Pub Date : 2020-02-29DOI: 10.15866/irease.v13i1.17165
Dam Viet Phuong, Quoc Tru Vu, A. Nguyen
{"title":"Effects of Stiffness and the Variation of Center of Mass on Rocket Motion","authors":"Dam Viet Phuong, Quoc Tru Vu, A. Nguyen","doi":"10.15866/irease.v13i1.17165","DOIUrl":"https://doi.org/10.15866/irease.v13i1.17165","url":null,"abstract":"","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"14 1","pages":"16"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72727191","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 : 2020-02-29DOI: 10.15866/irease.v13i1.18108
E. S. Ramya, P. Lovaraju, I. D. Murthy, S. Thanigaiarasu, E. Rathakrishnan
Experimental and computational investigations have been conducted to characterize the flow field in the supersonic ejector, with and without secondary inlets of two sizes, at stagnation pressures of 2, 2.5, 3, 4 and 5 bar. In the first case, four secondary inlet openings each with 5 mm diameter are provided on the suction chamber circumferentially. In the second case, four secondary inlet openings each with 10 mm diameter are provided on the suction chamber circumferentially. These two cases are investigated separately, at all the stagnation pressures. The wall pressure variation is validated based on the k-ω SST turbulent model with experimentally measured wall pressure distribution at 2 bar, without secondary inlet flow. Suction is found to increase with the increase of stagnation pressure in the suction chamber. The inducted mass flow promotes the mixing in the shock-train zone, by triggering the significant momentum exchange between the primary flow and secondary flow. Results show that the pressure recovery takes place as the flow enters the divergent portion of ejector.
{"title":"Experimental and Computational Investigations on Flow Characteristics of Supersonic Ejector","authors":"E. S. Ramya, P. Lovaraju, I. D. Murthy, S. Thanigaiarasu, E. Rathakrishnan","doi":"10.15866/irease.v13i1.18108","DOIUrl":"https://doi.org/10.15866/irease.v13i1.18108","url":null,"abstract":"Experimental and computational investigations have been conducted to characterize the flow field in the supersonic ejector, with and without secondary inlets of two sizes, at stagnation pressures of 2, 2.5, 3, 4 and 5 bar. In the first case, four secondary inlet openings each with 5 mm diameter are provided on the suction chamber circumferentially. In the second case, four secondary inlet openings each with 10 mm diameter are provided on the suction chamber circumferentially. These two cases are investigated separately, at all the stagnation pressures. The wall pressure variation is validated based on the k-ω SST turbulent model with experimentally measured wall pressure distribution at 2 bar, without secondary inlet flow. Suction is found to increase with the increase of stagnation pressure in the suction chamber. The inducted mass flow promotes the mixing in the shock-train zone, by triggering the significant momentum exchange between the primary flow and secondary flow. Results show that the pressure recovery takes place as the flow enters the divergent portion of ejector.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"44 1","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84629644","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 : 2020-02-29DOI: 10.15866/irease.v13i1.17849
F. Ismagilov, Aleksey L. Zherebtsov, V. Vavilov, I. Sayakhov
{"title":"Design and Experimental Investigation of BLDC Motor for Aircraft Electromechanical Actuator","authors":"F. Ismagilov, Aleksey L. Zherebtsov, V. Vavilov, I. Sayakhov","doi":"10.15866/irease.v13i1.17849","DOIUrl":"https://doi.org/10.15866/irease.v13i1.17849","url":null,"abstract":"","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"80 1","pages":"10"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77245223","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 : 2020-02-29DOI: 10.15866/irease.v13i1.18282
Mohammad Saeed Samara, A. Vashishtha, Yasumasa Watanabe, Kojiro Suzuki
{"title":"Flow-Field and Performance Study of Coaxial Supersonic Nozzles Operating in Hypersonic Environment","authors":"Mohammad Saeed Samara, A. Vashishtha, Yasumasa Watanabe, Kojiro Suzuki","doi":"10.15866/irease.v13i1.18282","DOIUrl":"https://doi.org/10.15866/irease.v13i1.18282","url":null,"abstract":"","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"4 1","pages":"25"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89933014","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 : 2019-12-31DOI: 10.15866/irease.v12i6.16910
V. Tynchenko, A. Milov, V. Tynchenko, V. Bukhtoyarov, V. Kukartsev
The aim of this work is to develop an intelligent method for controlling the induction soldering process of spacecraft’s thin-walled aluminum waveguide tracks. This new control method is based on the use of intelligent data analysis in order to determine the optimal control algorithms for product heating and the workpiece motion control with optimal coefficients based on the operational data of the induction soldering technological process. The paper presents a mathematical formulation of the intelligent control problem. As part of this work, such intellectual methods have been chosen for comparison as a method based on a fuzzy logic, artificial neural networks, and a neuro-fuzzy controller. Based on experimental data on real technological processes of induction soldering, a comparative analysis of the effectiveness of the proposed approach has been carried out. The results of experimental studies have shown that the control method of the induction soldering technological process based on artificial neural networks has the highest efficiency. In addition, based on experimental data of real technological processes, the most effective structure of an artificial neural network has been determined. The highest recognition accuracy has been provided by an artificial neural network with five artificial neurons on each one of five hidden layers. Experimental quality control of the obtained artificial neural network has been carried out on three different waveguide tracks assemblies with different tube thicknesses: 58×25 mm, 35×15 mm, 19×9.5 mm. The results of the experimental verification have showed that for all the three waveguide tracks assemblies high-quality soldered joints have been obtained. The integrated application of intelligent technologies for controlling the technological process of induction soldering of thin-walled aluminum waveguide tracks could significantly improve the quality of permanently formed connections, as well as eliminate errors associated with human factor. Further research will focus on the intellectualization of other technological processes for creating permanent connections, such as electron beam welding, diffusion welding, etc. The results of this work clearly show the effectiveness of the proposed concept of intellectualization, so it is advisable to extend it to a wider range of technological processes.
