D. Karaivanov, Serik Bekzhanov, Bakhitbek Saktaganov
This article considers the Wolfrom planetary gear train, its most used variants and areas of application. It is emphasized that the train is a compound one, and not a simple one (single-carrier). It is demonstrated how a kinematic and power (efficiency) analysis of the gear train under consideration may be performed using the lever analogy and the torque method based on it. Equations for efficiency determination useful in the optimization procedures of Wolfrom planetary gear train have been developed, and propositions for its application have been given.
{"title":"Torque method investigation of wolfrom gear trains","authors":"D. Karaivanov, Serik Bekzhanov, Bakhitbek Saktaganov","doi":"10.30765/er.2099","DOIUrl":"https://doi.org/10.30765/er.2099","url":null,"abstract":"This article considers the Wolfrom planetary gear train, its most used variants and areas of application. It is emphasized that the train is a compound one, and not a simple one (single-carrier). It is demonstrated how a kinematic and power (efficiency) analysis of the gear train under consideration may be performed using the lever analogy and the torque method based on it. Equations for efficiency determination useful in the optimization procedures of Wolfrom planetary gear train have been developed, and propositions for its application have been given.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69598946","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}
The paper presents a finite element formulation for analysis of 3D framed structures with thin-walled laminated composite cross-sections, using a co-rotational approach. The formulation considers the effects of large displacements on the response of space frames subjected to conservative and static external loads. Classical lamination theory for thin fiber-reinforced laminates has been employed. Stability analysis is performed in load deflection manner using co-rotational formulation. The shear strain of the middle surface is assumed to be zero, and the cross-section is not distorted in its own plane. In order to illustrate the application of the proposed formulation, several numerical examples are presented.
{"title":"Large displacement analysis of laminated beam-type structures","authors":"Igor Pešić, G. Turkalj","doi":"10.30765/er.2184","DOIUrl":"https://doi.org/10.30765/er.2184","url":null,"abstract":"The paper presents a finite element formulation for analysis of 3D framed structures with thin-walled laminated composite cross-sections, using a co-rotational approach. The formulation considers the effects of large displacements on the response of space frames subjected to conservative and static external loads. Classical lamination theory for thin fiber-reinforced laminates has been employed. Stability analysis is performed in load deflection manner using co-rotational formulation. The shear strain of the middle surface is assumed to be zero, and the cross-section is not distorted in its own plane. In order to illustrate the application of the proposed formulation, several numerical examples are presented.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69599250","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}
Daia Eddine Oussama Mohamed Cherif, Ali Chebabhi, Abdelhalim Kessal, Mohammed Karim Fellah, Mohamed-Fouad Benkhoris
The energy provided by the PV system is strongly influenced by climatic conditions such as solar radiation and cell temperature. A suitable DC /DC converter and a robust control strategy combined with the maximum power point tracking (MPPT) algorithm are required to harness the maximum power of the panel. This paper proposes a super-twisting integral sliding mode control (ST-ISMC) for four legs interleaved boost converter (FLIBC) as an interface to the MPPT algorithm for a 60 KW PV system. The FLIBC has been used to overcome the drawbacks of the conventional boost converter (CBC). The ST-ISMC is proposed to maintain the PV voltage track the reference provided by the MPPT algorithm and ensure the equal sharing of input current between legs. The controller gains of the proposed ST-ISMC have been calculated using the grey wolf optimization algorithm for better performance. The simulation results prove the excellent performance of the proposed controller over the conventional controller.
{"title":"GWO-super-twisting integral sliding mode control of 60 KW PV system based on interleaved boost converter","authors":"Daia Eddine Oussama Mohamed Cherif, Ali Chebabhi, Abdelhalim Kessal, Mohammed Karim Fellah, Mohamed-Fouad Benkhoris","doi":"10.30765/er.2167","DOIUrl":"https://doi.org/10.30765/er.2167","url":null,"abstract":"The energy provided by the PV system is strongly influenced by climatic conditions such as solar radiation and cell temperature. A suitable DC /DC converter and a robust control strategy combined with the maximum power point tracking (MPPT) algorithm are required to harness the maximum power of the panel. This paper proposes a super-twisting integral sliding mode control (ST-ISMC) for four legs interleaved boost converter (FLIBC) as an interface to the MPPT algorithm for a 60 KW PV system. The FLIBC has been used to overcome the drawbacks of the conventional boost converter (CBC). The ST-ISMC is proposed to maintain the PV voltage track the reference provided by the MPPT algorithm and ensure the equal sharing of input current between legs. The controller gains of the proposed ST-ISMC have been calculated using the grey wolf optimization algorithm for better performance. The simulation results prove the excellent performance of the proposed controller over the conventional controller.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135101983","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}
Existence of data allows use of solution methods for differential equations that would otherwise be inapplicable. The solution process for this is formalized by using derivation matrices that reduce the time necessary for derivation and solving of differential equations. Derivation matrices are formulated by applying numerical methods in matrix notation, like finite difference schemes. In this work, a novel formulation is developed based on Lagrange polynomials with special care taken at boundary points in order to persevere a uniform precision. The main advantage of the approach is straightforward formulation, clear engineering insight into the process and (almost) arbitrary precision through choice of the interpolation order. The result of this procedure is the derivation matrix of the dimension [n×n], where 'n' is the number of data points. The resulting matrix is singular (of rank 'n-1') until boundary/initial conditions are introduced. However, that does not prevent the user to successfully differentiate its unknown function represented with the recorded data points. Derivation matrix approach is easily applicable to a wide range of engineering problems. This methodology could be extended to dynamic systems with multiple degrees of freedom and adapted when velocities or accelerations are recorded instead of displacements.
