ENCSES). Necessary conditions for the P-union, R-union and R-intersection of two ENCSESs to be an ENCSES are obtained. We also study the conditions for R-intersection and P-intersection of two NCSESs to be an INCSES and ENCSES. Finally, for its applications in games, we use the developed procedure to analyze the cricket series between Pakistan and India. It is shown that the proposed method is suitable to be used for decision-making, and as good as or better when compared to existing models. Full article

(This article belongs to the Special Issue New types of Neutrosophic Set/Logic/Probability, Neutrosophic Over-/Under-/Off-Set, Neutrosophic Refined Set, and their Extension to Plithogenic Set/Logic/Probability, with Applications)

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12 pages, 280 KiB

Open AccessArticle

On Central Complete and Incomplete Bell Polynomials I

by Taekyun Kim, Dae San Kim and Gwan-Woo Jang

Symmetry 2019, 11(2), 288; https://doi.org/10.3390/sym11020288 - 22 Feb 2019

Cited by 21 | Viewed by 3099

Abstract

In this paper, we introduce central complete and incomplete Bell polynomials which can be viewed as generalizations of central Bell polynomials and central factorial numbers of the second kind, and also as ’central’ analogues for complete and incomplete Bell polynomials. Further, some properties [...] Read more.

In this paper, we introduce central complete and incomplete Bell polynomials which can be viewed as generalizations of central Bell polynomials and central factorial numbers of the second kind, and also as ’central’ analogues for complete and incomplete Bell polynomials. Further, some properties and identities for these polynomials are investigated. In particular, we provide explicit formulas for the central complete and incomplete Bell polynomials related to central factorial numbers of the second kind. Full article

(This article belongs to the Special Issue Current Trends in Symmetric Polynomials with their Applications)

14 pages, 273 KiB

Open AccessArticle

Some Subclasses of Uniformly Univalent Functions with Respect to Symmetric Points

by Shahid Mahmood, Hari M. Srivastava and Sarfraz Nawaz Malik

Symmetry 2019, 11(2), 287; https://doi.org/10.3390/sym11020287 - 22 Feb 2019

Cited by 8 | Viewed by 2606

Abstract

This article presents the study of certain analytic functions defined by bounded radius rotations associated with conic domain. Many geometric properties like coefficient estimate, radii problems, arc length, integral representation, inclusion results and growth rate of coefficients of Taylor’s series representation are investigated. [...] Read more.

This article presents the study of certain analytic functions defined by bounded radius rotations associated with conic domain. Many geometric properties like coefficient estimate, radii problems, arc length, integral representation, inclusion results and growth rate of coefficients of Taylor’s series representation are investigated. By varying the parameters in results, several well-known results in literature are obtained as special cases. Full article

(This article belongs to the Special Issue Integral Transforms and Operational Calculus)

30 pages, 10318 KiB

Open AccessArticle

Global Image Thresholding Adaptive Neuro-Fuzzy Inference System Trained with Fuzzy Inclusion and Entropy Measures

by Athanasios Bogiatzis and Basil Papadopoulos

Symmetry 2019, 11(2), 286; https://doi.org/10.3390/sym11020286 - 22 Feb 2019

Cited by 12 | Viewed by 3733

Abstract

Thresholding algorithms segment an image into two parts (foreground and background) by producing a binary version of our initial input. It is a complex procedure (due to the distinctive characteristics of each image) which often constitutes the initial step of other image processing [...] Read more.

Thresholding algorithms segment an image into two parts (foreground and background) by producing a binary version of our initial input. It is a complex procedure (due to the distinctive characteristics of each image) which often constitutes the initial step of other image processing or computer vision applications. Global techniques calculate a single threshold for the whole image while local techniques calculate a different threshold for each pixel based on specific attributes of its local area. In some of our previous work, we introduced some specific fuzzy inclusion and entropy measures which we efficiently managed to use on both global and local thresholding. The general method which we presented was an open and adaptable procedure, it was free of sensitivity or bias parameters and it involved image classification, mathematical functions, a fuzzy symmetrical triangular number and some criteria of choosing between two possible thresholds. Here, we continue this research and try to avoid all these by automatically connecting our measures with the wanted threshold using some Artificial Neural Network (ANN). Using an ANN in image segmentation is not uncommon especially in the domain of medical images. However, our proposition involves the use of an Adaptive Neuro-Fuzzy Inference System (ANFIS) which means that all we need is a proper database. It is a simple and immediate method which could provide researchers with an alternative approach to the thresholding problem considering that they probably have at their disposal some appropriate and specialized data. Full article

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22 pages, 326 KiB

Open AccessArticle

A Generic Framework for Accountable Optimistic Fair Exchange Protocol

by Jia-Ch’ng Loh, Swee-Huay Heng and Syh-Yuan Tan

Symmetry 2019, 11(2), 285; https://doi.org/10.3390/sym11020285 - 22 Feb 2019

Cited by 3 | Viewed by 2589

Abstract

Optimistic Fair Exchange protocol was designed for two parties to exchange in a fair way where an arbitrator always remains offline and will be referred only if any dispute happens. There are various optimistic fair exchange protocols with different security properties in the [...] Read more.