本工作的目的是开发一种控制航天器薄壁铝波导轨道感应焊接过程的智能方法。这种新的控制方法是基于智能数据分析，以感应焊接工艺过程的运行数据为基础，确定产品加热的最优控制算法和工件运动控制的最优系数。本文给出了智能控制问题的数学表达式。作为这项工作的一部分，这种智能方法被选择作为基于模糊逻辑、人工神经网络和神经模糊控制器的方法进行比较。基于感应焊实际工艺过程的实验数据，对所提方法的有效性进行了对比分析。实验研究结果表明，基于人工神经网络的感应焊接工艺过程控制方法具有最高的效率。此外，根据实际工艺过程的实验数据，确定了最有效的人工神经网络结构。在5个隐藏层的每一层都有5个人工神经元的人工神经网络提供了最高的识别精度。对所获得的人工神经网络进行了实验质量控制，并对三种不同管厚的波导轨迹组件:58×25 mm, 35×15 mm, 19×9.5 mm进行了实验质量控制。实验验证结果表明，三种波导波导组件均获得了高质量的焊接接头。集成应用智能技术控制薄壁铝波导磁道感应焊接工艺过程，可以显著提高永久形成连接的质量，消除人为因素带来的误差。进一步的研究将集中在创造永久连接的其他技术过程的智能化，如电子束焊接、扩散焊接等。这项工作的结果清楚地表明了所提出的智能化概念的有效性，因此将其扩展到更广泛的技术过程是可取的。
{"title":"Intellectualizing the Process of Waveguide Tracks Induction Soldering for Spacecrafts","authors":"V. Tynchenko, A. Milov, V. Tynchenko, V. Bukhtoyarov, V. Kukartsev","doi":"10.15866/irease.v12i6.16910","DOIUrl":"https://doi.org/10.15866/irease.v12i6.16910","url":null,"abstract":"The aim of this work is to develop an intelligent method for controlling the induction soldering process of spacecraft’s thin-walled aluminum waveguide tracks. This new control method is based on the use of intelligent data analysis in order to determine the optimal control algorithms for product heating and the workpiece motion control with optimal coefficients based on the operational data of the induction soldering technological process. The paper presents a mathematical formulation of the intelligent control problem. As part of this work, such intellectual methods have been chosen for comparison as a method based on a fuzzy logic, artificial neural networks, and a neuro-fuzzy controller. Based on experimental data on real technological processes of induction soldering, a comparative analysis of the effectiveness of the proposed approach has been carried out. The results of experimental studies have shown that the control method of the induction soldering technological process based on artificial neural networks has the highest efficiency. In addition, based on experimental data of real technological processes, the most effective structure of an artificial neural network has been determined. The highest recognition accuracy has been provided by an artificial neural network with five artificial neurons on each one of five hidden layers. Experimental quality control of the obtained artificial neural network has been carried out on three different waveguide tracks assemblies with different tube thicknesses: 58×25 mm, 35×15 mm, 19×9.5 mm. The results of the experimental verification have showed that for all the three waveguide tracks assemblies high-quality soldered joints have been obtained. The integrated application of intelligent technologies for controlling the technological process of induction soldering of thin-walled aluminum waveguide tracks could significantly improve the quality of permanently formed connections, as well as eliminate errors associated with human factor. Further research will focus on the intellectualization of other technological processes for creating permanent connections, such as electron beam welding, diffusion welding, etc. The results of this work clearly show the effectiveness of the proposed concept of intellectualization, so it is advisable to extend it to a wider range of technological processes.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"46 1","pages":"280-289"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74355542","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 : 2019-12-31DOI: 10.15866/irease.v12i6.17333
M. Fioriti, V. Vercella
The present work proposes a new parametric cost model in order to assess civil aircraft maintenance cost during the initial phase of aircraft design. The model focuses on defined maintenance activities, i.e. line and base maintenance, providing cost estimating relationships for the two cost items under study. The proposed cost model represents an updated alternative tool compared to the state-of-the-art models for civil aircraft maintenance costs estimation. It is based on current aircraft data provided by the International Air Transport Association and it may be useful to assess maintenance cost for new projects during aircraft conceptual design. The collinearity analysis is included in order to select independent cost drivers. The results of the developed model are in good accordance with other reference cost data provided by an independent source. The latter refer to aircraft models not considered in International Air Transport Association reports and adopting new technologies (such as composite structural materials) within their development. The analysis of the results obtained demonstrates that the application of proper corrective coefficients may lead to a maintenance cost estimation model for innovative aircraft configurations based on present architectures.
