Symmetry

16 pages, 324 KiB

Open AccessArticle

Copula Approach for Dependent Competing Risks of Generalized Half-Logistic Distributions under Accelerated Censoring Data

by Laila A. Al-Essa, Ahmed A. Soliman, Gamal A. Abd-Elmougod and Huda M. Alshanbari

Symmetry 2023, 15(2), 564; https://doi.org/10.3390/sym15020564 - 20 Feb 2023

Cited by 2 | Viewed by 1606

Abstract

In medicals sciences and reliability engineering, the failure of individuals or units (I/Us) occurs due to independent causes of failure. In general, the symmetry between dependent and independent causes of failure is essential to the nature of the problem at hand. In this [...] Read more.

In medicals sciences and reliability engineering, the failure of individuals or units (I/Us) occurs due to independent causes of failure. In general, the symmetry between dependent and independent causes of failure is essential to the nature of the problem at hand. In this study, we considered the accelerated dependent competing risks model when the lifetime of I/Us was modeled using a generalized half-logistic distribution. The data were obtained with respect to constant stress accelerated life tests (ALTs) with a type-II progressive censoring scheme. The dependence structure was formulated using the copula approach (symmetric Archimedean copula). The model parameters were estimated with the maximum likelihood method; only two dependent causes of failure and bivariate Pareto copula functions were proposed. The approximate confidence intervals were constructed using both the asymptotic normality distribution of MLEs and bootstrap techniques. Additionally, an estimator of the reliability of the system under a normal stress level was constructed. The results from the estimation methods were tested by performing a Monte Carlo simulation study. Finally, an analysis of data sets from two stress levels was performed for illustrative purposes. Full article

(This article belongs to the Special Issue Symmetric and Asymmetric Distributions: Theoretical Developments and Applications Ⅲ)

16 pages, 2144 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Intermolecular Interactions in Binary and Ternary Solutions of a Zwitterionic Compound Studied by Solvatochromism

by Dana Ortansa Dorohoi, Dorina Emilia Creanga and Dan Gheorghe Dimitriu

Symmetry 2023, 15(2), 563; https://doi.org/10.3390/sym15020563 - 20 Feb 2023

Viewed by 1610

Abstract

The 1-dithiocarboxy-2-ethoxy-1-(isoquinolin-2-yl)-2-oxoethan-1-ylid (iQTCY) zwitterionic molecule has been studied by computational and spectral means in order to establish some of its structural parameters in the ground electronic state as well as the nature and the strength of its universal and specific interactions with different [...] Read more.

The 1-dithiocarboxy-2-ethoxy-1-(isoquinolin-2-yl)-2-oxoethan-1-ylid (iQTCY) zwitterionic molecule has been studied by computational and spectral means in order to establish some of its structural parameters in the ground electronic state as well as the nature and the strength of its universal and specific interactions with different solvents. The prevalence of the orientation–induction interactions in the diluted solutions of iQTCY in aprotic solvents and the additional specific interactions by hydrogen bonds (HB) in the protic solvents were demonstrated. Three theoretical models were comparatively used to estimate the composition of the first solvation shell of the iQTCY molecule in ternary solutions. The difference between the interaction energies in molecular pairs solute–solvent was computed based on the statistical cell model of ternary solutions of iQTCY in mixtures of water–ethanol and water–methanol. Using the electro-optical parameters computed by the quantum-mechanical technique and the results of the solvatochromic study, the excited state dipole moment of iQTCY was estimated within the limit of the variational method applicable to molecules that show only an absorption electronic spectrum. Full article

(This article belongs to the Collection Feature Papers in Chemistry)

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21 pages, 4307 KiB

Open AccessArticle

Kinematics Modeling and Singularity Analysis of a 6-DOF All-Metal Vibration Isolator Based on Dual Quaternions

by Chao Zheng, Luming Zou, Zhi Zheng and Xin Xue

Symmetry 2023, 15(2), 562; https://doi.org/10.3390/sym15020562 - 20 Feb 2023

Cited by 2 | Viewed by 1867

Abstract

Driven by the need for impact resistance and vibration reduction for mechanical devices in extreme environments, an all-metal vibration isolator with 6-degree-of-freedom (6-DOF) motion that is horizontally symmetrical was developed. Its stiffness and damping ability are provided by oblique springs in symmetrical arrangement [...] Read more.

Driven by the need for impact resistance and vibration reduction for mechanical devices in extreme environments, an all-metal vibration isolator with 6-degree-of-freedom (6-DOF) motion that is horizontally symmetrical was developed. Its stiffness and damping ability are provided by oblique springs in symmetrical arrangement and a metal–rubber elasto-porous damper. The spring is symmetrically distributed in the center axis of the support load surface. It is necessary to investigate the kinematics and the singularity before conducting multi-body dynamics analysis of the vibration isolator. Based on the theory of dual quaternions, the forward kinematics equations of the isolator were successively derived for theoretical kinematics modeling. In addition, an enhanced Broyden numerical iterative algorithm was developed and applied to the numerical solution of the forward kinematics equations of the vibration isolator. Compared with the traditional rotation-matrix method and Newton–Raphson method, the computational efficiency of the enhanced Broyden numerical iterative algorithm was increased by 680% and 290%, respectively. This was due to the enhanced algorithm without the calculations of any inverse matrix and forward kinematics equations. Finally, according to the forward kinematics Jacobian matrix, the position-singularity trajectory at a given orientation and the orientation-singularity space at a given position are calculated, which provides a basis for the algorithm of the 6-DOF vibration isolator to avoid singular positions and orientations. Full article

(This article belongs to the Special Issue Symmetry and Asymmetry in Composite Materials and Its Applications)

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10 pages, 1260 KiB

Open AccessArticle

Gender-Specific Evaluation Following McLaughlin’s Dynamic Muscle Support for Irreversible Facial Paralysis

by Ines Ana Ederer, Lara Kueenzlen, Robert Sader, Klaus Exner, Torsten Schlosshauer, Jens Rothenberger and Ulrich Michael Rieger

Symmetry 2023, 15(2), 561; https://doi.org/10.3390/sym15020561 - 20 Feb 2023

Viewed by 1544

Abstract

Failure of the mimic muscles as a cause of facial nerve paralysis may result in significant asymmetry, which can be addressed by surgical reanimation procedures. Among those, the temporalis muscle transfer as advocated by McLaughlin is a single-stage technique for the dynamic reanimation [...] Read more.