Optimistic Fair Exchange protocol was designed for two parties to exchange in a fair way where an arbitrator always remains offline and will be referred only if any dispute happens. There are various optimistic fair exchange protocols with different security properties in the literature. Most of the optimistic fair exchange protocols satisfy resolution ambiguity where a signature signed by the signer is computational indistinguishable from the one resolved by the arbitrator. Huang et al. proposed the first generic framework for accountable optimistic fair exchange protocol in the random oracle model where it possesses resolution ambiguity and is able to reveal the actual signer when needed. Ganjavi et al. later proposed the first generic framework in the standard model. In this paper, we propose a new generic framework for accountable optimistic fair exchange protocol in the standard model using ordinary signature, convertible undeniable signature, and ring signature scheme as the underlying building blocks. We also provide an instantiation using our proposed generic framework to obtain an efficient pairing-based accountable optimistic fair exchange protocol with short signature. Full article

(This article belongs to the Special Issue Information Technology and Its Applications 2021)

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17 pages, 837 KiB

Open AccessArticle

Extending the Adapted PageRank Algorithm Centrality to Multiplex Networks with Data Using the PageRank Two-Layer Approach

by Taras Agryzkov, Manuel Curado, Francisco Pedroche, Leandro Tortosa and José F. Vicent

Symmetry 2019, 11(2), 284; https://doi.org/10.3390/sym11020284 - 22 Feb 2019

Cited by 19 | Viewed by 4501

Abstract

Usually, the nodes’ interactions in many complex networks need a more accurate mapping than simple links. For instance, in social networks, it may be possible to consider different relationships between people. This implies the use of different layers where the nodes are preserved [...] Read more.

Usually, the nodes’ interactions in many complex networks need a more accurate mapping than simple links. For instance, in social networks, it may be possible to consider different relationships between people. This implies the use of different layers where the nodes are preserved and the relationships are diverse, that is, multiplex networks or biplex networks, for two layers. One major issue in complex networks is the centrality, which aims to classify the most relevant elements in a given system. One of these classic measures of centrality is based on the PageRank classification vector used initially in the Google search engine to order web pages. The PageRank model may be understood as a two-layer network where one layer represents the topology of the network and the other layer is related to teleportation between the nodes. This approach may be extended to define a centrality index for multiplex networks based on the PageRank vector concept. On the other hand, the adapted PageRank algorithm (APA) centrality constitutes a model to obtain the importance of the nodes in a spatial network with the presence of data (both real and virtual). Following the idea of the two-layer approach for PageRank centrality, we can consider the APA centrality under the perspective of a two-layer network where, on the one hand, we keep maintaining the layer of the topological connections of the nodes and, on the other hand, we consider a data layer associated with the network. Following a similar reasoning, we are able to extend the APA model to spatial networks with different layers. The aim of this paper is to propose a centrality measure for biplex networks that extends the adapted PageRank algorithm centrality for spatial networks with data to the PageRank two-layer approach. Finally, we show an example where the ability to analyze data referring to a group of people from different aspects and using different sets of independent data are revealed. Full article

(This article belongs to the Special Issue Symmetry in Complex Systems)

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11 pages, 461 KiB

Open AccessArticle

An Upgraded Version of the Binary Search Space-Structured VQ Search Algorithm for AMR-WB Codec

by Cheng-Yu Yeh and Hung-Hsun Huang

Symmetry 2019, 11(2), 283; https://doi.org/10.3390/sym11020283 - 22 Feb 2019

Cited by 4 | Viewed by 2518

Abstract

Adaptive multi-rate wideband (AMR-WB) speech codecs have been widely used for high speech quality in modern mobile communication systems, e.g., handheld mobile devices. Nevertheless, a major handicap is that a remarkable computational load is required in the vector quantization (VQ) of immittance spectral [...] Read more.