{"title":"A Parametric Cost Model for Estimating Civil Aircraft Line and Base Maintenance","authors":"M. Fioriti, V. Vercella","doi":"10.15866/irease.v12i6.17333","DOIUrl":"https://doi.org/10.15866/irease.v12i6.17333","url":null,"abstract":"The present work proposes a new parametric cost model in order to assess civil aircraft maintenance cost during the initial phase of aircraft design. The model focuses on defined maintenance activities, i.e. line and base maintenance, providing cost estimating relationships for the two cost items under study. The proposed cost model represents an updated alternative tool compared to the state-of-the-art models for civil aircraft maintenance costs estimation. It is based on current aircraft data provided by the International Air Transport Association and it may be useful to assess maintenance cost for new projects during aircraft conceptual design. The collinearity analysis is included in order to select independent cost drivers. The results of the developed model are in good accordance with other reference cost data provided by an independent source. The latter refer to aircraft models not considered in International Air Transport Association reports and adopting new technologies (such as composite structural materials) within their development. The analysis of the results obtained demonstrates that the application of proper corrective coefficients may lead to a maintenance cost estimation model for innovative aircraft configurations based on present architectures.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"4 1","pages":"250-260"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80020791","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 : 2019-12-31DOI: 10.15866/irease.v12i6.18584
L. Toscano
Many physical problems, such as in fluidodynamics or aerospace applications, are governed by systems of differential equations with nonlinearity of nonlocal type, too. Obviously, the main question is the existence of the solutions of such problems but it is also interesting to analyze the properties of these solutions, when it is possible. In order to find the existence of the solutions and the related properties, this paper proposes to adopt a theorem previously proved by the same author. Following a variational approach via fibering method in the paper a class of variational equations with non-coercive main part has been used to solve differential equations of some interesting applications.
{"title":"Existence and Properties of the Solutions via Fibering Method of a Class of Variational Equations with Non-Coercive Main Part with Some Applications","authors":"L. Toscano","doi":"10.15866/irease.v12i6.18584","DOIUrl":"https://doi.org/10.15866/irease.v12i6.18584","url":null,"abstract":"Many physical problems, such as in fluidodynamics or aerospace applications, are governed by systems of differential equations with nonlinearity of nonlocal type, too. Obviously, the main question is the existence of the solutions of such problems but it is also interesting to analyze the properties of these solutions, when it is possible. In order to find the existence of the solutions and the related properties, this paper proposes to adopt a theorem previously proved by the same author. Following a variational approach via fibering method in the paper a class of variational equations with non-coercive main part has been used to solve differential equations of some interesting applications.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"16 1","pages":"302-314"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81513791","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 : 2019-12-31DOI: 10.15866/irease.v12i6.17748
V. Vavilov, L. Papini, F. Ismagilov, Shoujun Song, V. Ayguzina
{"title":"High-Speed Permanent-Magnet Generator with Controlled Magnetic Flux for Aerospace Application","authors":"V. Vavilov, L. Papini, F. Ismagilov, Shoujun Song, V. Ayguzina","doi":"10.15866/irease.v12i6.17748","DOIUrl":"https://doi.org/10.15866/irease.v12i6.17748","url":null,"abstract":"","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"4 1","pages":"290"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87636483","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 : 2019-12-31DOI: 10.15866/irease.v12i6.16587
J. Jang, Jehong Park
This paper aims to study a modeling technique for flutter analysis of subsonic aircraft by using finite element analysis including flight control failures. By applying distribution of stiffness of dynamic characteristics model as a beam element and distribution of mass as a concentrated mass, the configuration of aircraft idealized. The aerodynamic force model includes all lifting surfaces, fuselage and utilized doublet lattice method in consideration of mutual interference effect between lifting surface and lifting face and lifting surface and fuselage, in empty fuel condition, to 1.74 Vd and in full fuel condition, to 1.71 Vd. There has been no aeroelastic instability on the subsonic aircraft. As a result of flutter analysis based on hinge damage of control surface, it has been proved that it is safe to damages. However, it is required to observe carefully whether the hinge of rudder has been damaged, since the flutter seed decreases significantly when there is one. The control system that has major impact on the aeroelastic characteristic of subsonic aircraft has been modelled to represent the rotational mode of rigid body and elasticity. The flutter analysis has been conducted on empty fuel condition, full fuel condition, changes in volume of mass balance, cases of hinge damage and its results.