Failure of the mimic muscles as a cause of facial nerve paralysis may result in significant asymmetry, which can be addressed by surgical reanimation procedures. Among those, the temporalis muscle transfer as advocated by McLaughlin is a single-stage technique for the dynamic reanimation of the mouth. Despite increasing research directed at women’s health, the gender-specific differences of this technique have not yet been addressed. Thus, we retrospectively reviewed the medical records of patients who underwent this operation between 2001 and 2021 for gender-specific differences concerning the postoperative outcome. In total, 28 women and 17 men were included. The two cohorts were statistically comparable with respect to etiological characteristics such as age, duration and etiology of paralysis, and preoperative degree of symptoms. After a median follow up of 15 months, restoration of smiling and elevation of the oral commissure was more often achieved among women than men. A statistically significant difference, however, could only be shown for the latter. Resting symmetry was restored in about 50% of both genders. There were no differences concerning postoperative complications or reoperations. The McLaughlin’s dynamic muscle support effectively re-establishes the elevation of the oral commissure and ability to smile among both genders, albeit women tend to be more likely to achieve the desired results. Full article

(This article belongs to the Special Issue Facial Symmetry Surgery: Old, Established and New Techniques)

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19 pages, 440 KiB

Open AccessArticle

On Statistical Modeling Using a New Version of the Flexible Weibull Model: Bayesian, Maximum Likelihood Estimates, and Distributional Properties with Applications in the Actuarial and Engineering Fields

by Walid Emam

Symmetry 2023, 15(2), 560; https://doi.org/10.3390/sym15020560 - 20 Feb 2023

Cited by 5 | Viewed by 1802

Abstract

In this article, we present a new statistical modification of the Weibull model for updating the flexibility, called the generalized Weibull-Weibull distribution. The new modification of the Weibull model is defined and studied in detail. Some mathematical and statistical functions are studied, such [...] Read more.

In this article, we present a new statistical modification of the Weibull model for updating the flexibility, called the generalized Weibull-Weibull distribution. The new modification of the Weibull model is defined and studied in detail. Some mathematical and statistical functions are studied, such as the quantile function, moments, the information generating measure, the Shannon entropy and the information energy. The joint distribution functions of the two marginal univariate models via the Copula model are provided. The unknown parameters are estimated using the maximum likelihood method and Bayesian method via Monte Carlo simulations. The Bayesian approach is discussed using three different loss functions: the quadratic error loss function, the LINEX loss function, and the general entropy loss function. We perform some numerical simulations to show how interesting the theoretical results are. Finally, the practical application of the proposed model is illustrated by analyzing two applications in the actuarial and engineering fields using corporate data to show the elasticity and advantage of the proposed generalized Weibull-Weibull model. The practical applications show that proposed model is very suitable for modeling actuarial and technical data sets and other related fields. Full article

(This article belongs to the Special Issue Symmetric Machine Learning Method Enhanced by Evolutionary Computation and Its Applications in Big Data Analytics)

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17 pages, 778 KiB

Open AccessArticle

A Trapezoidal Fuzzy Number-Based VIKOR Method with Completely Unknown Weight Information

by Guangzheng Liu and Xingang Wang

Symmetry 2023, 15(2), 559; https://doi.org/10.3390/sym15020559 - 20 Feb 2023

Cited by 12 | Viewed by 3404

Abstract

Multi-attribute group decision-making plays an important role in modern politics, economy, culture, and life. The multi-attribute decision-making process is limited by policymakers’ experience, and knowledge of uncertainty factors, such as weight information, is difficult to directly provide. Moreover, many types of complex rescue [...] Read more.

Multi-attribute group decision-making plays an important role in modern politics, economy, culture, and life. The multi-attribute decision-making process is limited by policymakers’ experience, and knowledge of uncertainty factors, such as weight information, is difficult to directly provide. Moreover, many types of complex rescue information are difficult to accurately describe in numerical terms, which reduces the accuracy and objectivity of the decision results, although the fuzzy theory to solve these problems provides a suitable tool. In order to solve the above problems, a new VIKOR decision method based on trapezoidal fuzzy numbers (TFNs) is proposed. Firstly, the expert weight is calculated by the distance measurement method, the criterion weight is calculated by the deviation maximization method, and then the VIKOR method is used to solve the problem. In order to verify the effectiveness and feasibility of this method, it is applied to the emergency alternative selection problem. Finally, the symmetry analysis of the method is carried out by contrast experiment and sensitivity test. Full article

(This article belongs to the Topic Multi-Criteria Decision Making)

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20 pages, 16699 KiB

Open AccessArticle

A Coupling Optimization Method of Vehicle Structure and Restraint System for Occupant Injury Protection in Traffic Accidents

by Danqi Wang, Junyuan Zhang, Tianqi Zhang, Honghao Zhang and Yong Peng

Symmetry 2023, 15(2), 558; https://doi.org/10.3390/sym15020558 - 20 Feb 2023

Cited by 3 | Viewed by 1837

Abstract

Vehicle front-end structure has the characteristic of symmetry. The damage of occupants in the crash process is determined by the combined effect of the front-end structure and the restraint system of the vehicle. In this paper, the coupling relationship and an optimized method [...] Read more.

Vehicle front-end structure has the characteristic of symmetry. The damage of occupants in the crash process is determined by the combined effect of the front-end structure and the restraint system of the vehicle. In this paper, the coupling relationship and an optimized method for the vehicle front-end structure and restraint system are studied based on vehicle crash dynamics, to reduce occupant injury. A fast solution algorithm for occupant motion response was established using a crash analytical model. Then, an occupant response database was established using the algorithm, to analyze the coupling relationship between the crash pulse and the restraint specific stiffness, with respect to the curve shape and parameters. The results showed that the combination of the concave crash pulse and upward restraint stiffness curve was the best coupling. Subsequently, a coupled optimization method of a concave pulse and upward restraint stiffness was proposed and combined with a crash analytical model and genetic algorithm (GA). The crash pulse and restraint stiffness of vehicle crash data from the NHTSA databases were optimized, as an example, to verify the effectiveness of the method. The optimal occupant acceleration was reduced by 44%. In addition, the feasibility of the optimal result is discussed, to provide a reference for occupant injury protection in traffic accidents. Full article

(This article belongs to the Special Issue Advanced Materials, Structures, Symmetrical Design and Mechanism in Mechanical Engineering)

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20 pages, 1789 KiB

Open AccessFeature PaperArticle

Topological Indices, Graph Spectra, Entropies, Laplacians, and Matching Polynomials of n-Dimensional Hypercubes

by Krishnan Balasubramanian

Symmetry 2023, 15(2), 557; https://doi.org/10.3390/sym15020557 - 20 Feb 2023

Cited by 13 | Viewed by 5631

Abstract

We obtain a large number of degree and distance-based topological indices, graph and Laplacian spectra and the corresponding polynomials, entropies and matching polynomials of n-dimensional hypercubes through the use of Hadamard symmetry and recursive dynamic computational techniques. Moreover, computations are used to provide [...] Read more.