Adaptive multi-rate wideband (AMR-WB) speech codecs have been widely used for high speech quality in modern mobile communication systems, e.g., handheld mobile devices. Nevertheless, a major handicap is that a remarkable computational load is required in the vector quantization (VQ) of immittance spectral frequency (ISF) coefficients of an AMR-WB coding. In view of this, a two-stage search algorithm is presented in this paper as an efficient way to reduce the computational complexity of ISF quantization in AMR-WB coding. At stage 1, an input vector is assigned to a search subspace in an efficient manner using the binary search space-structured VQ (BSS-VQ) algorithm, and a codebook search is performed over the subspace at stage 2 using the iterative triangular inequality elimination (ITIE) approach. Through the use of the codeword rejection mechanisms equipped in both stages, the computational load can be remarkably reduced. As compared with the original version of the BSS-VQ algorithm, the upgraded version provides a computational load reduction of up to 51%. Furthermore, this work is expected to satisfy the energy saving requirement when implemented on an AMR-WB codec of mobile devices. Full article

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11 pages, 699 KiB

Open AccessArticle

Kernel Ridge Regression Model Based on Beta-Noise and Its Application in Short-Term Wind Speed Forecasting

by Shiguang Zhang, Ting Zhou, Lin Sun and Chao Liu

Symmetry 2019, 11(2), 282; https://doi.org/10.3390/sym11020282 - 22 Feb 2019

Cited by 6 | Viewed by 3840

Abstract

The Kernel ridge regression (

K R R

) model aims to find the hidden nonlinear structure in raw data. It makes an assumption that the noise in data satisfies the Gaussian model. However, it was pointed out that the noise in wind [...] Read more.

The Kernel ridge regression (

K R R

) model aims to find the hidden nonlinear structure in raw data. It makes an assumption that the noise in data satisfies the Gaussian model. However, it was pointed out that the noise in wind speed/power forecasting obeys the Beta distribution. The classic regression techniques are not applicable to this case. Hence, we derive the empirical risk loss about the Beta distribution and propose a technique of the kernel ridge regression model based on the Beta-noise (

B N

-

K R R

). The numerical experiments are carried out on real-world data. The results indicate that the proposed technique obtains good performance on short-term wind speed forecasting. Full article

(This article belongs to the Special Issue Information Technology and Its Applications 2021)

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18 pages, 339 KiB

Open AccessArticle

Existence Theory for Nonlinear Third-Order Ordinary Differential Equations with Nonlocal Multi-Point and Multi-Strip Boundary Conditions

by Ahmed Alsaedi, Mona Alsulami, Hari M. Srivastava, Bashir Ahmad and Sotiris K. Ntouyas

Symmetry 2019, 11(2), 281; https://doi.org/10.3390/sym11020281 - 22 Feb 2019

Cited by 10 | Viewed by 2869

Abstract

We investigate the solvability and Ulam stability for a nonlocal nonlinear third-order integro-multi-point boundary value problem on an arbitrary domain. The nonlinearity in the third-order ordinary differential equation involves the unknown function together with its first- and second-order derivatives. Our main results rely [...] Read more.

We investigate the solvability and Ulam stability for a nonlocal nonlinear third-order integro-multi-point boundary value problem on an arbitrary domain. The nonlinearity in the third-order ordinary differential equation involves the unknown function together with its first- and second-order derivatives. Our main results rely on the modern tools of functional analysis and are well illustrated with the aid of examples. An analogue problem involving non-separated integro-multi-point boundary conditions is also discussed. Full article

(This article belongs to the Special Issue Integral Transforms and Operational Calculus)

18 pages, 2202 KiB

Open AccessArticle

A Theory of Autofrettage for Open-Ended, Polar Orthotropic Cylinders

by Marina Rynkovskaya, Sergei Alexandrov and Lihui Lang

Symmetry 2019, 11(2), 280; https://doi.org/10.3390/sym11020280 - 22 Feb 2019

Cited by 8 | Viewed by 3622

Abstract

Autofrettage is a widely used process to enhance the fatigue life of holes. In the theoretical investigation presented in this article, a semi-analytic solution is derived for a polar, orthotropic, open-ended cylinder subjected to internal pressure, followed by unloading. Numerical techniques are only [...] Read more.

