Pub Date : 2019-02-14DOI: 10.24423/ENGTRANS.970.20190214
Chuan Xiao
To characterize the dynamic behavior of typical asphalt pavements, which is induced by a complex loading system coupled with environmental effects, full-scale field tests were conducted on instrumented sections with embedded sensors. The impacts of vehicular loading factors and pavement temperature on strains at the bottom of asphalt layers were analyzed in the presence of in situ dynamic loading. According to orthogonal array tests, the impact levels of loading factors were quantified through analysis of variance. Furthermore, the temperature conversion factors of measured strain were explored using regression analysis. These results show that the measured strains present an asymmetry over time. The strain response goes up with increasing axle load and decreases with growing speed. Compared to the speed and the tire inflation pressure, the axle load plays a dominant role in strain responses. The estimated temperature conversion factor facilitates the strain conversion between non-standard temperature conditions and a required reference temperature.
{"title":"Evaluation of Measured Strain Responses to in Situ Vehicular Loading for Typical Asphalt Pavements","authors":"Chuan Xiao","doi":"10.24423/ENGTRANS.970.20190214","DOIUrl":"https://doi.org/10.24423/ENGTRANS.970.20190214","url":null,"abstract":"To characterize the dynamic behavior of typical asphalt pavements, which is induced by a complex loading system coupled with environmental effects, full-scale field tests were conducted on instrumented sections with embedded sensors. The impacts of vehicular loading factors and pavement temperature on strains at the bottom of asphalt layers were analyzed in the presence of in situ dynamic loading. According to orthogonal array tests, the impact levels of loading factors were quantified through analysis of variance. Furthermore, the temperature conversion factors of measured strain were explored using regression analysis. These results show that the measured strains present an asymmetry over time. The strain response goes up with increasing axle load and decreases with growing speed. Compared to the speed and the tire inflation pressure, the axle load plays a dominant role in strain responses. The \u0000estimated temperature conversion factor facilitates the strain conversion between non-standard temperature conditions and a required reference temperature.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42970891","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 : 2019-02-14DOI: 10.24423/ENGTRANS.946.20190214
S. Sahoo
Vibration characteristics of laminated composite stiffened hypar (hyperbolic paraboloid shell bounded by straight edges) with cut-out are analysed in terms of natural frequency and mode shapes. A finite element code is developed for the purpose by combining an eight noded curved shell element with a three noded curved beam element for stiffener. Finite element formulation is based on first order shear deformation theory and includes the effect of cross curvature. The isoparametric shell element used in the present model consists of eight nodes with five degrees of freedom per node while beam element has four degrees of freedom per node. The code is validated by solving benchmark problems available in the literature and comparing the results. The generalised Eigen value solution is chosen for the un-damped free vibration analysis. New results are presented for first five modes of natural frequency by varying boundary conditions, ply orientation and curvature of the shell. The results furnished here may be readily used by practicing engineers dealing with stiffened composite hypars with cut-outs.
{"title":"Characteristics of vibrating composite stiffened hypars with cut-out at different modes","authors":"S. Sahoo","doi":"10.24423/ENGTRANS.946.20190214","DOIUrl":"https://doi.org/10.24423/ENGTRANS.946.20190214","url":null,"abstract":"Vibration characteristics of laminated composite stiffened hypar (hyperbolic paraboloid shell bounded by straight edges) with cut-out are analysed in terms of natural frequency and mode shapes. A finite element code is developed for the purpose by combining an eight noded curved shell element with a three noded curved beam element for stiffener. Finite element formulation is based on first order shear deformation theory and includes the effect of cross curvature. The isoparametric shell element used in the present model consists of eight nodes with five degrees of freedom per node while beam element has four degrees of freedom per node. The code is validated by solving benchmark problems available in the literature and comparing the results. The generalised Eigen value solution is chosen for the un-damped free vibration analysis. New results are presented for first five modes of natural frequency by varying boundary conditions, ply orientation and curvature of the shell. The results furnished here may be readily used by practicing engineers dealing with stiffened composite hypars with cut-outs.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45944855","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 : 2018-12-20DOI: 10.24423/ENGTRANS.799.20181203
Ivan Yurievitch Zubko
A constitutive material spin tensor in the case of purely elastic finite-strain deformation is introduced for a two-dimensional orthotropic media using the minimizing principle applied to obtain the reloaded configuration of the material volume. This material spin explains the rotation of the orthonormal vector frame which coincides with the material symmetry axes in the initial configuration of the material volume and uniquely corresponds to a set of these axes in the current configuration although it does not coincide with the latter. The given definition is followed by the exact expression which includes the deformation gradient tensor, unit vectors of the initial material anisotropy axes and their axial parameters. This definition allows obtaining a new variant of decomposing any elastic finite-strain motion onto rigid and deformational parts and introducing the material corotational rate. The latter is used for the formulation of the anisotropic rate-type elastic law in the current configuration based on the strain measure which does not belong to the Seth-Hill family. For isotropic as well as for tetragonal media, the introduced material rotation tensor coincides with the rotation tensor from the polar decomposition of a deformation gradient.
