Pub Date : 2023-03-31DOI: 10.15625/0866-7136/18182
Duong The Hung
An explicit expression of natural frequencies through crack parameters is derived for multiple cracked beams with simply supported boundaries using the Rayleigh quotient. The obtained expression provides not only a simple tool for calculating natural frequencies of multiple cracked beams, but also allows employing the so-called crack scanning method for detecting multiple cracks in simply supported beams from measured natural frequencies. A numerical example demonstrates that the crack scanning method, in combination with the Rayleigh quotient, enables consistent identification of cracks with 1% relative depth.
{"title":"An application of Rayleigh quotient for crack detection in simply supported beam","authors":"Duong The Hung","doi":"10.15625/0866-7136/18182","DOIUrl":"https://doi.org/10.15625/0866-7136/18182","url":null,"abstract":"An explicit expression of natural frequencies through crack parameters is derived for multiple cracked beams with simply supported boundaries using the Rayleigh quotient. The obtained expression provides not only a simple tool for calculating natural frequencies of multiple cracked beams, but also allows employing the so-called crack scanning method for detecting multiple cracks in simply supported beams from measured natural frequencies. A numerical example demonstrates that the crack scanning method, in combination with the Rayleigh quotient, enables consistent identification of cracks with 1% relative depth.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132053433","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 : 2023-03-31DOI: 10.15625/0866-7136/17305
N. D. Bich, Nguyen Hoang Tung, Le Xuan Tung
For the resulting equation of double-curved shells, which is formed by revolution of an arbitrary in-plane meridian curve and cannot be represented analytically, there exists no analytical approach to problem setting and solution. This paper presents the digitalization of the meridian curve in the polar coordinate system, which forms double number series. The double number series then can be approximated by an interpolation function so that calculations can be performed in a similar methodology for an explicit function. Digitalization enables the input parameters in the form of interpolation functions. Procedures for the proposed selection of solution forms, formation of the kinetic equation, and computation of coefficients for the kinetic equation from on the interpolation and explicit functions are presented in the paper. The final solution is obtained by using the program Mathematica 7.0 to solve the system of nonlinear differential equations. Assessment of the dynamic response of the double-curved shell, especially responses with chaotic motion, is also presented in the paper.
{"title":"Dynamic response of arbitrary double-curved shells by meridian curve digitalization","authors":"N. D. Bich, Nguyen Hoang Tung, Le Xuan Tung","doi":"10.15625/0866-7136/17305","DOIUrl":"https://doi.org/10.15625/0866-7136/17305","url":null,"abstract":"For the resulting equation of double-curved shells, which is formed by revolution of an arbitrary in-plane meridian curve and cannot be represented analytically, there exists no analytical approach to problem setting and solution. This paper presents the digitalization of the meridian curve in the polar coordinate system, which forms double number series. The double number series then can be approximated by an interpolation function so that calculations can be performed in a similar methodology for an explicit function. Digitalization enables the input parameters in the form of interpolation functions. Procedures for the proposed selection of solution forms, formation of the kinetic equation, and computation of coefficients for the kinetic equation from on the interpolation and explicit functions are presented in the paper. The final solution is obtained by using the program Mathematica 7.0 to solve the system of nonlinear differential equations. Assessment of the dynamic response of the double-curved shell, especially responses with chaotic motion, is also presented in the paper.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130038658","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 : 2023-03-20DOI: 10.15625/0866-7136/17956
Xuan-Bach Bui, Anh-Cao Nguyen, Ngoc-Duong Nguyen, T. Do, T. Nguyen
Despite the extensive use of thin-walled structures, the studies on their behaviours when exposed to extreme thermal environment are relatively scarce. Therefore, this paper aims to present the buckling analysis of thin-walled composite I-beams under thermo-mechanical loads. The thermal effects are investigated for the case of studied beams undergoing a uniform temperature rise through their thickness. The theory is based on the first-order shear deformation thin-walled beam theory with linear variation of displacements in the wall thickness. The governing equations of motion are derived from Hamilton's principle and are solved by series-type solutions with hybrid shape functions. Numerical results are presented to investigate the effects of fibre angle, material distribution, span-to-height's ratio and shear deformation on the critical buckling load and temperature rise. These results for several cases are verified with available references to demonstrate the present beam model’s accuracy.