Autofrettage is a widely used process to enhance the fatigue life of holes. In the theoretical investigation presented in this article, a semi-analytic solution is derived for a polar, orthotropic, open-ended cylinder subjected to internal pressure, followed by unloading. Numerical techniques are only necessary to solve a linear differential equation and evaluate ordinary integrals. The generalized Hooke’s law connects the elastic portion of strain and stress. The flow theory of plasticity is employed. Plastic yielding is controlled by the Tsai–Hill yield criterion and its associated flow rule. It is shown that using the strain rate compatibility equation facilitates the solution. The general solution takes into account that elastic and plastic properties can be anisotropic. An illustrative example demonstrates the effect of plastic anisotropy on the distribution of stresses and strains, including residual stresses and strain, for elastically isotropic materials. Full article

(This article belongs to the Special Issue Analysis and Design of Structures Made of Plastically Anisotropic Materials)

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25 pages, 1302 KiB

Open AccessEditor’s ChoiceArticle

Biological Bases of Beauty Revisited: The Effect of Symmetry, Averageness, and Sexual Dimorphism on Female Facial Attractiveness

by Alex L. Jones and Bastian Jaeger

Symmetry 2019, 11(2), 279; https://doi.org/10.3390/sym11020279 - 21 Feb 2019

Cited by 73 | Viewed by 22162

Abstract

The factors influencing human female facial attractiveness—symmetry, averageness, and sexual dimorphism—have been extensively studied. However, recent studies, using improved methodologies, have called into question their evolutionary utility and links with life history. The current studies use a range of approaches to quantify how [...] Read more.

The factors influencing human female facial attractiveness—symmetry, averageness, and sexual dimorphism—have been extensively studied. However, recent studies, using improved methodologies, have called into question their evolutionary utility and links with life history. The current studies use a range of approaches to quantify how important these factors actually are in perceiving attractiveness, through the use of novel statistical analyses and by addressing methodological weaknesses in the literature. Study One examines how manipulations of symmetry, averageness, femininity, and masculinity affect attractiveness using a two-alternative forced choice task, finding that increased masculinity and also femininity decrease attractiveness, compared to unmanipulated faces. Symmetry and averageness yielded a small and large effect, respectively. Study Two utilises a naturalistic ratings paradigm, finding similar effects of averageness and masculinity as Study One but no effects of symmetry and femininity on attractiveness. Study Three applies geometric face measurements of the factors and a random forest machine learning algorithm to predict perceived attractiveness, finding that shape averageness, dimorphism, and skin texture symmetry are useful features capable of relatively accurate predictions, while shape symmetry is uninformative. However, the factors do not explain as much variance in attractiveness as the literature suggests. The implications for future research on attractiveness are discussed. Full article

(This article belongs to the Special Issue Fluctuating asymmetry: A predictor of human life history outcomes)

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10 pages, 480 KiB

Open AccessArticle

Hybrid Weighted Arithmetic and Geometric Aggregation Operator of Neutrosophic Cubic Sets for MADM

by Lilian Shi and Yue Yuan

Symmetry 2019, 11(2), 278; https://doi.org/10.3390/sym11020278 - 21 Feb 2019

Cited by 7 | Viewed by 3007

Abstract

Neutrosophic cubic sets (NCSs) can express complex multi-attribute decision-making (MADM) problems with its interval and single-valued neutrosophic numbers simultaneously. The weighted arithmetic average (WAA) and geometric average (WGA) operators are common aggregation operators for handling MADM problems. However, the neutrosophic cubic weighted arithmetic [...] Read more.

Neutrosophic cubic sets (NCSs) can express complex multi-attribute decision-making (MADM) problems with its interval and single-valued neutrosophic numbers simultaneously. The weighted arithmetic average (WAA) and geometric average (WGA) operators are common aggregation operators for handling MADM problems. However, the neutrosophic cubic weighted arithmetic average (NCWAA) and neutrosophic cubic geometric weighted average (NCWGA) operators may result in some unreasonable aggregated values in some cases. In order to overcome the drawbacks of the NCWAA and NCWGA, this paper developed a new neutrosophic cubic hybrid weighted arithmetic and geometric aggregation (NCHWAGA) operator and investigates its suitability and effectiveness. Then, we established a MADM method based on the NCHWAGA operator. Finally, a MADM problem with neutrosophic cubic information was provided to illustrate the application and effectiveness of the proposed method. Full article

(This article belongs to the Special Issue New types of Neutrosophic Set/Logic/Probability, Neutrosophic Over-/Under-/Off-Set, Neutrosophic Refined Set, and their Extension to Plithogenic Set/Logic/Probability, with Applications)

10 pages, 250 KiB

Open AccessArticle

Implicative Neutrosophic Quadruple BCK-Algebras and Ideals

by G. Muhiuddin, Ahmad N. Al-Kenani, Eun Hwan Roh and Young Bae Jun

Symmetry 2019, 11(2), 277; https://doi.org/10.3390/sym11020277 - 21 Feb 2019

Cited by 26 | Viewed by 2661

Abstract

A neutrosophic set is initiated by Smarandache, and it is a novel tool to deal with vagueness considering the truth, indeterminacy and falsity memberships satisfying the condition that their sum is less than 3. The concept of neutrosophic quadruple numbers was introduced by [...] Read more.