We obtain a large number of degree and distance-based topological indices, graph and Laplacian spectra and the corresponding polynomials, entropies and matching polynomials of n-dimensional hypercubes through the use of Hadamard symmetry and recursive dynamic computational techniques. Moreover, computations are used to provide independent numerical values for the topological indices of the 11- and 12-cubes. We invoke symmetry-based recursive Hadamard transforms to obtain the graph and Laplacian spectra of nD-hypercubes and the computed numerical results are constructed for up to 23-dimensional hypercubes. The symmetries of these hypercubes constitute the hyperoctahedral wreath product groups which also pave the way for the symmetry-based elegant computations. These results are used to independently validate the exact analytical expressions that we have obtained for the topological indices as well as graph, Laplacian spectra and their polynomials. We invoke a robust dynamic programming technique to handle the computationally intensive generation of matching polynomials of hypercubes and compute all matching polynomials up to the 6-cube. The distance degree sequence vectors have been obtained numerically for up to 108-dimensional cubes and their frequencies are found to be in binomial distributions akin to the spectra of n-cubes. Full article

(This article belongs to the Collection Feature Papers in Chemistry)

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10 pages, 259 KiB

Open AccessArticle

Minimizing the Gutman Index among Unicyclic Graphs with Given Matching Number

by Weijun Liu and Jiaqiu Wang

Symmetry 2023, 15(2), 556; https://doi.org/10.3390/sym15020556 - 20 Feb 2023

Cited by 2 | Viewed by 1373

Abstract

For a connected graph G with vertex set V, denote by d(v) the degree of vertex v and d(u, v) the distance between u and v. The value [...] Read more.

For a connected graph G with vertex set V, denote by d(v) the degree of vertex v and d(u, v) the distance between u and v. The value

Gut (G) = \sum_{{u, v} \subseteq V} d (u) d (v) d (u, v)

is called the Gutman index of G. Recently, the graph minimizing the Gutman index among unicyclic graphs with pendent edges was characterized. Denoted by

U (n, m)

the set of unicyclic graphs on n vertices with matching number m. Motivated by that work, in this paper, we obtain a sharp lower bound for Gutman index of graphs in

U (n, m)

, and the extremal graph attaining the bound is also obtained. It is worth noticing that all the extremal graphs are of high symmetry, that is, they have large automorphic groups. Full article

(This article belongs to the Special Issue Combinatorics, Discrete Mathematics, Symmetry and Regularity in Graphs, Graph Indices, Graph Parameters and Applications of Graph Theory)

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14 pages, 8711 KiB

Open AccessFeature PaperArticle

Kant’s Modal Asymmetry between Truth-Telling and Lying Revisited

by José F. Fontanari

Symmetry 2023, 15(2), 555; https://doi.org/10.3390/sym15020555 - 20 Feb 2023

Cited by 2 | Viewed by 1670

Abstract

The modal asymmetry between truth-telling and lying refers to the impossibility of a world in which everyone lies, while on the contrary, a world in which everyone tells the truth is possible. This ethical issue is relevant to modern concerns about epistemic security, [...] Read more.

The modal asymmetry between truth-telling and lying refers to the impossibility of a world in which everyone lies, while on the contrary, a world in which everyone tells the truth is possible. This ethical issue is relevant to modern concerns about epistemic security, or the safety of knowledge. The breakdown of epistemic security leads to the erosion of trust and, hence, to an ‘impossible’ world since a willingness to believe in others is essential for the functioning of society. Here, we examine the threat of disinformation to epistemic security using an individual-based model in which individuals are both senders and receivers of signals and are characterized by their credulity and deceptiveness, which are targets of natural selection. The possible worlds are those favored by natural selection. Lies that significantly harm believers lead to the Kantian scenario: trust is completely eroded and the winners of the evolutionary race are incredulous. However, if the lies are not too harmful, our game evolutionary model predicts a world in which the individuals are both credulous and mildly untruthful. These two possible worlds are separated by a discontinuous phase transition in the limit of infinite population size. Full article

(This article belongs to the Special Issue Active Particle Methods toward Modelling Living Systems)

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27 pages, 10672 KiB

Open AccessArticle

Developing a Fast-Processing Novel Algorithm for Contact Analysis of Standard Spur Gears

by Stelian Cazan, Shubrajit Bhaumik, Viorel Paleu and Spiridon Crețu

Symmetry 2023, 15(2), 554; https://doi.org/10.3390/sym15020554 - 19 Feb 2023

Cited by 1 | Viewed by 1751

Abstract

Numerical methods have gained momentum among specific engineering problems that must be solved in such a manner that accuracy and speed are the two most important aspects to consider regarding the output. This paper presents a fast, semi-analytical method (SAM) and original mathematical [...] Read more.

Numerical methods have gained momentum among specific engineering problems that must be solved in such a manner that accuracy and speed are the two most important aspects to consider regarding the output. This paper presents a fast, semi-analytical method (SAM) and original mathematical algorithms to determine the pressure distribution and von Mises stress for spur gears’ meshing teeth. The SAM begins with the Hartnett approach, based on Boussinesq’s equation for the half-space theory of linear elasticity, which implicitly means an infinite width of the gear flank. To simulate more realistic quarter-space conditions, corrections based on virtual mirror pressure are introduced in the computational algorithm. Mathematical surfaces modeling is an important aspect for spur gears as an intermediate stage to determine the pressure distribution and von Mises stress. Shaft misalignment changes the contact problem from symmetric, in which the half- or quarter-space model can be used, to asymmetric. In the latter case, the model must determine the entire contact area. The obtained output is validated by comparisons between our original FEA results and results from the literature using SAMs and FEA. Full article

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10 pages, 291 KiB

Open AccessArticle

Oscillation of Emden–Fowler-Type Differential Equations with Non-Canonical Operators and Mixed Neutral Terms

by Sathish Kumar Marappan, Alanoud Almutairi, Loredana Florentina Iambor and Omar Bazighifan

Symmetry 2023, 15(2), 553; https://doi.org/10.3390/sym15020553 - 19 Feb 2023

Cited by 2 | Viewed by 1528

Abstract

The study of the symmetric properties of differential equations is essential for identifying effective methods for solving them. In this paper, we examine the oscillatory behavior of solutions of Emden–Fowler-type mixed non-linear neutral differential equations with both canonical and non-canonical operators. By utilizing [...] Read more.

