Pub Date : 2021-10-26DOI: 10.1109/IREC52758.2021.9624902
Saber Krim, M. Mimouni
this paper proposes a performance improvement of water pumping photovoltaic system based on an induction motor drive. The first contribution of this work consists in introducing an Integral Sliding Mode Speed Controller (ISMSC) to the Direct Torque Control (DTC) of the induction motor, in order to enhance the speed regulation loop and increase the system robustness against the motor parameters variation and the sudden variation of the irradiation. The second contribution is to implement the proposed DTC-ISMSC on an FPGA board in order to reduce the sampling period of the system and the delays in the control loop. Moreover, the extract of the maximum power is performed through the Perturb and Observe (P&O) technique. Finally, the performance of the photovoltaic pumping system controlled by the proposed DTC-ISMSC and P&O is demonstrated by digital simulation using Xilinx system generator tool. The ISMSC is compared also with a proportional integral controller. The obtained results have shown the better dynamic performance of the proposed DTC-ISMSC and P&O.
{"title":"Hardware Implementation of a Novel Sliding Mode Controller for Photovoltaic Water Pumping Systems Without Energy Storage","authors":"Saber Krim, M. Mimouni","doi":"10.1109/IREC52758.2021.9624902","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624902","url":null,"abstract":"this paper proposes a performance improvement of water pumping photovoltaic system based on an induction motor drive. The first contribution of this work consists in introducing an Integral Sliding Mode Speed Controller (ISMSC) to the Direct Torque Control (DTC) of the induction motor, in order to enhance the speed regulation loop and increase the system robustness against the motor parameters variation and the sudden variation of the irradiation. The second contribution is to implement the proposed DTC-ISMSC on an FPGA board in order to reduce the sampling period of the system and the delays in the control loop. Moreover, the extract of the maximum power is performed through the Perturb and Observe (P&O) technique. Finally, the performance of the photovoltaic pumping system controlled by the proposed DTC-ISMSC and P&O is demonstrated by digital simulation using Xilinx system generator tool. The ISMSC is compared also with a proportional integral controller. The obtained results have shown the better dynamic performance of the proposed DTC-ISMSC and P&O.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130840533","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624786
N. Lazaar, O. Dia, A. Sharma
Recently, energy harvesting from human motion and its environment has gained considerable interest given its potential to provide safe and clean energy to portable electronic devices. Nevertheless, the energy produced is insufficient to meet the load needs. In this paper, a hybrid photovoltaic/ thermoelectric/piezoelectric system is used along with a Li-ion battery to power a smart cell phone. The model is developed in Matlab/Simulink and includes a preliminary proposal for an energy management system to balance energy production with consumption. The model performance is validated numerically with a standard deviation of 0,14V of the DC Link voltage.
{"title":"Implementation of an energy management strategy for a low power hybrid system: Application on cell phone charging","authors":"N. Lazaar, O. Dia, A. Sharma","doi":"10.1109/IREC52758.2021.9624786","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624786","url":null,"abstract":"Recently, energy harvesting from human motion and its environment has gained considerable interest given its potential to provide safe and clean energy to portable electronic devices. Nevertheless, the energy produced is insufficient to meet the load needs. In this paper, a hybrid photovoltaic/ thermoelectric/piezoelectric system is used along with a Li-ion battery to power a smart cell phone. The model is developed in Matlab/Simulink and includes a preliminary proposal for an energy management system to balance energy production with consumption. The model performance is validated numerically with a standard deviation of 0,14V of the DC Link voltage.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120946288","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624904
Zoubayre El akili, Y. Bouzidi, A. Merabtine, Julien Kauffmann, G. Polidori
Under transient and non-uniform conditions, providing thermal comfort to frail people has become an important research topic. This experimental study aims to analyze the thermal comfort of frail people using a clothed manikin. Thermal sensation and dynamic thermal sensation in a non-uniform thermal environment are also analyzed. During the tests, the air temperature increased from 18°C to 30°C in a controlled test chamber; skin temperatures, core temperatures, and thermal responses were then collected every 30 seconds. The analysis showed a significant difference in terms of thermal sensation and comfort between males and females over time, while there was no significant difference for the dynamic thermal sensation under test conditions. The results also confirmed that the sensation neutral temperature occurs at around 27°C.