A neutrosophic set is initiated by Smarandache, and it is a novel tool to deal with vagueness considering the truth, indeterminacy and falsity memberships satisfying the condition that their sum is less than 3. The concept of neutrosophic quadruple numbers was introduced by Florentin Smarandache. Using this idea, Jun et al. introduced the notion of neutrosophic quadruple

B C K / B C I

-numbers, and studied neutrosophic quadruple

B C K / B C I

-algebras. As a continuation of Jun et al.’s paper, the notion of implicative neutrosophic quadruple

B C K

-algebras is introduced, and several properties are investigated. Given a set Y, conditions for the neutrosophic quadruple Y-set

N_{q} (Y)

to be a neutrosophic quadruple

B C I

-algebra are provided. Conditions for the neutrosophic quadruple Y-set

N_{q} (Y)

to be an implicative neutrosophic quadruple

B C K

-algebra are provided. Given subsets I and J of a

B C K

-algebra Y, conditions for the neutrosophic quadruple

(I, J)

-set

N_{q} (I, J)

to be an implicative ideal of the neutrosophic quadruple

B C K

-algebra

N_{q} (Y)

are discussed. Full article

17 pages, 5338 KiB

Open AccessArticle

Peristaltic Blood Flow of Couple Stress Fluid Suspended with Nanoparticles under the Influence of Chemical Reaction and Activation Energy

by Rahmat Ellahi, Ahmed Zeeshan, Farooq Hussain and A. Asadollahi

Symmetry 2019, 11(2), 276; https://doi.org/10.3390/sym11020276 - 21 Feb 2019

Cited by 161 | Viewed by 6280

Abstract

The present study gives a remedy for the malign tissues, cells, or clogged arteries of the heart by means of permeating a slim tube (i.e., catheter) in the body. The tiny size gold particles drift in free space of catheters having flexible walls [...] Read more.

The present study gives a remedy for the malign tissues, cells, or clogged arteries of the heart by means of permeating a slim tube (i.e., catheter) in the body. The tiny size gold particles drift in free space of catheters having flexible walls with couple stress fluid. To improve the efficiency of curing and speed up the process, activation energy has been added to the process. The modified Arrhenius function and Buongiorno model, respectively, moderate the inclusion of activation energy and nanoparticles of gold. The effects of chemical reaction and activation energy on peristaltic transport of nanofluids are also taken into account. It is found that the golden particles encapsulate large molecules to transport essential drugs efficiently to the effected part of the organ. Full article

(This article belongs to the Special Issue Symmetry and Fluid Mechanics)

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11 pages, 256 KiB

Open AccessArticle

A Single-Valued Neutrosophic Linguistic Combined Weighted Distance Measure and Its Application in Multiple-Attribute Group Decision-Making

by Chengdong Cao, Shouzhen Zeng and Dandan Luo

Symmetry 2019, 11(2), 275; https://doi.org/10.3390/sym11020275 - 21 Feb 2019

Cited by 14 | Viewed by 3815

Abstract

The aim of this paper is to present a multiple-attribute group decision-making (MAGDM) framework based on a new single-valued neutrosophic linguistic (SVNL) distance measure. By unifying the idea of the weighted average and ordered weighted averaging into a single-valued neutrosophic linguistic distance, we [...] Read more.

The aim of this paper is to present a multiple-attribute group decision-making (MAGDM) framework based on a new single-valued neutrosophic linguistic (SVNL) distance measure. By unifying the idea of the weighted average and ordered weighted averaging into a single-valued neutrosophic linguistic distance, we first developed a new SVNL weighted distance measure, namely a SVNL combined and weighted distance (SVNLCWD) measure. The focal characteristics of the devised SVNLCWD are its ability to combine both the decision-makers’ attitudes toward the importance, as well as the weights, of the arguments. Various desirable properties and families of the developed SVNLCWD were contemplated. Moreover, a MAGDM approach based on the SVNLCWD was formulated. Lastly, a real numerical example concerning a low-carbon supplier selection problem was used to describe the superiority and feasibility of the developed approach. Full article

(This article belongs to the Special Issue New types of Neutrosophic Set/Logic/Probability, Neutrosophic Over-/Under-/Off-Set, Neutrosophic Refined Set, and their Extension to Plithogenic Set/Logic/Probability, with Applications)

11 pages, 2555 KiB

Open AccessArticle

The Third and Fourth Kind Pseudo-Chebyshev Polynomials of Half-Integer Degree

by Clemente Cesarano, Sandra Pinelas and Paolo Emilio Ricci

Symmetry 2019, 11(2), 274; https://doi.org/10.3390/sym11020274 - 20 Feb 2019

Cited by 10 | Viewed by 4070

Abstract

New sets of orthogonal functions, which correspond to the first, second, third, and fourth kind Chebyshev polynomials with half-integer indexes, have been recently introduced. In this article, links of these new sets of irrational functions to the third and fourth kind Chebyshev polynomials [...] Read more.

