Pub Date : 2024-01-09DOI: 10.1016/j.crme.2009.12.00
X. Amandolese, P. Hémon
{"title":"Vortex-induced vibration of a square cylinder in wind tunnel","authors":"X. Amandolese, P. Hémon","doi":"10.1016/j.crme.2009.12.00","DOIUrl":"https://doi.org/10.1016/j.crme.2009.12.00","url":null,"abstract":"","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139442026","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 we obtain an estimate for the increased integrability of the gradient of the solution to the Zaremba problem for divergent elliptic operator in a bounded domain with nontrivial capacity of the Dirichlet boundary conditions. Résumé. Dans cet article, nous obtenons une estimation de l’intégrabilité accrue du gradient de la solution du problème de Zaremba pour un opérateur elliptique divergent dans un domaine borné avec une capacité non triviale des conditions aux limites de Dirichlet. ∗Corresponding author. ISSN (electronic) : 1873-7234 https://comptes-rendus.academie-sciences.fr/mecanique/ 300 Yurij A. Alkhutov and Gregory A. Chechkin
In this paper》(we estimate for the您每年会圣母圣母解决梯度to the Zaremba integrability elliptic运营商In a . for不一bounded domain with the nontrivial容量由Dirichlet边界条件。摘要。在本文中，我们估计了在具有非平凡狄利克雷边界条件的有界域上发散椭圆算子的Zaremba问题解的梯度可积性的增加。∗对应着作者。他的父亲是一名律师，母亲是一名律师，父亲是一名律师，母亲是一名律师。
{"title":"The Meyer’s estimate of solutions to Zaremba problem for second-order elliptic equations in divergent form","authors":"Yu. A. Alkhutov, G. Chechkin","doi":"10.5802/CRMECA.87","DOIUrl":"https://doi.org/10.5802/CRMECA.87","url":null,"abstract":"In this paper we obtain an estimate for the increased integrability of the gradient of the solution to the Zaremba problem for divergent elliptic operator in a bounded domain with nontrivial capacity of the Dirichlet boundary conditions. Résumé. Dans cet article, nous obtenons une estimation de l’intégrabilité accrue du gradient de la solution du problème de Zaremba pour un opérateur elliptique divergent dans un domaine borné avec une capacité non triviale des conditions aux limites de Dirichlet. ∗Corresponding author. ISSN (electronic) : 1873-7234 https://comptes-rendus.academie-sciences.fr/mecanique/ 300 Yurij A. Alkhutov and Gregory A. Chechkin","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78528807","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}
Naima Benmakhlouf, S. Azzouz, L. Hassini, A. Cafsi
An experimental and numerical study of a two-dimensional spatio-temporal variation of the temperature, moisture content, and mechanical stress during the convective drying process of unsaturated and deformable products (leather) were conducted. The bovine leather sample response under convective drying is described by a mathematical model. The leather sample was modeled by an elastic medium, and the mass, heat, and momentum transfer principles are applied. The numerical results agreed well with the corresponding experimental data. The variation of the internal temperature and moisture content was simulated for different drying conditions. A reduction by 15 °C was noted in the optimum temperature for best product quality when the drying air relative humidity was 20%. The cost to achieve a better quality product was found to be minimized due to the decrease in the optimum temperature. The presented simulation results of the elastic material could be applied to the leather, which will reduce the needed time of exposure for predetermined final water content. The damage of the sample is more likely to occur at the beginning of the drying in the time interval of 300–400 s. According to these simulations, the sample’s face, which is exposed to the drying air, has the highest stress; therefore, the sample’s face is at a high risk of cracking. It is also observed that the risk of damage to the sample corresponding to the maximum level of the stress is higher for the highest drying temperature of 60 °C. The peak of the three thicknesses of leather can be achieved for normal stresses in the interval of 60,000 to 140,000 MPa at around 10,000 s.
