The closed-form representations of surface Green’s functions corresponding to the action of a concentrated force applied at the boundary of a region occupied by a particular class of compressible hyperelastic materials of harmonic type, has been derived. In our analysis, we consider both a bounded region in the form of a circular disk and an unbounded region with either an elliptical hole or a parabolic boundary.
{"title":"Surface Green’s functions in finite plane elastostatics of harmonic materials","authors":"X. Wang, P. Schiavone","doi":"10.24423/AOM.2834","DOIUrl":"https://doi.org/10.24423/AOM.2834","url":null,"abstract":"The closed-form representations of surface Green’s functions corresponding to the action of a concentrated force applied at the boundary of a region occupied by a particular class of compressible hyperelastic materials of harmonic type, has been derived. In our analysis, we consider both a bounded region in the form of a circular disk and an unbounded region with either an elliptical hole or a parabolic boundary.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2018-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47920997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Analytical solutions are derived to analyze elastic limit heat loads in tubes subjected to periodic surface temperatures. The tube is initially at zero temperature and for the times greater than zero one of the surfaces of the cylinder is subject to a periodic boundary condition while the other surface is insulated. For the transient temperature distribution, the heat conduction equation is solved by using Duhamel’s theorem. The uncoupled theory of thermoelasticity is used as the cylinder is heated or cooled slowly. Tresca’s yield criterion is used to monitor the yielding of the tube. The generalized plane strain condition is assumed. It is observed that yielding always occurs at the surface subject to a periodic boundary condition. It is also observed that, depending on the material properties of the tube and the amplitude of the boundary condition, yielding commences with different stress states.
{"title":"Analyses of elastic limit heat loads in thick walled tubes subjected to periodic surface temperatures: analytical treatment","authors":"T. Apatay, A. Eraslan","doi":"10.24423/AOM.2831","DOIUrl":"https://doi.org/10.24423/AOM.2831","url":null,"abstract":"Analytical solutions are derived to analyze elastic limit heat loads in tubes subjected to periodic surface temperatures. The tube is initially at zero temperature and for the times greater than zero one of the surfaces of the cylinder is subject to a periodic boundary condition while the other surface is insulated. For the transient temperature distribution, the heat conduction equation is solved by using Duhamel’s theorem. The uncoupled theory of thermoelasticity is used as the cylinder is heated or cooled slowly. Tresca’s yield criterion is used to monitor the yielding of the tube. The generalized plane strain condition is assumed. It is observed that yielding always occurs at the surface subject to a periodic boundary condition. It is also observed that, depending on the material properties of the tube and the amplitude of the boundary condition, yielding commences with different stress states.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2018-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41316988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper the transverse vibrations of a vertical cable carrying a concentrated mass at its lower end and moving slowly vertically within the host structure are considered. It is assumed that longitudinal inertia of the cable can be neglected, with the longitudinal motion of the concentrated mass coupled with the lateral motion of the cable. An expansion of the lateral displacement of a cable in terms of approximating functions is used. The excitation acting upon the cable-mass system is a base-motion excitation due to the sway motion of a host tall structure. Such a motion of a structure often results due to action of the wind, hence it may be adequately idealized as a narrow-band random process. The narrow-band process is represented as the output of a system of two linear filters to the input in a form of a Gaussian white noise process. The non-linear problem is dealt with by an equivalent linearization technique, where the original non-linear system is replaced with an equivalent linear one, whose coefficients are determined from the condition of minimization of a mean-square error between the non-linear and the linear systems. The mean value and variance of the transverse displacement of the cable as well as those of the longitudinal motion of the lumped mass are determined with the aid of an equivalent linear system and compared with the response of the original non-linear system subjected to the deterministic harmonic excitation.