New sets of orthogonal functions, which correspond to the first, second, third, and fourth kind Chebyshev polynomials with half-integer indexes, have been recently introduced. In this article, links of these new sets of irrational functions to the third and fourth kind Chebyshev polynomials are highlighted and their connections with the classical Chebyshev polynomials are shown. Full article

(This article belongs to the Special Issue Numerical Analysis or Numerical Method in Symmetry)

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17 pages, 383 KiB

Open AccessArticle

Data Source Selection Based on an Improved Greedy Genetic Algorithm

by Jian Yang and Chunxiao Xing

Symmetry 2019, 11(2), 273; https://doi.org/10.3390/sym11020273 - 20 Feb 2019

Cited by 7 | Viewed by 4463

Abstract

The development of information technology has led to a sharp increase in data volume. The tremendous amount of data has become a strategic capital that allows businesses to derive superior market intelligence or improve existing operations. People expect to consolidate and utilize data [...] Read more.

The development of information technology has led to a sharp increase in data volume. The tremendous amount of data has become a strategic capital that allows businesses to derive superior market intelligence or improve existing operations. People expect to consolidate and utilize data as much as possible. However, too much data will bring huge integration cost, such as the cost of purchasing and cleaning. Therefore, under the context of limited resources, obtaining more data integration value is our expectation. In addition, the uneven quality of data sources make the multi-source selection task more difficult, and low-quality data sources can seriously affect integration results without the desired quality gain. In this paper, we have studied how to balance data gain and cost in the source selection, specifically, maximizing the gain of data on the premise of a given budget. We proposed an improved greedy genetic algorithm (IGGA) to solve the problem of source selection, and carried out a wide range of experimental evaluations on the real and synthetic dataset. The empirical results show considerable performance in favor of the proposed algorithm in terms of solution quality. Full article

(This article belongs to the Special Issue Information Technology and Its Applications 2021)

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15 pages, 359 KiB

Open AccessArticle

Quantum-Resistant Identity-Based Signature with Message Recovery and Proxy Delegation

by Xiuhua Lu, Qiaoyan Wen, Wei Yin, Kaitai Liang, Zhengping Jin, Emmanouil Panaousis and Jiageng Chen

Symmetry 2019, 11(2), 272; https://doi.org/10.3390/sym11020272 - 20 Feb 2019

Cited by 6 | Viewed by 3126

Abstract

Digital signature with proxy delegation, which is a secure ownership enforcement tool, allows an original signer to delegate signature rights to a third party called proxy, so that the proxy can sign messages on behalf of the original signer. Many real-world applications make [...] Read more.

Digital signature with proxy delegation, which is a secure ownership enforcement tool, allows an original signer to delegate signature rights to a third party called proxy, so that the proxy can sign messages on behalf of the original signer. Many real-world applications make use of this secure mechanism, e.g., digital property transfer. A traditional digital signature mechanism is required to bind a message and its signature together for verification. This may yield extra cost in bandwidth while the sizes of message and signature are relatively huge. Message recovery signature, enabling to reduce the cost of bandwidth, embeds a message into the corresponding signature; therefore, only the signature will be transmitted to the verifier and the message can further be recovered from the signature. In this paper, we, for the first time, propose a novel digital signature scheme in the identity-based context with proxy delegation and message recovery features and, more importantly, our scheme is quantum resistant, in a particular lattice-based signature. Our scheme achieves delegation information and signature existential unforgeability against adaptive chosen warrant and identity. Compared with the seminal lattice-based message recovery signature, our scheme is independent from public key infrastructure, realizes delegation transfer of signature rights, and compresses signature length ulteriorly. To the best of our knowledge, this paper is the first of its type. Full article

(This article belongs to the Special Issue Symmetry and Asymmetry Applications for Internet of Things Security and Privacy)

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10 pages, 499 KiB

Open AccessArticle

Soliton and Breather Splitting on Star Graphs from Tricrystal Josephson Junctions

by Hadi Susanto, Natanael Karjanto, Zulkarnain, Toto Nusantara and Taufiq Widjanarko

Symmetry 2019, 11(2), 271; https://doi.org/10.3390/sym11020271 - 20 Feb 2019

Cited by 8 | Viewed by 3311

Abstract

We consider the interactions of traveling localized wave solutions with a vertex in a star graph domain that describes multiple Josephson junctions with a common/branch point (i.e., tricrystal junctions). The system is modeled by the sine-Gordon equation. The vertex is represented by boundary [...] Read more.