{"title":"Material Spin and Finite-Strain Hypo-Elasticity for Two-Dimensional Orthotropic Media","authors":"Ivan Yurievitch Zubko","doi":"10.24423/ENGTRANS.799.20181203","DOIUrl":"https://doi.org/10.24423/ENGTRANS.799.20181203","url":null,"abstract":"A constitutive material spin tensor in the case of purely elastic finite-strain deformation is introduced for a two-dimensional orthotropic media using the minimizing principle applied to obtain the reloaded configuration of the material volume. This material spin explains the rotation of the orthonormal vector frame which coincides with the material symmetry axes in the initial configuration of the material volume and uniquely corresponds to a set of these axes in the current configuration although it does not coincide with the latter. The given definition is followed by the exact expression which includes the deformation gradient tensor, unit vectors of the initial material anisotropy axes and their axial parameters. This definition allows obtaining a new variant of decomposing any elastic finite-strain motion onto rigid and deformational parts and introducing the material corotational rate. The latter is used for the formulation of the anisotropic rate-type elastic law in the current configuration based on the strain measure which does not belong to the Seth-Hill family. For isotropic as well as for tetragonal media, the introduced material rotation tensor coincides with the rotation tensor from the polar decomposition of a deformation gradient.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42870866","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 : 2018-11-13DOI: 10.24423/ENGTRANS.942.20181113
G. Voyiadjis, P. Kattan
It is the aim of this work to develop and extend the theory of undamageable materials to graphene. An undamageable material is a material where the value of the damage variable remains zero throughout the deformation process. It is anticipated that the constitutive equations for undamageable graphene can be modeled with differential equations for the case of graphene. The equations are solved for three cases: n = 1, n = 2, and the general case of n. It is hoped that undamageable graphene can be achieved in the laboratory in the near future when the manufacturing technology advances so as to produce such materials.
{"title":"A Theory of Undamageable Graphene","authors":"G. Voyiadjis, P. Kattan","doi":"10.24423/ENGTRANS.942.20181113","DOIUrl":"https://doi.org/10.24423/ENGTRANS.942.20181113","url":null,"abstract":"It is the aim of this work to develop and extend the theory of undamageable materials to graphene. An undamageable material is a material where the value of the damage variable remains zero throughout the deformation process. It is anticipated that the constitutive equations for undamageable graphene can be modeled with differential equations for the case of graphene. The equations are solved for three cases: n = 1, n = 2, and the general case of n. It is hoped that undamageable graphene can be achieved in the laboratory in the near future when the manufacturing technology advances so as to produce such materials.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45646810","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 : 2018-11-13DOI: 10.24423/ENGTRANS.856.20181113
S. Łuczak
A review of the author’s own research on tilt measurements in mechatronic devices by means of micromachined accelerometers is presented. This comprehensive study addresses such issues as adjusting metrological properties of a tilt sensor for the application in a specific kind of a mechatronic device, systematizing problems pertaining to tilt measurements, applying various methods of decreasing uncertainty of tilt measurements, performing related experimental studies using custom test rigs, and building novel prototypes of tilt sensors. Due to the implementation of the proposed measurement techniques, considerations and novel ideas, it is possible to determine tilt either in a much simpler way, which translates to lower cost, or much more precisely, depending on particular requirements to be satisfied.