{"title":"Experimental Investigation on the Thermal Comfort of the Frail People in a Sitting Posture Under Transient and Non-Uniform Thermal Environments","authors":"Zoubayre El akili, Y. Bouzidi, A. Merabtine, Julien Kauffmann, G. Polidori","doi":"10.1109/IREC52758.2021.9624904","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624904","url":null,"abstract":"Under transient and non-uniform conditions, providing thermal comfort to frail people has become an important research topic. This experimental study aims to analyze the thermal comfort of frail people using a clothed manikin. Thermal sensation and dynamic thermal sensation in a non-uniform thermal environment are also analyzed. During the tests, the air temperature increased from 18°C to 30°C in a controlled test chamber; skin temperatures, core temperatures, and thermal responses were then collected every 30 seconds. The analysis showed a significant difference in terms of thermal sensation and comfort between males and females over time, while there was no significant difference for the dynamic thermal sensation under test conditions. The results also confirmed that the sensation neutral temperature occurs at around 27°C.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130823113","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624764
Maher Soyah
In integrated and sustainable power systems, renewable energies (RE) required to satisfy the electricity demand would be generated in countries or areas with high resources, and exported to other ones. These RE productions and exchanges occur on a 24/7 basis for dozens of power systems at a time and, thus, constitute a high amount of data. Analyzing this big data and extracting out useful information require computing tools.In this work, we present a calculation model that determines power exchanges paths between areas of an integrated and sustainable power system. This would serve for many applications such as tracking power transactions, detecting grid anomalies or estimating energy costs.The model is based on the mathematical concept of topological sort. The implemented algorithm is applied to a test system and results are then exposed and discussed.
{"title":"Exchanged electricity paths calculation in integrated and sustainable power systems using topological sort","authors":"Maher Soyah","doi":"10.1109/IREC52758.2021.9624764","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624764","url":null,"abstract":"In integrated and sustainable power systems, renewable energies (RE) required to satisfy the electricity demand would be generated in countries or areas with high resources, and exported to other ones. These RE productions and exchanges occur on a 24/7 basis for dozens of power systems at a time and, thus, constitute a high amount of data. Analyzing this big data and extracting out useful information require computing tools.In this work, we present a calculation model that determines power exchanges paths between areas of an integrated and sustainable power system. This would serve for many applications such as tracking power transactions, detecting grid anomalies or estimating energy costs.The model is based on the mathematical concept of topological sort. The implemented algorithm is applied to a test system and results are then exposed and discussed.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130824080","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624802
I. Bahloul, M. Bouzid, S. K. El Khil
A new study based on the negative sequence voltage (NSV) method to detect and diagnosis an incipient interturn short-circuit (ITSC) fault of a closed-loop controlled permanent magnet synchronous generator is proposed. The strategy is based on the use of the amplitude and the phase angle of the NSV to detect and diagnosis an inter-turn short circuit fault with the impact of closed loop control system.This paper presents the behavior of the fault on the different variables of the machine. Therefore, the amplitude of the NSV can be considered as an indicator to detect the appearance of ITSC fault while the phase angle of the NSV can be considered as a robust indicator to locate the faulty phase.
{"title":"Interturn Short-circuit Fault Diagnosis of a Closed-loop Controlled PMSG based Wind Turbine System","authors":"I. Bahloul, M. Bouzid, S. K. El Khil","doi":"10.1109/IREC52758.2021.9624802","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624802","url":null,"abstract":"A new study based on the negative sequence voltage (NSV) method to detect and diagnosis an incipient interturn short-circuit (ITSC) fault of a closed-loop controlled permanent magnet synchronous generator is proposed. The strategy is based on the use of the amplitude and the phase angle of the NSV to detect and diagnosis an inter-turn short circuit fault with the impact of closed loop control system.This paper presents the behavior of the fault on the different variables of the machine. Therefore, the amplitude of the NSV can be considered as an indicator to detect the appearance of ITSC fault while the phase angle of the NSV can be considered as a robust indicator to locate the faulty phase.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128080070","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624856
H. Kerras, N. Outili, Ah. Meniai, K. Loubar
Renewable energies are essential for the reduction of greenhouse gas emissions and sustainable development goals achievement. Biodiesel from waste vegetable oils is a promising alternative to fossil diesel. Several researchers show that increasing biodiesel percentages from 0% to 100% can affect the mixture properties such as density, viscosity, pH, humidity, cetane number, low heating value, etc and it can also reduce HC, CO, and PM emissions while increasing NOx emissions. The main objective of this work is to study the effect of adding percentages of soybean biodiesel in fossil diesel (B5 to B80) on some properties such as density, viscosity and cetane number. The results showed that the studied blends met the standards for considered properties, except for the viscosity at high percentage of biodiesel, also the results showed that mixing biodiesel up to an optimal value of around 45% with Algerian diesel is recommended to ensure the respect of norms for density, viscosity and cetane number.
