Pub Date : 2022-02-01DOI: 10.31534/engmod.2022.1.ri.03m
A. Semenov
Studying shell structures while accounting for all necessary factors is a significantly nonlinear problem that requires serious mathematical tools and sufficient computing capacities. We propose an approach to solving such problems based on the following numerical methods. We propose the use of the Ritz method, the best parameter continuation method, and the Euler method under static loading. Under dynamic loading, the Kantorovich and the Rosenbrock methods are used. Software implementation was carried out using the Maple analytical software package. This paper also provides examples of simulating the deformation process in shell structures.
{"title":"Mathematical Modeling in Shell Structure Analysis Tasks","authors":"A. Semenov","doi":"10.31534/engmod.2022.1.ri.03m","DOIUrl":"https://doi.org/10.31534/engmod.2022.1.ri.03m","url":null,"abstract":"Studying shell structures while accounting for all necessary factors is a significantly nonlinear problem that requires serious mathematical tools and sufficient computing capacities. We propose an approach to solving such problems based on the following numerical methods. We propose the use of the Ritz method, the best parameter continuation method, and the Euler method under static loading. Under dynamic loading, the Kantorovich and the Rosenbrock methods are used. Software implementation was carried out using the Maple analytical software package. This paper also provides examples of simulating the deformation process in shell structures.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41715675","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}
Pub Date : 2021-11-09DOI: 10.31534/engmod.2021.2.ri.06m
Jadran Čarija, M. Nikolić, Ž. Nikolić
SUMMARY In this paper, we present a novel discrete lattice numerical model for modelling reinforcement in concrete structures. Concrete behaviour is represented here by Voronoi cells and Timoshenko beams as cohesive links between them. Reinforcement bars are explicitly implemented as separate beam elements, while the connection between the concrete and reinforcement is established through the bond elements. Each bond element is positioned between the concrete node and reinforcement node inside the Voronoi cell that crosses the reinforcement bar. Numerical tests are performed to demonstrate the capabilities of the discrete model to predict the response of reinforced concrete structures in the linear elastic stage. The paper also covers the review of different numerical models for modelling reinforced concrete. The overview of research areas in the development of numerical models for reinforced concrete is divided with regards to the manner of modelling cracks, discretisation of the concrete domain and modelling of reinforcement.
{"title":"A Voronoi Based Discrete Numerical Approach for Modelling Reinforcement in Concrete Structures","authors":"Jadran Čarija, M. Nikolić, Ž. Nikolić","doi":"10.31534/engmod.2021.2.ri.06m","DOIUrl":"https://doi.org/10.31534/engmod.2021.2.ri.06m","url":null,"abstract":"SUMMARY In this paper, we present a novel discrete lattice numerical model for modelling reinforcement in concrete structures. Concrete behaviour is represented here by Voronoi cells and Timoshenko beams as cohesive links between them. Reinforcement bars are explicitly implemented as separate beam elements, while the connection between the concrete and reinforcement is established through the bond elements. Each bond element is positioned between the concrete node and reinforcement node inside the Voronoi cell that crosses the reinforcement bar. Numerical tests are performed to demonstrate the capabilities of the discrete model to predict the response of reinforced concrete structures in the linear elastic stage. The paper also covers the review of different numerical models for modelling reinforced concrete. The overview of research areas in the development of numerical models for reinforced concrete is divided with regards to the manner of modelling cracks, discretisation of the concrete domain and modelling of reinforcement.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49533542","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}
Pub Date : 2021-11-03DOI: 10.31534/engmod.2021.2.ri.05d
A. Borni, M. Bechouat, N. Bessous, Abdelhak, Bouchakour, Zarour Laid, L. Zaghba
Many academics have recently focused on wind energy installations. WECS (wind energy conversion system) is a renewable energy source that has seen significant development in recent years. Furthermore, compared to the use of power grid supply, the use of the WECS in the water pumping field is a cost-free option (economically). The purpose of this study is to demonstrate a wind-powered pumping mechanism. To obtain the best option, it considers and contrasts four distinct approaches. This research aims to improve the system's performance and the quality of the generated power. The objective of the control of WECS with a permanent magnet synchronous generator (PMSG) is to carefully maximize power generation. Finally, this research employed the fuzzy logic control (FLC) and particle swarm optimization (PSO) algorithms improved using a genetic algorithm (GA). The proposed system's performance was tested using the generated output voltage, current, and power waveforms, as well as the intermediate circuit voltage waveform and generator speed. The provided data show that the control technique used in this study was effective.