{"title":"Equivalent linearization technique in nonlinear stochastic dynamics of a cable-mass system with time-varying length","authors":"Hanna Weber, R. Iwankiewicz, S. Kaczmarczyk","doi":"10.24423/AOM.3142","DOIUrl":"https://doi.org/10.24423/AOM.3142","url":null,"abstract":"In this paper the transverse vibrations of a vertical cable carrying a concentrated mass at its lower end and moving slowly vertically within the host structure are considered. It is assumed that longitudinal inertia of the cable can be neglected, with the longitudinal motion of the concentrated mass coupled with the lateral motion of the cable. An expansion of the lateral displacement of a cable in terms of approximating functions is used. The excitation acting upon the cable-mass system is a base-motion excitation due to the sway motion of a host tall structure. Such a motion of a structure often results due to action of the wind, hence it may be adequately idealized as a narrow-band random process. The narrow-band process is represented as the output of a system of two linear filters to the input in a form of a Gaussian white noise process. The non-linear problem is dealt with by an equivalent linearization technique, where the original non-linear system is replaced with an equivalent linear one, whose coefficients are determined from the condition of minimization of a mean-square error between the non-linear and the linear systems. The mean value and variance of the transverse displacement of the cable as well as those of the longitudinal motion of the lumped mass are determined with the aid of an equivalent linear system and compared with the response of the original non-linear system subjected to the deterministic harmonic excitation.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68939016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Z. Rahimi, G. Rezazadeh, W. Sumelka, Xiao-jun Yang
Fractional derivative models (FDMs) result from introduction of fractional derivatives (FDs) into the governing equations of the differential operator type of linear solid materials. FDMs are more general than those of integer derivative models (IDMs) so they are more fixable to describe physical phenomena. In this paper the inhomogeneous nonlocal theory has been introduced based on conformable fractional derivatives (CFD) to study the critical point instability of micro/nano beams under a distributed variable-pressure force. The phase of distributed variable-pressure force is used for electrostatic force, electromagnetic force and so on. This model has two free parameters: i) parameter to control the order of inhomogeneity in constitutive relations that gives a general form to the model, and ii) a nonlocal parameter to consider size dependence effects in micron and sub-micron scales. As a case study the theory has been used to model micro cantilever (C-F) and doubly-clamped (C-C) silicon beams under a distributed uniform electrostatic force in the presence of von-Karman nonlinearity and their static critical point (static pull-in instability), moreover, effects of different inhomogeneity have been shown on the pull-in instability.
{"title":"A study of critical point instability of micro and nano beams under a distributed variable-pressure force in the framework of the inhomogeneous non-linear nonlocal theory","authors":"Z. Rahimi, G. Rezazadeh, W. Sumelka, Xiao-jun Yang","doi":"10.24423/AOM.2660","DOIUrl":"https://doi.org/10.24423/AOM.2660","url":null,"abstract":"Fractional derivative models (FDMs) result from introduction of fractional derivatives (FDs) into the governing equations of the differential operator type of linear solid materials. FDMs are more general than those of integer derivative models (IDMs) so they are more fixable to describe physical phenomena. In this paper the inhomogeneous nonlocal theory has been introduced based on conformable fractional derivatives (CFD) to study the critical point instability of micro/nano beams under a distributed variable-pressure force. The phase of distributed variable-pressure force is used for electrostatic force, electromagnetic force and so on. This model has two free parameters: i) parameter to control the order of inhomogeneity in constitutive relations that gives a general form to the model, and ii) a nonlocal parameter to consider size dependence effects in micron and sub-micron scales. As a case study the theory has been used to model micro cantilever (C-F) and doubly-clamped (C-C) silicon beams under a distributed uniform electrostatic force in the presence of von-Karman nonlinearity and their static critical point (static pull-in instability), moreover, effects of different inhomogeneity have been shown on the pull-in instability.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45580753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Two-dimensional foam is a type of cellular solid materials containing a high volume fraction of pores. The thermal behavior of foam depends strongly on its microscopic structure. In this study, a two-dimensional closed-cell foam model containing randomly distributed air voids and solid walls is designed via a Voronoi diagram enhanced by the shrinking technique to approximately represent the real foam structure. The porosity, pore size and solid wall thickness of the established random foam structure is examined by introducing the so-called shrinking ratio. Subsequently, the effective thermal conductivity of the rebuilt foam model is numerically presented through the finite element analysis. The numerical results obtained are verified by comparison with the available theoretical and experimental results. In the analysis, the effects of porosity, number of pores and thermal conductivity of solid phase in foam structures are investigated respectively to reveal the relationship of geometric parameters and thermal properties of solid phase with effective thermal conductivity of the foam.
{"title":"Analysing effective thermal conductivity of 2D closed-cell foam based on shrunk Voronoi tessellations","authors":"Hui Wang, B. Liu, Y.-X. Kang, Q. Qin","doi":"10.24423/AOM.2708","DOIUrl":"https://doi.org/10.24423/AOM.2708","url":null,"abstract":"Two-dimensional foam is a type of cellular solid materials containing a high volume fraction of pores. The thermal behavior of foam depends strongly on its microscopic structure. In this study, a two-dimensional closed-cell foam model containing randomly distributed air voids and solid walls is designed via a Voronoi diagram enhanced by the shrinking technique to approximately represent the real foam structure. The porosity, pore size and solid wall thickness of the established random foam structure is examined by introducing the so-called shrinking ratio. Subsequently, the effective thermal conductivity of the rebuilt foam model is numerically presented through the finite element analysis. The numerical results obtained are verified by comparison with the available theoretical and experimental results. In the analysis, the effects of porosity, number of pores and thermal conductivity of solid phase in foam structures are investigated respectively to reveal the relationship of geometric parameters and thermal properties of solid phase with effective thermal conductivity of the foam.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44373194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the wave fields induced by both tensile and shear displacement dislocations in stratified fluid-saturated porous media are computed by using the reflection and transmission matrix method. The components of the source discontinuity vector across the source plane to describe those tensile and shear faults are explicitly displayed by using the surface vector harmonics. Numerical examples for a two layer model subjected to tensile and shear dislocations are provided. From the waveforms of surface displacements, the arrivals of transmitted and converted PS and SP waves at the interface of the two layer model can be clearly observed.
