A preliminary numerical simulation of the microscopic two-phase fluid motion on a solid surface was conducted using an interface-tracking method based on the phase-field model (PFM). Two variations of the lattice Boltzmann method (LBM) based on fictitious particle kinematics are proposed for solving diffuse-interface advection equations which were revised to improve volume-of-fluid conservation in the PFM simulations. The major findings are as follows: (1) the interface-tracking method accurately predicted the capillary force effect on dynamic two-phase fluid systems with a high density ratio between parallel plates; (2) the initial shape and volume of the two-phase fluid were retained adequately in linear translation with the use of the LBMs. These results proved that the PFM-based method and the LBM-based advection schemes can be used for simulating two-phase fluid motions in various macroand microfluidics problems for devices, machineries and higher-throughput microdevice fabrication processes.
{"title":"Phase-Field Model-Based Simulation of Motions of a Two-Phase Fluid on Solid Surface","authors":"N. Takada, J. Matsumoto, S. Matsumoto","doi":"10.1299/JCST.7.322","DOIUrl":"https://doi.org/10.1299/JCST.7.322","url":null,"abstract":"A preliminary numerical simulation of the microscopic two-phase fluid motion on a solid surface was conducted using an interface-tracking method based on the phase-field model (PFM). Two variations of the lattice Boltzmann method (LBM) based on fictitious particle kinematics are proposed for solving diffuse-interface advection equations which were revised to improve volume-of-fluid conservation in the PFM simulations. The major findings are as follows: (1) the interface-tracking method accurately predicted the capillary force effect on dynamic two-phase fluid systems with a high density ratio between parallel plates; (2) the initial shape and volume of the two-phase fluid were retained adequately in linear translation with the use of the LBMs. These results proved that the PFM-based method and the LBM-based advection schemes can be used for simulating two-phase fluid motions in various macroand microfluidics problems for devices, machineries and higher-throughput microdevice fabrication processes.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116263735","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}
A new method of Adaptive Plan system with Genetic Algorithm called APGA is proposed to reduce a large amount of calculation cost and to improve a stability in convergence to an optimal solution for multi-peak optimization problems with multidimensions. This is an approach that combines the global search ability of Genetic Algorithm (GA) and the local search ability of Adaptive Plan (AP). The APGA differs from GAs in handling design variable vectors (DVs). GAs generally encode DVs into genes and handle them through GA operators. However, the APGA encodes control variable vectors (CVs) of AP, which searches for local optimum, into its genes. CVs determine the global behavior of AP, and DVs are handled by AP in the optimization process of APGA. In this paper, we introduce some strategies using APGA to solve a huge scale of optimization problem and to improve the convergence towards the optimal solution. These methodologies are applied to several benchmark functions with multi-dimensions to evaluate its performance. We confirmed satisfactory performance through various benchmark tests.
{"title":"Evolutionary Strategies of Adaptive Plan System with Genetic Algorithm","authors":"Hieu Pham, Sousuke Tooyama, H. Hasegawa","doi":"10.1299/JCST.6.129","DOIUrl":"https://doi.org/10.1299/JCST.6.129","url":null,"abstract":"A new method of Adaptive Plan system with Genetic Algorithm called APGA is proposed to reduce a large amount of calculation cost and to improve a stability in convergence to an optimal solution for multi-peak optimization problems with multidimensions. This is an approach that combines the global search ability of Genetic Algorithm (GA) and the local search ability of Adaptive Plan (AP). The APGA differs from GAs in handling design variable vectors (DVs). GAs generally encode DVs into genes and handle them through GA operators. However, the APGA encodes control variable vectors (CVs) of AP, which searches for local optimum, into its genes. CVs determine the global behavior of AP, and DVs are handled by AP in the optimization process of APGA. In this paper, we introduce some strategies using APGA to solve a huge scale of optimization problem and to improve the convergence towards the optimal solution. These methodologies are applied to several benchmark functions with multi-dimensions to evaluate its performance. We confirmed satisfactory performance through various benchmark tests.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114964988","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}
In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at speeds upwards of 41.7m/s (150km/hr). If a ball at this speed hits the batter, serious injury can occur. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/ LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fastball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of the injury which can be applied in actual baseball games are also discussed.