{"title":"2D model simulating the hydro-rheological behavior of leather during convective drying","authors":"Naima Benmakhlouf, S. Azzouz, L. Hassini, A. Cafsi","doi":"10.5802/CRMECA.86","DOIUrl":"https://doi.org/10.5802/CRMECA.86","url":null,"abstract":"An experimental and numerical study of a two-dimensional spatio-temporal variation of the temperature, moisture content, and mechanical stress during the convective drying process of unsaturated and deformable products (leather) were conducted. The bovine leather sample response under convective drying is described by a mathematical model. The leather sample was modeled by an elastic medium, and the mass, heat, and momentum transfer principles are applied. The numerical results agreed well with the corresponding experimental data. The variation of the internal temperature and moisture content was simulated for different drying conditions. A reduction by 15 °C was noted in the optimum temperature for best product quality when the drying air relative humidity was 20%. The cost to achieve a better quality product was found to be minimized due to the decrease in the optimum temperature. The presented simulation results of the elastic material could be applied to the leather, which will reduce the needed time of exposure for predetermined final water content. The damage of the sample is more likely to occur at the beginning of the drying in the time interval of 300–400 s. According to these simulations, the sample’s face, which is exposed to the drying air, has the highest stress; therefore, the sample’s face is at a high risk of cracking. It is also observed that the risk of damage to the sample corresponding to the maximum level of the stress is higher for the highest drying temperature of 60 °C. The peak of the three thicknesses of leather can be achieved for normal stresses in the interval of 60,000 to 140,000 MPa at around 10,000 s.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82033049","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}
A domain decomposition procedure based on overlapping partitions of the design domain is proposed for solving large problems of smooth topology optimization of plastic continua. The procedure enables the solution of problems with sizes exceeding the available computational and storage capacities. It takes advantage of the favorable features of the integrated limit analysis and design formulation of the smooth topology design problem. The integrated approach preserves the mathematical structure and properties of the underlying static, lower bound problem of limit analysis. In particular, the formulation is characterized by weak coupling between subproblems because it does not involve a stress–strain relationship. The decomposition strategy begins by solving a reduced design problem, using a coarse finite element mesh, followed by an iterative process using a fine discretization. At each iteration, an independent topology optimization subproblem is associated with each subdomain, considered as a substructure. The traction vectors acting on the subdomain boundaries are updated at each iteration as the overlapping partitions are switched. The numerical tests showed that as early as the first iteration, the decomposition process generates a feasible, near optimal design with a weight less than 0.1% above the direct solution.
{"title":"Large-scale smooth plastic topology optimization using domain decomposition","authors":"M. Fourati, Z. Kammoun, J. Néji, H. Smaoui","doi":"10.5802/CRMECA.88","DOIUrl":"https://doi.org/10.5802/CRMECA.88","url":null,"abstract":"A domain decomposition procedure based on overlapping partitions of the design domain is proposed for solving large problems of smooth topology optimization of plastic continua. The procedure enables the solution of problems with sizes exceeding the available computational and storage capacities. It takes advantage of the favorable features of the integrated limit analysis and design formulation of the smooth topology design problem. The integrated approach preserves the mathematical structure and properties of the underlying static, lower bound problem of limit analysis. In particular, the formulation is characterized by weak coupling between subproblems because it does not involve a stress–strain relationship. The decomposition strategy begins by solving a reduced design problem, using a coarse finite element mesh, followed by an iterative process using a fine discretization. At each iteration, an independent topology optimization subproblem is associated with each subdomain, considered as a substructure. The traction vectors acting on the subdomain boundaries are updated at each iteration as the overlapping partitions are switched. The numerical tests showed that as early as the first iteration, the decomposition process generates a feasible, near optimal design with a weight less than 0.1% above the direct solution.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74946457","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}
Ala Eddin Chakroun, A. Hammami, A. De-Juan, F. Chaari, Alfonso Fernández, F. Viadero, M. Haddar
In order to investigate the behaviour of worm drives, a new dynamic model, composed of two blocks, is established and used to extract numerical results. The tooth deflection of the worm drive, bearings, and wheels inertias are taken into consideration. Newmark solving method is applied to solve motion equations. The state of contact of teeth is what enables these signals to manifest themselves. Modal analysis is developed to investigate the different natural modes of the model. Furthermore, modal energetic analysis is used to understand the distribution of strain and kinetic energies. It is also applied to classify natural models into “teeth modes” and “bearing modes”. These two modes constitute two different frequency bands. The dynamic coefficient is measured simultaneously with the gradual increase of the turning speed of the motor. This allows for the evaluation of the overload of the system.