{"title":"Effect of Diesel-Biodiesel blends on mixture properties","authors":"H. Kerras, N. Outili, Ah. Meniai, K. Loubar","doi":"10.1109/IREC52758.2021.9624856","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624856","url":null,"abstract":"Renewable energies are essential for the reduction of greenhouse gas emissions and sustainable development goals achievement. Biodiesel from waste vegetable oils is a promising alternative to fossil diesel. Several researchers show that increasing biodiesel percentages from 0% to 100% can affect the mixture properties such as density, viscosity, pH, humidity, cetane number, low heating value, etc and it can also reduce HC, CO, and PM emissions while increasing NOx emissions. The main objective of this work is to study the effect of adding percentages of soybean biodiesel in fossil diesel (B5 to B80) on some properties such as density, viscosity and cetane number. The results showed that the studied blends met the standards for considered properties, except for the viscosity at high percentage of biodiesel, also the results showed that mixing biodiesel up to an optimal value of around 45% with Algerian diesel is recommended to ensure the respect of norms for density, viscosity and cetane number.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133273790","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624842
Houda Eletri, A. Snoussi, A. Fellah
We provide a modeling, and a contribution to a thermodynamic optimization of a Once Through multistage thermal desalination (MSF) system. A parametric investigation was carried out, which consist of varying certain characteristic parameters of the installation. Obtained results shows that, the increase in the number of stages contributes to the reduction of the specific surface area, in particular up to a number of 15 stages: When the number of stages goes from 10 to 15 the specific surface area decreases by 90m²/(kg/s). Beyond 15 the variation becomes slower. While concerning the variation of the head temperature T0, it is noted that when it increases from 106 ° C to 110 ° C, the specific surface elevates by 8 m²/(kg/s)and the performance ratio increases by 5%. For the effect of seawater, temperature goes from 25 to 30 ° C.
{"title":"Thermodynamic analysis and assessment of a Once Through multistage desalination (MSF)","authors":"Houda Eletri, A. Snoussi, A. Fellah","doi":"10.1109/IREC52758.2021.9624842","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624842","url":null,"abstract":"We provide a modeling, and a contribution to a thermodynamic optimization of a Once Through multistage thermal desalination (MSF) system. A parametric investigation was carried out, which consist of varying certain characteristic parameters of the installation. Obtained results shows that, the increase in the number of stages contributes to the reduction of the specific surface area, in particular up to a number of 15 stages: When the number of stages goes from 10 to 15 the specific surface area decreases by 90m²/(kg/s). Beyond 15 the variation becomes slower. While concerning the variation of the head temperature T0, it is noted that when it increases from 106 ° C to 110 ° C, the specific surface elevates by 8 m²/(kg/s)and the performance ratio increases by 5%. For the effect of seawater, temperature goes from 25 to 30 ° C.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133967929","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624822
Yamina Jouili, Mouna. Ahlem. Ben Youssef, Ben Hamed, L. Sbita
This work is a proposal of the fuel cell stack for brushless dc motor such as Polymer Electrolyte Membrane Fuel Cells (PEMFC). In order, to improve the performance of PEM fuel cells under inputs variation, an efficient algorithm (Perturb and Observe) of the maximum power point tracking is applied to high step-up converter. This converter is used to boost the voltage level of PEMFC stack. Moreover, the commutation techniques based on Hall Effect sensors of BLDC motor drive is implemented. This system is simulated by Matlab/Simulink and the obtained results show the behavior of PEMFC stack and brushless dc motor.