The study of the symmetric properties of differential equations is essential for identifying effective methods for solving them. In this paper, we examine the oscillatory behavior of solutions of Emden–Fowler-type mixed non-linear neutral differential equations with both canonical and non-canonical operators. By utilizing integral conditions and the integral averaging method, we present new sufficient conditions to ensure that all solutions are oscillatory. Our results enhance and extend previous findings in the literature and are illustrated with suitable examples to demonstrate their effectiveness. Full article

12 pages, 783 KiB

Open AccessArticle

Correlation of Neutrinoless Double-β Decay Nuclear Matrix Element with E2 Strength

by Changfeng Jiao, Cenxi Yuan and Jiangming Yao

Symmetry 2023, 15(2), 552; https://doi.org/10.3390/sym15020552 - 19 Feb 2023

Cited by 1 | Viewed by 1523

Abstract

We explore the correlation of the neutrinoless double-

β

decay nuclear matrix element (NME) with electric quadrupole (E2) strength in the framework of the Hamiltonian-based generator-coordinate method, which is a configuration-mixing calculation of symmetry-restored intrinsic basis states. The restoration of symmetries [...] Read more.

We explore the correlation of the neutrinoless double-

β

decay nuclear matrix element (NME) with electric quadrupole (E2) strength in the framework of the Hamiltonian-based generator-coordinate method, which is a configuration-mixing calculation of symmetry-restored intrinsic basis states. The restoration of symmetries that are simultaneously broken in the mean-field states allows us to compute the structural and decay properties associated with wave functions characterized by good quantum numbers. Our calculations show a clear anti-correlation between the neutrinoless double-

β

decay NME and the transition rate of the collective quadrupole excitation from the ground state in response to artificial changes of the quadrupole–quadrupole interaction. The anti-correlation is more remarkable in the decay from a weakly deformed parent nucleus to a more deformed grand-daughter nucleus. This interrelation may provide a way to reduce the uncertainty of the nuclear matrix element. Full article

(This article belongs to the Special Issue Symmetry in Nuclear Physics: Model Calculations, Advances and Applications)

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15 pages, 306 KiB

Open AccessArticle

A Morita-Takeuchi Context and Hopf Coquasigroup Galois Coextensions

by Huaiwen Guo and Shuanhong Wang

Symmetry 2023, 15(2), 551; https://doi.org/10.3390/sym15020551 - 18 Feb 2023

Viewed by 1317

Abstract

For H a Hopf quasigroup and C, a left quasi H-comodule coalgebra, we show that the smash coproduct

C ⋊ H

(as a symmetry of smash product) is linked to some quotient coalgebra

Q = C / C H^{* +}

[...] Read more.

For H a Hopf quasigroup and C, a left quasi H-comodule coalgebra, we show that the smash coproduct

C ⋊ H

(as a symmetry of smash product) is linked to some quotient coalgebra

Q = C / C H^{* +}

by a Morita-Takeuchi context (as a symmetry of Morita context). We use the Morita-Takeuchi setting to prove that for finite dimensional H, equivalent conditions for

C / Q

to be a Hopf quasigroup Galois coextension (as a symmetry of Galois extension). In particular, we consider a special case of quasigroup graded coalgebras as an application of our theory. Full article

10 pages, 4739 KiB

Open AccessArticle

Controlling I-V Hysteresis in Al/Pt Bilayer Symmetric SQUIDs at Millikelvin Temperatures

by Dmitry S. Yakovlev, Ivan A. Nazhestkin, Nidzhat G. Ismailov, Sergei V. Egorov, Vladimir N. Antonov and Vladimir L. Gurtovoi

Symmetry 2023, 15(2), 550; https://doi.org/10.3390/sym15020550 - 18 Feb 2023

Cited by 4 | Viewed by 2372

Abstract

We study operation of a superconducting quantum interference devices (SQUIDs) based on a new bilayer material. They can be used for the ultra-sensitive detection of magnetic momentum at temperatures down to milliKelvin range. Typically, thermal origin hysteresis of the symmetric SQUID current-voltage curves [...] Read more.

We study operation of a superconducting quantum interference devices (SQUIDs) based on a new bilayer material. They can be used for the ultra-sensitive detection of magnetic momentum at temperatures down to milliKelvin range. Typically, thermal origin hysteresis of the symmetric SQUID current-voltage curves limits operating temperatures to

T > 0.6 T c

. We used a new bilayer material for SQUID fabrication, namely proximity-coupled superconductor/normal-metal (S/N) bilayers (aluminum 25 nm/platinum 5 nm). Because of the 5 nm Pt-layer, Al/Pt devices show nonhysteretic behavior in a broad temperature range from 20 mK to 0.8 K. Furthermore, the Al/Pt bilayer devices demonstrate an order of magnitude lower critical current compared to the Al devices, which decreases the screening parameter (

β_{L}

) and improves the modulation depth of the critical current by magnetic flux. Operation at lower temperatures reduces thermal noise and increases the SQUID magnetic field resolution. Moreover, we expect strong decrease of two-level fluctuators on the surface of aluminum due to Pt-layer oxidation protection and hence significant reduction of the 1/f noise. Optimized geometry of Al/Pt symmetric SQUIDs is promising for the detection of single-electron spin flip. Full article

(This article belongs to the Special Issue Quantum Dynamics in Josephson Junctions and Symmetry)

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19 pages, 1326 KiB

Open AccessArticle

Thermodynamics of the Acceleration of the Universe in the κ(R, T) Gravity Model

by Archana Dixit, Sanjeev Gupta, Anirudh Pradhan and Aroonkumar Beesham

Symmetry 2023, 15(2), 549; https://doi.org/10.3390/sym15020549 - 18 Feb 2023

Cited by 3 | Viewed by 1856

Abstract

In this article, we examined the behavior of dark energy (DE) and the cosmic acceleration in the framework of

κ (R, T)

gravity in the standard spherically symmetric coordinates

(x^{i})

= [...] Read more.

