The work deals with the design of the hydraulically operated solar tracker used for a photovoltaic (PV) platform. The tracking mechanism is a dual-axis, azimuthal type, the primary axis, that of the daily/diurnal movement, being positioned vertically, which provides a high stability of the entire structure. The actuation in both movement subsystems (daily and elevation) is achieved by using linear actuators, in the subsystem for the daily movement a stroke amplification mechanism being interspersed between the actuator and the rotating part of the support pillar, which constitutes an element of novelty/originality regarding the mechanical device of the solar tracker. The sun tracking is conducted by an open-loop control strategy, based on a predefined step-by-step algorithm, which was designed so that to capture as much as possible incident solar radiation with a minimum energy consumption for achieving the orientation. The modeling and simulation of the solar tracker is carried out in mechatronic concept, by using the virtual prototyping solutions ADAMS (for the mechanical device model) and EASY5 (for the control system model) of MSC Software.
{"title":"Modelling and Simulation of a Hydraulically Operated Solar Tracker","authors":"C. Alexandru","doi":"10.24084/repqj21.383","DOIUrl":"https://doi.org/10.24084/repqj21.383","url":null,"abstract":"The work deals with the design of the hydraulically operated solar tracker used for a photovoltaic (PV) platform. The tracking mechanism is a dual-axis, azimuthal type, the primary axis, that of the daily/diurnal movement, being positioned vertically, which provides a high stability of the entire structure. The actuation in both movement subsystems (daily and elevation) is achieved by using linear actuators, in the subsystem for the daily movement a stroke amplification mechanism being interspersed between the actuator and the rotating part of the support pillar, which constitutes an element of novelty/originality regarding the mechanical device of the solar tracker. The sun tracking is conducted by an open-loop control strategy, based on a predefined step-by-step algorithm, which was designed so that to capture as much as possible incident solar radiation with a minimum energy consumption for achieving the orientation. The modeling and simulation of the solar tracker is carried out in mechatronic concept, by using the virtual prototyping solutions ADAMS (for the mechanical device model) and EASY5 (for the control system model) of MSC Software.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84473670","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}
Tuany Esthefany Barcellos de Carvalho Silva, Daiane Rodrigues dos Santos, Reinaldo Castro Souza
The concentration of carbon dioxide (CO2 ), the main catalyst for global warming, reached an average of 414.7 parts per million in 2021 and 2.3 ppm more than in 2020. This theme is significant and has gained space in global discussions. This research aimed to deal with and analyze essential points in this discussion. With the study, it was possible to point out evidence that Brazil is a country that has been significantly reducing its CO2 emissions, being in the cluster along with IEA member countries that least issue CO2 . With this article, it was possible to point out similar characteristics between the CO2 emissions of the countries, making it possible to highlight three latent variables: countries that have a constant tall or low trend in CO2 emissions, Grouping of countries that showed an upward trend at the beginning of the analyzed period, but with a significant reduction CO2 over time, and countries that have had more discrepant behavior from the others, these being the countries that have a structural breakdown in their time series of CO2 emissions by power generation.
{"title":"Multivariate analysis of CO2 emissions by energy generation in IEA member countries","authors":"Tuany Esthefany Barcellos de Carvalho Silva, Daiane Rodrigues dos Santos, Reinaldo Castro Souza","doi":"10.24084/repqj21.273","DOIUrl":"https://doi.org/10.24084/repqj21.273","url":null,"abstract":"The concentration of carbon dioxide (CO2 ), the main catalyst for global warming, reached an average of 414.7 parts per million in 2021 and 2.3 ppm more than in 2020. This theme is significant and has gained space in global discussions. This research aimed to deal with and analyze essential points in this discussion. With the study, it was possible to point out evidence that Brazil is a country that has been significantly reducing its CO2 emissions, being in the cluster along with IEA member countries that least issue CO2 . With this article, it was possible to point out similar characteristics between the CO2 emissions of the countries, making it possible to highlight three latent variables: countries that have a constant tall or low trend in CO2 emissions, Grouping of countries that showed an upward trend at the beginning of the analyzed period, but with a significant reduction CO2 over time, and countries that have had more discrepant behavior from the others, these being the countries that have a structural breakdown in their time series of CO2 emissions by power generation.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"99 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85780196","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 presented research is dedicated to estimation of the correlation between the level of renewable energy sources and the costs of congestion management in electric networks in selected European countries. Data of six countries in North-West European area (Italy, Spain, Germany, France, Poland and Austria) were investigated. Factors considered included grid congestion costs including re-dispatching costs as well as countertrading costs, gross electricity generation, installed capacity of electric generating facilities, installed capacity of electric non-dispatchable renewable energy sources and total electricity consumption. Special attention is paid to the share of renewable energy sources. It is found that the grid congestion costs are not clearly affected by penetration of non-dispatchable renewables in all the analysed countries and therefore a clear mathematical correlation cannot no be extrapolated with the available data. The results of this research show in general a loose dependency of the grid congestion costs on the penetration of renewables and a strong dependency on the total electrical consumption of the country.
