A new theoretical model of axial crushing of cylindrical tubes with corrugated surfaces has been developed in which the crushing force is analyzed by considering the equilibrium of work done by the crushing force and the energy required to deform the tube. The energy absorbed by the cylindrical tube being crushed is taken to be the sum of the bending energy term and the membrane energy term, which results from compression or extension of a tube wall in the radial direction. The analysis results of the model predict two different modes, termed P- and S-modes, may occur in the collapse of cylindrical tubes with corrugated surfaces. In the P-mode, the compressive force oscillates with folding one after another, whereas in the S-mode the compressive force increases monotonically. Both the mode classification charts and the average crushing force predicted by the developed model are found to be in good agreement with FEM numerical calculation results. In addition, it is found that the increase in the compressive force load for the S-mode is principally due to an increase in the bending energy with deformation.
{"title":"Theoretical Analysis of Axial Crushing of Cylindrical Tubes with Corrugated Surfaces","authors":"Dai-heng Chen, S. Ozaki","doi":"10.1299/JCST.3.327","DOIUrl":"https://doi.org/10.1299/JCST.3.327","url":null,"abstract":"A new theoretical model of axial crushing of cylindrical tubes with corrugated surfaces has been developed in which the crushing force is analyzed by considering the equilibrium of work done by the crushing force and the energy required to deform the tube. The energy absorbed by the cylindrical tube being crushed is taken to be the sum of the bending energy term and the membrane energy term, which results from compression or extension of a tube wall in the radial direction. The analysis results of the model predict two different modes, termed P- and S-modes, may occur in the collapse of cylindrical tubes with corrugated surfaces. In the P-mode, the compressive force oscillates with folding one after another, whereas in the S-mode the compressive force increases monotonically. Both the mode classification charts and the average crushing force predicted by the developed model are found to be in good agreement with FEM numerical calculation results. In addition, it is found that the increase in the compressive force load for the S-mode is principally due to an increase in the bending energy with deformation.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"35 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":"114515185","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}
Masahiro Yamamoto, A. Fujinami, S. Ogata, Y. Shibutani
Innovative thin film technology to realize the finer electric devices needs to understand the atomic level process of film growth and its relationship to the film characterization. In this paper, the long film growth phenomena for a few micro-second order with the short severe collisions by incident particles are analyzed by the proposed hybridized atomistic modeling. This method combined molecular dynamics (MD) with kinetic Monte Carlo (KMC) can directly treat two types of events of deposition and diffusion, which have quite different time scales. The solutions suggest that the large incident kinetic energy of deposited atoms compatible to the realistic physical vapor deposition (PVD) impels to fluctuate the equilibrium on Al (111) surface very drastically and affects the atomic level surface morphology. It is found that the faster incident atoms with 1.0 × 104 m/s can make the smoother surface than those with the velocity of 1.0 × 103 m/s. This is due to much activated atomic migration, which can be realized only by MD.
{"title":"Hybridized Atomistic Modeling of Migration Observed on Thin Film Surface by Incident Particles","authors":"Masahiro Yamamoto, A. Fujinami, S. Ogata, Y. Shibutani","doi":"10.1299/JCST.1.14","DOIUrl":"https://doi.org/10.1299/JCST.1.14","url":null,"abstract":"Innovative thin film technology to realize the finer electric devices needs to understand the atomic level process of film growth and its relationship to the film characterization. In this paper, the long film growth phenomena for a few micro-second order with the short severe collisions by incident particles are analyzed by the proposed hybridized atomistic modeling. This method combined molecular dynamics (MD) with kinetic Monte Carlo (KMC) can directly treat two types of events of deposition and diffusion, which have quite different time scales. The solutions suggest that the large incident kinetic energy of deposited atoms compatible to the realistic physical vapor deposition (PVD) impels to fluctuate the equilibrium on Al (111) surface very drastically and affects the atomic level surface morphology. It is found that the faster incident atoms with 1.0 × 104 m/s can make the smoother surface than those with the velocity of 1.0 × 103 m/s. This is due to much activated atomic migration, which can be realized only by MD.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"92 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":"128392033","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}
Performance maps, which represent relations between performance and geometry parameters, are essential for engineers to make a first decision on preliminary specification of a product to be designed. However, actual design often needs to consider various performance and geometry parameters simultaneously. Therefore, the resulting performance maps must be constructed in a high-dimensional form. Based on these requirements, this paper proposes and demonstrates performance map construction with the aid of data mining techniques. Data mining can reveal characteristic patterns in high-dimensional data with performance and geometry parameters. Therefore, the data mining results make it easy to interpret complex features of performance vs. geometry relations, and help engineers to discover new knowledge for engineering design through interpretation. The present demonstration of a centrifugal diffuser demonstrated that the data mining techniques are suitable and applicable to high-dimensional performance map construction, together with actual acquisition of new knowledge for diffuser design that was unknown from conventional quasi-one-dimensional nozzle theory.
