Tomoyo Nakayama, Y. Okada, Toshie Kajino, M. Tamashima
{"title":"The Development of Optimized Small Cargo Ship","authors":"Tomoyo Nakayama, Y. Okada, Toshie Kajino, M. Tamashima","doi":"10.2218/marine2021.6803","DOIUrl":"https://doi.org/10.2218/marine2021.6803","url":null,"abstract":"","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127997417","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}
M. Rentschler, P. Chandramouli, G. Vaz, A. Viré, Rodolfo T. Gonçalves
With the advancement of high-performance computation capabilities in recent years, high-fidelity modelling tools such as Computational Fluid Dynamics (CFD) are becoming increasingly popular in the offshore renewable sector. In order to justify the credibility of the numerical simulations, thorough verification and validation is essential. In this work, decay tests for a freely floating cylinder and a linearly moored floating offshore wind turbine (FOWT) model of the OC4 (Offshore Code Comparison Collaboration Continuation) phase II semi-submersible platform are simulated. Two different viscous flow CFD codes are used: OpenFOAM (open-source), and ReFRESCO (community based open-usage). Their results are compared against each other and with water tank experiments. The data from experimental and numerical tests is made freely available on the web hosting platform GitHub 1 , inviting other researchers to join the code comparison and build a reference validation case for floating offshore wind turbines.
{"title":"CFD code comparison, verification and validation for a FOWT semi-submersible floater (OC4 Phase II)","authors":"M. Rentschler, P. Chandramouli, G. Vaz, A. Viré, Rodolfo T. Gonçalves","doi":"10.2218/marine2021.6810","DOIUrl":"https://doi.org/10.2218/marine2021.6810","url":null,"abstract":"With the advancement of high-performance computation capabilities in recent years, high-fidelity modelling tools such as Computational Fluid Dynamics (CFD) are becoming increasingly popular in the offshore renewable sector. In order to justify the credibility of the numerical simulations, thorough verification and validation is essential. In this work, decay tests for a freely floating cylinder and a linearly moored floating offshore wind turbine (FOWT) model of the OC4 (Offshore Code Comparison Collaboration Continuation) phase II semi-submersible platform are simulated. Two different viscous flow CFD codes are used: OpenFOAM (open-source), and ReFRESCO (community based open-usage). Their results are compared against each other and with water tank experiments. The data from experimental and numerical tests is made freely available on the web hosting platform GitHub 1 , inviting other researchers to join the code comparison and build a reference validation case for floating offshore wind turbines.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115606857","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}
Pei-yu Zhang, Yan Li, You-gang Tang, Ruoyu Zhang, X. Qu
In this paper, an articulated offshore wind turbine (AOWT), which consists of ballast tank, buoyancy tank and middle column, is proposed to solve the challenges that both fixed and floating offshore wind turbine couldn’t meet in the the medium-water-depth areas. Through establishing high-dimensional three-objective optimization mathematical model, the main foundation dimensions are determined by non-dominated sorting genetic algorithm Ⅲ (NSGA- Ⅲ ) and corresponding optimization algorithm code is programmed in the MATLAB development environment. In order to to verify the robustness of the AOWT, different severe sea states, including extreme wind speed and extreme stochastic wave scenarios are chosen. For survival sea state, as the turbine is in the parked condition, the aerodynamic load on rotating blades is ignored and the wind pressure loads are calculated based on the empirical formula. The first and second order wave loads are all considered, corresponding hydrodynamic coefficients are simulated by the 3-D potential flow theory. The simulations are conducted in the time domain and dynamic responses are numerically simulated by our in-house aero-hydro coupled code. In previous works, we have investigated AOWT dynamic behaviours under the operational scenarios. It is found that AOWT shows robust performance under the rated sea state. However, as a permanent moored offshore wind turbine, the AOWT will suffer different kinds of severe sea state during its lifetime. Towards this end, we performed a series of simulations to study the AOWT dynamic response under the severe sea status and the results of wave forces, tensions on the articulated joint and foundation motion in the pitch are summarized and analysed. Through the simulation results, we can have a clear understanding of the structure response. The safety and stability of AOWT under different severe sea states are thoroughly investigated, which reflect the validity of physical design to a certain extent. Furthermore, it also points out that the study of dynamic response under severe wave scenarios is necessary for structural design.