{"title":"Correlation Between Costs of Congestion Management and Share of Renewables in the ENTSOE Continental Europe Synchronous Area","authors":"D. Coll-mayor, A. Balakhontsev, A. Notholt","doi":"10.24084/repqj21.306","DOIUrl":"https://doi.org/10.24084/repqj21.306","url":null,"abstract":"The presented research is dedicated to estimation of the correlation between the level of renewable energy sources and the costs of congestion management in electric networks in selected European countries. Data of six countries in North-West European area (Italy, Spain, Germany, France, Poland and Austria) were investigated. Factors considered included grid congestion costs including re-dispatching costs as well as countertrading costs, gross electricity generation, installed capacity of electric generating facilities, installed capacity of electric non-dispatchable renewable energy sources and total electricity consumption. Special attention is paid to the share of renewable energy sources. It is found that the grid congestion costs are not clearly affected by penetration of non-dispatchable renewables in all the analysed countries and therefore a clear mathematical correlation cannot no be extrapolated with the available data. The results of this research show in general a loose dependency of the grid congestion costs on the penetration of renewables and a strong dependency on the total electrical consumption of the country.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84466229","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}
F. Fernández-Leal, L. Castro-Santos, P. Rubial-Yáñez, I. Lamas-Galdo, D. Cordal Iglesias, A. Alcayde, F. G. Montoya, A. Filgueira-Vizoso
The objective of this work is to create a tool that serves to know the possibilities of manufacturing, storage, assembly, and maintenance of floating marine structures trying to take advantage of the ports and shipyards of Spain. This would help reduce costs and could make this type of energy more profitable. To this end, all the Spanish ports and shipyards have been analyzed, considering the characteristics and possibilities of each of them. In the study, those that did not meet certain essential conditions for the manufacture, storage, assembly, and maintenance of power generation equipment have been discarded.
{"title":"A tool to select offshore renewable energy facilities. The case of study of shipyards and ports in Spain","authors":"F. Fernández-Leal, L. Castro-Santos, P. Rubial-Yáñez, I. Lamas-Galdo, D. Cordal Iglesias, A. Alcayde, F. G. Montoya, A. Filgueira-Vizoso","doi":"10.24084/repqj21.215","DOIUrl":"https://doi.org/10.24084/repqj21.215","url":null,"abstract":"The objective of this work is to create a tool that serves to know the possibilities of manufacturing, storage, assembly, and maintenance of floating marine structures trying to take advantage of the ports and shipyards of Spain. This would help reduce costs and could make this type of energy more profitable. To this end, all the Spanish ports and shipyards have been analyzed, considering the characteristics and possibilities of each of them. In the study, those that did not meet certain essential conditions for the manufacture, storage, assembly, and maintenance of power generation equipment have been discarded.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80222214","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}
Together with the daily variation of load demand in power grids, the continuous integration of offshore and onshore wind farms to feed the grid with green energy has recently led to a severe frequency stability issue due to the extra variation in the generation side. Hence, wind turbines (WTs), among other renewable energy units are required to regulate their output power to mitigate the fluctuation in generated power and support frequency stability. In this paper, model predictive control (MPC) is implemented in an adaptive way to operate WT in de-loading mode under wind disturbances. In addition, to get comprehensive operation of WTs and meet grid code requirements; we present a new grid-forming controller in the WT rotor side converter to emulate the inherent synchronizing and load sharing property of conventional generators. The limitations of rotor speed and rotor side converter are considered in the proposed control approach.