{"title":"Performance Map Construction for a Centrifugal Diffuser with Data Mining Techniques","authors":"K. Shimoyama, K. Sugimura, S. Jeong, S. Obayashi","doi":"10.1299/JCST.4.36","DOIUrl":"https://doi.org/10.1299/JCST.4.36","url":null,"abstract":"Performance maps, which represent relations between performance and geometry parameters, are essential for engineers to make a first decision on preliminary specification of a product to be designed. However, actual design often needs to consider various performance and geometry parameters simultaneously. Therefore, the resulting performance maps must be constructed in a high-dimensional form. Based on these requirements, this paper proposes and demonstrates performance map construction with the aid of data mining techniques. Data mining can reveal characteristic patterns in high-dimensional data with performance and geometry parameters. Therefore, the data mining results make it easy to interpret complex features of performance vs. geometry relations, and help engineers to discover new knowledge for engineering design through interpretation. The present demonstration of a centrifugal diffuser demonstrated that the data mining techniques are suitable and applicable to high-dimensional performance map construction, together with actual acquisition of new knowledge for diffuser design that was unknown from conventional quasi-one-dimensional nozzle theory.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"15 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":"130105533","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 WAN infrastructures and development of Grid middleware, the cluster-of-clusters has become a realistic methodology for executing computationdemanding applications. While distributed computing or loosely connected applications have been successfully ported to the Grid environment, few tightly connected applications such as parallel finite element analysis (FEA) have been attempted. In this paper we focus on an iterative solver which is often used in FEA: the conjugate gradient (CG) method. By using both predictions and numerical experiments we evaluate the performance of the CG method parallelized via domain decomposition. From numerical experiments we measure the inter-cluster execution time and find it to be close to that obtained by the slowest cluster. At the level of performance currently found in most WAN systems, as long as the number of processes is kept adequately small, the increase in communication cost due to WAN is small relative to the computation cost. For a very large test model which realistically requires the utilization of remote resources, the work ratio stays above 86% even for 64 processes. Especially for very large models, using the distributed environment is expected to be a practical methodology even for parallel computations with communication as frequent as the one found in FEA. To evaluate the feasibility of parallel FEA on the C-of-C, we have proposed methods for a priori finding the optimal number of processes.
{"title":"Feasibility Study and Predictability on the Performance of Parallel FEM Using Clusters on WAN","authors":"Masae Muraoka, H. Okuda","doi":"10.1299/JCST.3.460","DOIUrl":"https://doi.org/10.1299/JCST.3.460","url":null,"abstract":"With the rapid growth of WAN infrastructures and development of Grid middleware, the cluster-of-clusters has become a realistic methodology for executing computationdemanding applications. While distributed computing or loosely connected applications have been successfully ported to the Grid environment, few tightly connected applications such as parallel finite element analysis (FEA) have been attempted. In this paper we focus on an iterative solver which is often used in FEA: the conjugate gradient (CG) method. By using both predictions and numerical experiments we evaluate the performance of the CG method parallelized via domain decomposition. From numerical experiments we measure the inter-cluster execution time and find it to be close to that obtained by the slowest cluster. At the level of performance currently found in most WAN systems, as long as the number of processes is kept adequately small, the increase in communication cost due to WAN is small relative to the computation cost. For a very large test model which realistically requires the utilization of remote resources, the work ratio stays above 86% even for 64 processes. Especially for very large models, using the distributed environment is expected to be a practical methodology even for parallel computations with communication as frequent as the one found in FEA. To evaluate the feasibility of parallel FEA on the C-of-C, we have proposed methods for a priori finding the optimal number of processes.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"13 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":"127026833","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}
One of the cavitation models for cavitating flow simulations is the bubble dynamics based method (bubble model). In a typical bubble dynamics based method, the Rayleigh–Plesset equation is solved for determining the volumetric motion of a bubble. It is derived for a single bubble in uniform fluid, and thus, is not adequate for a bubble in high void fraction fluid. Therefore, in the existing bubble dynamics based model, high void fraction fluid has not been treated as far as utilizing the Rayleigh–Plesset equation is concerned. In this paper, a bubble dynamics model treating high void fraction region is proposed. The present model has a threshold between low and high void fraction. Below the threshold, Rayleigh–Plesset equation is solved. Above the threshold, the second derivative of temporal difference of a bubble radius is set to be zero when the bubble is expanding, and Rayleigh–Plesset equation is again solved when the bubble is shrinking. For computational example, flow around Clark-Y11.7% and NACA0015 is calculated for validation of this approach and compared with experiment and the old bubble dynamics based method.
