Pub Date : 2022-09-16DOI: 10.37394/232011.2022.17.17
E. Prozorova
The article is devoted to the study of some violations of the known laws of mathematics and classical mechanics in continuum mechanics and kinetics. The most common is open non-stationary systems. From the equations formulated earlier and some experiments, a connection traced between the gradients of physical quantities and the angular momentum (force). The use of Hamilton's formalism and the dependence of force only on the distance between particles limits the study. In the collision integral, for example, for a rarefied gas, the Lennard-Jones potential, which not related to the type under consideration, is often used. Hamilton's formalism traces the behavior of closed systems. The general form of boundary conditions and forces changes the theory proposed in the works of N.N. Bogolyubov. The results of the reformulation discussed. Even in the classical theory, after taking into account the moments, we come to the absence of symmetric stress tensor in Boltzmann theory. The symmetric tensor obtains after assumption of small influence from absence of symmetry at the condition of the forces balance. No symmetric tensor leads to the existence of two solutions. New examples of solving problems on hydromechanics, elasticity theory and kinetic theory are given. A correspondence between the terms of the Liouville equation with more general and traditional forces established for continues mechanics. Previously considered boundary layer problems, jet problems and the simplest problems of elasticity theory. The paper proposes a method for finding the second solution for no symmetric problems, if the solution of the symmetric problem we know. The mathematical inaccuracies of the theory of continuum mechanics and kinetics discussed.
{"title":"Some Consequences of Mathematical Inaccuracies in Mechanics","authors":"E. Prozorova","doi":"10.37394/232011.2022.17.17","DOIUrl":"https://doi.org/10.37394/232011.2022.17.17","url":null,"abstract":"The article is devoted to the study of some violations of the known laws of mathematics and classical mechanics in continuum mechanics and kinetics. The most common is open non-stationary systems. From the equations formulated earlier and some experiments, a connection traced between the gradients of physical quantities and the angular momentum (force). The use of Hamilton's formalism and the dependence of force only on the distance between particles limits the study. In the collision integral, for example, for a rarefied gas, the Lennard-Jones potential, which not related to the type under consideration, is often used. Hamilton's formalism traces the behavior of closed systems. The general form of boundary conditions and forces changes the theory proposed in the works of N.N. Bogolyubov. The results of the reformulation discussed. Even in the classical theory, after taking into account the moments, we come to the absence of symmetric stress tensor in Boltzmann theory. The symmetric tensor obtains after assumption of small influence from absence of symmetry at the condition of the forces balance. No symmetric tensor leads to the existence of two solutions. New examples of solving problems on hydromechanics, elasticity theory and kinetic theory are given. A correspondence between the terms of the Liouville equation with more general and traditional forces established for continues mechanics. Previously considered boundary layer problems, jet problems and the simplest problems of elasticity theory. The paper proposes a method for finding the second solution for no symmetric problems, if the solution of the symmetric problem we know. The mathematical inaccuracies of the theory of continuum mechanics and kinetics discussed.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42527775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-13DOI: 10.37394/232011.2022.17.15
F. Gallerano, Benedetta Iele, F. Palleschi, G. Cannata
The three-dimensional motion equations are used to simulate the wave and velocity fields. These equations are written in integral contravariant form on a time-dependent curvilinear coordinate system. In this paper a new ?−? turbulence model in contravariant form is proposed for three-dimensional simulation of breaking waves. In this model the mixing length is defined as a function of the first and second spatial derivatives of the maximum water surface elevation.
{"title":"Breaking Wave Simulations by a New k−l Turbulence Model","authors":"F. Gallerano, Benedetta Iele, F. Palleschi, G. Cannata","doi":"10.37394/232011.2022.17.15","DOIUrl":"https://doi.org/10.37394/232011.2022.17.15","url":null,"abstract":"The three-dimensional motion equations are used to simulate the wave and velocity fields. These equations are written in integral contravariant form on a time-dependent curvilinear coordinate system. In this paper a new ?−? turbulence model in contravariant form is proposed for three-dimensional simulation of breaking waves. In this model the mixing length is defined as a function of the first and second spatial derivatives of the maximum water surface elevation.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48431403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-13DOI: 10.37394/232011.2022.17.16
A. Muc
In the present paper buckling problems of constructions with a single delamination are conducted. Structures are made of laminates and functionally graded materials (FGM). The first part of the work is devoted to the formulation of contact problems with the aid of various functional inequalities. Then computational models are discussed. Finally two particular problems dealing with buckling of spherical shells and compressed rectangular plates. The results demonstrate that the unsymmetric configurations of FGM structures leads to the reduction of buckling loads for structures with delamination.