{"title":"Optimal active power control of wind turbines in grid-forming mode","authors":"Bashar Mousa Melhem, Steven Liu","doi":"10.24084/repqj21.220","DOIUrl":"https://doi.org/10.24084/repqj21.220","url":null,"abstract":"Together with the daily variation of load demand in power grids, the continuous integration of offshore and onshore wind farms to feed the grid with green energy has recently led to a severe frequency stability issue due to the extra variation in the generation side. Hence, wind turbines (WTs), among other renewable energy units are required to regulate their output power to mitigate the fluctuation in generated power and support frequency stability. In this paper, model predictive control (MPC) is implemented in an adaptive way to operate WT in de-loading mode under wind disturbances. In addition, to get comprehensive operation of WTs and meet grid code requirements; we present a new grid-forming controller in the WT rotor side converter to emulate the inherent synchronizing and load sharing property of conventional generators. The limitations of rotor speed and rotor side converter are considered in the proposed control approach.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"115 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80344110","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}
F. Nuñez, G. Magallanes, L. Pacheco, N. Luo, J. Vila
The PWRLINKCAR (Power Link Caribbean) is a research project that has the aim of promoting the renewable energies in the Caribbean area. The use of a submarine cable is proposed for the union of the electric markets of Greater and Lesser Antilles. The goal of the project is to extend the renewable energies to the markets of the Caribbean Area by studying, designing, and modelling the interconnectivity of the markets. It is proposed the use of direct current in order to transmit the electricity energy power using HVDC (High Voltage Direct Current) and HVAC (High Voltage Alternating Current) through submarine cables. Regulatory provisions of the different markets are considered. Energy stocks and electricity price reduction are benefits expected by implementing the power link proposed in this work. Moreover, the power link can include optical cable for promoting telecommunications possibilities in the Caribbean area.
PWRLINKCAR (Power Link Caribbean)是一个旨在促进加勒比地区可再生能源发展的研究项目。建议为大安的列斯群岛和小安的列斯群岛的电力市场联合使用海底电缆。该项目的目标是通过研究、设计和模拟市场的互联性，将可再生能源扩展到加勒比地区的市场。提出利用直流技术，通过海底电缆传输HVDC (High Voltage direct current)和HVAC (High Voltage Alternating current)的电能。考虑了不同市场的监管规定。能源库存和电价下降是实施本工作提出的电力链路预期的效益。此外，电力连接可以包括光缆，以促进加勒比地区的电信可能性。
{"title":"The Power Link Caribbean Project","authors":"F. Nuñez, G. Magallanes, L. Pacheco, N. Luo, J. Vila","doi":"10.24084/repqj21.318","DOIUrl":"https://doi.org/10.24084/repqj21.318","url":null,"abstract":"The PWRLINKCAR (Power Link Caribbean) is a research project that has the aim of promoting the renewable energies in the Caribbean area. The use of a submarine cable is proposed for the union of the electric markets of Greater and Lesser Antilles. The goal of the project is to extend the renewable energies to the markets of the Caribbean Area by studying, designing, and modelling the interconnectivity of the markets. It is proposed the use of direct current in order to transmit the electricity energy power using HVDC (High Voltage Direct Current) and HVAC (High Voltage Alternating Current) through submarine cables. Regulatory provisions of the different markets are considered. Energy stocks and electricity price reduction are benefits expected by implementing the power link proposed in this work. Moreover, the power link can include optical cable for promoting telecommunications possibilities in the Caribbean area.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"49 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90823297","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}
Nowadays, the use of inverters is increasing in more and more applications. Environmental awareness is becoming a trend, so more and more people install solar energy systems on their houses, which also require the use of inverters. Higher power levels have led to the emergence of three-level inverters which has opened up new challenges, such as the issue of midpoint voltage balancing. This paper discusses voltage balancing and voltage ripple reduction techniques for three-level inverters with Neutral-Point Clamped (NPC) topology. The balancing is based on injecting zero-sequence voltage component in carrierbased modulation. The viability of the modulation techniques are verified by computer simulation and then tested on hardware.
{"title":"Development and testing midpoint voltage balance algorithms of three-level inverters","authors":"L. Stranyóczky, A. Balogh, Z. Sütő, I. Varjasi","doi":"10.24084/repqj21.382","DOIUrl":"https://doi.org/10.24084/repqj21.382","url":null,"abstract":"Nowadays, the use of inverters is increasing in more and more applications. Environmental awareness is becoming a trend, so more and more people install solar energy systems on their houses, which also require the use of inverters. Higher power levels have led to the emergence of three-level inverters which has opened up new challenges, such as the issue of midpoint voltage balancing. This paper discusses voltage balancing and voltage ripple reduction techniques for three-level inverters with Neutral-Point Clamped (NPC) topology. The balancing is based on injecting zero-sequence voltage component in carrierbased modulation. The viability of the modulation techniques are verified by computer simulation and then tested on hardware.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78109171","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}
Nowadays, multiphase machine drives are considered in many applications, especially for medium and highpower applications. This paper focuses on the topology of the six to three phase (hexaphase) indirect matrix converter (IMC). The matrix converter (MC) is designed based on twelve bidirectional switches for the rectifier stage and six single switches for the inverter stage. It is interfaced to a high-performance, fault-tolerant multiphase permanent magnet synchronous generator (PMSG) on one side and to the grid on the other side. In the literature, the most common MCs are of the three-phase type and papers on multiple input converters (N>3) are not common. This paper deals with all possible configurations of SVM that can be deduced in a hexaphase MC to determine the modulation indexes and then to assess the VTR (Voltage Transfer Ratio). Simulations are performed on a pure inductive load and THD analysis are performed on the input currents of the MC to show the impact of the studied configurations on the system.