{"title":"Comparative Study of P&O and Fuzzy MPPT Controllers and Their Optimization Using PSO and GA to Improve Wind Energy System","authors":"A. Borni, M. Bechouat, N. Bessous, Abdelhak, Bouchakour, Zarour Laid, L. Zaghba","doi":"10.31534/engmod.2021.2.ri.05d","DOIUrl":"https://doi.org/10.31534/engmod.2021.2.ri.05d","url":null,"abstract":"Many academics have recently focused on wind energy installations. WECS (wind energy conversion system) is a renewable energy source that has seen significant development in recent years. Furthermore, compared to the use of power grid supply, the use of the WECS in the water pumping field is a cost-free option (economically). The purpose of this study is to demonstrate a wind-powered pumping mechanism. To obtain the best option, it considers and contrasts four distinct approaches. This research aims to improve the system's performance and the quality of the generated power. The objective of the control of WECS with a permanent magnet synchronous generator (PMSG) is to carefully maximize power generation. Finally, this research employed the fuzzy logic control (FLC) and particle swarm optimization (PSO) algorithms improved using a genetic algorithm (GA). The proposed system's performance was tested using the generated output voltage, current, and power waveforms, as well as the intermediate circuit voltage waveform and generator speed. The provided data show that the control technique used in this study was effective.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41957321","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}
Pub Date : 2021-10-14DOI: 10.31534/engmod2021.2.ri.04d
N. Talbi, Toufik Sebbagh, A. Metatla
This paper deals with the influence of the shading problem on the electrical production of a photovoltaic generator based on the analysis of the I-V and P-V characteristics of the PV generator for different operating scenarios. The shading problem not only causes energy losses but also increases the non-linearity of the I-V and P-V characteristics of photovoltaic systems. The choice of the model is an essential step to allow analysis and evaluation of the performance of photovoltaic generators. The single diode model was presented in the MATLAB / SIMULINK software. The study began with the presentation of the characteristics of a module, a comparison was made between the values of the obtained electrical parameters and those supplied by the manufacturer. To show the effect of shading on photovoltaic systems another comparative study was presented between a group of series-connected modules and another connected in parallel, both exposed to nonuniform partial shading. The obtained simulation results show that the influence of shading on a set of modules connected in series is greater than that of a set of modules connected in parallel under the same operating conditions.
{"title":"Effect of Nonuniform Partial Shading on the Performance of Photovoltaic Systems","authors":"N. Talbi, Toufik Sebbagh, A. Metatla","doi":"10.31534/engmod2021.2.ri.04d","DOIUrl":"https://doi.org/10.31534/engmod2021.2.ri.04d","url":null,"abstract":"This paper deals with the influence of the shading problem on the electrical production of a photovoltaic generator based on the analysis of the I-V and P-V characteristics of the PV generator for different operating scenarios. The shading problem not only causes energy losses but also increases the non-linearity of the I-V and P-V characteristics of photovoltaic systems. The choice of the model is an essential step to allow analysis and evaluation of the performance of photovoltaic generators. The single diode model was presented in the MATLAB / SIMULINK software. The study began with the presentation of the characteristics of a module, a comparison was made between the values of the obtained electrical parameters and those supplied by the manufacturer. To show the effect of shading on photovoltaic systems another comparative study was presented between a group of series-connected modules and another connected in parallel, both exposed to nonuniform partial shading. The obtained simulation results show that the influence of shading on a set of modules connected in series is greater than that of a set of modules connected in parallel under the same operating conditions.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44533391","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}
Pub Date : 2021-07-22DOI: 10.31534/engmod.2021.2.ri.03d
Zhuang Liang, Jiansheng Wu
SUMMARY Aiming at the obscure features of tumors in rectal CT images and their complexity, this paper proposes a multi-feature fusion-based convolutional neural network rectal tumor recognition method and uses it to model rectal tumors for classification experiments. This method extracts the convolutional features from rectal CT images using Alexnet, VGG16, ResNet, and DenseNet, respectively. At the same time, local features such as histogram of oriented gradient, local binary pattern, and HU moment invariants are extracted from this image. The above local features are fused linearly with the convolutional features. Then we put the new fused features into the fully connected layer for image classification. The experimental results finally reached the accuracy rates of 92.6 %, 93.1 %, 91.7 %, and 91.1 %, respectively. Comparative experiments show that this method improves the accuracy of rectal tumor recognition.