{"title":"Buckling analysis of laminated composite thin-walled I-beam under mechanical and thermal loads","authors":"Xuan-Bach Bui, Anh-Cao Nguyen, Ngoc-Duong Nguyen, T. Do, T. Nguyen","doi":"10.15625/0866-7136/17956","DOIUrl":"https://doi.org/10.15625/0866-7136/17956","url":null,"abstract":"Despite the extensive use of thin-walled structures, the studies on their behaviours when exposed to extreme thermal environment are relatively scarce. Therefore, this paper aims to present the buckling analysis of thin-walled composite I-beams under thermo-mechanical loads. The thermal effects are investigated for the case of studied beams undergoing a uniform temperature rise through their thickness. The theory is based on the first-order shear deformation thin-walled beam theory with linear variation of displacements in the wall thickness. The governing equations of motion are derived from Hamilton's principle and are solved by series-type solutions with hybrid shape functions. Numerical results are presented to investigate the effects of fibre angle, material distribution, span-to-height's ratio and shear deformation on the critical buckling load and temperature rise. These results for several cases are verified with available references to demonstrate the present beam model’s accuracy.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127289083","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 : 2023-03-01DOI: 10.15625/0866-7136/17552
Van-Thien Tran, V. Nguyen, T. Nguyen, T. Vo
Based on fundamental equations of the elasticity theory, a unified higher-order shear deformation theory is developed for bending and free vibration analysis of functionally graded (FG) microplates with porosities. The modified strain gradient theory is employed to capture the size effects. Bi-directional series with hybrid shape functions are used to solve the problems. Several important effects including thickness-to-material length scale parameters, side-to-thickness ratio, and boundary conditions on the deflections and natural frequencies of FG porous microplates are investigated.
{"title":"Static and vibration analysis of functionally graded microplate with porosities based on higher-order shear deformation and modified strain gradient theory","authors":"Van-Thien Tran, V. Nguyen, T. Nguyen, T. Vo","doi":"10.15625/0866-7136/17552","DOIUrl":"https://doi.org/10.15625/0866-7136/17552","url":null,"abstract":"Based on fundamental equations of the elasticity theory, a unified higher-order shear deformation theory is developed for bending and free vibration analysis of functionally graded (FG) microplates with porosities. The modified strain gradient theory is employed to capture the size effects. Bi-directional series with hybrid shape functions are used to solve the problems. Several important effects including thickness-to-material length scale parameters, side-to-thickness ratio, and boundary conditions on the deflections and natural frequencies of FG porous microplates are investigated.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128870252","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 : 2023-01-02DOI: 10.15625/0866-7136/16977
N. Hoang, Vu Duc Vuong, Dinh Van Phong, Nguyen Tung Lam
This paper presents the dynamic model and singularity-free simulation of electromechanical systems including closed loop multibody systems, massless gear transmission and electric motors. The dynamic model of these systems is established in matrix form and written in a Differential-Algebraic Equations form by applying the Lagrangian equation with multipliers and substructure method. Moreover, this paper deals with two difficult issues in the simulation of closed-loop multibody systems which are to overcome smoothly the singular configurations and to stabilize the constrained equations due to accumulated errors. The singularity-free simulation is solved by using null-space of Jacobian matrix to eliminate the constraint forces – Lagrangian multipliers in equations of motion. The drift in the constraint equation during simulation is restricted by a combination of Baumgarte’s stabilization and post-adjusting technique. Some numerical experiments are carried out to the planar 3RRR parallel manipulator driven by electric motors. Simulation results confirm the effectiveness of the proposed approach in overcoming the singular configurations and in stabilization of the constraint.
{"title":"Dynamic modelling and singularity-free simulation of closed loop multibody system driven by electric motors","authors":"N. Hoang, Vu Duc Vuong, Dinh Van Phong, Nguyen Tung Lam","doi":"10.15625/0866-7136/16977","DOIUrl":"https://doi.org/10.15625/0866-7136/16977","url":null,"abstract":"This paper presents the dynamic model and singularity-free simulation of electromechanical systems including closed loop multibody systems, massless gear transmission and electric motors. The dynamic model of these systems is established in matrix form and written in a Differential-Algebraic Equations form by applying the Lagrangian equation with multipliers and substructure method. Moreover, this paper deals with two difficult issues in the simulation of closed-loop multibody systems which are to overcome smoothly the singular configurations and to stabilize the constrained equations due to accumulated errors. The singularity-free simulation is solved by using null-space of Jacobian matrix to eliminate the constraint forces – Lagrangian multipliers in equations of motion. The drift in the constraint equation during simulation is restricted by a combination of Baumgarte’s stabilization and post-adjusting technique. Some numerical experiments are carried out to the planar 3RRR parallel manipulator driven by electric motors. Simulation results confirm the effectiveness of the proposed approach in overcoming the singular configurations and in stabilization of the constraint.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128060786","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 : 2023-01-02DOI: 10.15625/0866-7136/17938
P. Dat, Le Pham Binh
Composite plates are high-tech structures used in many areas of modern engineering, like building, space travel, ships, etc. In practice, these structures are often used in their thin form, typically a reinforced composite plate subjected to dynamic loads. Therefore, when subjected to loads, the plate may be instability. The article presents the element model, finite element algorithm, and buckling analysis results of reinforced composite plates subjected to dynamic loads in order to determine the buckling domain. Furthermore, the influence of some factors such as geometric parameters, reinforcing stiffeners, and material characteristics on the buckling domain of the plate is studied in detail.