{"title":"Study on the Dynamic Behaviours of an Articulated Offshore Wind Turbine under the Severe Sea State","authors":"Pei-yu Zhang, Yan Li, You-gang Tang, Ruoyu Zhang, X. Qu","doi":"10.2218/marine2021.6783","DOIUrl":"https://doi.org/10.2218/marine2021.6783","url":null,"abstract":"In this paper, an articulated offshore wind turbine (AOWT), which consists of ballast tank, buoyancy tank and middle column, is proposed to solve the challenges that both fixed and floating offshore wind turbine couldn’t meet in the the medium-water-depth areas. Through establishing high-dimensional three-objective optimization mathematical model, the main foundation dimensions are determined by non-dominated sorting genetic algorithm Ⅲ (NSGA- Ⅲ ) and corresponding optimization algorithm code is programmed in the MATLAB development environment. In order to to verify the robustness of the AOWT, different severe sea states, including extreme wind speed and extreme stochastic wave scenarios are chosen. For survival sea state, as the turbine is in the parked condition, the aerodynamic load on rotating blades is ignored and the wind pressure loads are calculated based on the empirical formula. The first and second order wave loads are all considered, corresponding hydrodynamic coefficients are simulated by the 3-D potential flow theory. The simulations are conducted in the time domain and dynamic responses are numerically simulated by our in-house aero-hydro coupled code. In previous works, we have investigated AOWT dynamic behaviours under the operational scenarios. It is found that AOWT shows robust performance under the rated sea state. However, as a permanent moored offshore wind turbine, the AOWT will suffer different kinds of severe sea state during its lifetime. Towards this end, we performed a series of simulations to study the AOWT dynamic response under the severe sea status and the results of wave forces, tensions on the articulated joint and foundation motion in the pitch are summarized and analysed. Through the simulation results, we can have a clear understanding of the structure response. The safety and stability of AOWT under different severe sea states are thoroughly investigated, which reflect the validity of physical design to a certain extent. Furthermore, it also points out that the study of dynamic response under severe wave scenarios is necessary for structural design.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"200 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121561929","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 present paper proposes a new flow separation model for the water impact problem which is here solved through by a potential flow model with fully non-linear boundary conditions at the free-surface. The unsteady boundary value problem is numerically solved through a hybrid BEM-FEM approach where a boundary element method is coupled to a simplified finite element method for describing the thinnest part of the jet. In the water entry of bodies with smoothly curved surface, the point where the flow detaches from the body contour is unknown and has to be computed as a part of the numerical solution. For this reason, the hybrid BEM-FEM approach is here extended to include a flow separation model based on a kinematic criterion. The proposed model is applied to the water entry of different smoothly curved body with a constant vertical velocity. Numerical results show the capability of the formulation to accurately describe the free-surface evolution and pressure distribution as well as to provide a consistent prediction of the flow separation.
{"title":"Flow separation model for the water impact problem","authors":"A. Del Buono, A. Iafrati, G. Bernardini","doi":"10.2218/marine2021.6808","DOIUrl":"https://doi.org/10.2218/marine2021.6808","url":null,"abstract":". The present paper proposes a new flow separation model for the water impact problem which is here solved through by a potential flow model with fully non-linear boundary conditions at the free-surface. The unsteady boundary value problem is numerically solved through a hybrid BEM-FEM approach where a boundary element method is coupled to a simplified finite element method for describing the thinnest part of the jet. In the water entry of bodies with smoothly curved surface, the point where the flow detaches from the body contour is unknown and has to be computed as a part of the numerical solution. For this reason, the hybrid BEM-FEM approach is here extended to include a flow separation model based on a kinematic criterion. The proposed model is applied to the water entry of different smoothly curved body with a constant vertical velocity. Numerical results show the capability of the formulation to accurately describe the free-surface evolution and pressure distribution as well as to provide a consistent prediction of the flow separation.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122840043","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}
{"title":"Research of Root Cavitation Erosion","authors":"Masayuki Fukushima, K. Fukuda, T. Tachikawa","doi":"10.2218/marine2021.6813","DOIUrl":"https://doi.org/10.2218/marine2021.6813","url":null,"abstract":"","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114484320","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}
Wave overtopping situations, mainly caused by growing coastal erosion processes, directly affect the populations, causing coastal flooding, damages, and losses. Investments required for the construction and maintenance of coastal defence structures are thus expected to increase in the future over social, environmental and economically valuable coastal areas. The high costs incurred through coastal structures lifetime require improved knowledge on their performance, being important to deliver optimal solutions that consider impacts, costs and benefits. XD-Coast model was developed to facilitate pre-design processes of coastal structures and the COAST model was developed to perform subsequent cost-benefits analysis. However, the first version of XD-Coast does not allow forecasting wave overtopping phenomena. Thus, this work aims to improve the understanding of the overtopping impacts by including this valence in the XD-Coast and COAST numerical models, allowing to evaluate the relation between the structure design cost and the consequent costs due to overtopping and flooding hazard in the search for optimized solutions. Throughout this work it will be discussed the design of rocky revetments (slope and crown level) and their construction costs, with the potential benefits of reducing the overtopping and flooding consequences. A real case study on the Portuguese coast (Ovar) is also analysed. Conclusions demonstrate that the overtopping and flooding data recorded by the Portuguese Environment Agency (APA) and the ability to adequately reproduce it by formulations, can represent a step forward in the estimative of coastal overtopping and flooding impacts and to define a correlation between events and related costs.