{"title":"Improvement of Bubble Model in High Void Fraction for Cavitating Flow Simulations","authors":"N. Tsurumi, Y. Tamura, Y. Matsumoto","doi":"10.1299/JCST.6.113","DOIUrl":"https://doi.org/10.1299/JCST.6.113","url":null,"abstract":"One of the cavitation models for cavitating flow simulations is the bubble dynamics based method (bubble model). In a typical bubble dynamics based method, the Rayleigh–Plesset equation is solved for determining the volumetric motion of a bubble. It is derived for a single bubble in uniform fluid, and thus, is not adequate for a bubble in high void fraction fluid. Therefore, in the existing bubble dynamics based model, high void fraction fluid has not been treated as far as utilizing the Rayleigh–Plesset equation is concerned. In this paper, a bubble dynamics model treating high void fraction region is proposed. The present model has a threshold between low and high void fraction. Below the threshold, Rayleigh–Plesset equation is solved. Above the threshold, the second derivative of temporal difference of a bubble radius is set to be zero when the bubble is expanding, and Rayleigh–Plesset equation is again solved when the bubble is shrinking. For computational example, flow around Clark-Y11.7% and NACA0015 is calculated for validation of this approach and compared with experiment and the old bubble dynamics based method.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"67 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":"123850778","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, stress intensity factors for a three dimensional rectangular interfacial crack are considered on the idea of the body force method. In the numerical calculations, unknown body force densities are approximated by the products of the fundamental densities and power series; here the fundamental densities are chosen to express singular stress fields due to an interface crack exactly. The calculation shows that the present method gives rapidly converging numerical solutions and highly satisfied boundary conditions. The stress intensity factors for a rectangular interface crack are indicated accurately with varying the aspect ratio, and biomaterial parameter.
{"title":"Stress Intensity Factor for a Rectangular Interface Crack in Three Dimensional Bimaterials","authors":"N. Noda, Chun-hui Xu, Y. Takase","doi":"10.1299/JCST.3.224","DOIUrl":"https://doi.org/10.1299/JCST.3.224","url":null,"abstract":"In this paper, stress intensity factors for a three dimensional rectangular interfacial crack are considered on the idea of the body force method. In the numerical calculations, unknown body force densities are approximated by the products of the fundamental densities and power series; here the fundamental densities are chosen to express singular stress fields due to an interface crack exactly. The calculation shows that the present method gives rapidly converging numerical solutions and highly satisfied boundary conditions. The stress intensity factors for a rectangular interface crack are indicated accurately with varying the aspect ratio, and biomaterial parameter.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"46 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":"123993846","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}
Qin-yin Fan, C. Guo, T. Takagi, Kikuo Narumiya, H. Hattori
At the initial stage of injection, the injection flow has not yet broken up and in a range of small atmosphere pressure (16∼500KPa), the tip of the injection flow always forms a shape of mushroom. [1] [2] Moreover, the umbrella of the mushroom is always very big and its root is always very thin, especially when the atmosphere pressure is relatively low (88KPa, or 100mmHg). These phenomena are not known popularly and the reason of mushroom formation is not clear. In this paper, with the MARS method for simulating free surface, analysis of injection flow is practiced. The phenomena are reproduced and the reason is cleared that the formation of the mushroom is induced by the momentum exchange between the injection fuel flow with very high speed and the very complex flow of the air.
{"title":"Numerical Simulation of Atomization in Nozzle Injection Flow","authors":"Qin-yin Fan, C. Guo, T. Takagi, Kikuo Narumiya, H. Hattori","doi":"10.1299/JCST.2.295","DOIUrl":"https://doi.org/10.1299/JCST.2.295","url":null,"abstract":"At the initial stage of injection, the injection flow has not yet broken up and in a range of small atmosphere pressure (16∼500KPa), the tip of the injection flow always forms a shape of mushroom. [1] [2] Moreover, the umbrella of the mushroom is always very big and its root is always very thin, especially when the atmosphere pressure is relatively low (88KPa, or 100mmHg). These phenomena are not known popularly and the reason of mushroom formation is not clear. In this paper, with the MARS method for simulating free surface, analysis of injection flow is practiced. The phenomena are reproduced and the reason is cleared that the formation of the mushroom is induced by the momentum exchange between the injection fuel flow with very high speed and the very complex flow of the air.","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":"114716722","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}
The effect of compressive or tensile plane-stress on formation energies and electronic properties of point defects in Si single crystal was studied by first principles approach for in-plane strain up to 5.0 %. It was found that the formation energy of interstitial Si (I) decreased under tensile in-plane strain. On the other hand, the formation energy of vacancy (V) decreased under compressive in-plane strain. The most stable states of I and V in intrinsic Si were I+2 at T site and V0 respectively, independent of type and value of the in-plane strain.
