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The article Wave propagation characteristics of the electrically GNP reinforced nanocomposite cylindrical shell, written by Hamed Safarpour, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 12/04/2019 with open access. With the author(s)’ decision to step back from Open Choice, the copyright of the article changed on [07/05/2019] to © The Brazilian Society of Mechanical Sciences and Engineering 2019 and the article is forthwith distributed under the terms of copyright  

In this article, wave propagation characteristics of a size-dependent graphene nanoplatelet (GNP) reinforced composite cylindrical nanoshell coupled with piezoelectric actuator (PIAC) and surrounded with viscoelastic foundation is presented. The effects of small scale are analyzed based on nonlocal strain gradient theory (NSGT) which is an accurate theory employing exact length scale parameter and nonlocal constant. The governing equations of the GNP composite cylindrical nanoshell coupled with PIAC have been evolved using Hamilton’s principle and solved with assistance of the analytical method. For the first time in the current study, wave propagation electrical behavior of a GNP composite... 

In this research, buckling and vibrational characteristics of a spinning cylindrical moderately thick shell covered with piezoelectric actuator carrying spring-mass systems are performed. This structure rotates about axial direction and the formulations include the Coriolis and centrifugal effects. In addition, various cases of thermal (uniform, linear, and nonlinear) distributions are studied. The modeled cylindrical moderately thick shell covered with piezoelectric actuator, its equations of motion, and boundary conditions are derived by the Hamilton's principle and based on a moderately cylindrical thick shell theory. For the first time in the present study, attached mass-spring systems... 

In this research, electrically performance, vibration/resonance characteristics, low-velocity impact, and absorbed energy of the piezoelectric doubly curved panel on the viscoelastic substrate is carried out. For modeling the contact force between the structure and impactor, Hertz contact theory is presented. Hamilton's principle and first-order shear deformation theory (FSDT) are presented for obtaining the governing and boundary condition equations of the structure under the low-velocity impact. Galerkin and Newmark solution procedures are presented for solving the governing equation in displacement, and time domains, respectively. This study's novelty is considering the effect of... 

Networks-on-Chip (NoCs for short) are known as the most scalable and reliable on-chip communication architectures for multi-core SoCs with tens to hundreds IP cores. Proper mapping the IP cores on NoC tiles (or assigning threads to cores in chip multiprocessors) can reduce end-to-end delay and energy consumption. While almost all previous works on mapping consider higher priority for the application's flows with higher required bandwidth, a mapping strategy, presented in this paper, is introduced that considers multicast communication flows in addition to the normal unicast flows. To this end, multicast and unicast traffic flows are first characterized in terms of some new metrics which are... 

The capability of fuzzy systems to solve different kinds of problems has been demonstrated in several previous investigations. Genetic fuzzy systems (GFSs) hybridize the approximate reasoning method of fuzzy systems with the learning capability of evolutionary algorithms. The objective of this paper is to design and analysis of various kinds of genetic fuzzy systems to deal with intrusion detection problem as a new real-world application area which is not previously tackled with GFSs. The resulted intrusion detection system would be capable of detecting normal and abnormal behaviors in computer networks. We have presented three kinds of genetic fuzzy systems based on Michigan, Pittsburgh and... 

Networks-on-Chip (NoCs for short) are known as the most scalable and reliable on-chip communication architectures for multi-core SoCs with tens to hundreds IP cores. Proper mapping the IP cores on NoC tiles (or assigning threads to cores in chip multiprocessors) can reduce end-to-end delay and energy consumption. While almost all previous works on mapping consider higher priority for the application's flows with higher required bandwidth, a mapping strategy, presented in this paper, is introduced that considers multicast communication flows in addition to the normal unicast flows. To this end, multicast and unicast traffic flows are first characterized in terms of some new metrics which are... 

Microbial desalination cell (MDC) is a new bio-electrochemical technique which converts chemical energy into electrical energy, and at the same time desalinates water and treats wastewater. In this study, MDC performance and water biofouling conditions were tested as an efficient pretreatment desalination process of reverse osmosis (RO). The experiments were designed in a three-chamber reactor to compare the performance of batch and continuous fed modes, using bio-cathode and synthetic wastewater in four different hydraulic retention times and 17 and 35 g/L NaCl concentrations. According to the results, maximum salt removal of about 52.3% was obtained in the continuously fed MDC at 35 g/L... 

The global shift toward solar energy has resulted in the advancement of research into the manufacture of high-performance solar cells. It is critical to accurately model and identify the parameters of solar cells. Numerous models of solar cells have been presented thus far, including the single-diode, the double-diode, and the three-diode models. Every model contains a number of unidentified parameters, and numerous approaches for determining their optimal values have been published in the literature. The purpose of this article is to propose an efficient optimization technique, dubbed the Chimp Optimization Algorithm (ChOA), for estimating the model parameters of solar networks. The... 

In this study, buckling and vibrational characteristics of a nanoshell reinforced with graphene nanoplatelets under uniform axial load are investigated. The material properties of the piece-wise graphene-reinforced composites (GPLRCs) are assumed to be graded in the thickness direction of a nanoshell and are estimated using a nanomechanical model. The effects of the small scale are analyzed based on nonlocal stress–strain gradient theory (NSGT). The governing equations and boundary conditions (BCs) are developed using Hamilton’s principle and are solved with assistance of the generalized differential quadrature method. The novelty of the current study is the consideration of GPLRC and size... 