{"title":"Tilt Measurements in Mechatronic Devices and Mobile Microrobots","authors":"S. Łuczak","doi":"10.24423/ENGTRANS.856.20181113","DOIUrl":"https://doi.org/10.24423/ENGTRANS.856.20181113","url":null,"abstract":"A review of the author’s own research on tilt measurements in mechatronic devices by means of micromachined accelerometers is presented. This comprehensive study addresses such issues as adjusting metrological properties of a tilt sensor for the application in a specific kind of a mechatronic device, systematizing problems pertaining to tilt measurements, applying various methods of decreasing uncertainty of tilt measurements, performing related experimental studies using custom test rigs, and building novel prototypes of tilt sensors. Due to the implementation of the proposed measurement techniques, considerations and novel ideas, it is possible to determine tilt either in a much simpler way, which translates to lower cost, or much more precisely, depending on particular requirements to be satisfied.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46650431","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 : 2018-10-15DOI: 10.24423/ENGTRANS.850.20181017
X. Lv, Xiaorong Lv, Xiaojie Shi, Tingyu Wang
The force conditions in the steering system of the chassis under different conditions are analyzed theoretically for the independently designed and developed all-hydraulic crawler chassis. Using the multi-body dynamic simulation software RecurDyn, the chassis steering performance on sandy loam and clay pavements, and the steering performance under different steering radiuses on the sandy loam pavement are simulated and analysed dynamically respectively. The steering resistance moment is studied when the pavement conditions and steering radius are different. This research selects inside and outside crawler slip ratio as an index, and road conditions, speed and steering radius as factors to test the steering performance of all-hydraulic crawler chassis under different operating conditions. It is observed from the simulation results that during the pivot steering on the sandy loam, the drive torque and braking torque of the driving wheel are larger than on the clay ground. With the decrease of the steering radius, the torques of the left and right driving wheel are both gradually increasing. In the same steering radius, the torque of the outside driving wheel is larger than that of the inside driving wheel. The simulation results are consistent with the theoretical analysis results. In the steering performance test, the factors influencing the slippage rate on both sides of the crawler are such that the influence of the steering radius is greater than that pf the pavement condition and the pavement condition influence is greater than that of the speed. Among them, the steering radius has a significant influence on the slip ratio of the inside crawler, and an extremely significant influence on the slip ratio of the outside crawler. This research can provide a certain theoretical basis and technical reference for the development of hydraulic crawler chassis and optimization of the steering system.
{"title":"Experimental Verification of the Steering Performance of All-Hydraulic Crawler Chassis","authors":"X. Lv, Xiaorong Lv, Xiaojie Shi, Tingyu Wang","doi":"10.24423/ENGTRANS.850.20181017","DOIUrl":"https://doi.org/10.24423/ENGTRANS.850.20181017","url":null,"abstract":"The force conditions in the steering system of the chassis under different conditions are analyzed theoretically for the independently designed and developed all-hydraulic crawler chassis. Using the multi-body dynamic simulation software RecurDyn, the chassis steering performance on sandy loam and clay pavements, and the steering performance under different steering radiuses on the sandy loam pavement are simulated and analysed dynamically respectively. The steering resistance moment is studied when the pavement conditions and steering radius are different. This research selects inside and outside crawler slip ratio as an index, and road conditions, speed and steering radius as factors to test the steering performance of all-hydraulic crawler chassis under different operating conditions. It is observed from the simulation results that during the pivot steering on the sandy loam, the drive torque and braking torque of the driving wheel are larger than on the clay ground. With the decrease of the steering radius, the torques of the left and right driving wheel are both gradually increasing. In the same steering radius, the torque of the outside driving wheel is larger than that of the inside driving wheel. The simulation results are consistent with the theoretical analysis results. In the steering performance test, the factors influencing the slippage rate on both sides of the crawler are such that the influence of the steering radius is greater than that pf the pavement condition and the pavement condition influence is greater than that of the speed. Among them, the steering radius has a significant influence on the slip ratio of the inside crawler, and an extremely significant influence on the slip ratio of the outside crawler. This research can provide a certain theoretical basis and technical reference for the development of hydraulic crawler chassis and optimization of the steering system.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47925473","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 : 2018-10-04DOI: 10.24423/ENGTRANS.923.20181003
A. Baksa, I. Ecsedi
The object of this paper is Saint-Venant torsion of functionally graded anisotropic linearly elastic circular cylinder. The class of anisotropy considered has at least one plane of elastic symmetry normal to the axis of the circular cylinder. The elastic coefficients have radial dependence only. Here, we give the solution of Saint-Venant torsion problem for circular cylinder made of functionally graded anisotropic linearly elastic materials.
{"title":"Torsion of Functionally Graded Anisotropic Linearly Elastic Circular Cylinder","authors":"A. Baksa, I. Ecsedi","doi":"10.24423/ENGTRANS.923.20181003","DOIUrl":"https://doi.org/10.24423/ENGTRANS.923.20181003","url":null,"abstract":"The object of this paper is Saint-Venant torsion of functionally graded anisotropic linearly elastic circular cylinder. The class of anisotropy considered has at least one plane of elastic symmetry normal to the axis of the circular cylinder. The elastic coefficients have radial dependence only. Here, we give the solution of Saint-Venant torsion problem for circular cylinder made of functionally graded anisotropic linearly elastic materials.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41998055","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 : 2018-09-24DOI: 10.24423/ENGTRANS.723.20180924
G. Gaidulis, R. Kačianauskas, N. Kizilova, Yu. P. Romashov
In this paper, a two-dimensional (2D) model of the dynamics of mitral valve with chordae is developed based on in vivo data of the periodical motion of the valve leaflets digitized from the ultrasound imaging. The chordae are considered as viscoelastic springs described by the five-element rheological model. The model allows fast numerical computations of forces in the chordae and leaflets at different locations of the chordae of a different order. It can be used in real-time computations of the patient-specific geometry for optimal surgery planning when the mitral valve insufficiency is associated with broken chordae, and neochordae implantation is needed.