{"title":"Wave fields in the stratified fluid-saturated porous half-space induced by dislocation sources","authors":"Y. Song, J. Shi","doi":"10.24423/AOM.2704","DOIUrl":"https://doi.org/10.24423/AOM.2704","url":null,"abstract":"In this study, the wave fields induced by both tensile and shear displacement dislocations in stratified fluid-saturated porous media are computed by using the reflection and transmission matrix method. The components of the source discontinuity vector across the source plane to describe those tensile and shear faults are explicitly displayed by using the surface vector harmonics. Numerical examples for a two layer model subjected to tensile and shear dislocations are provided. From the waveforms of surface displacements, the arrivals of transmitted and converted PS and SP waves at the interface of the two layer model can be clearly observed.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45673531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents the results of large eddy simulation/conditional moment closure (LES-CMC) computations of a turbulent flame in oxy-combustion regimes complemented by 0D-CMC analysis. The fuel is pure hydrogen and it issues into a hot oxidiser stream which is a mixture of oxygen and water vapour. The flame is initiated by a spark, then it spreads and propagates through the domain and eventually stabilises as a lifted or attached one. The present problem offers new challenges to combustion modelling as the observed combustion process is strongly unsteady. In cases of large content of oxygen in the oxidiser stream the flame has very high temperature (≈ 3000 K) and large temperature/density variations. Nevertheless, it is shown that LES-CMC simulations are stable in such conditions and can be successfully applied to oxy-combustion studies. We analyse the dependence of the flame temperatures and lift-off height of the flames LH on the oxidiser composition and chemical kinetics. It is shown that both these factors may affect the flame behaviour. We identified the conditions in which LH exhibits a linear dependence on the oxidiser composition independently of applied chemical kinetics, and the regimes where the LH changes in a non-linear manner and strongly depends on the chemical kinetics.
{"title":"Numerical study of a turbulent hydrogen flame in oxy-combustion regimes","authors":"A. Wawrzak, A. Tyliszczak","doi":"10.24423/AOM.2298","DOIUrl":"https://doi.org/10.24423/AOM.2298","url":null,"abstract":"This paper presents the results of large eddy simulation/conditional moment closure (LES-CMC) computations of a turbulent flame in oxy-combustion regimes complemented by 0D-CMC analysis. The fuel is pure hydrogen and it issues into a hot oxidiser stream which is a mixture of oxygen and water vapour. The flame is initiated by a spark, then it spreads and propagates through the domain and eventually stabilises as a lifted or attached one. The present problem offers new challenges to combustion modelling as the observed combustion process is strongly unsteady. In cases of large content of oxygen in the oxidiser stream the flame has very high temperature (≈ 3000 K) and large temperature/density variations. Nevertheless, it is shown that LES-CMC simulations are stable in such conditions and can be successfully applied to oxy-combustion studies. We analyse the dependence of the flame temperatures and lift-off height of the flames LH on the oxidiser composition and chemical kinetics. It is shown that both these factors may affect the flame behaviour. We identified the conditions in which LH exhibits a linear dependence on the oxidiser composition independently of applied chemical kinetics, and the regimes where the LH changes in a non-linear manner and strongly depends on the chemical kinetics.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68937971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Bobinski, G. Sobieraj, M. Psarski, Grzegorz Celichowski, J. Rokicki
In this paper, we present static and dynamic interactions of water droplets with a micro-structured surface that exhibits hydrophobic properties. Droplets with two different diameters ( D 0 = 0.6 ± 0.1 mm and D 0 = 2.6 ± 0.1 mm) were studied for impact velocities in the range of 0.1 ÷ 2.5 m/s. This allowed to investigate the influence of gravity on the collision behavior during an impact. The main result of the present research is the determination of the critical conditions for consecutive transitions leading to various scenarios of droplet rebound for each of the investigated surface geometry.