{"title":"Ab Initio Analysis of Point Defects in Plane-Stressed Si Single Crystal","authors":"K. Sueoka, Yanbo Wang, S. Shiba, S. Fukutani","doi":"10.1299/JCST.2.478","DOIUrl":"https://doi.org/10.1299/JCST.2.478","url":null,"abstract":"The effect of compressive or tensile plane-stress on formation energies and electronic properties of point defects in Si single crystal was studied by first principles approach for in-plane strain up to 5.0 %. It was found that the formation energy of interstitial Si (I) decreased under tensile in-plane strain. On the other hand, the formation energy of vacancy (V) decreased under compressive in-plane strain. The most stable states of I and V in intrinsic Si were I+2 at T site and V0 respectively, independent of type and value of the in-plane strain.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"22 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":"134060500","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, the numerical simulations of incompressible flow with heat transfer are presented by using the seamless immersed boundary method on the Cartesian grid. In the seamless immersed boundary method, the forcing term is added not only on the grid points near the boundary but also on the grid points inside the boundary (solid region) in order to satisfy the velocity boundary condition. Then, the seamless physical quantities, e.g., the pressure, can be obtained, so that the characteristic quantities on the boundary can be estimated precisely. The present seamless immersed boundary method is applied to the energy equation. Then, the temperature satisfying the boundary condition can be easily obtained as well as velocity on the Cartesian grid. The present method is applied to flows around an object with the moving boundary and heat transfer.
{"title":"Numerical Simulation of Incompressible Flows with Heat Transfer using Seamless Immersed Boundary Method","authors":"K. Tajiri, H. Nishida, Mitsuru Tanaka","doi":"10.1299/JCST.7.286","DOIUrl":"https://doi.org/10.1299/JCST.7.286","url":null,"abstract":"In this paper, the numerical simulations of incompressible flow with heat transfer are presented by using the seamless immersed boundary method on the Cartesian grid. In the seamless immersed boundary method, the forcing term is added not only on the grid points near the boundary but also on the grid points inside the boundary (solid region) in order to satisfy the velocity boundary condition. Then, the seamless physical quantities, e.g., the pressure, can be obtained, so that the characteristic quantities on the boundary can be estimated precisely. The present seamless immersed boundary method is applied to the energy equation. Then, the temperature satisfying the boundary condition can be easily obtained as well as velocity on the Cartesian grid. The present method is applied to flows around an object with the moving boundary and heat transfer.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"27 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":"131107459","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, a mixed-mode interfacial crack in three dimensional bimaterials is analyzed by singular integral equations on the basis of the body force method. In the numerical analysis, unknown body force densities are approximated by the products of the fundamental density functions and power series, where the fundamental density functions are chosen to express a two-dimensional interface crack exactly. The results show that the present method yields smooth variations of mixed mode stress intensity factor along the crack front accurately. The effect of crack shape on the stress intensity factor for 3D interface cracks is also discussed on the basis of present solution. Then, it is found that the stress intensity factors KII and KIII are always insensitive to the varying ratio of shear modulus, and determined by Poisson's ratio alone. Distributions of stress intensity factor are indicated in tables and figures with varying the rectangular shape and Poisson's ratio.
{"title":"Variations of Stress Intensity Factors of a Planar Interfacial Crack Subjected to Mixed Mode Loading","authors":"Chun-hui Xu, N. Noda, Y. Takase","doi":"10.1299/JCST.3.232","DOIUrl":"https://doi.org/10.1299/JCST.3.232","url":null,"abstract":"In this paper, a mixed-mode interfacial crack in three dimensional bimaterials is analyzed by singular integral equations on the basis of the body force method. In the numerical analysis, unknown body force densities are approximated by the products of the fundamental density functions and power series, where the fundamental density functions are chosen to express a two-dimensional interface crack exactly. The results show that the present method yields smooth variations of mixed mode stress intensity factor along the crack front accurately. The effect of crack shape on the stress intensity factor for 3D interface cracks is also discussed on the basis of present solution. Then, it is found that the stress intensity factors KII and KIII are always insensitive to the varying ratio of shear modulus, and determined by Poisson's ratio alone. Distributions of stress intensity factor are indicated in tables and figures with varying the rectangular shape and Poisson's ratio.","PeriodicalId":196913,"journal":{"name":"Journal of Computational Science and Technology","volume":"41 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":"133050024","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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