{"title":"Research on Rectal Tumor Identification Method by Convolutional Neural Network Based on Multi-Feature Fusion","authors":"Zhuang Liang, Jiansheng Wu","doi":"10.31534/engmod.2021.2.ri.03d","DOIUrl":"https://doi.org/10.31534/engmod.2021.2.ri.03d","url":null,"abstract":"SUMMARY Aiming at the obscure features of tumors in rectal CT images and their complexity, this paper proposes a multi-feature fusion-based convolutional neural network rectal tumor recognition method and uses it to model rectal tumors for classification experiments. This method extracts the convolutional features from rectal CT images using Alexnet, VGG16, ResNet, and DenseNet, respectively. At the same time, local features such as histogram of oriented gradient, local binary pattern, and HU moment invariants are extracted from this image. The above local features are fused linearly with the convolutional features. Then we put the new fused features into the fully connected layer for image classification. The experimental results finally reached the accuracy rates of 92.6 %, 93.1 %, 91.7 %, and 91.1 %, respectively. Comparative experiments show that this method improves the accuracy of rectal tumor recognition.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45228752","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}
Pub Date : 2021-07-22DOI: 10.31534/engmod.2021.2.ri.02d
Jiawei Miao, Jiansheng Wu
When considering the multi-turn dialogue systems, the model needs to generate a natural and contextual response. At present, HRAN, one of the most advanced models for multi-turn dialogue problems, uses a hierarchical recurrent encoder-decoder combined with a hierarchical attention mechanism. However, for complex conversations, the traditional attention-based RNN does not fully understand the context, which results in attention to the wrong context that generates irrelevant responses. To solve this problem, we proposed an improved hierarchical recurrent attention network, a self-attention network (HSAN), instead of RNN, to learn word representations and utterances representations. Empirical studies on both Chinese and English datasets show that the proposed model has achieved significant improvement.
{"title":"Multi-turn Dialogue Model Based on the Improved Hierarchical Recurrent Attention Network","authors":"Jiawei Miao, Jiansheng Wu","doi":"10.31534/engmod.2021.2.ri.02d","DOIUrl":"https://doi.org/10.31534/engmod.2021.2.ri.02d","url":null,"abstract":"When considering the multi-turn dialogue systems, the model needs to generate a natural and contextual response. At present, HRAN, one of the most advanced models for multi-turn dialogue problems, uses a hierarchical recurrent encoder-decoder combined with a hierarchical attention mechanism. However, for complex conversations, the traditional attention-based RNN does not fully understand the context, which results in attention to the wrong context that generates irrelevant responses. To solve this problem, we proposed an improved hierarchical recurrent attention network, a self-attention network (HSAN), instead of RNN, to learn word representations and utterances representations. Empirical studies on both Chinese and English datasets show that the proposed model has achieved significant improvement.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":"63 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41274607","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}
Pub Date : 2021-06-28DOI: 10.31534/engmod.2021.2.ri.01m
Marko Goreta, N. Torić, I. Boko
SUMMARY The paper presents the development of a creep model applicable for the analysis of aluminium members exposed to a constant temperature. The model is intended as a base for defining a creep model in a transient heating regime. The behaviour of aluminium members exposed to the transient heating regime is a relatively unexplored topic in the scientific community. There is a need for defining an advanced creep model for aluminium, which should cover any heating regime to model the influence of creep on members exposed to fire. A comparison of results between the existing experimental data and the built-in creep models from commercial software ANSYS 16.2 for specific temperature and stress levels is provided. The experimental data used was extracted from previous tests carried out on coupons of aluminium alloy EN 6082 AW T6 and fitted in the aforementioned ANSYS models which serve as a base for defining the representative advanced creep model.
本文介绍了一种适用于分析恒温铝构件的蠕变模型的发展。该模型旨在作为定义瞬态加热状态下蠕变模型的基础。暴露在瞬态加热状态下的铝构件的行为在科学界是一个相对未探索的话题。有必要为铝定义一个先进的蠕变模型，该模型应涵盖任何加热状态，以模拟蠕变对暴露于火灾的构件的影响。在特定温度和应力水平下，将现有实验数据与商业软件ANSYS 16.2的内置蠕变模型的结果进行了比较。所使用的实验数据是从之前对EN 6082 AW T6铝合金试件进行的测试中提取的，并拟合在上述ANSYS模型中，该模型作为定义代表性高级蠕变模型的基础。
{"title":"Calibration of an Existing Creep Model for Analysis of Aluminium Members Exposed to Constant Temperature","authors":"Marko Goreta, N. Torić, I. Boko","doi":"10.31534/engmod.2021.2.ri.01m","DOIUrl":"https://doi.org/10.31534/engmod.2021.2.ri.01m","url":null,"abstract":"SUMMARY The paper presents the development of a creep model applicable for the analysis of aluminium members exposed to a constant temperature. The model is intended as a base for defining a creep model in a transient heating regime. The behaviour of aluminium members exposed to the transient heating regime is a relatively unexplored topic in the scientific community. There is a need for defining an advanced creep model for aluminium, which should cover any heating regime to model the influence of creep on members exposed to fire. A comparison of results between the existing experimental data and the built-in creep models from commercial software ANSYS 16.2 for specific temperature and stress levels is provided. The experimental data used was extracted from previous tests carried out on coupons of aluminium alloy EN 6082 AW T6 and fitted in the aforementioned ANSYS models which serve as a base for defining the representative advanced creep model.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42023500","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}
Pub Date : 2021-06-14DOI: 10.31534/engmod.2021.1.ri.05v
Mohammad Dagdughi, P. L. Chong, Justin A. W. Cox, S. Abdullah
stresses, the mechanical expander dies experience during the expansion are about (10.26%) lower than the pipe’s yield strength. Secondly, the FEA was carried out to investigate the benefit of optimising the mechanical expander dies design on the finished pipe shape. This study showed that reducing the expander die radius by (1%) significantly improves the pipe shape compared to the original expander die size and lowers the stress concentration on the expander dies.