{"title":"Computational and Variational Formulations of Unilateral Problems for Structures Made of Composite Materials (Laminates, Functionally Graded Materials)","authors":"A. Muc","doi":"10.37394/232011.2022.17.16","DOIUrl":"https://doi.org/10.37394/232011.2022.17.16","url":null,"abstract":"In the present paper buckling problems of constructions with a single delamination are conducted. Structures are made of laminates and functionally graded materials (FGM). The first part of the work is devoted to the formulation of contact problems with the aid of various functional inequalities. Then computational models are discussed. Finally two particular problems dealing with buckling of spherical shells and compressed rectangular plates. The results demonstrate that the unsymmetric configurations of FGM structures leads to the reduction of buckling loads for structures with delamination.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49069436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-28DOI: 10.37394/232011.2022.17.14
I. Burova
Integro-differential equations are encountered when solving various problems of mechanics. Although Integro-Differential equations are encountered frequently in mathematical analysis of mechanical problems, very few of these equations will ever give us analytic solutions in a closed form. So that construction of numerical methods is the only way to find the approximate solution. This paper discusses the calculation schemes for solving integro-differential equations using local polynomial spline approximations of the Lagrangian type of the fourth and fifth orders of approximation. The features of solving integro-differential equations with the first derivative and the Fredholm and Volterra integrals of the second kind are discussed. Using the proposed spline approximations, formulas for numerical differentiation are obtained. These formulas are used to approximate the first derivative of a function. The numerical experiments are presented.
{"title":"Local Interpolation Splines and Solution of Integro-Differential Equations of Mechanic’s Problems","authors":"I. Burova","doi":"10.37394/232011.2022.17.14","DOIUrl":"https://doi.org/10.37394/232011.2022.17.14","url":null,"abstract":"Integro-differential equations are encountered when solving various problems of mechanics. Although Integro-Differential equations are encountered frequently in mathematical analysis of mechanical problems, very few of these equations will ever give us analytic solutions in a closed form. So that construction of numerical methods is the only way to find the approximate solution. This paper discusses the calculation schemes for solving integro-differential equations using local polynomial spline approximations of the Lagrangian type of the fourth and fifth orders of approximation. The features of solving integro-differential equations with the first derivative and the Fredholm and Volterra integrals of the second kind are discussed. Using the proposed spline approximations, formulas for numerical differentiation are obtained. These formulas are used to approximate the first derivative of a function. The numerical experiments are presented.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41713204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-19DOI: 10.37394/232011.2022.17.13
Ali J. Khalaf, Abeer S. Alfayhan, Mohammed A. AL-Shareafi
Thin films from CuFe2O3: Cu were prepared with different weights and then the membranes were prepared using a spin coating method with the rotation speed are (2000,3000,4000,5000) rpm respectively and the rotation time is 7s.. The films were examined as gas sensor against NH3gas at operating temperatures (200) °C, also sensitivity of films for gases increases with decreases temperature. The variation of the operating temperature of the films have led to a significant change in the sensitivity of the sensor. The gas sensor at the operating temperature of an to increasing in recovery response time and decreasing in response.
{"title":"Synthesis Gas Sensor from CuFe2O3: Cu Films by Spin Coating","authors":"Ali J. Khalaf, Abeer S. Alfayhan, Mohammed A. AL-Shareafi","doi":"10.37394/232011.2022.17.13","DOIUrl":"https://doi.org/10.37394/232011.2022.17.13","url":null,"abstract":"Thin films from CuFe2O3: Cu were prepared with different weights and then the membranes were prepared using a spin coating method with the rotation speed are (2000,3000,4000,5000) rpm respectively and the rotation time is 7s.. The films were examined as gas sensor against NH3gas at operating temperatures (200) °C, also sensitivity of films for gases increases with decreases temperature. The variation of the operating temperature of the films have led to a significant change in the sensitivity of the sensor. The gas sensor at the operating temperature of an to increasing in recovery response time and decreasing in response.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48932073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-19DOI: 10.37394/232011.2022.17.12
M. Abo-Elnor
Bascule bridges are widely used nowadays to overcome the obstruction of ships passage as crossing waterways and in some roadways to overcome transport vehicle height limitation. A Bascule bridge is a movable bridge with a counterweight that continuously balances a span, or "leaf", throughout its upward swing to provide clearance for boat or ship traffic. It may be single or double leafed. Balance Beam Bascule Bridge is one of the famous bascule bridge architecture in which bridge span counter balance weight is attached to a balance beam in the movable bridge operating mechanism. Although hydraulic cylinders is a particularly common solution to power majority of modern bascule bridges, it is very important to understand the kinematics and motion of the bridge leave for optimum operation of the bridge with prober counter balance selection. In this study a review of two operating hydraulic actuators arrangements; push arrangement and pull arrangement is carried out based on both design aspects and safety consideration. 3D model of the study mechanisms are constructed and a kinematics of bridge leaf (span) opening mechanisms are developed for early stage design configuration of bridge mechanism. kinematic analyses of bridge mechanism operation in both push and pull arrangements based on rigid body consideration is performed and Numerical analysis using finite element method is carried out in which stress distribution over tie rods is obtained. Some failure scenarios are introduced. Results show that tension forces acting on tie rods in pull arrangement is lower than that in push arrangement, work done by hydraulic cylinders (Actuators) in both arrangement is nearly identical and pull arrangement is much better than push arrangement from safety point of view.