{"title":"Modal energetic analysis and dynamic response of worm gear drives with a new developed dynamic model","authors":"Ala Eddin Chakroun, A. Hammami, A. De-Juan, F. Chaari, Alfonso Fernández, F. Viadero, M. Haddar","doi":"10.5802/CRMECA.80","DOIUrl":"https://doi.org/10.5802/CRMECA.80","url":null,"abstract":"In order to investigate the behaviour of worm drives, a new dynamic model, composed of two blocks, is established and used to extract numerical results. The tooth deflection of the worm drive, bearings, and wheels inertias are taken into consideration. Newmark solving method is applied to solve motion equations. The state of contact of teeth is what enables these signals to manifest themselves. Modal analysis is developed to investigate the different natural modes of the model. Furthermore, modal energetic analysis is used to understand the distribution of strain and kinetic energies. It is also applied to classify natural models into “teeth modes” and “bearing modes”. These two modes constitute two different frequency bands. The dynamic coefficient is measured simultaneously with the gradual increase of the turning speed of the motor. This allows for the evaluation of the overload of the system.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84589376","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 the scientific literature, the study of the impact of the fracture contact area on macro-dispersion in single rough fractures is still an open question. In this work, we study numerically the combined effects of the fracture roughness and the fracture contact area on the non-Fickian transport in single rough fractures. In particular, we quantify the contribution of the fracture contact area on macro-dispersion. These objectives are achieved by estimating the macro-dispersion coefficient from Monte Carlo parallel numerical simulations in pure advection and advection–diffusion cases. When the fractional void SO is equal to 1 (i.e., for σlnb < 0.25), the Monte Carlo simulations show that macro-dispersion results of two contributions, dispersion caused by the heterogeneity of fracture apertures that induces a channelization of flow paths and molecular diffusion, as shown by the analytical solution proposed by Gelhar in 1993. When the fraction void SO is different from 1 (i.e., forσlnb > 0.25), a third mechanism plays in macro-dispersion. The presence of contacts or obstacles causes a disruption of flow paths. This mechanism is identical to that induced by the fracture roughness with a lower amplitude. Its amplitude is the function of the fractional void SO .
{"title":"Impact of the fracture contact area on macro-dispersion in single rough fractures","authors":"A. Beaudoin, M. Farhat","doi":"10.5802/CRMECA.82","DOIUrl":"https://doi.org/10.5802/CRMECA.82","url":null,"abstract":"In the scientific literature, the study of the impact of the fracture contact area on macro-dispersion in single rough fractures is still an open question. In this work, we study numerically the combined effects of the fracture roughness and the fracture contact area on the non-Fickian transport in single rough fractures. In particular, we quantify the contribution of the fracture contact area on macro-dispersion. These objectives are achieved by estimating the macro-dispersion coefficient from Monte Carlo parallel numerical simulations in pure advection and advection–diffusion cases. When the fractional void SO is equal to 1 (i.e., for σlnb < 0.25), the Monte Carlo simulations show that macro-dispersion results of two contributions, dispersion caused by the heterogeneity of fracture apertures that induces a channelization of flow paths and molecular diffusion, as shown by the analytical solution proposed by Gelhar in 1993. When the fraction void SO is different from 1 (i.e., forσlnb > 0.25), a third mechanism plays in macro-dispersion. The presence of contacts or obstacles causes a disruption of flow paths. This mechanism is identical to that induced by the fracture roughness with a lower amplitude. Its amplitude is the function of the fractional void SO .","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78726435","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}
Daniel Resende Gonçalves, Jose dos Reis Vieira de Moura, Paulo Pereira, Marcos Vinícius Agapito Mendes, Henrique Senna Diniz-Pinto
Some nondestructive techniques of the Structural Health Monitoring (SHM) have improved their analysis in the past decades. Among them, the electromechanical impedance-based SHM technique (EMISHM) has been tested in several fields and associated to different statistical methodologies. Considering the nature of the spatial variation of the damage metric data along structures, herein is proposed the use of the indicator kriging method for predicting the existence of a known damage located in the center of an aluminum plate. Maps showing the probability of the damage metric to fall in several value ranges were capable of outlining the areas affected by the damage and predict its location. Comparisons between scenarios with different spacing between PZT patches showed a reduction in the reliability of the model with the increasing of such spacing. Also, for the structure under study, it demonstrates that it is not possible to obtain results by the methodology for distance between sensors/actuators greater than 16.67 cm. However, the results show that this approach can be a viable alternative for using damage metrics to map regions affected by damage and its location.
{"title":"Indicator kriging for damage position prediction by the use of electromechanical impedance-based structural health monitoring","authors":"Daniel Resende Gonçalves, Jose dos Reis Vieira de Moura, Paulo Pereira, Marcos Vinícius Agapito Mendes, Henrique Senna Diniz-Pinto","doi":"10.5802/CRMECA.81","DOIUrl":"https://doi.org/10.5802/CRMECA.81","url":null,"abstract":"Some nondestructive techniques of the Structural Health Monitoring (SHM) have improved their analysis in the past decades. Among them, the electromechanical impedance-based SHM technique (EMISHM) has been tested in several fields and associated to different statistical methodologies. Considering the nature of the spatial variation of the damage metric data along structures, herein is proposed the use of the indicator kriging method for predicting the existence of a known damage located in the center of an aluminum plate. Maps showing the probability of the damage metric to fall in several value ranges were capable of outlining the areas affected by the damage and predict its location. Comparisons between scenarios with different spacing between PZT patches showed a reduction in the reliability of the model with the increasing of such spacing. Also, for the structure under study, it demonstrates that it is not possible to obtain results by the methodology for distance between sensors/actuators greater than 16.67 cm. However, the results show that this approach can be a viable alternative for using damage metrics to map regions affected by damage and its location.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82001062","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 work, the computational fluid dynamics technique is employed to study operating condition effects on the optimum value of an important parameter called the nozzle exit position (NXP) for an ejector design. This ejector uses the gas R134a as the working fluid. Numerical tests are carried out using a combination of the REFPROP 7.0 database state equation and the high-Reynolds version of the SST k–ω model. Good agreement in terms of entrainment ratio and critical temperature is obtained between computed values and measurements. In addition, numerical results indicate that the optimum NXP maximizes ejector performance and is highly dependent on operating conditions.