{"title":"Derivation matrix in mechanics – data approach","authors":"I. Kožar, M. Plovanić, T. Sulovsky","doi":"10.30765/er.1892","DOIUrl":"https://doi.org/10.30765/er.1892","url":null,"abstract":"Existence of data allows use of solution methods for differential equations that would otherwise be inapplicable. The solution process for this is formalized by using derivation matrices that reduce the time necessary for derivation and solving of differential equations. Derivation matrices are formulated by applying numerical methods in matrix notation, like finite difference schemes. In this work, a novel formulation is developed based on Lagrange polynomials with special care taken at boundary points in order to persevere a uniform precision. The main advantage of the approach is straightforward formulation, clear engineering insight into the process and (almost) arbitrary precision through choice of the interpolation order. The result of this procedure is the derivation matrix of the dimension [n×n], where 'n' is the number of data points. The resulting matrix is singular (of rank 'n-1') until boundary/initial conditions are introduced. However, that does not prevent the user to successfully differentiate its unknown function represented with the recorded data points. Derivation matrix approach is easily applicable to a wide range of engineering problems. This methodology could be extended to dynamic systems with multiple degrees of freedom and adapted when velocities or accelerations are recorded instead of displacements.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69598267","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}
Janhavi Saklecha, S. Pachpore, Omkar Kulkarni, G. Kakandikar
This review paper provides a comprehensive analysis of the various factors affecting micro-forming and the parameters involved in manufacturing micro-parts. To ensure minimal wear and tear and error-free products, it is important to optimize both the process parameters and framework. The paper aims to highlight the importance of metal micro-forming technology in designing and manufacturing highly precise micro metallic devices, biodegradable implants, micro-pumps, and gears. Through this review paper, readers can gain a better understanding of metal micro-forming, the variables that influence micro-forming and deep drawing, and the process parameters that affect micro-forming and deep drawing technology. Optimizing the process parameters is crucial for the success of micro-forming and can lead to improved product quality, increased production efficiency, cost reduction, process robustness, and improved material properties. The paper specifically discusses the significance of parameters such as blank holder force and size effects on variables that play an important role in optimizing the metal micro-forming process.
{"title":"Comparative analysis of parameters affecting micro-forming process","authors":"Janhavi Saklecha, S. Pachpore, Omkar Kulkarni, G. Kakandikar","doi":"10.30765/er.2163","DOIUrl":"https://doi.org/10.30765/er.2163","url":null,"abstract":"This review paper provides a comprehensive analysis of the various factors affecting micro-forming and the parameters involved in manufacturing micro-parts. To ensure minimal wear and tear and error-free products, it is important to optimize both the process parameters and framework. The paper aims to highlight the importance of metal micro-forming technology in designing and manufacturing highly precise micro metallic devices, biodegradable implants, micro-pumps, and gears. Through this review paper, readers can gain a better understanding of metal micro-forming, the variables that influence micro-forming and deep drawing, and the process parameters that affect micro-forming and deep drawing technology. Optimizing the process parameters is crucial for the success of micro-forming and can lead to improved product quality, increased production efficiency, cost reduction, process robustness, and improved material properties. The paper specifically discusses the significance of parameters such as blank holder force and size effects on variables that play an important role in optimizing the metal micro-forming process.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69599197","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}
This paper investigates the transient behavior of a novel design of an industrial mixer incorporating additional work head movement. In contrast to conventional models, this mixer consists of an elastic torsion bar with its longitudinal axis oriented orthogonally to the main drive shaft axis. Using the elastic torsion bar to hang the workhead adds an additional degree of freedom, greatly improving the mixing of fluids or powders. The motion of the electro-mechanical device was simulated using a system of nonlinear differential equations that consider the dynamic characteristics of the driving electric motor, as derived from the theorem for the rate of change of angular momentum. A numerical analysis was carried out to study the transient processes in the system under different working conditions. Finally, a constrained multiobjective optimization was performed to identify the optimal design variable values that minimize the force and power characteristics of the mixer.