{"title":"Wave Overtopping in the Pre-Design of Coastal Works","authors":"M. Lima, C. Coelho, Pombo Rita, Jesus Ana","doi":"10.2218/marine2021.6777","DOIUrl":"https://doi.org/10.2218/marine2021.6777","url":null,"abstract":"Wave overtopping situations, mainly caused by growing coastal erosion processes, directly affect the populations, causing coastal flooding, damages, and losses. Investments required for the construction and maintenance of coastal defence structures are thus expected to increase in the future over social, environmental and economically valuable coastal areas. The high costs incurred through coastal structures lifetime require improved knowledge on their performance, being important to deliver optimal solutions that consider impacts, costs and benefits. XD-Coast model was developed to facilitate pre-design processes of coastal structures and the COAST model was developed to perform subsequent cost-benefits analysis. However, the first version of XD-Coast does not allow forecasting wave overtopping phenomena. Thus, this work aims to improve the understanding of the overtopping impacts by including this valence in the XD-Coast and COAST numerical models, allowing to evaluate the relation between the structure design cost and the consequent costs due to overtopping and flooding hazard in the search for optimized solutions. Throughout this work it will be discussed the design of rocky revetments (slope and crown level) and their construction costs, with the potential benefits of reducing the overtopping and flooding consequences. A real case study on the Portuguese coast (Ovar) is also analysed. Conclusions demonstrate that the overtopping and flooding data recorded by the Portuguese Environment Agency (APA) and the ability to adequately reproduce it by formulations, can represent a step forward in the estimative of coastal overtopping and flooding impacts and to define a correlation between events and related costs.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121724057","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 presents a numerical analysis on the induced relation between hull surface roughness and ship performance and discuss how to maintain hull-surface with cost and environmental impact in mind. The analysis is based on CFD simulation of the ship performance due to change of hull surface roughness condition before/after dry-docking and in-water hull cleaning. A typical tanker ship, KVLCC2 is investigated for 14 different partial cleaning cases. The attainable reduction of propulsive power by hull surface treatment is estimated as an index, Cleaning Efficiency Index ( CEI ). A clear understanding is obtained how hull geometry has profound implication for the effect of roughness on the change of power. Partial hull cleaning of fore-end and stern-aft part of the hull was found to give higher relative CEI than entire hull cleaning. The present study provides guidelines which part of the hull to treat during dry-docking and hull cleaning process with better quality or higher priority if necessary.
{"title":"A STUDY ON THE EFFECT OF HULL SURFACE TREATMENTS ON SHIP PERFORMANCES","authors":"Keun-Cheol Kim, M. Leer-Andersen, S. Werner","doi":"10.2218/marine2021.6785","DOIUrl":"https://doi.org/10.2218/marine2021.6785","url":null,"abstract":"This paper presents a numerical analysis on the induced relation between hull surface roughness and ship performance and discuss how to maintain hull-surface with cost and environmental impact in mind. The analysis is based on CFD simulation of the ship performance due to change of hull surface roughness condition before/after dry-docking and in-water hull cleaning. A typical tanker ship, KVLCC2 is investigated for 14 different partial cleaning cases. The attainable reduction of propulsive power by hull surface treatment is estimated as an index, Cleaning Efficiency Index ( CEI ). A clear understanding is obtained how hull geometry has profound implication for the effect of roughness on the change of power. Partial hull cleaning of fore-end and stern-aft part of the hull was found to give higher relative CEI than entire hull cleaning. The present study provides guidelines which part of the hull to treat during dry-docking and hull cleaning process with better quality or higher priority if necessary.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117151189","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 Simulation Based Design Optimization method for marine propellers using a two-fidelity levels metamodel for global design space exploration and optimization is presented. Response surfaces are built using the co-Kriging approximation, i.e. a multi-output Gaussian process that combines large low-fidelity dataset with few, costly, high-fidelity data. The method is applied for the CFD-based shape optimization of the E779A propeller using, as fidelity levels, two different physical models for the propeller performances prediction, namely a Boundary Element Method (low-fidelity) and a RANSE solver (high-fidelity). Results demonstrate the feasibility of multi-objective, constrained, design procedures, like those involving marine propellers, using these multi-fidelity response surfaces. At the same time, the need of good correlations between low- and high- fidelity data feeding the surrogate models is highlighted as a requisite for robust and reliable predictions using these approximated methods.