In this article, we examined the behavior of dark energy (DE) and the cosmic acceleration in the framework of

κ (R, T)

gravity in the standard spherically symmetric coordinates

(x^{i})

=

t, r, θ, ϕ

, a spatially homogeneous and isotropic FLRW space–time. We discovered some remarkable cosmic characteristics in this investigation that are in line with both observations and the accepted

Λ

CDM model. We made two assumptions in order to determine a deterministic solution of the modified field equations (MFEs): (i)

p = γ ρ

, where

γ (1 \geq γ \geq 0)

is a constant, (ii)

Λ

=

β H^{2}

, where

β

is an arbitrary constant. We solved the MFEs and obtained the expression for the Hubble parameter. The depicted model of

κ (R, T)

gravity was taken into consideration when discussing the behavior of the accelerating Universe. In

κ (R, T)

gravity, the statefinder analysis was utilized to distinguish our model from the

Λ

CDM model. The evolution of the cosmos was studied using an effective equation of state (EoS). We investigated the thermodynamic quantities and the generalized energy conditions in order to test the viability of our model. When dominant and weak energy conditions are satisfied, this validates the model; when the strong energy condition is not satisfied, this accelerates the expansion of the Universe. Full article

(This article belongs to the Special Issue Symmetry in Gravity Research)

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22 pages, 1233 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Detecting Heavy Neutral SUSY Higgs Bosons Decaying to Sparticles at the High-Luminosity LHC

by Howard Baer, Vernon Barger, Xerxes Tata and Kairui Zhang

Symmetry 2023, 15(2), 548; https://doi.org/10.3390/sym15020548 - 18 Feb 2023

Cited by 5 | Viewed by 1798

Abstract

In supersymmetry (SUSY) models with low electroweak naturalness (natSUSY), which have been suggested to be the most likely version of SUSY to emerge from the string landscape, higgsinos are expected at the few hundred GeV scale, whilst electroweak gauginos inhabit the TeV scale. [...] Read more.

In supersymmetry (SUSY) models with low electroweak naturalness (natSUSY), which have been suggested to be the most likely version of SUSY to emerge from the string landscape, higgsinos are expected at the few hundred GeV scale, whilst electroweak gauginos inhabit the TeV scale. For TeV-scale heavy neutral SUSY Higgs bosons H and A, as currently required by LHC searches, the dominant decay modes of

H, A

are gaugino plus higgsino provided these decays are kinematically open. The light higgsinos decay to soft particles, so are largely invisible, whilst the gauginos decay to W, Z or h plus missing transverse energy (

\frac{E}{T}

). Thus, we examine the viability of

H, A \to W + \frac{E}{T}

,

Z + \frac{E}{T}

and

h + \frac{E}{T}

signatures at the high luminosity LHC (HL-LHC) in light of large standard model (SM) backgrounds from (mainly)

t \bar{t}

,

V V

and

V h

production (where

V = W, Z

). We also examine whether these signal channels can be enhanced over backgrounds by requiring the presence of an additional soft lepton from the decays of the light higgsinos. We find significant regions in the vicinity of

m_{A} \sim 1 - 2

TeV of the

m_{A}

vs.

tan β

plane, which can be probed at the high luminosity LHC, using these dominant signatures by HL-LHC at

5 σ

and at the 95% confidence level (CL). Full article

(This article belongs to the Special Issue Supersymmetry with Higgs Bosons Research)

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26 pages, 6414 KiB

Open AccessArticle

Design and Development of a Geometric Calculator in CATIA

by José Ignacio Rojas-Sola, Gloria del Río-Cidoncha, Rafael Ortíz-Marín and Andrés Cebolla-Cano

Symmetry 2023, 15(2), 547; https://doi.org/10.3390/sym15020547 - 18 Feb 2023

Viewed by 2389

Abstract

In this article, an application in the field of engineering graphics is presented for the design of a geometric calculator generated as a macro in CATIA V5. The code of this macro is written in the CATVBA language and utilizes the CATIA internal [...] Read more.

In this article, an application in the field of engineering graphics is presented for the design of a geometric calculator generated as a macro in CATIA V5. The code of this macro is written in the CATVBA language and utilizes the CATIA internal editor while taking advantage of the capabilities offered by Visual Basic for Applications (VBA). The principal purpose of this application lies in the possibility of creating the three main geometric elements (point, line, and plane) and in solving five types of general geometric problems, and then comparing the results obtained with their equivalent problems from analytical geometry. In particular, within these types of general geometric problems, 34 possible cases are solved: definition of lines (nine cases), definition of planes (12 cases), intersection points (three cases), angles (three cases), and distances (seven cases). These new entities defined with the geometric calculator can serve as support for the generation of new three-dimensional volumes, the creation of auxiliary symmetries, and the dimensioning of various elements. It was verified that the results of the designed macro and the solutions of the analytical equations coincided; therefore, the procedure was validated. Likewise, the module employed herein in the CATIA V5 environment is “Wireframe and Surface Design”, since it enables handling the three basic geometric elements (point, line, and plane), which form the basis of the geometric calculator. Lastly, it is verified how the geometric calculator allows their integration with three-dimensional solids, which represents a notable advance as an aid in its geometric definition. Full article

(This article belongs to the Special Issue Advances on Engineering Graphics: Improvements and New Proposals, Volume 2)

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14 pages, 8496 KiB

Open AccessArticle

Spectral-Spatial Feature Enhancement Algorithm for Nighttime Object Detection and Tracking

by Yan Lv, Wei Feng, Shuo Wang, Gabriel Dauphin, Yali Zhang and Mengdao Xing

Symmetry 2023, 15(2), 546; https://doi.org/10.3390/sym15020546 - 17 Feb 2023

Cited by 2 | Viewed by 2190

Abstract

Object detection and tracking has always been one of the important research directions in computer vision. The purpose is to determine whether the object is contained in the input image and enclose the object with a bounding box. However, most object detection and [...] Read more.