本文采用计算流体力学方法研究了工况对喷射器出口位置(NXP)最优值的影响。该喷射器使用气体R134a作为工作流体。采用REFPROP 7.0数据库状态方程和高雷诺数版本的SST k -ω模型进行了数值试验。在夹带比和临界温度方面，计算值与测量值很好地吻合。此外，数值结果表明，最优的NXP使喷射器性能最大化，并且高度依赖于操作条件。
{"title":"CFD analysis of operating condition effects on optimum nozzle exit position of a supersonic ejector using the refrigerant R134a","authors":"A. Hadj, M. Boulenouar","doi":"10.5802/crmeca.60","DOIUrl":"https://doi.org/10.5802/crmeca.60","url":null,"abstract":"In this work, the computational fluid dynamics technique is employed to study operating condition effects on the optimum value of an important parameter called the nozzle exit position (NXP) for an ejector design. This ejector uses the gas R134a as the working fluid. Numerical tests are carried out using a combination of the REFPROP 7.0 database state equation and the high-Reynolds version of the SST k–ω model. Good agreement in terms of entrainment ratio and critical temperature is obtained between computed values and measurements. In addition, numerical results indicate that the optimum NXP maximizes ejector performance and is highly dependent on operating conditions.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76376955","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}
Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate materials and mechanical properties. An analytical approach has been developed in this paper to accurately predict toroidal vibrations of an elastic nanosphere in water–glycerol mixture. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. The influence of key parameters such as glycerol mass fraction, sphere radius, and angular mode number are studied. We demonstrate that the sphere radius plays a significant role on the quality factor. Results also highlight three behavior zones: viscous fluid, transition, and elastic solid. In addition, these investigations can serve as benchmark solution in design of liquid sensors.
{"title":"Correlation between the toroidal modes of an elastic sphere and the viscosity of liquids","authors":"J. L. Pommellec, A. E. Baroudi","doi":"10.5802/CRMECA.79","DOIUrl":"https://doi.org/10.5802/CRMECA.79","url":null,"abstract":"Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate materials and mechanical properties. An analytical approach has been developed in this paper to accurately predict toroidal vibrations of an elastic nanosphere in water–glycerol mixture. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. The influence of key parameters such as glycerol mass fraction, sphere radius, and angular mode number are studied. We demonstrate that the sphere radius plays a significant role on the quality factor. Results also highlight three behavior zones: viscous fluid, transition, and elastic solid. In addition, these investigations can serve as benchmark solution in design of liquid sensors.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86395639","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 original state-dependent fractional stress-dilatancy (FSD) equation for soils is developed based on the critical state lines (CSLs) with linear form. However, experimental evidences showed that the CSLs of soil in the p ′–q and e–p ′ planes could be both nonlinear as well due to significant material degradation. This note aims to propose a unified FSD equation for soils with arbitrary types of CSLs. Detailed derivations are provided. To validate the proposed FSD equation, a series of triaxial test results of ballast and rockfill are simulated.
{"title":"Fractional stress-dilatancy equation based on critical state lines with arbitrary form","authors":"Yifei Sun, Jiancheng Zhang","doi":"10.5802/CRMECA.78","DOIUrl":"https://doi.org/10.5802/CRMECA.78","url":null,"abstract":"The original state-dependent fractional stress-dilatancy (FSD) equation for soils is developed based on the critical state lines (CSLs) with linear form. However, experimental evidences showed that the CSLs of soil in the p ′–q and e–p ′ planes could be both nonlinear as well due to significant material degradation. This note aims to propose a unified FSD equation for soils with arbitrary types of CSLs. Detailed derivations are provided. To validate the proposed FSD equation, a series of triaxial test results of ballast and rockfill are simulated.","PeriodicalId":50997,"journal":{"name":"Comptes Rendus Mecanique","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84444502","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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