{"title":"Brushless DC motor fed by PEM fuel cell stack for mini UAV's","authors":"Yamina Jouili, Mouna. Ahlem. Ben Youssef, Ben Hamed, L. Sbita","doi":"10.1109/IREC52758.2021.9624822","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624822","url":null,"abstract":"This work is a proposal of the fuel cell stack for brushless dc motor such as Polymer Electrolyte Membrane Fuel Cells (PEMFC). In order, to improve the performance of PEM fuel cells under inputs variation, an efficient algorithm (Perturb and Observe) of the maximum power point tracking is applied to high step-up converter. This converter is used to boost the voltage level of PEMFC stack. Moreover, the commutation techniques based on Hall Effect sensors of BLDC motor drive is implemented. This system is simulated by Matlab/Simulink and the obtained results show the behavior of PEMFC stack and brushless dc motor.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121168803","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624860
Arwa Ben Farhat, C. Adnene
This paper is based on the state of the art of smart grid; it specifies the definition and the characteristic of the smart grids by focusing on the infrastructure responsible for the expansion and the implementation of the Smart grids. We present in this paper, the emergence of the centralized architecture to the decentralized one with distributed production and bidirectional communication between producers and consumers. This paper invokes the problematic of the Smart grid and present the used model and methods based on Artificial neural network for the load forecasting in order to limit the problematic of the Smart metering in Smart grids.
{"title":"The use of ANN for the load forecasting of the end-users in the smart grid","authors":"Arwa Ben Farhat, C. Adnene","doi":"10.1109/IREC52758.2021.9624860","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624860","url":null,"abstract":"This paper is based on the state of the art of smart grid; it specifies the definition and the characteristic of the smart grids by focusing on the infrastructure responsible for the expansion and the implementation of the Smart grids. We present in this paper, the emergence of the centralized architecture to the decentralized one with distributed production and bidirectional communication between producers and consumers. This paper invokes the problematic of the Smart grid and present the used model and methods based on Artificial neural network for the load forecasting in order to limit the problematic of the Smart metering in Smart grids.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116131580","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 : 2021-10-26DOI: 10.1109/IREC52758.2021.9624779
A. Sabaawi, Qusai H. Sultan, M. S. Salim
currently, significant efforts are being paid on the power management strategies for wireless devices. This leads to exploit the electromagnetic waves that are exist in the ambient environment for battery charging. In this paper, the design of a multi band fractal loop antenna for energy harvesting applications is presented. The proposed antenna has compact dimensions and designed to harvest energy from RF base stations of various mobile networks such as GSM, LTE and the future 5G networks. The resonant frequencies for the proposed antenna is within the range of 900 MHz to 5 GHz. CST Studio Suite software is used to simulate the proposed fractal antenna including the characteristics of S-parameters, gain, and radiation pattern. Simulation results showed that the return loss at resonant frequencies goes below -10 dB, which satisfies the requirements of energy harvesting techniques.
目前，人们在无线设备的电源管理策略上付出了巨大的努力。这导致利用存在于周围环境中的电磁波为电池充电。本文介绍了一种用于能量采集的多波段分形环形天线的设计。该天线尺寸紧凑，旨在从GSM、LTE和未来5G网络等各种移动网络的RF基站收集能量。该天线的谐振频率范围为900 MHz至5 GHz。利用CST Studio Suite软件对所提出的分形天线进行了模拟，包括s参数、增益和辐射方向图的特性。仿真结果表明，谐振频率下的回波损耗在-10 dB以下，满足能量收集技术的要求。
{"title":"Design of Multiband Fractal Antenna for Energy Harvesting Applications","authors":"A. Sabaawi, Qusai H. Sultan, M. S. Salim","doi":"10.1109/IREC52758.2021.9624779","DOIUrl":"https://doi.org/10.1109/IREC52758.2021.9624779","url":null,"abstract":"currently, significant efforts are being paid on the power management strategies for wireless devices. This leads to exploit the electromagnetic waves that are exist in the ambient environment for battery charging. In this paper, the design of a multi band fractal loop antenna for energy harvesting applications is presented. The proposed antenna has compact dimensions and designed to harvest energy from RF base stations of various mobile networks such as GSM, LTE and the future 5G networks. The resonant frequencies for the proposed antenna is within the range of 900 MHz to 5 GHz. CST Studio Suite software is used to simulate the proposed fractal antenna including the characteristics of S-parameters, gain, and radiation pattern. Simulation results showed that the return loss at resonant frequencies goes below -10 dB, which satisfies the requirements of energy harvesting techniques.","PeriodicalId":266552,"journal":{"name":"2021 12th International Renewable Energy Congress (IREC)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114580525","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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