We consider the interactions of traveling localized wave solutions with a vertex in a star graph domain that describes multiple Josephson junctions with a common/branch point (i.e., tricrystal junctions). The system is modeled by the sine-Gordon equation. The vertex is represented by boundary conditions that are determined by the continuity of the magnetic field and vanishing total fluxes. When one considers small-amplitude breather solutions, the system can be reduced into the nonlinear Schrödinger equation posed on a star graph. Using the equation, we show that a high-velocity incoming soliton is split into a transmitted component and a reflected one. The transmission is shown to be in good agreement with the transmission rate of plane waves in the linear Schrödinger equation on the same graph (i.e., a quantum graph). In the context of the sine-Gordon equation, small-amplitude breathers show similar qualitative behaviors, while large-amplitude ones produce complex dynamics. Full article

(This article belongs to the Special Issue Symmetries of Nonlinear PDEs on Metric Graphs and Branched Networks)

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10 pages, 411 KiB

Open AccessArticle

Compression of a Polar Orthotropic Wedge between Rotating Plates: Distinguished Features of the Solution

by Sergei Alexandrov, Elena Lyamina, Pham Chinh and Lihui Lang

Symmetry 2019, 11(2), 270; https://doi.org/10.3390/sym11020270 - 20 Feb 2019

Viewed by 2594

Abstract

An infinite wedge of orthotropic material is confined between two rotating planar rough plates, which are inclined at an angle 2α. An instantaneous boundary value problem for the flow of the material is formulated and solved for the stress and the velocity fields, [...] Read more.

An infinite wedge of orthotropic material is confined between two rotating planar rough plates, which are inclined at an angle 2α. An instantaneous boundary value problem for the flow of the material is formulated and solved for the stress and the velocity fields, the solution being in closed form. The solution may exhibit the regimes of sliding or sticking at the plates. It is shown that the overall structure of the solution significantly depends on the friction stress at sliding. This stress is postulated by the friction law. Solutions, which exhibit sticking, may exist only if the postulated friction stress at sliding satisfies a certain condition. These solutions have a rigid rotating zone in the region adjacent to the plates, unless the angle α is equal to a certain critical value. Solutions which exhibit sliding may be singular. In particular, some space stress and velocity derivatives approach infinity in the vicinity of the friction surface. Full article

(This article belongs to the Special Issue Analysis and Design of Structures Made of Plastically Anisotropic Materials)

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15 pages, 395 KiB

Open AccessArticle

Algebraic Construction of a Strongly Consistent, Permutationally Symmetric and Conservative Difference Scheme for 3D Steady Stokes Flow

by Xiaojing Zhang, Vladimir P. Gerdt and Yury A. Blinkov

Symmetry 2019, 11(2), 269; https://doi.org/10.3390/sym11020269 - 20 Feb 2019

Cited by 6 | Viewed by 2787

Abstract

By using symbolic algebraic computation, we construct a strongly-consistent second-order finite difference scheme for steady three-dimensional Stokes flow and a Cartesian solution grid. The scheme has the second order of accuracy and incorporates the pressure Poisson equation. This equation is the integrability condition [...] Read more.

By using symbolic algebraic computation, we construct a strongly-consistent second-order finite difference scheme for steady three-dimensional Stokes flow and a Cartesian solution grid. The scheme has the second order of accuracy and incorporates the pressure Poisson equation. This equation is the integrability condition for the discrete momentum and continuity equations. Our algebraic approach to the construction of difference schemes suggested by the second and the third authors combines the finite volume method, numerical integration, and difference elimination. We make use of the techniques of the differential and difference Janet/Gröbner bases for performing related computations. To prove the strong consistency of the generated scheme, we use these bases to correlate the differential ideal generated by the polynomials in the Stokes equations with the difference ideal generated by the polynomials in the constructed difference scheme. As this takes place, our difference scheme is conservative and inherits permutation symmetry of the differential Stokes flow. For the obtained scheme, we compute the modified differential system and use it to analyze the scheme’s accuracy. Full article

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12 pages, 268 KiB

Open AccessArticle

Some New q-Congruences for Truncated Basic Hypergeometric Series

by Victor J. W. Guo and Michael J. Schlosser

Symmetry 2019, 11(2), 268; https://doi.org/10.3390/sym11020268 - 20 Feb 2019

Cited by 25 | Viewed by 3164

Abstract

We provide several new q-congruences for truncated basic hypergeometric series, mostly of arbitrary order. Our results include congruences modulo the square or the cube of a cyclotomic polynomial, and in some instances, parametric generalizations thereof. These are established by a variety of [...] Read more.