{"title":"Study on Impact Loading and Humerus Injury for Baseball","authors":"Shinobu Sakai, J. Oda, S. Yonemura, J. Sakamoto","doi":"10.1299/JCST.2.609","DOIUrl":"https://doi.org/10.1299/JCST.2.609","url":null,"abstract":"In the United States and Japan, baseball is a very popular sport played by many people. However, the ball used is hard and moves fast. A professional baseball pitcher in good form can throw a ball at speeds upwards of 41.7m/s (150km/hr). If a ball at this speed hits the batter, serious injury can occur. In this paper we will describe our investigations on the impact of a baseball with living tissues by finite element analysis. Baseballs were projected at a load cell plate using a specialized pitching machine. The dynamic properties of the baseball were determined by comparing the wall-ball collision experimentally measuring the time history of the force and the displacement using dynamic finite element analysis software (ANSYS/ LS-DYNA). The finite element model representing a human humerus and its surrounding tissue was simulated for balls pitched at variable speeds and pitch types (knuckle and fastball). In so doing, the stress distribution and stress wave in the bone and soft tissue were obtained. From the results, the peak stress of the bone nearly yielded to the stress caused by a high fast ball. If the collision position or direction is moved from the center of the upper arm, it is assumed that the stress exuded on the humerus will be reduced. Some methods to reduce the severity of the injury which can be applied in actual baseball games are also discussed.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126372532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes a systematic scheme of removing void elements to achieve fast and efficient level set based topology optimization. When performing optimization, unless special treatment is applied to the stiffness matrix, the density of these void elements are usually represented numerically by a small positive value. In level set based topology optimization, since the amount of computational resources required for FEM dwarfs those required for level set evolution, the removal of these elements from the global stiffness matrix can drastically reduce total computation time. The proposed scheme removes the void elements, determined by their nodes' level set values, from the optimization process by use of mapping procedures. The results presented here show time reductions of at least 70%. An additional advantage of the presented scheme is that it can be easily used with any black box FEM routine.
{"title":"Removing Void Elements for Structural Level Set Topology Optimizaiton","authors":"Chen Jian Ken Lee, Zhiqiang Zhang, N. Takano","doi":"10.1299/JCST.3.385","DOIUrl":"https://doi.org/10.1299/JCST.3.385","url":null,"abstract":"This paper proposes a systematic scheme of removing void elements to achieve fast and efficient level set based topology optimization. When performing optimization, unless special treatment is applied to the stiffness matrix, the density of these void elements are usually represented numerically by a small positive value. In level set based topology optimization, since the amount of computational resources required for FEM dwarfs those required for level set evolution, the removal of these elements from the global stiffness matrix can drastically reduce total computation time. The proposed scheme removes the void elements, determined by their nodes' level set values, from the optimization process by use of mapping procedures. The results presented here show time reductions of at least 70%. An additional advantage of the presented scheme is that it can be easily used with any black box FEM routine.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125933747","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}
In the previous paper, the geometrically necessary (GN) incompatibility is newly defined and a new annihilation term of dislocation pairs due to the dynamic recovery is introduced into an expression of dislocation density. Furthermore, a multiscale model of crystal plasticity is proposed by considering the GN dislocation density and incompatibility. However, details of dislocation-crystal plasticity calculation are not given. In this paper, we explain a method of dislocation-crystal plasticity analysis. A finite element simulation is carried out for an f.c.c. single crystal under plane strain tension. It is numerically predicted that micro shear bands are formed at large strain, and sub-GNBs: small angle tilt boundaries are induced along these bands. Furthermore, the annihilation of dislocation pairs and the increase of dislocation mean free path characterizing stage III of work-hardening are computationally predicted.
{"title":"A Dislocation-Crystal Plasticity Simulation on FCC Single Crystal Considering Geometrically Necessary Dislocation Density and Incompatibility","authors":"Y. Aoyagi, K. Shizawa","doi":"10.1299/JCST.2.197","DOIUrl":"https://doi.org/10.1299/JCST.2.197","url":null,"abstract":"In the previous paper, the geometrically necessary (GN) incompatibility is newly defined and a new annihilation term of dislocation pairs due to the dynamic recovery is introduced into an expression of dislocation density. Furthermore, a multiscale model of crystal plasticity is proposed by considering the GN dislocation density and incompatibility. However, details of dislocation-crystal plasticity calculation are not given. In this paper, we explain a method of dislocation-crystal plasticity analysis. A finite element simulation is carried out for an f.c.c. single crystal under plane strain tension. It is numerically predicted that micro shear bands are formed at large strain, and sub-GNBs: small angle tilt boundaries are induced along these bands. Furthermore, the annihilation of dislocation pairs and the increase of dislocation mean free path characterizing stage III of work-hardening are computationally predicted.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128431325","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}
In this study, the circumferential strain concentrations in cylindrical and square tubes with corrugated surfaces subjected to axial compression are studied using the finite element method. In cylindrical tubes, the yield strength σy, the hardening coefficient Eh of the material and the thickness t of the tube wall exert only a small influence on the strain concentration, so that the maximum circumferential strain can be approximately evaluated as a function of the wavelength 2λ and the amplitude a of the corrugations, and the cylinder radius R. For square tubes, however, the effect of the corner radius r, the thickness t, the yield strength σy, and the hardening coefficient Eh on the strain concentration is comparable to that of the wavelength 2λ and the amplitude a of the corrugations. The maximum circumferential strain increases with a decrease in the corner radius r/D, with a decrease in the thickness t, and with an increase in the ratio σy/Eh.