{"title":"Stability Analysis of a Subsonic Aircraft with Flight Control System Including Structural Damage","authors":"J. Jang, Jehong Park","doi":"10.15866/irease.v12i6.16587","DOIUrl":"https://doi.org/10.15866/irease.v12i6.16587","url":null,"abstract":"This paper aims to study a modeling technique for flutter analysis of subsonic aircraft by using finite element analysis including flight control failures. By applying distribution of stiffness of dynamic characteristics model as a beam element and distribution of mass as a concentrated mass, the configuration of aircraft idealized. The aerodynamic force model includes all lifting surfaces, fuselage and utilized doublet lattice method in consideration of mutual interference effect between lifting surface and lifting face and lifting surface and fuselage, in empty fuel condition, to 1.74 Vd and in full fuel condition, to 1.71 Vd. There has been no aeroelastic instability on the subsonic aircraft. As a result of flutter analysis based on hinge damage of control surface, it has been proved that it is safe to damages. However, it is required to observe carefully whether the hinge of rudder has been damaged, since the flutter seed decreases significantly when there is one. The control system that has major impact on the aeroelastic characteristic of subsonic aircraft has been modelled to represent the rotational mode of rigid body and elasticity. The flutter analysis has been conducted on empty fuel condition, full fuel condition, changes in volume of mass balance, cases of hinge damage and its results.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"36 1","pages":"271-279"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90505444","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 : 2019-12-31DOI: 10.15866/irease.v12i6.16215
Mohanad Alnuaimi, M. Perhinschi, Ghassan Al-Sinbol
A framework based on the artificial immune system (AIS) paradigm is proposed in this paper for correcting position and velocity estimations for autonomous flight vehicles in environments where global navigation satellite systems (GNSS) are not available. The AIS consists of sets of memory cells built under normal conditions when all sensor systems function properly. The memory cells mimic the functionality of memory T-cells and B-cell capable of encoding and storing information about the invading antigens and the needed antibodies. This information is used to enhance the response of the innate immune system with an adaptive component that is expected to accelerate and intensify the immune response when subsequent infections with the same antigen are experienced. The artificial memory cells are constructed with two parts. One represents the antigen and is a collection of instantaneous measurements of relevant features that characterize the dynamics of the system and are the basis of the position and velocity estimation. The other represents the antibodies and is a set of instantaneous estimation errors that are viewed as necessary corrections for the estimation. During GNSS-denied operation, the current measured features are matched against the AIS antigens and the corresponding corrections are extracted and used to tune the outputs of the position and velocity estimation algorithm for feedback control. The functionality of the proposed methodology and its promising potential is successfully illustrated using the West Virginia University unmanned aerial system simulation environment.
{"title":"Immunity-Based Framework for Autonomous Flight in GNSS-Denied Environment","authors":"Mohanad Alnuaimi, M. Perhinschi, Ghassan Al-Sinbol","doi":"10.15866/irease.v12i6.16215","DOIUrl":"https://doi.org/10.15866/irease.v12i6.16215","url":null,"abstract":"A framework based on the artificial immune system (AIS) paradigm is proposed in this paper for correcting position and velocity estimations for autonomous flight vehicles in environments where global navigation satellite systems (GNSS) are not available. The AIS consists of sets of memory cells built under normal conditions when all sensor systems function properly. The memory cells mimic the functionality of memory T-cells and B-cell capable of encoding and storing information about the invading antigens and the needed antibodies. This information is used to enhance the response of the innate immune system with an adaptive component that is expected to accelerate and intensify the immune response when subsequent infections with the same antigen are experienced. The artificial memory cells are constructed with two parts. One represents the antigen and is a collection of instantaneous measurements of relevant features that characterize the dynamics of the system and are the basis of the position and velocity estimation. The other represents the antibodies and is a set of instantaneous estimation errors that are viewed as necessary corrections for the estimation. During GNSS-denied operation, the current measured features are matched against the AIS antigens and the corresponding corrections are extracted and used to tune the outputs of the position and velocity estimation algorithm for feedback control. The functionality of the proposed methodology and its promising potential is successfully illustrated using the West Virginia University unmanned aerial system simulation environment.","PeriodicalId":14462,"journal":{"name":"International Review of Aerospace Engineering","volume":"28 1","pages":"239-249"},"PeriodicalIF":0.0,"publicationDate":"2019-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83601628","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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