{"title":"Transient motion of an industrial mixer with elastically suspended work head","authors":"Venelin Jivkov, Rosen Mitrev","doi":"10.30765/er.2301","DOIUrl":"https://doi.org/10.30765/er.2301","url":null,"abstract":"This paper investigates the transient behavior of a novel design of an industrial mixer incorporating additional work head movement. In contrast to conventional models, this mixer consists of an elastic torsion bar with its longitudinal axis oriented orthogonally to the main drive shaft axis. Using the elastic torsion bar to hang the workhead adds an additional degree of freedom, greatly improving the mixing of fluids or powders. The motion of the electro-mechanical device was simulated using a system of nonlinear differential equations that consider the dynamic characteristics of the driving electric motor, as derived from the theorem for the rate of change of angular momentum. A numerical analysis was carried out to study the transient processes in the system under different working conditions. Finally, a constrained multiobjective optimization was performed to identify the optimal design variable values that minimize the force and power characteristics of the mixer.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135446566","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}
O. Benaouda, B. Babes, Mohamed Bouchakour, Azzedine Bendiabdellah
This study aims to propose a new diagnosis technique based on the Park’s vector and the polar coordinates of electric currents for the detection and location of open-circuit faults (OC) at the level of two rectifiers connected to the grid network to feed the Gas Metal Arc Welding process (GMAW). This diagnosis technique allows the early location of faulty switches (Thyristors) to overcome the negative effect of faulty rectifiers on welding current, welding voltage, and droplet diameter. For that, the reconfigurable rectifiers have been integrated to accomplish the welding process. The proposed diagnosis technique is applied to reconfigurable rectifiers connected to the GMAW system through numerical simulations using MATLAB/Simulink and real-time processor-in-the-loop (PIL) implementation via DSpace ds 1103 card. The simulation and PIL experimental results show similar trends and great success of the diagnosis technique and the two rectifiers reconfiguration for overcoming the open circuit faults and obtaining high welding quality while maintaining the work-piece and avoiding the distortions caused by the faulty rectifiers, which affecting the grid network and on the GMAW system at the same time.
{"title":"Contribution of the two rectifiers reconfiguration to fault tolerance connected to the grid network to feed the GMAW through processor-in-the-loop","authors":"O. Benaouda, B. Babes, Mohamed Bouchakour, Azzedine Bendiabdellah","doi":"10.30765/er.1884","DOIUrl":"https://doi.org/10.30765/er.1884","url":null,"abstract":"This study aims to propose a new diagnosis technique based on the Park’s vector and the polar coordinates of electric currents for the detection and location of open-circuit faults (OC) at the level of two rectifiers connected to the grid network to feed the Gas Metal Arc Welding process (GMAW). This diagnosis technique allows the early location of faulty switches (Thyristors) to overcome the negative effect of faulty rectifiers on welding current, welding voltage, and droplet diameter. For that, the reconfigurable rectifiers have been integrated to accomplish the welding process. The proposed diagnosis technique is applied to reconfigurable rectifiers connected to the GMAW system through numerical simulations using MATLAB/Simulink and real-time processor-in-the-loop (PIL) implementation via DSpace ds 1103 card. The simulation and PIL experimental results show similar trends and great success of the diagnosis technique and the two rectifiers reconfiguration for overcoming the open circuit faults and obtaining high welding quality while maintaining the work-piece and avoiding the distortions caused by the faulty rectifiers, which affecting the grid network and on the GMAW system at the same time.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69598534","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}
The objective of the present work is the modelling of parameters influencing the temperature during friction stir lap welding. The area of physical understanding is the influence of the tool pin geometry and material on the temperature field, microstructural refinement, resulting material flow, and the influence of flow variations on the subsequent mechanical properties of FSW butt lap joints in aluminium 3003 Alloy. The results obtained allowed us to propose a mathematical model to study the interactions between different factors. Thus, it was shown that the most influential parameters are respectively the rotational speed and weld speed.