{"title":"A Mechanical Model of Heart Valves with Chordae for in Silico Real-Time Computations and Cardiac Surgery Planning","authors":"G. Gaidulis, R. Kačianauskas, N. Kizilova, Yu. P. Romashov","doi":"10.24423/ENGTRANS.723.20180924","DOIUrl":"https://doi.org/10.24423/ENGTRANS.723.20180924","url":null,"abstract":"In this paper, a two-dimensional (2D) model of the dynamics of mitral valve with chordae is developed based on in vivo data of the periodical motion of the valve leaflets digitized from the ultrasound imaging. The chordae are considered as viscoelastic springs described by the five-element rheological model. The model allows fast numerical computations of forces in the chordae and leaflets at different locations of the chordae of a different order. It can be used in real-time computations of the patient-specific geometry for optimal surgery planning when the mitral valve insufficiency is associated with broken chordae, and neochordae implantation is needed.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42297718","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 : 2018-09-20DOI: 10.24423/ENGTRANS.872.20180920
M. Podolski, Maciej Słabuszewski, B. Firlik, T. Staśkiewicz
Urban rail systems are characterized by low-radius curves which are very problematic to negotiate for modern rail vehicles. There are several inventions developed throughout time to cope with that problem. One group of them are bogie steering systems, responsible for the improvement of the alignment of carbodies in a curve, increasing ride comfort and reducing wheel and rail wear. The principle of those systems is to correct the relative settlement of bogies and carbodies during curve negotiations, to lower the angle of attack. One of such systems is described in this paper in terms of design, operation and verification. Some experimental and simulation results are presented and discussed.
{"title":"Bogie Steering System Improving Alignment of the Urban Railway Vehicle in a Track","authors":"M. Podolski, Maciej Słabuszewski, B. Firlik, T. Staśkiewicz","doi":"10.24423/ENGTRANS.872.20180920","DOIUrl":"https://doi.org/10.24423/ENGTRANS.872.20180920","url":null,"abstract":"Urban rail systems are characterized by low-radius curves which are very problematic to negotiate for modern rail vehicles. There are several inventions developed throughout time to cope with that problem. One group of them are bogie steering systems, responsible for the improvement of the alignment of carbodies in a curve, increasing ride comfort and reducing wheel and rail wear. The principle of those systems is to correct the relative settlement of bogies and carbodies during curve negotiations, to lower the angle of attack. One of such systems is described in this paper in terms of design, operation and verification. Some experimental and simulation results are presented and discussed.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41557992","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 : 2018-09-20DOI: 10.24423/ENGTRANS.884.20180928
Chandrashekar Mahadevaiah, S. Prasad
The machining of titanium has been understood to be challenging and costly due to its material properties such as low thermal conductivity, low modulus of elasticity, high strength at elevated temperatures and chemical reactivity. This work aims to study the effect of iron as a partial substitution along with cobalt binder as the tool material for machining of titanium alloy. In this work, iron-rich binder tool (WC-Co-Fe) and cobalt binder tool (WC-Co) samples were produced by powder metallurgy route using powders with a mean particle size of less than 0.5 μm. Next, the evaluation of mechanical properties and phase analysis were performed. Turning experiments were conducted at various cutting speeds, feed and depth of cut (DOC), to evaluate the effects of iron-rich binder on flank wear, cutting forces and cutting temperature. The obtained results of turning experiments reveal that iron-rich binder tends to increase cutting performance in comparison to conventional WC-Co composite cutting tools.
{"title":"Evaluation of Cutting Forces and Temperature of Iron-Rich Binder Carbide Tool in Turning of Titanium","authors":"Chandrashekar Mahadevaiah, S. Prasad","doi":"10.24423/ENGTRANS.884.20180928","DOIUrl":"https://doi.org/10.24423/ENGTRANS.884.20180928","url":null,"abstract":"The machining of titanium has been understood to be challenging and costly due to its material properties such as low thermal conductivity, low modulus of elasticity, high strength at elevated temperatures and chemical reactivity. This work aims to study the effect of iron as a partial substitution along with cobalt binder as the tool material for machining of titanium alloy. In this work, iron-rich binder tool (WC-Co-Fe) and cobalt binder tool (WC-Co) samples were produced by powder metallurgy route using powders with a mean particle size of less than 0.5 μm. Next, the evaluation of mechanical properties and phase analysis were performed. Turning experiments were conducted at various cutting speeds, feed and depth of cut (DOC), to evaluate the effects of iron-rich binder on flank wear, cutting forces and cutting temperature. \u0000The obtained results of turning experiments reveal that iron-rich binder tends to increase cutting performance in comparison to conventional WC-Co composite cutting tools.","PeriodicalId":38552,"journal":{"name":"Engineering Transactions","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43010888","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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