{"title":"Analysis of Different Bascule Bridge Architectures","authors":"M. Abo-Elnor","doi":"10.37394/232011.2022.17.12","DOIUrl":"https://doi.org/10.37394/232011.2022.17.12","url":null,"abstract":"Bascule bridges are widely used nowadays to overcome the obstruction of ships passage as crossing waterways and in some roadways to overcome transport vehicle height limitation. A Bascule bridge is a movable bridge with a counterweight that continuously balances a span, or \"leaf\", throughout its upward swing to provide clearance for boat or ship traffic. It may be single or double leafed. Balance Beam Bascule Bridge is one of the famous bascule bridge architecture in which bridge span counter balance weight is attached to a balance beam in the movable bridge operating mechanism. Although hydraulic cylinders is a particularly common solution to power majority of modern bascule bridges, it is very important to understand the kinematics and motion of the bridge leave for optimum operation of the bridge with prober counter balance selection. In this study a review of two operating hydraulic actuators arrangements; push arrangement and pull arrangement is carried out based on both design aspects and safety consideration. 3D model of the study mechanisms are constructed and a kinematics of bridge leaf (span) opening mechanisms are developed for early stage design configuration of bridge mechanism. kinematic analyses of bridge mechanism operation in both push and pull arrangements based on rigid body consideration is performed and Numerical analysis using finite element method is carried out in which stress distribution over tie rods is obtained. Some failure scenarios are introduced. Results show that tension forces acting on tie rods in pull arrangement is lower than that in push arrangement, work done by hydraulic cylinders (Actuators) in both arrangement is nearly identical and pull arrangement is much better than push arrangement from safety point of view.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42128338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-06DOI: 10.37394/232011.2022.17.11
Pierangelo Malfi, A. Nicolella, M. Spirto, C. Cosenza, V. Niola, S. Savino
The employment of mobile robots, remotely or autonomously controlled for field operations, is an emerging topic. The development of suitable simulation models can aid the design and testing of such mobile robots. Here a small commercial prototype of a Rocker-Bogie Rover has been employed in experimental tests compared to simulations on a multibody model. In particular, the tests have dealt with the acquisition and processing of accelerometer signals both on experimental prototype and in simulation environment. The paper proposes a real time signal processing approach that could aid the motion planning and rover navigation control.
{"title":"Motion Sensing Study on a Mobile Robot Through Simulation Model and Experimental Tests","authors":"Pierangelo Malfi, A. Nicolella, M. Spirto, C. Cosenza, V. Niola, S. Savino","doi":"10.37394/232011.2022.17.11","DOIUrl":"https://doi.org/10.37394/232011.2022.17.11","url":null,"abstract":"The employment of mobile robots, remotely or autonomously controlled for field operations, is an emerging topic. The development of suitable simulation models can aid the design and testing of such mobile robots. Here a small commercial prototype of a Rocker-Bogie Rover has been employed in experimental tests compared to simulations on a multibody model. In particular, the tests have dealt with the acquisition and processing of accelerometer signals both on experimental prototype and in simulation environment. The paper proposes a real time signal processing approach that could aid the motion planning and rover navigation control.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43363376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-07-04DOI: 10.37394/232011.2022.17.10
P. Aronov, Mikhail Galanin, Alexander Rodin
An algorithm for solving axisymmetric contact problems of thermoelasticity taking into account creep processes is considered. To account for the contact interaction of bodies, the mortar method was used, and the modified Jacobi method was used to solve the resulting system of linear equations. For the numerical solution of the problem simulating the creep process, time discretization based on the implicit Euler method was applied, and the Newton method was used to linearize the resulting system of equations. An algorithm with automatic step selection based on obtaining an estimate of the local error of the method is proposed. The results of applying the proposed algorithm to a demonstration problem simulating thermomechanical processes in a section of a fuel element comprising from 1 to 100 fuel pellets are presented.