{"title":"Droplet bouncing on the surface with micro-structure","authors":"T. Bobinski, G. Sobieraj, M. Psarski, Grzegorz Celichowski, J. Rokicki","doi":"10.24423/AOM.2401","DOIUrl":"https://doi.org/10.24423/AOM.2401","url":null,"abstract":"In this paper, we present static and dynamic interactions of water droplets with a micro-structured surface that exhibits hydrophobic properties. Droplets with two different diameters ( D 0 = 0.6 ± 0.1 mm and D 0 = 2.6 ± 0.1 mm) were studied for impact velocities in the range of 0.1 ÷ 2.5 m/s. This allowed to investigate the influence of gravity on the collision behavior during an impact. The main result of the present research is the determination of the critical conditions for consecutive transitions leading to various scenarios of droplet rebound for each of the investigated surface geometry.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42273377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reflection of elastic waves at the surface of a couple-stress elastic half-space with a viscoelastic support is studied in this paper. Different from the classical elastic solid, there are: a non-dispersive dilatational propagating wave, a dispersive transverse propagating wave and a dispersive evanescent wave in a couple-stress elastic solid. The boundary conditions at the visco-elastically supported surface of a couple-stress elastic half-space include the couple-stress vector and the rotation vector, which disappear in the classical elastic solid. They are used to obtain a set of linear algebraic equation, from which the amplitude ratios of reflection waves with respect to the incident wave can be determined. Then, the reflection coefficients in terms of energy flux ratios are calculated numerically, and the normal energy flux conservation is used to validate the numerical results. At last, the influence of the boundary parameters that reflect the mechanical behavior of a viscoelastic support on the amplitude ratio, the phase shift and the energy partition of reflection waves are discussed based on the numerical results. Both the incident longitudinal displacement wave (the P-wave) and incident transverse displacement wave (the SV-wave) are considered. It is found that the instantaneous elasticity and the delayed viscosity of a viscoelastic support have different influences on the reflection waves.
{"title":"Influences of a visco-elastically supported boundary on reflected waves in a couple-stress elastic half-space","authors":"C. Wang, P. Wei, P. Zhang, Y. Li","doi":"10.24423/AOM.2460","DOIUrl":"https://doi.org/10.24423/AOM.2460","url":null,"abstract":"The reflection of elastic waves at the surface of a couple-stress elastic half-space with a viscoelastic support is studied in this paper. Different from the classical elastic solid, there are: a non-dispersive dilatational propagating wave, a dispersive transverse propagating wave and a dispersive evanescent wave in a couple-stress elastic solid. The boundary conditions at the visco-elastically supported surface of a couple-stress elastic half-space include the couple-stress vector and the rotation vector, which disappear in the classical elastic solid. They are used to obtain a set of linear algebraic equation, from which the amplitude ratios of reflection waves with respect to the incident wave can be determined. Then, the reflection coefficients in terms of energy flux ratios are calculated numerically, and the normal energy flux conservation is used to validate the numerical results. At last, the influence of the boundary parameters that reflect the mechanical behavior of a viscoelastic support on the amplitude ratio, the phase shift and the energy partition of reflection waves are discussed based on the numerical results. Both the incident longitudinal displacement wave (the P-wave) and incident transverse displacement wave (the SV-wave) are considered. It is found that the instantaneous elasticity and the delayed viscosity of a viscoelastic support have different influences on the reflection waves.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45335530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present a new nonlocal elasticity-based analysis method for free vibrations of functionally graded rectangular nanoplates. The introduced method allows taking into account spatial variation of the nonlocal parameter. Governing partial differential equations and associated boundary conditions are derived by employing the variational approach and applying Hamilton’s principle. Displacement field is expressed in a unified way to be able to produce numerical results pertaining to three different plate theories, namely Kirchhoff, Mindlin, and third-order shear deformation theories. The equations are solved numerically by means of the generalized differentia quadrature method. Numerical results are generated by considering simply-supported and cantilever nanoplates undergoing free vibrations. These findings demonstrate the influences of factors such as dimensionless plate length, plate theory, power-law index, and nonlocal parameter ratio upon vibration behavior.
{"title":"Free vibration analysis of functionally graded rectangular nanoplates considering spatial variation of the nonlocal parameter","authors":"A. Ghassabi, S. Dag, E. Cigeroglu","doi":"10.24423/AOM.2414","DOIUrl":"https://doi.org/10.24423/AOM.2414","url":null,"abstract":"We present a new nonlocal elasticity-based analysis method for free vibrations of functionally graded rectangular nanoplates. The introduced method allows taking into account spatial variation of the nonlocal parameter. Governing partial differential equations and associated boundary conditions are derived by employing the variational approach and applying Hamilton’s principle. Displacement field is expressed in a unified way to be able to produce numerical results pertaining to three different plate theories, namely Kirchhoff, Mindlin, and third-order shear deformation theories. The equations are solved numerically by means of the generalized differentia quadrature method. Numerical results are generated by considering simply-supported and cantilever nanoplates undergoing free vibrations. These findings demonstrate the influences of factors such as dimensionless plate length, plate theory, power-law index, and nonlocal parameter ratio upon vibration behavior.","PeriodicalId":8280,"journal":{"name":"Archives of Mechanics","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2017-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44590891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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