{"title":"A Two-fidelity level approach for Marine Propeller Design","authors":"S. Gaggero, G. Vernengo, D. Villa","doi":"10.2218/marine2021.6801","DOIUrl":"https://doi.org/10.2218/marine2021.6801","url":null,"abstract":"A Simulation Based Design Optimization method for marine propellers using a two-fidelity levels metamodel for global design space exploration and optimization is presented. Response surfaces are built using the co-Kriging approximation, i.e. a multi-output Gaussian process that combines large low-fidelity dataset with few, costly, high-fidelity data. The method is applied for the CFD-based shape optimization of the E779A propeller using, as fidelity levels, two different physical models for the propeller performances prediction, namely a Boundary Element Method (low-fidelity) and a RANSE solver (high-fidelity). Results demonstrate the feasibility of multi-objective, constrained, design procedures, like those involving marine propellers, using these multi-fidelity response surfaces. At the same time, the need of good correlations between low- and high- fidelity data feeding the surrogate models is highlighted as a requisite for robust and reliable predictions using these approximated methods.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127576965","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 describes the behaviour of large-length ships built using fibre-reinforced plastic composite materials under fire and large deformations. A novel methodology is proposed in order to analyse inelastic buckling and post-buckling of steel structures due to thermal loading and also extend this to the phenomenon regarded as pyrolysis that is natural in composite structures. The methodology is validated against the literature. A model of a container-ship where a fire scenario located in the engine room is used to demonstrate the methodology against a real case scenario. The section of the cargo hold closest to the engine room is structurally analysed, focusing in the integrity of the bulkhead and the supports of the TEU containers.
{"title":"Non-linear thermo-mechanical buckling approach for composite laminated marine structures","authors":"D. Di Capua, R. Pachecho, J. García, O. Casals","doi":"10.2218/marine2021.6850","DOIUrl":"https://doi.org/10.2218/marine2021.6850","url":null,"abstract":"This paper describes the behaviour of large-length ships built using fibre-reinforced plastic composite materials under fire and large deformations. A novel methodology is proposed in order to analyse inelastic buckling and post-buckling of steel structures due to thermal loading and also extend this to the phenomenon regarded as pyrolysis that is natural in composite structures. The methodology is validated against the literature. A model of a container-ship where a fire scenario located in the engine room is used to demonstrate the methodology against a real case scenario. The section of the cargo hold closest to the engine room is structurally analysed, focusing in the integrity of the bulkhead and the supports of the TEU containers.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128608490","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 vertical propagation of a dredged spoil release and the propagation of the gravity current due to the sediment cloud collapse at the bottom is investigated in the present study. A two-phase numerical model, able to calculate the amount of the detrained material as function of the conditions under which it is disposed, is developed in Fluent. Initially, a 2D case was validated versus experimental and numerical data available in literature. The validation includes the falling time of the sediment cloud, the of the evolution of the cloud bottom as well as the time evolution of the current front. Further, a 3D two-phase model is presented that simulates the complete process of sediment release over a realistic bathymetry and during realistic flow conditions. The outcome of the 3D model shows how the material is distributed on the river bed, during and immediately after the release of sediment by a hopper dredger.
{"title":"3D simulations of dredged sediment disposal plumes over a realistic bathymetry using a two-phase model","authors":"Foteini Kyrousi, B. Decrop","doi":"10.2218/marine2021.6809","DOIUrl":"https://doi.org/10.2218/marine2021.6809","url":null,"abstract":"The vertical propagation of a dredged spoil release and the propagation of the gravity current due to the sediment cloud collapse at the bottom is investigated in the present study. A two-phase numerical model, able to calculate the amount of the detrained material as function of the conditions under which it is disposed, is developed in Fluent. Initially, a 2D case was validated versus experimental and numerical data available in literature. The validation includes the falling time of the sediment cloud, the of the evolution of the cloud bottom as well as the time evolution of the current front. Further, a 3D two-phase model is presented that simulates the complete process of sediment release over a realistic bathymetry and during realistic flow conditions. The outcome of the 3D model shows how the material is distributed on the river bed, during and immediately after the release of sediment by a hopper dredger.","PeriodicalId":367395,"journal":{"name":"The 9th Conference on Computational Methods in Marine Engineering (Marine 2021)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117099001","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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