{"title":"Prediction of the temperature recorded in lap joint at during the friction stir welding","authors":"Abdelatif Mimmi, M. Merzoug, A. Ghazi","doi":"10.30765/er.2012","DOIUrl":"https://doi.org/10.30765/er.2012","url":null,"abstract":"The objective of the present work is the modelling of parameters influencing the temperature during friction stir lap welding. The area of physical understanding is the influence of the tool pin geometry and material on the temperature field, microstructural refinement, resulting material flow, and the influence of flow variations on the subsequent mechanical properties of FSW butt lap joints in aluminium 3003 Alloy. The results obtained allowed us to propose a mathematical model to study the interactions between different factors. Thus, it was shown that the most influential parameters are respectively the rotational speed and weld speed.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69599148","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}
Aleksandar Tomović, Milanko Damjanović, Radoslav Tomović, Janko Jovanović
The application of magnetic bearings has become more frequent during the last 20 years and represents a significant aspect of improvements in the construction of machines with rotary motion. With the advancement of technology, the number of applications in which magnetic bearings have found their application is increasing. In this paper, it is shown how the effect of magnetic forces can annul the negative influence of unbalance, which suddenly appeared in a rotor supported in active magnetic bearings. Such cases may occur in operation due to breakage and rotor parts falling off (e.g., fan blades), which will lead to a sudden change in the mass balance of the rotor system and dislocation of the centre of mass in relation to the geometric centre of the rotor. In the paper, a mathematical model of the dynamic behaviour of a rigid rotor in active magnetic bearings was developed. The model is nonlinear and has five degrees of freedom and can only be solved numerically. The Newmark beta method and the Newton-Raphson method were used to solve the system of nonlinear differential equations. The results of the simulation showed the advantages of using active magnetic bearings for annulling sudden occurrences of unbalance in rotary machines.
{"title":"The annulling of the sudden appearance of an unbalance in rotary machines by using active magnetic bearings","authors":"Aleksandar Tomović, Milanko Damjanović, Radoslav Tomović, Janko Jovanović","doi":"10.30765/er.2308","DOIUrl":"https://doi.org/10.30765/er.2308","url":null,"abstract":"The application of magnetic bearings has become more frequent during the last 20 years and represents a significant aspect of improvements in the construction of machines with rotary motion. With the advancement of technology, the number of applications in which magnetic bearings have found their application is increasing. In this paper, it is shown how the effect of magnetic forces can annul the negative influence of unbalance, which suddenly appeared in a rotor supported in active magnetic bearings. Such cases may occur in operation due to breakage and rotor parts falling off (e.g., fan blades), which will lead to a sudden change in the mass balance of the rotor system and dislocation of the centre of mass in relation to the geometric centre of the rotor. In the paper, a mathematical model of the dynamic behaviour of a rigid rotor in active magnetic bearings was developed. The model is nonlinear and has five degrees of freedom and can only be solved numerically. The Newmark beta method and the Newton-Raphson method were used to solve the system of nonlinear differential equations. The results of the simulation showed the advantages of using active magnetic bearings for annulling sudden occurrences of unbalance in rotary machines.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135495353","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}
The present paper is devoted to fracture analysis of an inhomogeneous non-linear elastic beam configuration with three parallel longitudinal cracks. The material is continuously inhomogeneous along the beam height. The beam is subjected to four-point bending. The longitudinal fracture behavior is studied by applying the J-integral approach. Solutions to the J-integral are obtained for the three cracks. For this purpose, the curvature and the coordinates of neutral axes of the crack arms are determined by using the equations for equilibrium of the elementary forces in the cross-sections of different portions of the beam. The solutions to the J-integral are valid for arbitrary locations of the cracks along the beam height. Thus, the solutions are very useful for evaluating of the effects of locations of cracks on the fracture. The longitudinal fracture behavior is studied also in terms of the strain energy release rate in order to verify the solutions to the J-integral. Solutions to the strain energy release rate are derived for the three cracks by considering the complementary strain energy in the beam. The solutions to the J-integral are applied to evaluate the effects of locations of the cracks, the material inhomogeneity, the sizes of the beam cross-section, and the coordinates of the applications points of the external forces on the longitudinal fracture behavior of the beam.
{"title":"Triple longitudinal fracture of inhomogeneous beam under four-point bending","authors":"V. Ri̇zov","doi":"10.30765/er.2052","DOIUrl":"https://doi.org/10.30765/er.2052","url":null,"abstract":"The present paper is devoted to fracture analysis of an inhomogeneous non-linear elastic beam configuration with three parallel longitudinal cracks. The material is continuously inhomogeneous along the beam height. The beam is subjected to four-point bending. The longitudinal fracture behavior is studied by applying the J-integral approach. Solutions to the J-integral are obtained for the three cracks. For this purpose, the curvature and the coordinates of neutral axes of the crack arms are determined by using the equations for equilibrium of the elementary forces in the cross-sections of different portions of the beam. The solutions to the J-integral are valid for arbitrary locations of the cracks along the beam height. Thus, the solutions are very useful for evaluating of the effects of locations of cracks on the fracture. The longitudinal fracture behavior is studied also in terms of the strain energy release rate in order to verify the solutions to the J-integral. Solutions to the strain energy release rate are derived for the three cracks by considering the complementary strain energy in the beam. The solutions to the J-integral are applied to evaluate the effects of locations of the cracks, the material inhomogeneity, the sizes of the beam cross-section, and the coordinates of the applications points of the external forces on the longitudinal fracture behavior of the beam.","PeriodicalId":44022,"journal":{"name":"Engineering Review","volume":null,"pages":null},"PeriodicalIF":0.4,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69598834","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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