{"title":"Dynamic buckling analysis of reinforced composite plate subjected to harmonic loads","authors":"P. Dat, Le Pham Binh","doi":"10.15625/0866-7136/17938","DOIUrl":"https://doi.org/10.15625/0866-7136/17938","url":null,"abstract":"Composite plates are high-tech structures used in many areas of modern engineering, like building, space travel, ships, etc. In practice, these structures are often used in their thin form, typically a reinforced composite plate subjected to dynamic loads. Therefore, when subjected to loads, the plate may be instability. The article presents the element model, finite element algorithm, and buckling analysis results of reinforced composite plates subjected to dynamic loads in order to determine the buckling domain. Furthermore, the influence of some factors such as geometric parameters, reinforcing stiffeners, and material characteristics on the buckling domain of the plate is studied in detail.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127126090","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 : 2022-12-31DOI: 10.15625/0866-7136/17980
Pham Van Hoan, Dao Nhu Mai, K. V. Phu, L. K. Hoa
This paper deals with the nonlinear buckling and post-buckling of sandwich cylindrical panels with non-uniform porous core and functionally graded face sheets. The imperfect sandwich cylindrical panels are subjected to axial loading on elastic foundation. Based on the Donnell shell theory, with von Kármán geometrical nonlinearity, the governing equations are derived. The effects of elastic foundation, various panel geometrical characteristics, porosity parameters, and the thickness of the porous core are investigated. The effects of foundation parameters, porosity parameters, the thickness of the porous core, and material parameters are investigated.
{"title":"Nonlinear buckling and post-buckling of imperfect FG porous sandwich cylindrical panels subjected to axial loading on elastic foundation","authors":"Pham Van Hoan, Dao Nhu Mai, K. V. Phu, L. K. Hoa","doi":"10.15625/0866-7136/17980","DOIUrl":"https://doi.org/10.15625/0866-7136/17980","url":null,"abstract":"This paper deals with the nonlinear buckling and post-buckling of sandwich cylindrical panels with non-uniform porous core and functionally graded face sheets. The imperfect sandwich cylindrical panels are subjected to axial loading on elastic foundation. Based on the Donnell shell theory, with von Kármán geometrical nonlinearity, the governing equations are derived. The effects of elastic foundation, various panel geometrical characteristics, porosity parameters, and the thickness of the porous core are investigated. The effects of foundation parameters, porosity parameters, the thickness of the porous core, and material parameters are investigated.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123383130","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 : 2022-12-31DOI: 10.15625/0866-7136/17999
Kim Tran-Quoc, Lieu B. Nguyen, V. Luong, H. Nguyen-Xuan
Bioinspired structures are remarkable porous structures with great strength-to-weight ratios. Hence, they have been applied in various fields including biomedical, transportation, and aerospace materials, etc. Recent studies have shown the significant impact of the plastic 3D printed triply periodic minimal surfaces (TPMS) structure on the cement beam including increasing the peak load, reducing the deflection, and improving the ductility. In this study, a machine learning (ML) surrogate model has been conducted to predict the beam behavior under static bending load. At first, various combinations of plastic volume fractions and numbers of core layers have been adopted to reinforce the constituent beam. The finite element method (FEM) was implemented to investigate the influences of these reinforcement strategies. Next, the above data were employed to create the ML model. A three-process assessment was proposed to achieve the most suitable model for the present problem, these processes were the model hyperparameter tuning, the performance assessment, and the handling overfitting with deep learning (DL) techniques. Consequently, both beam peak loads and maximum deflections were proportional to the volume fraction. The increment in TPMS layers could lead to the enhancement in both traits but with a nonlinear relationship. Furthermore, each trait may be a ceiling value that could not be exceeded with a specific volume fraction despite any number of layers. This conclusion was indicated by the surrogate model predictions. The final model in this study could deal with noisy data from FEM and with the support of a new early stopping condition, excellent performance could be found on both train and test data. The maximum deviations of 2.5% and 3.5% for peak loads and maximum midpoint displacements, respectively, have verified the robustness of the present surrogate model.