{"title":"Circumferential Strain Concentration of Corrugated Tubes Subjected to Axial Collapse","authors":"Dai-heng Chen, S. Ozaki","doi":"10.1299/JCST.2.632","DOIUrl":"https://doi.org/10.1299/JCST.2.632","url":null,"abstract":"In this study, the circumferential strain concentrations in cylindrical and square tubes with corrugated surfaces subjected to axial compression are studied using the finite element method. In cylindrical tubes, the yield strength σy, the hardening coefficient Eh of the material and the thickness t of the tube wall exert only a small influence on the strain concentration, so that the maximum circumferential strain can be approximately evaluated as a function of the wavelength 2λ and the amplitude a of the corrugations, and the cylinder radius R. For square tubes, however, the effect of the corner radius r, the thickness t, the yield strength σy, and the hardening coefficient Eh on the strain concentration is comparable to that of the wavelength 2λ and the amplitude a of the corrugations. The maximum circumferential strain increases with a decrease in the corner radius r/D, with a decrease in the thickness t, and with an increase in the ratio σy/Eh.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124794006","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}
A. Tani, Kenji Tanaka, Yuichiro Yamabe, H. Kawamura
The authors have already proposed an intelligent fuzzy optimal and active control system (IFOACS) and the effectiveness of IFOACS was proved using digital simulations and shaking table tests. However, the results show that the control effect of IFOACS becomes small in case of near-source region earthquakes. To improve control effects in case of near-source region earthquakes, a combinatorial control system (CCS), in which IFOACS is combined with a fuzzy active control system (FACS), is also proposed. In this paper, control rules in CCS are optimized using parameter-free genetic algorithms (PfGAs) considering limitations of an actuator such as maximal strokes and control forces. Effectiveness of proposed combinatorial control system (CCS) is verified and discussed based on results of digital simulations.
{"title":"Intelligent Fuzzy Optimal Active and Combinatorial Control System of Building Structures","authors":"A. Tani, Kenji Tanaka, Yuichiro Yamabe, H. Kawamura","doi":"10.1299/JCST.2.381","DOIUrl":"https://doi.org/10.1299/JCST.2.381","url":null,"abstract":"The authors have already proposed an intelligent fuzzy optimal and active control system (IFOACS) and the effectiveness of IFOACS was proved using digital simulations and shaking table tests. However, the results show that the control effect of IFOACS becomes small in case of near-source region earthquakes. To improve control effects in case of near-source region earthquakes, a combinatorial control system (CCS), in which IFOACS is combined with a fuzzy active control system (FACS), is also proposed. In this paper, control rules in CCS are optimized using parameter-free genetic algorithms (PfGAs) considering limitations of an actuator such as maximal strokes and control forces. Effectiveness of proposed combinatorial control system (CCS) is verified and discussed based on results of digital simulations.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128663247","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}
With the rapid growth of the WAN infrastructures and enhancement of MPI libraries for WAN environment, Grid computing is expected to be a practical methodology for performing very large finite element analyses. In particular, the utilization of Grid enhanced MPI libraries allows one to execute legacy programs on WAN environments, which is very attractive for finite element application users. However, the high communication cost associated with WANs has discouraged its use as a parallel environment for finite element analysis. In this study, we focus on the utilization of Grid environments, in particular on cluster-of-clusters environments for the execution of FEA, and propose a hierarchical communication pattern to reduce the communication cost. By analytically estimating the communication cost, based on the decomposed FE mesh, we assess the effectiveness of the hierarchical communication pattern. We then show the obtained communication cost reduction by numerical experiments performed on cluster-of-clusters on WAN.