{"title":"Mathematical Modeling of the Contact Interaction of the Fuel Element Section, Including up to 100 Pellets, Taking into Account Creep","authors":"P. Aronov, Mikhail Galanin, Alexander Rodin","doi":"10.37394/232011.2022.17.10","DOIUrl":"https://doi.org/10.37394/232011.2022.17.10","url":null,"abstract":"An algorithm for solving axisymmetric contact problems of thermoelasticity taking into account creep processes is considered. To account for the contact interaction of bodies, the mortar method was used, and the modified Jacobi method was used to solve the resulting system of linear equations. For the numerical solution of the problem simulating the creep process, time discretization based on the implicit Euler method was applied, and the Newton method was used to linearize the resulting system of equations. An algorithm with automatic step selection based on obtaining an estimate of the local error of the method is proposed. The results of applying the proposed algorithm to a demonstration problem simulating thermomechanical processes in a section of a fuel element comprising from 1 to 100 fuel pellets are presented.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49245277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-06-30DOI: 10.37394/232011.2022.17.9
O. Sierikova, E. Strelnikova, K. Degtyarev
The liquid hydrocarbon storage tanks are the objects of environmental danger. It is necessary to perform additional calculations and develop appropriate design solutions to minimize the risks of their accidents in the event of the earthquake or explosions. The degree of damage to the environmentally hazardous object during the earthquake depends not only on the seismic effects level, but also on the quality of seismic design and construction. The possibility of exposure to smaller but more frequent and prolonged seismic loads caused by technogenic and natural factors has not been sufficiently taken into account in tanks designing for the environmentally hazardous liquids storage. The composite materials using with nanoinclusions in tanks for storage liquid hydrocarbons, allows to increase the reliability of tanks under seismic loads and extend their service life under the influence of natural and technogenic influences of various origin. The results of the calculations have been shown that the use of composite materials with nanoinclusions in the steel spheres form is the best option for environmentally friendly operation of tanks under seismic loads.
{"title":"Seismic Loads Influence Treatment on the Liquid Hydrocarbon Storage Tanks Made of Nanocomposite Materials","authors":"O. Sierikova, E. Strelnikova, K. Degtyarev","doi":"10.37394/232011.2022.17.9","DOIUrl":"https://doi.org/10.37394/232011.2022.17.9","url":null,"abstract":"The liquid hydrocarbon storage tanks are the objects of environmental danger. It is necessary to perform additional calculations and develop appropriate design solutions to minimize the risks of their accidents in the event of the earthquake or explosions. The degree of damage to the environmentally hazardous object during the earthquake depends not only on the seismic effects level, but also on the quality of seismic design and construction. The possibility of exposure to smaller but more frequent and prolonged seismic loads caused by technogenic and natural factors has not been sufficiently taken into account in tanks designing for the environmentally hazardous liquids storage. The composite materials using with nanoinclusions in tanks for storage liquid hydrocarbons, allows to increase the reliability of tanks under seismic loads and extend their service life under the influence of natural and technogenic influences of various origin. The results of the calculations have been shown that the use of composite materials with nanoinclusions in the steel spheres form is the best option for environmentally friendly operation of tanks under seismic loads.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49641086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-06DOI: 10.37394/232011.2022.17.8
A. M. A. Al-kifaie, Narimann Neamah Hussein, Taghreed N. Jamil, Alaa A. Akon, A. Abojassim
ZnO nanoparticles have been synthesized by the Hydrothermal technique of [Zn(CH3COO)2 2H2O] solution by ethanol within NaOH. The samples have been characterized by an X-ray diffraction study. Field emission Scanning electron microscopy reveals the nanostructure of the particles produced. their crystal size ranges in the range of nm (74-94 nm) and changes to(53-59 nm) under change of the time preparation.
{"title":"Synthesis and Characterization of Nanoparticle Semiconductor Materials (ZnO) by Hydrothermal Technique","authors":"A. M. A. Al-kifaie, Narimann Neamah Hussein, Taghreed N. Jamil, Alaa A. Akon, A. Abojassim","doi":"10.37394/232011.2022.17.8","DOIUrl":"https://doi.org/10.37394/232011.2022.17.8","url":null,"abstract":"ZnO nanoparticles have been synthesized by the Hydrothermal technique of [Zn(CH3COO)2 2H2O] solution by ethanol within NaOH. The samples have been characterized by an X-ray diffraction study. Field emission Scanning electron microscopy reveals the nanostructure of the particles produced. their crystal size ranges in the range of nm (74-94 nm) and changes to(53-59 nm) under change of the time preparation.","PeriodicalId":53603,"journal":{"name":"WSEAS Transactions on Applied and Theoretical Mechanics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45940099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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