{"title":"Non-linear Analysis of the Expanding Stage in the UOE Pipe Manufacturing Process","authors":"Mohammad Dagdughi, P. L. Chong, Justin A. W. Cox, S. Abdullah","doi":"10.31534/engmod.2021.1.ri.05v","DOIUrl":"https://doi.org/10.31534/engmod.2021.1.ri.05v","url":null,"abstract":"stresses, the mechanical expander dies experience during the expansion are about (10.26%) lower than the pipe’s yield strength. Secondly, the FEA was carried out to investigate the benefit of optimising the mechanical expander dies design on the finished pipe shape. This study showed that reducing the expander die radius by (1%) significantly improves the pipe shape compared to the original expander die size and lowers the stress concentration on the expander dies.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48378258","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}
Since the acoustic impedance in water cannot be neglected with respect to the mechanical impedance, the acoustic radiation caused by the vibration of structures in the compressible fluid would react to the structure. Therefore, the fluid-structure interaction needs to be considered. The finite element method is used for structure vibration analysis and the boundary element method for acoustic analysis. Sound absorption materials are used to reduce the scattering sound field in the reference region. The sensitivity analysis of a fully coupled structural-acoustic system is proposed. Numerical tests verify the correctness of the proposed algorithm.
{"title":"Sensitivity Analysis for Coupled Structural-Acoustic System with Absorbing Material Using FEM/BEM","authors":"Xiu-fang Chen, Ling Yao, Ruhui Cheng, Xiaohui Yuan, Yanming Xu","doi":"10.31534/engmod.2021.1.ri.04f","DOIUrl":"https://doi.org/10.31534/engmod.2021.1.ri.04f","url":null,"abstract":"Since the acoustic impedance in water cannot be neglected with respect to the mechanical impedance, the acoustic radiation caused by the vibration of structures in the compressible fluid would react to the structure. Therefore, the fluid-structure interaction needs to be considered. The finite element method is used for structure vibration analysis and the boundary element method for acoustic analysis. Sound absorption materials are used to reduce the scattering sound field in the reference region. The sensitivity analysis of a fully coupled structural-acoustic system is proposed. Numerical tests verify the correctness of the proposed algorithm.","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42907466","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}
Pub Date : 2021-02-12DOI: 10.31534/ENGMOD.2021.1.RI.01M
Muath Talafha, I. Oldal
ENGINEERING MODELLING 34 (2021) 1, 1-18 1 Evaluation the effect of particle sphericity on direct shear mechanical behavior of granular materials using discrete element method (DEM) Muath S. Talafha(1), Istvan Oldal(2) (1) Department of Mechanics and Engineering Design, Szent István University, Gödöllö, H-2103, pest, HUNGARY e-mail: muath.talafha@gmail.com (2) Department of Mechanics and Engineering Design, Szent István University, Gödöllö, H-2103, pest, HUNGARY e-mail: oldal.istvan@gek.szie.hu
{"title":"Evaluation the effect of particle sphericity on direct shear mechanical behavior of granular materials using discrete element method (DEM)","authors":"Muath Talafha, I. Oldal","doi":"10.31534/ENGMOD.2021.1.RI.01M","DOIUrl":"https://doi.org/10.31534/ENGMOD.2021.1.RI.01M","url":null,"abstract":"ENGINEERING MODELLING 34 (2021) 1, 1-18 1 Evaluation the effect of particle sphericity on direct shear mechanical behavior of granular materials using discrete element method (DEM) Muath S. Talafha(1), Istvan Oldal(2) (1) Department of Mechanics and Engineering Design, Szent István University, Gödöllö, H-2103, pest, HUNGARY e-mail: muath.talafha@gmail.com (2) Department of Mechanics and Engineering Design, Szent István University, Gödöllö, H-2103, pest, HUNGARY e-mail: oldal.istvan@gek.szie.hu","PeriodicalId":35748,"journal":{"name":"International Journal for Engineering Modelling","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47390306","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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