We provide several new q-congruences for truncated basic hypergeometric series, mostly of arbitrary order. Our results include congruences modulo the square or the cube of a cyclotomic polynomial, and in some instances, parametric generalizations thereof. These are established by a variety of techniques including polynomial argument, creative microscoping (a method recently introduced by the first author in collaboration with Zudilin), Andrews’ multiseries generalization of the Watson transformation, and induction. We also give a number of related conjectures including congruences modulo the fourth power of a cyclotomic polynomial. Full article

13 pages, 257 KiB

Open AccessArticle

Multi-Attribute Decision Making Method Based on Aggregated Neutrosophic Set

by Wen Jiang, Zihan Zhang and Xinyang Deng

Symmetry 2019, 11(2), 267; https://doi.org/10.3390/sym11020267 - 20 Feb 2019

Cited by 10 | Viewed by 3275

Abstract

Multi-attribute decision-making refers to the decision-making problem of selecting the optimal alternative or sorting the scheme when considering multiple attributes, which is widely used in engineering design, economy, management and military, etc. But in real application, the attribute information of many objects is [...] Read more.

Multi-attribute decision-making refers to the decision-making problem of selecting the optimal alternative or sorting the scheme when considering multiple attributes, which is widely used in engineering design, economy, management and military, etc. But in real application, the attribute information of many objects is often inaccurate or uncertain, so it is very important for us to find a useful and efficient method to solve the problem. Neutrosophic set is proposed from philosophical point of view to handle inaccurate information efficiently, and a single-valued neutrosophic set (SVNS) is a special case of neutrosophic set, which is widely used in actual application fields. In this paper, a new method based on single-valued neutrosophic sets aggregation to solve multi-attribute decision making problem is proposed. Firstly, the neutrosophic decision matrix is obtained by expert assessment, a score function of single-valued neutrosophic sets (SVNSs) is defined to obtain the positive ideal solution (PIS) and the negative ideal solution (NIS). Then all alternatives are aggregated based on TOPSIS method to make decision. Finally numerical examples are given to verify the feasibility and rationality of the method. Full article

(This article belongs to the Special Issue New types of Neutrosophic Set/Logic/Probability, Neutrosophic Over-/Under-/Off-Set, Neutrosophic Refined Set, and their Extension to Plithogenic Set/Logic/Probability, with Applications)

20 pages, 6182 KiB

Open AccessArticle

Fast Pig Detection with a Top-View Camera under Various Illumination Conditions

by Jaewon Sa, Younchang Choi, Hanhaesol Lee, Yongwha Chung, Daihee Park and Jinho Cho

Symmetry 2019, 11(2), 266; https://doi.org/10.3390/sym11020266 - 20 Feb 2019

Cited by 30 | Viewed by 5488

Abstract

The fast detection of pigs is a crucial aspect for a surveillance environment intended for the ultimate purpose of the 24 h tracking of individual pigs. Particularly, in a realistic pig farm environment, one should consider various illumination conditions such as sunlight, but [...] Read more.

The fast detection of pigs is a crucial aspect for a surveillance environment intended for the ultimate purpose of the 24 h tracking of individual pigs. Particularly, in a realistic pig farm environment, one should consider various illumination conditions such as sunlight, but such consideration has not been reported yet. We propose a fast method to detect pigs under various illumination conditions by exploiting the complementary information from depth and infrared images. By applying spatiotemporal interpolation, we first remove the noises caused by sunlight. Then, we carefully analyze the characteristics of both the depth and infrared information and detect pigs using only simple image processing techniques. Rather than exploiting highly time-consuming techniques, such as frequency-, optimization-, or deep learning-based detections, our image processing-based method can guarantee a fast execution time for the final goal, i.e., intelligent pig monitoring applications. In the experimental results, pigs could be detected effectively through the proposed method for both accuracy (i.e., 0.79) and execution time (i.e., 8.71 ms), even with various illumination conditions. Full article

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Symmetry, Volume 11, Issue 2 (February 2019) – 173 articles

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