Object detection and tracking has always been one of the important research directions in computer vision. The purpose is to determine whether the object is contained in the input image and enclose the object with a bounding box. However, most object detection and tracking methods are applied to daytime objects, and the processing of nighttime objects is imprecise. In this paper, a spectral-spatial feature enhancement algorithm for nighttime object detection and tracking is proposed, which is inspired by symmetrical neural networks. The proposed method consists of the following steps. First, preprocessing is performed on unlabeled nighttime images, including low-light enhancement, object detection, and dynamic programming. Second, object features for daytime and nighttime times are extracted and modulated with a domain-adaptive structure. Third, the Siamese network can make full use of daytime and nighttime object features, which is trained as a tracker by the above images. Fourth, the test set is subjected to feature enhancement and then input to the tracker to obtain the final detection and tracking results. The feature enhancement step includes low-light enhancement and Gabor filtering. The spatial-spectral features of the target are fully extracted in this step. The NAT2021 dataset is used in the experiments. Six methods are employed as comparisons. Multiple judgment indicators were used to analyze the research results. The experimental results show that the method achieves excellent detection and tracking performance. Full article

(This article belongs to the Special Issue Asymmetric and Symmetric Study on Image Processing and Statistical Data Analysis)

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23 pages, 5248 KiB

Open AccessArticle

Machine Learning Approach for Prediction of Lateral Confinement Coefficient of CFRP-Wrapped RC Columns

by Xingsi Xue, Celestine Makota, Osamah Ibrahim Khalaf, Jagan Jayabalan, Pijush Samui and Ghaida Muttashar Abdulsahib

Symmetry 2023, 15(2), 545; https://doi.org/10.3390/sym15020545 - 17 Feb 2023

Cited by 13 | Viewed by 2451

Abstract

Materials have a significant role in creating structures that are durable, valuable and possess symmetry engineering properties. Premium quality materials establish an exemplary environment for every situation. Among the composite materials in constructions, carbon fiber reinforced polymer (CFRP) is one of best materials [...] Read more.

Materials have a significant role in creating structures that are durable, valuable and possess symmetry engineering properties. Premium quality materials establish an exemplary environment for every situation. Among the composite materials in constructions, carbon fiber reinforced polymer (CFRP) is one of best materials which provides symmetric superior strength and stiffness to reinforced concrete structures. For the structure to be confining, the region jeopardizes seismic loads and axial force, specifically on columns, with limited proportion of ties or stirrups implemented to loftier ductility and brittleness. The failure and buckling of columns with CFRP has been studied by many researchers and is ongoing to determine ways columns can be retrofitted. This article symmetrically integrates two disciplines, specifically materials (CFRP) and computer application (machine learning). Technically, predicting the lateral confinement coefficient (K_s) for reinforced concrete columns in designs plays a vital role. Therefore, machine learning models like genetic programming (GP), minimax probability machine regression (MPMR) and deep neural networks (DNN) were utilized to determine the K_s value of CFRP-wrapped RC columns. In order to compute Ks value, parameters such as column width, length, corner radius, thickness of CFRP, compressive strength of the unconfined concrete and elastic modulus of CFRP act as stimulants. The adopted machine learning models utilized 293 datasets of square and rectangular RC columns for the prediction of K_s. Among the developed models, GP and MPMR provide encouraging performances with higher R values of 0.943 and 0.941; however, the statistical indices proved that the GP model outperforms other models with better precision (R² = 0.89) and less errors (RMSE = 0.056 and NMBE = 0.001). Based on the evaluation of statistical indices, rank analysis was carried out, in which GP model secured more points and ranked top. Full article

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10 pages, 2168 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

A Study on the Intersection of Ground Reaction Forces during Overground Walking in Down Syndrome: Effects of the Pathology and Left–Right Asymmetry

by Johanna Vielemeyer, Cristina Sole, Manuela Galli, Matteo Zago, Roy Müller and Claudia Condoluci

Symmetry 2023, 15(2), 544; https://doi.org/10.3390/sym15020544 - 17 Feb 2023

Cited by 4 | Viewed by 4102

Abstract

Motor dysfunctions in patients with Down Syndrome (DS) result in poor locomotion and an altered gait phenotype, characterized by compromised stability management and frequent bilateral asymmetries. Directing ground reaction forces to a point above the center of mass, referred to as the virtual [...] Read more.

Motor dysfunctions in patients with Down Syndrome (DS) result in poor locomotion and an altered gait phenotype, characterized by compromised stability management and frequent bilateral asymmetries. Directing ground reaction forces to a point above the center of mass, referred to as the virtual pivot point (VPP), is one means of maintaining stability during walking. This cross-sectional observational study compared the dynamic gait function of 33 individuals with DS (mean age: 17.7 ± 6.4 years, 13 females) to a group of 36 healthy controls (mean age: 15.5 ± 6.1 years, 15 females), using the concept of the VPP. Results showed that the VPP was located more anteriorly in individuals with DS compared to healthy controls, with no differences in the variability (R²) or symmetry of VPP coordinates. This anterior VPP position is likely due to the larger hip moments observed in patients with DS during the propulsive phase of stance. High R² values in DS suggest that the VPP is strongly related to dynamic stability during walking. Full article

(This article belongs to the Special Issue Biology and Symmetry/Asymmetry：Feature Papers 2022)

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13 pages, 1023 KiB

Open AccessFeature PaperArticle

Post-Inflationary Production of Dark Matter after Inflection Point Slow Roll Inflation

by Anish Ghoshal, Gaetano Lambiase, Supratik Pal, Arnab Paul and Shiladitya Porey

Symmetry 2023, 15(2), 543; https://doi.org/10.3390/sym15020543 - 17 Feb 2023

Cited by 3 | Viewed by 1523

Abstract

We explore a feasible model that combines near-inflection point small-field slow roll inflationary scenario driven by single scalar inflaton with the production of non-thermal vector-like fermionic dark matter,

χ

, during the reheating era. For the inflationary scenario, we consider two separate polynomial [...] Read more.

We explore a feasible model that combines near-inflection point small-field slow roll inflationary scenario driven by single scalar inflaton with the production of non-thermal vector-like fermionic dark matter,

χ

, during the reheating era. For the inflationary scenario, we consider two separate polynomial forms of the potential; one is symmetric about the origin, and the other is not. We fix the coefficients of the potentials satisfying current Planck-Bicep data. We calculate the permissible range of

y_{χ}

and

m_{χ}

for the production of enough dark matter to explain the total Cold Dark Matter (CDM) mass density of the present universe while satisfying Cosmic Background Radiation (CMBR) measurements and other cosmological bounds. Full article

(This article belongs to the Special Issue Symmetry beyond the Standard Models of Cosmology, High Energy Physics and Quantum Field Theory)

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15 pages, 618 KiB

Open AccessArticle

Analysis of the Competition System Using Parameterized Fractional Differential Equations: Application to Real Data

by Mahmoud H. DarAssi, Muhammad Altaf Khan, Fatmawati and Marei Saeed Alqarni

Symmetry 2023, 15(2), 542; https://doi.org/10.3390/sym15020542 - 17 Feb 2023

Cited by 2 | Viewed by 1709

Abstract

Natural symmetries exist in several processes of chemistry, physics, and biology. Symmetries possess interesting dynamical characteristics that cannot be seen in non-symmetric systems. The present paper investigates the competition between two banking systems, rural and commercial, in Indonesia, in parameterized fractional order Caputo [...] Read more.