{"title":"Power Quality Analysis of Six Phase Indirect Matrix Converter Based on Multi Phase Generator","authors":"Chabi S. Sanni, A. Mpanda, A. El Hajjaji","doi":"10.24084/repqj21.403","DOIUrl":"https://doi.org/10.24084/repqj21.403","url":null,"abstract":"Nowadays, multiphase machine drives are considered in many applications, especially for medium and highpower applications. This paper focuses on the topology of the six to three phase (hexaphase) indirect matrix converter (IMC). The matrix converter (MC) is designed based on twelve bidirectional switches for the rectifier stage and six single switches for the inverter stage. It is interfaced to a high-performance, fault-tolerant multiphase permanent magnet synchronous generator (PMSG) on one side and to the grid on the other side. In the literature, the most common MCs are of the three-phase type and papers on multiple input converters (N>3) are not common. This paper deals with all possible configurations of SVM that can be deduced in a hexaphase MC to determine the modulation indexes and then to assess the VTR (Voltage Transfer Ratio). Simulations are performed on a pure inductive load and THD analysis are performed on the input currents of the MC to show the impact of the studied configurations on the system.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85357371","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}
Microgrids have been recognized for benefits to the electrical system such as improved reliability and reduced transmission costs and pollutant emissions. The study of microgrids makes it necessary to know and quantify the performance of technical aspects and identify characteristics to improve their performance. The paper proposes to evaluate the performance of generation and protection of a microgrid connected to the grid based on a procedure that includes the definition of indicators, the use of Power Factory software to obtain results and the weighting of indicators based on the DEMATEL technique. The laboratory microgrid studied is located at the Universidad Industrial de Santander and has three 1.5 kW photovoltaic systems and meets demands of 5 and 10 kWh/day. The results show that its generation and protection capacities have a high performance.
{"title":"Evaluation of the generation and protection capabilities of a grid-connected microgrid","authors":"J. García, J. Rey, G. Osma","doi":"10.24084/repqj21.283","DOIUrl":"https://doi.org/10.24084/repqj21.283","url":null,"abstract":"Microgrids have been recognized for benefits to the electrical system such as improved reliability and reduced transmission costs and pollutant emissions. The study of microgrids makes it necessary to know and quantify the performance of technical aspects and identify characteristics to improve their performance. The paper proposes to evaluate the performance of generation and protection of a microgrid connected to the grid based on a procedure that includes the definition of indicators, the use of Power Factory software to obtain results and the weighting of indicators based on the DEMATEL technique. The laboratory microgrid studied is located at the Universidad Industrial de Santander and has three 1.5 kW photovoltaic systems and meets demands of 5 and 10 kWh/day. The results show that its generation and protection capacities have a high performance.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"103 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74860543","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}
D. Velasco, L. Guzman, B. Puruncajas, C. Tutivén, Y. Vidal
This work presents a simple damage detection strategy for wind turbine blades. In particular, a vibration analysis-based damage detection methodology is proposed that requires only healthy data and detects damage in different locations of the blade. The stated structural health monitoring strategy is based on the extraction of characteristics using statistical metrics as a technique for the recognition and differentiation of healthy test experiments from damaged test experiments with simulated faults created by added mass. In this manner, several metrics are approached to find those that show better classification in processing the data provided by the sensors. Finally, an evaluation process is performed to detect blade damage. The results show that the proposed RMSE metric performs at an ideal level, making it a promising strategy for the detection of blade damage.
{"title":"Wind turbine blade damage detection using data-driven techniques","authors":"D. Velasco, L. Guzman, B. Puruncajas, C. Tutivén, Y. Vidal","doi":"10.24084/repqj21.357","DOIUrl":"https://doi.org/10.24084/repqj21.357","url":null,"abstract":"This work presents a simple damage detection strategy for wind turbine blades. In particular, a vibration analysis-based damage detection methodology is proposed that requires only healthy data and detects damage in different locations of the blade. The stated structural health monitoring strategy is based on the extraction of characteristics using statistical metrics as a technique for the recognition and differentiation of healthy test experiments from damaged test experiments with simulated faults created by added mass. In this manner, several metrics are approached to find those that show better classification in processing the data provided by the sensors. Finally, an evaluation process is performed to detect blade damage. The results show that the proposed RMSE metric performs at an ideal level, making it a promising strategy for the detection of blade damage.","PeriodicalId":21076,"journal":{"name":"Renewable Energy and Power Quality Journal","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84266605","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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