In this research, thermal buckling and forced vibration characteristics of the imperfect composite cylindrical nanoshell reinforced with graphene nanoplatelets (GNP) in thermal environments are presented. Halpin–Tsai nanomechanical model is used to determine the material properties of each layer. The size-dependent effects of GNPRC nanoshell is analyzed using modified couple stress theory. For the first time, in the present study, porous functionally graded multilayer couple stress (FMCS) parameter which changes along the thickness is considered. The novelty of the current study is to consider the effects of porosity, GNPRC, FMCS and thermal environment on the resonance frequencies, thermal... 

This is the first research on the nonlinear frequency analysis of a multi-scale hybrid nanocomposite (MHC) disk (MHCD) resting on an elastic foundation subjected to nonlinear temperature gradient and mechanical loading is investigated. The matrix material is reinforced with carbon nanotubes (CNTs) or carbon fibers (CF) at the nano- or macroscale, respectively. We present a modified Halpin–Tsai model to predict the effective properties of the MHCD. The displacement–strain of nonlinear vibration of multi-scale laminated disk via third-order shear deformation theory (TSDT) and using Von Karman nonlinear shell theory is obtained. Hamilton’s principle is employed to establish the governing... 

Due to rapid development of manufacturing process, composite materials with porosity have attracted commercially notices in advanced engineering applications. For this regard, buckling and vibrational characteristics of a porous composite cylindrical nanoshell reinforced with GPLs is investigated in this paper. The material properties of piece-wise graphene-reinforced composites (GPLRC) are assumed to be graded in the thickness direction of a cylindrical nanoshell and are estimated using a nanomechanical model. The novelty of our work is including the effects of porosity and GPLRC on natural frequency, critical axial load and critical temperature of the GPLRC cylindrical nanoshell. The... 

This is the first research on the nonlinear frequency analysis of a multi-scale hybrid nanocomposite (MHC) disk (MHCD) resting on an elastic foundation subjected to nonlinear temperature gradient and mechanical loading is investigated. The matrix material is reinforced with carbon nanotubes (CNTs) or carbon fibers (CF) at the nano- or macroscale, respectively. We present a modified Halpin–Tsai model to predict the effective properties of the MHCD. The displacement–strain of nonlinear vibration of multi-scale laminated disk via third-order shear deformation theory (TSDT) and using Von Karman nonlinear shell theory is obtained. Hamilton’s principle is employed to establish the governing... 

This survey addresses the non-polynomial framework for bending responses of three-phase multi-scale hybrid laminated nanocomposite (MHLNC) reinforced circular/annular plates (MHLNCRCP/ MHLNCRAP) based upon the three-dimensional theory of elasticity for various sets of boundary conditions. The sandwich structure with two, three, five, and seven layers is modeled using compatibility conditions. The state-space based differential quadrature method (SS-DQM) is presented to examine the bending behavior of MHLNCRCP/ MHLNCRAP by considering various boundary conditions. Halpin–Tsai equations and fiber micromechanics are used in the hierarchy to predict the bulk material properties of the multi-scale... 

The use of randomly distributed graphene platelets as a reinforcing material in tilted curved pipes subjected to supersonic airflow has become an increasingly popular area of research due to their potential to enhance the mechanical and thermal properties of the pipes. In this study, the focus is on investigating the frequency or dynamic response of these reinforced pipes under supersonic airflow conditions. In doing so, a higher-order shear deformation theory is utilized for modeling the displacement field in the tilted pipe structure. Moreover, the classical theory of elasticity with the incorporation of the effects of thermal loading is considered in obtaining governing equations. The... 

Controlling networked dynamical systems is a complex endeavor, specifically keeping in mind the fact that in many scenarios the actors that are engaged in the dynamism behave selfishly and therefore only take into account their own individual utility, a setting that has been widely studied in the field of game theory. One way that we can control the system dynamics is through the use of control parameters that are at our disposal, but finding optimal values for these parameters is a complex and time consuming task. In this paper we use the relation between network structural properties and control parameters to create a mathematical model that uses learning methods to find optimal values... 

For the first time, in this article, stable/unstable zones of multi-directional functionally graded (MD-FG) sector disks under aerodynamic pressures are sought. Also, because of porous media, the system is modeled as a poroelastic system. The damping matrix, together with the aerodynamic stiffness matrix, is modeled upon Krumhaar's modified supersonic piston hypothesis. For more accuracy of the results, the Series-Fourier expansion of displacement fields in two-dimension is considered. To solve the partial differential equations, the singular convolution integration method with a singular convolution, as a numerical solver, is used. The precision of the outcomes is verified with those... 

The first spoken dialogue system is developed for the Persian language is introduced. This is a ticket reservation system with Persian ASR and NLU modules. The focus of the paper is on learning the dialogue management module. In this work, real on-line training data are used during the learning process. For on-line learning, the effect of the variations of discount factor (γ) on the learning speed is investigated as the second contribution of the research. The optimal values for γ were found and the variation pattern of the action-value function (Q) in the learning process was obtained. A probabilistic policy for selecting actions is used in this work for the first time instead of greedy... 

Business processes perform a significant role in increasing the success of organizational processes and functionalities. Due to the ever increasing growth in the scale and complexity of processes in line with taking advantage of combinational methods and ideas to optimize workflows and gain higher efficiency, lack of a framework considering both business process semantic and structure for business process modeling is completely sensible. Adding semantic to business process models will result in more comprehensible and automatically-executable processes. Moreover, preparing a suitable structure by making use of software architectural concepts will lead to a major decrease in misunderstanding...