{"title":"Machine learning for predicting mechanical behavior of concrete beams with 3D printed TPMS","authors":"Kim Tran-Quoc, Lieu B. Nguyen, V. Luong, H. Nguyen-Xuan","doi":"10.15625/0866-7136/17999","DOIUrl":"https://doi.org/10.15625/0866-7136/17999","url":null,"abstract":"Bioinspired structures are remarkable porous structures with great strength-to-weight ratios. Hence, they have been applied in various fields including biomedical, transportation, and aerospace materials, etc. Recent studies have shown the significant impact of the plastic 3D printed triply periodic minimal surfaces (TPMS) structure on the cement beam including increasing the peak load, reducing the deflection, and improving the ductility. In this study, a machine learning (ML) surrogate model has been conducted to predict the beam behavior under static bending load. At first, various combinations of plastic volume fractions and numbers of core layers have been adopted to reinforce the constituent beam. The finite element method (FEM) was implemented to investigate the influences of these reinforcement strategies. Next, the above data were employed to create the ML model. A three-process assessment was proposed to achieve the most suitable model for the present problem, these processes were the model hyperparameter tuning, the performance assessment, and the handling overfitting with deep learning (DL) techniques. Consequently, both beam peak loads and maximum deflections were proportional to the volume fraction. The increment in TPMS layers could lead to the enhancement in both traits but with a nonlinear relationship. Furthermore, each trait may be a ceiling value that could not be exceeded with a specific volume fraction despite any number of layers. This conclusion was indicated by the surrogate model predictions. The final model in this study could deal with noisy data from FEM and with the support of a new early stopping condition, excellent performance could be found on both train and test data. The maximum deviations of 2.5% and 3.5% for peak loads and maximum midpoint displacements, respectively, have verified the robustness of the present surrogate model. \u0000 \u0000 ","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127119689","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 : 2022-12-31DOI: 10.15625/0866-7136/17979
B. Huy, L. Thang, D. B. Tri, Nguyen Ngoc Diep, Nguyen Quoc Hung
This study focuses on the development of magnetorheological fluid (MRF) based clutch systems for speed control of a rotary load. A new configuration for speed control of a rotary shaft using a magnetorheological clutch (MRC) with stationary winding housing and its mathematical model are proposed based on the Bingham plastic model of MRF. Multi-objective design optimization for MRCs simultaneously considering power consumption, transmitting torque, and rotating mass is then studied based on the derived mathematical model and electromagnetic finite element analysis (FEA) of the MRC. Subsequently, an optimal configuration of the proposed MRC is manufactured and experimentally investigated.
{"title":"Multi-objective optimization of magnetorheological clutch with stationary housing","authors":"B. Huy, L. Thang, D. B. Tri, Nguyen Ngoc Diep, Nguyen Quoc Hung","doi":"10.15625/0866-7136/17979","DOIUrl":"https://doi.org/10.15625/0866-7136/17979","url":null,"abstract":"This study focuses on the development of magnetorheological fluid (MRF) based clutch systems for speed control of a rotary load. A new configuration for speed control of a rotary shaft using a magnetorheological clutch (MRC) with stationary winding housing and its mathematical model are proposed based on the Bingham plastic model of MRF. Multi-objective design optimization for MRCs simultaneously considering power consumption, transmitting torque, and rotating mass is then studied based on the derived mathematical model and electromagnetic finite element analysis (FEA) of the MRC. Subsequently, an optimal configuration of the proposed MRC is manufactured and experimentally investigated.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125976954","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 : 2022-12-31DOI: 10.15625/0866-7136/17985
Phuc L. H. Ho, C. Le, P. H. Nguyen, Chanh T. Ngo
This paper presents a novel formulation for the computational homogenization analysis of materials at the limit state. The polynomial interpolations are employed to impose the periodic boundary conditions for the fluctuating term of the displacement field when using arbitrary finite element meshes. Second-order cone programming provides an efficient solution to solve the resulting optimization problems, and accurate load multipliers can be obtained with the minimum computational cost. Several asymmetrical material models are investigated to perform the efficiency of the proposed method. The collapse mechanisms of the representative volume elements are also presented.
{"title":"Limit state analysis of asymmetrical microstructures based on yield design computational homogenization approach","authors":"Phuc L. H. Ho, C. Le, P. H. Nguyen, Chanh T. Ngo","doi":"10.15625/0866-7136/17985","DOIUrl":"https://doi.org/10.15625/0866-7136/17985","url":null,"abstract":"This paper presents a novel formulation for the computational homogenization analysis of materials at the limit state. The polynomial interpolations are employed to impose the periodic boundary conditions for the fluctuating term of the displacement field when using arbitrary finite element meshes. Second-order cone programming provides an efficient solution to solve the resulting optimization problems, and accurate load multipliers can be obtained with the minimum computational cost. Several asymmetrical material models are investigated to perform the efficiency of the proposed method. The collapse mechanisms of the representative volume elements are also presented.","PeriodicalId":239329,"journal":{"name":"Vietnam Journal of Mechanics","volume":"18 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123512166","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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