Natural symmetries exist in several processes of chemistry, physics, and biology. Symmetries possess interesting dynamical characteristics that cannot be seen in non-symmetric systems. The present paper investigates the competition between two banking systems, rural and commercial, in Indonesia, in parameterized fractional order Caputo derivative. A novel numerical method is used to discretize the competition system using the real data of rural and commercial banks in Indonesia for the period 2004–2014. The new scheme is more suitable and reliable for data fitting results and has good accuracy. The integer model is formulated in Caputo derivative and their stability results are presented. With the available parameters, the data for the model is analyzed using various scenarios. We shall compare the result with the previous method used in the literature and show that the present method is better than the previous method in the literature. It is shown that fractional order

α

and the parameter

ρ

involved in the numerical scheme provide excellent fitting. Full article

(This article belongs to the Special Issue Mathematical Modeling of the Infectious Diseases and Their Controls)

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14 pages, 671 KiB

Open AccessArticle

QCD Matter and Phase Transitions under Extreme Conditions

by Mei Huang and Pengfei Zhuang

Symmetry 2023, 15(2), 541; https://doi.org/10.3390/sym15020541 - 17 Feb 2023

Cited by 4 | Viewed by 2354

Abstract

The interplay of chiral dynamics and gluodynamics plays an essential role in the nonperturbative QCD region, and the chiral phase transition and deconfinement phase transition are the main topics of QCD phase transitions under extreme conditions, e.g., finite temperature and/or baryon density, strong [...] Read more.

The interplay of chiral dynamics and gluodynamics plays an essential role in the nonperturbative QCD region, and the chiral phase transition and deconfinement phase transition are the main topics of QCD phase transitions under extreme conditions, e.g., finite temperature and/or baryon density, strong magnetic fields, and fast rotation. We briefly introduce our own recent progress from the theoretical side on QCD phase transitions and phase diagrams under extreme conditions related to the early universe, compact stars, and heavy-ion collisions. Full article

(This article belongs to the Special Issue Heavy-Ion Collisions and Multiparticle Production)

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21 pages, 8691 KiB

Open AccessFeature PaperArticle

Advanced Materials Based on Azulenyl-Phenyloxazolone

by Alina-Giorgiana Brotea, Ovidiu-Teodor Matica, Cornelia Musina (Borsaru), Mihaela Cristea, Amalia Stefaniu, Andreea-Madalina Pandele and Eleonora-Mihaela Ungureanu

Symmetry 2023, 15(2), 540; https://doi.org/10.3390/sym15020540 - 17 Feb 2023

Cited by 2 | Viewed by 1613

Abstract

Chemically modified electrodes (CMEs) based on 2-phenyl-4-((4,6,8-trimethylazulen-1-yl)methylene)oxazol-5(4H)-one (M) were obtained by irreversible electrooxidation of M in millimolar solutions in 0.1 M tetrabutylammonium perchlorate (TBAP) in acetonitrile. These CMEs were characterized by a ferrocene redox probe, electrochemical impedance spectroscopy (EIS), X-ray photon [...] Read more.

Chemically modified electrodes (CMEs) based on 2-phenyl-4-((4,6,8-trimethylazulen-1-yl)methylene)oxazol-5(4H)-one (M) were obtained by irreversible electrooxidation of M in millimolar solutions in 0.1 M tetrabutylammonium perchlorate (TBAP) in acetonitrile. These CMEs were characterized by a ferrocene redox probe, electrochemical impedance spectroscopy (EIS), X-ray photon spectroscopy (XPS), and scanning electron microscopy (SEM). The influence of the preparation conditions (charge and potential) was examined. The CMEs were finally used for the analysis of synthetic samples of heavy metal (HM) ions. The paper highlights the importance of potential and electropolymerization charge on the film properties, with accent on recognition of HMs, in order to identify the best conditions for their detection in water. The observed findings are relevant for further design and development of advanced materials based on azulenyl-phenyloxazolone for the analysis of HMs in water. Full article

(This article belongs to the Section Chemistry: Symmetry/Asymmetry)

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18 pages, 2254 KiB

Open AccessFeature PaperArticle

Electronic and Optical Properties of Alkaline Earth Metal Fluoride Crystals with the Inclusion of Many-Body Effects: A Comparative Study on Rutile MgF₂ and Cubic SrF₂

by Giancarlo Cappellini, Jürgen Furthmüller, Friedhelm Bechstedt and Silvana Botti

Symmetry 2023, 15(2), 539; https://doi.org/10.3390/sym15020539 - 17 Feb 2023

Cited by 4 | Viewed by 1911

Abstract

We conducted a systematic investigation using state-of-the-art techniques on the electronic and optical properties of two crystals of alkaline earth metal fluorides, namely rutile MgF

_{2}

and cubic SrF

_{2}

. For these two crystals of different symmetry, we present density functional theory [...] Read more.

We conducted a systematic investigation using state-of-the-art techniques on the electronic and optical properties of two crystals of alkaline earth metal fluorides, namely rutile MgF

_{2}

and cubic SrF

_{2}

. For these two crystals of different symmetry, we present density functional theory (DFT), many-body perturbation theory (MBPT), and Bethe–Salpeter equation (BSE) calculations. We calculated a variety of properties, namely ground-state energies, band-energy gaps, and optical absorption spectra with the inclusion of excitonic effects. The quantities were obtained with a high degree of convergence regarding all bulk electronic and optical properties. Bulk rutile MgF

_{2}

has distinguished ground-state and excited-state properties with respect to the other cubic fluoride SrF

_{2}

and the other members of the alkaline earth metal fluoride family. The nature of the fundamental gaps and estimates of the self-energy and excitonic effects for the two compounds are presented and discussed in detail. Our results are in good accordance with the measurements and other theoretical–computational data. A comparison is made between the excitation and optical properties of bulk rutile MgF

_{2}

, cubic SrF

_{2}

, and the corresponding clusters, for which calculations have recently been published, confirming strong excitonic effects in finite-sized systems. Full article

(This article belongs to the Special Issue Advances in Optics and Symmetry/Asymmetry)

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17 pages, 453 KiB

Open AccessArticle

A Survey on Resource Management for Cloud Native Mobile Computing: Opportunities and Challenges

by Shih-Yun Huang, Cheng-Yu Chen, Jen-Yeu Chen and Han-Chieh Chao

Symmetry 2023, 15(2), 538; https://doi.org/10.3390/sym15020538 - 17 Feb 2023

Cited by 12 | Viewed by 4678

Abstract

Fifth-generation mobile communication networks (5G)/Beyond 5G (B5G) can achieve higher data rates, more significant connectivity, and lower latency to provide various mobile computing service categories, of which enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable and low latency communications (URLLC) are [...] Read more.