{"title":"Communication Cost Reduction by Hierarchical Communication Pattern for FE Computation on Cluster-of-Clusters","authors":"Masae Hayashi, H. Okuda","doi":"10.1299/JCST.4.136","DOIUrl":"https://doi.org/10.1299/JCST.4.136","url":null,"abstract":"With the rapid growth of the WAN infrastructures and enhancement of MPI libraries for WAN environment, Grid computing is expected to be a practical methodology for performing very large finite element analyses. In particular, the utilization of Grid enhanced MPI libraries allows one to execute legacy programs on WAN environments, which is very attractive for finite element application users. However, the high communication cost associated with WANs has discouraged its use as a parallel environment for finite element analysis. In this study, we focus on the utilization of Grid environments, in particular on cluster-of-clusters environments for the execution of FEA, and propose a hierarchical communication pattern to reduce the communication cost. By analytically estimating the communication cost, based on the decomposed FE mesh, we assess the effectiveness of the hierarchical communication pattern. We then show the obtained communication cost reduction by numerical experiments performed on cluster-of-clusters on WAN.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120895317","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}
Recent earth environment problem is accelerating rapid popularization of hybrid or electric vehicles replacing conventional vehicles powered by fossil fuels. The electric vehicles don’t need exhaust pipes and power train system like propeller shaft under the floor, so their floors can be flattened. Flat floor may also contribute to crash safety and suitable structural material for this purpose will be required. In this paper, authors studied optimal shape to improve energy absorption ability of truss core panel which the usage is considered as vehicle structure. Effective optimization technique especially for nonlinear problem, Radial Basis Function (RBF) network with Response Surface Method (RSM) is adopted in the paper and applied to optimize the shape of truss core panel. Energy absorption quantities for x, y, and z directions were treated as independent objectives and multi-objective optimization was performed. A commercial preprocessor HyperMorph is used for morphing, explicit FEM software LS-DYNA is used to solve crash analysis and LS-OPT is used to handle multiple jobs and optimization process. As the result, 7.1 % of improvement for the energy absorption for the crash in x direction was achieved and Pareto curves for the objectives were obtained.
{"title":"Shape Optimization to Improve Impact Energy Absorption Ability of Truss Core Panel","authors":"Sunao Tokura, I. Hagiwara","doi":"10.1299/JCST.5.1","DOIUrl":"https://doi.org/10.1299/JCST.5.1","url":null,"abstract":"Recent earth environment problem is accelerating rapid popularization of hybrid or electric vehicles replacing conventional vehicles powered by fossil fuels. The electric vehicles don’t need exhaust pipes and power train system like propeller shaft under the floor, so their floors can be flattened. Flat floor may also contribute to crash safety and suitable structural material for this purpose will be required. In this paper, authors studied optimal shape to improve energy absorption ability of truss core panel which the usage is considered as vehicle structure. Effective optimization technique especially for nonlinear problem, Radial Basis Function (RBF) network with Response Surface Method (RSM) is adopted in the paper and applied to optimize the shape of truss core panel. Energy absorption quantities for x, y, and z directions were treated as independent objectives and multi-objective optimization was performed. A commercial preprocessor HyperMorph is used for morphing, explicit FEM software LS-DYNA is used to solve crash analysis and LS-OPT is used to handle multiple jobs and optimization process. As the result, 7.1 % of improvement for the energy absorption for the crash in x direction was achieved and Pareto curves for the objectives were obtained.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116453438","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}
In this paper, nonlinear boundary value problems are analyzed by using the over-range collocation method (ORCM). By introducing some collocation points, which are located at outside of domain of the analyzed body, unsatisfactory issue of the positivity conditions of boundary points in collocation methods can be avoided. Quite accurate numerical results of the nonlinear partial differential equations have been obtained. Because the ORCM does not demand any specific type of partial differential equations, it shows promise of wide engineering applications of the ORCM.
{"title":"Nonlinear Analyses by Using the ORCM","authors":"Yong-Ming Guo, Hirotaka Osako, S. Kamitani","doi":"10.1299/JCST.7.114","DOIUrl":"https://doi.org/10.1299/JCST.7.114","url":null,"abstract":"In this paper, nonlinear boundary value problems are analyzed by using the over-range collocation method (ORCM). By introducing some collocation points, which are located at outside of domain of the analyzed body, unsatisfactory issue of the positivity conditions of boundary points in collocation methods can be avoided. Quite accurate numerical results of the nonlinear partial differential equations have been obtained. Because the ORCM does not demand any specific type of partial differential equations, it shows promise of wide engineering applications of the ORCM.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126897119","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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