Fifth-generation mobile communication networks (5G)/Beyond 5G (B5G) can achieve higher data rates, more significant connectivity, and lower latency to provide various mobile computing service categories, of which enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable and low latency communications (URLLC) are the three extreme cases. A symmetrically balanced mechanism must be considered in advance to fit the different requirements of such a wide variety of service categories and ensure that the limited resource capacity has been properly allocated. Therefore, a new network service architecture with higher flexibility, dispatchability, and symmetrical adaptivity is demanded. The cloud native architecture that enables service providers to build and run scalable applications/services is highly favored in such a setting, while a symmetrical resource allocation is still preserved. The microservice function in the cloud native architecture can further accelerate the development of various services in a 5G/B5G mobile wireless network. In addition, each microservice part can handle a dedicated service, making overall network management easier. There have been many research and development efforts in the recent literature on topics pertinent to cloud native, such as containerized provisioning, network slicing, and automation. However, there are still some problems and challenges ahead to be addressed. Among them, optimizing resource management for the best performance is fundamentally crucial given the challenge that the resource distribution in the cloud native architecture may need more symmetry. Thus, this paper will survey cloud native mobile computing, focusing on resource management issues of network slicing and containerization. Full article

(This article belongs to the Special Issue Deep Learning Technologies for Mobile Networks: A Themed Issue in Honor of Prof. Han-Chieh Chao)

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37 pages, 20494 KiB

Open AccessArticle

Gravitational Waves and Electromagnetic Radiation from Charged Black Hole Binaries

by Carlos A. Benavides-Gallego and Wen-Biao Han

Symmetry 2023, 15(2), 537; https://doi.org/10.3390/sym15020537 - 17 Feb 2023

Cited by 4 | Viewed by 2037

Abstract

In this manuscript, we investigate the electromagnetic radiation of a binary system of electrically charged black holes. Using the results of previous works, we compute the analytical expression for the waveform, the phase, and the Fourier transform during the inspiral phase for both [...] Read more.

In this manuscript, we investigate the electromagnetic radiation of a binary system of electrically charged black holes. Using the results of previous works, we compute the analytical expression for the waveform, the phase, and the Fourier transform during the inspiral phase for both the electromagnetic and gravitational radiations. To do so, we consider the quasi-circular approximation and small values for the charge-to-mass ratio in each black hole. In the case of electromagnetic radiation, we focus on the dipole contribution, but we also include the quadrupole term to complete our discussion. We found that the gravitational and electromagnetic waveforms contain two terms, and so does the Fourier transform. However, the behavior is dominated only by one of them. In the frequency-domain waves, for example, the dipole and quadrupole contributions and the gravitational wave are dominated by terms proportional to f^−3/6, f^−1/6, and f^−7/6, respectively. As expected, the gravitational radiation and the quadrupole contribution have the same phase, in contrast to the dipole contribution. Moreover, the electromagnetic wave is more sensitive to changes in the charge-to-mass ratio than the gravitational wave. Full article

(This article belongs to the Special Issue Symmetry in Gravity Research)

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17 pages, 787 KiB

Open AccessFeature PaperArticle

Semilocal Convergence of a Multi-Step Parametric Family of Iterative Methods

by Eva G. Villalba, Eulalia Martínez and Paula Triguero-Navarro

Symmetry 2023, 15(2), 536; https://doi.org/10.3390/sym15020536 - 17 Feb 2023

Viewed by 1683

Abstract

In this paper, we deal with a new family of iterative methods for approximating the solution of nonlinear systems for non-differentiable operators. The novelty of this family is that it is a m-step generalization of the Steffensen-type method by updating the divided [...] Read more.

In this paper, we deal with a new family of iterative methods for approximating the solution of nonlinear systems for non-differentiable operators. The novelty of this family is that it is a m-step generalization of the Steffensen-type method by updating the divided difference operator in the first two steps but not in the following ones. This procedure allows us to increase both the order of convergence and the efficiency index with respect to that obtained in the family that updates divided differences only in the first step. We perform a semilocal convergence study that allows us to fix the convergence domain and uniqueness for real applied problems, where the existence of a solution is not known a priori. After this study, some numerical tests are developed to apply the semilocal convergence theoretical results obtained. Finally, mediating the dynamic planes generated by the different numerical methods that compose the family, we study the symmetry of the basins of attraction generated by each solution, the shape of these basins, and the convergence to each root of a polynomial function. Full article

(This article belongs to the Special Issue Nonlinear Analysis and Applications, Geometry of Banach Spaces and Symmetry II)

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29 pages, 4188 KiB

Open AccessReview

Pattern Recognition and Deep Learning Technologies, Enablers of Industry 4.0, and Their Role in Engineering Research

by Joel Serey, Miguel Alfaro, Guillermo Fuertes, Manuel Vargas, Claudia Durán, Rodrigo Ternero, Ricardo Rivera and Jorge Sabattin

Symmetry 2023, 15(2), 535; https://doi.org/10.3390/sym15020535 - 17 Feb 2023

Cited by 27 | Viewed by 7878

Abstract

The purpose of this study is to summarize the pattern recognition (PR) and deep learning (DL) artificial intelligence methods developed for the management of data in the last six years. The methodology used for the study of documents is a content analysis. For [...] Read more.

The purpose of this study is to summarize the pattern recognition (PR) and deep learning (DL) artificial intelligence methods developed for the management of data in the last six years. The methodology used for the study of documents is a content analysis. For this study, 186 references are considered, from which 120 are selected for the literature review. First, a general introduction to artificial intelligence is presented, in which PR/DL methods are studied and their relevance to data management evaluated. Next, a literature review is provided of the most recent applications of PR/DL, and the capacity of these methods to process large volumes of data is evaluated. The analysis of the literature also reveals the main applications, challenges, approaches, advantages, and disadvantages of using these methods. Moreover, we discuss the main measurement instruments; the methodological contributions by study areas and research domain; and major databases, journals, and countries that contribute to the field of study. Finally, we identify emerging research trends, their limitations, and possible future research paths. Full article

(This article belongs to the Section Engineering and Materials)

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