Pub Date : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997636
Jesús O. Ponce, C. Gutiérrez, F. Castillo-Soria
This paper presents an experimental analysis of the depolarization effects that multipath propagation produces on radio-frequency (RF) signals. The analysis is based on the results of a measurement campaign conducted in a suburban scenario in the city of San Luis Potosí, México. Such a campaign collected empirical data of the instantaneous power and Doppler power spectrum (DPS) of an infrastructure-to-vehicle (I2V) channel at 2.45 GHz. The measured data were used to compute three different cross-polarization discriminators (XPD). One of such discriminators has been widely used in the literature to assess the power ratio between co-polarized and cross-polarized signals. The other two discriminators, which are based on the Doppler shift ratio and Doppler spread ratio, are introduced in this paper as new figures of merit to measure the impact of multipath depolarization on the frequency-dispersion characteristics of vehicular RF channels. The results demonstrate that the cross-polarized multipath components of the I2V channel response produce a Doppler frequency dispersion similar to that of the co-polarized components.
{"title":"Experimental Analysis of Depolarization Effects of Infrastructure-to-Vehicle Radio Channels","authors":"Jesús O. Ponce, C. Gutiérrez, F. Castillo-Soria","doi":"10.1109/CONCAPAN48024.2022.9997636","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997636","url":null,"abstract":"This paper presents an experimental analysis of the depolarization effects that multipath propagation produces on radio-frequency (RF) signals. The analysis is based on the results of a measurement campaign conducted in a suburban scenario in the city of San Luis Potosí, México. Such a campaign collected empirical data of the instantaneous power and Doppler power spectrum (DPS) of an infrastructure-to-vehicle (I2V) channel at 2.45 GHz. The measured data were used to compute three different cross-polarization discriminators (XPD). One of such discriminators has been widely used in the literature to assess the power ratio between co-polarized and cross-polarized signals. The other two discriminators, which are based on the Doppler shift ratio and Doppler spread ratio, are introduced in this paper as new figures of merit to measure the impact of multipath depolarization on the frequency-dispersion characteristics of vehicular RF channels. The results demonstrate that the cross-polarized multipath components of the I2V channel response produce a Doppler frequency dispersion similar to that of the co-polarized components.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128856579","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997796
R. Hernandez, Benjamin Hancock, M. Salmeron
This work is a compilation of lessons learned from the analysis of power transformer failures occurred in North and South America based on data collected by Doble Engineering Company over the last ten years. The paper includes annual failure rates and related reports based on voltage rating, failure cause, manufacturing decade, age distribution, among other parameters.
{"title":"Lessons Learned from Analysis of Power Transformer Failure Rates","authors":"R. Hernandez, Benjamin Hancock, M. Salmeron","doi":"10.1109/CONCAPAN48024.2022.9997796","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997796","url":null,"abstract":"This work is a compilation of lessons learned from the analysis of power transformer failures occurred in North and South America based on data collected by Doble Engineering Company over the last ten years. The paper includes annual failure rates and related reports based on voltage rating, failure cause, manufacturing decade, age distribution, among other parameters.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"06 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127252564","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997670
F. Osorio, R. Barazarte
This paper explains the automation process of a deliverability study performed using a 2000-bus synthetic grid on the footprint of Texas [1]. The project algorithm aims to streamline the study process using PTDF analysis and Python scripting automation. The proposed algorithm will simplify the re-dispatch process of available generation during a large-scale N-1 simulation.
{"title":"Generation Re-dispatch and Deliverability Analysis using Power Transfer Distribution Factors","authors":"F. Osorio, R. Barazarte","doi":"10.1109/CONCAPAN48024.2022.9997670","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997670","url":null,"abstract":"This paper explains the automation process of a deliverability study performed using a 2000-bus synthetic grid on the footprint of Texas [1]. The project algorithm aims to streamline the study process using PTDF analysis and Python scripting automation. The proposed algorithm will simplify the re-dispatch process of available generation during a large-scale N-1 simulation.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125416674","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997607
M. Quijano, Guadalupe González
This paper presents the modeling of the adoption of solar photovoltaic generation for residential self-consumption by means of mathematical models to make predictions of the adoption of this technology in upcoming years using real data provided by the National Authority of Public Services (ASEP). It is shown that the growth of residential self-consumption customers by means of PV will not exceed 1% in the next 5 years. On the other hand, several simulations are performed for case studies using the modified 13-node IEEE Test feeder with the addition of residential loads measured in different locations in Panama City and San Miguelito. The effect of photovoltaic penetration for residential self-consumption in this circuit is studied at penetration levels of 0%, 5%, 20%, 50% and 100%. 5 To analyze these case studies, PV generation plants are designed for each residential load with randomly assigned autonomy levels using programs and then the simulation of the complete circuit is performed using OpenDSS. From this research work it can be concluded that, at the moment, for a circuit of this magnitude and with the stipulated characteristics, a change in the regulation of PV systems for self-consumption is not necessarily due to the slow growth in the adoption of the technology. However, if there is an abrupt growth in the adoption of self-consumption at high levels of autonomy and penetration, it is necessary to initiate the construction of a new regulatory framework accompanied by a more detailed study that includes an analysis of harmonics in existing distribution circuits, since these levels may require adjustments in distribution network equipment and greater monitoring of the voltage limits established in the results of these simulations for the IEEE 13-node feeder test.
{"title":"Study of the Penetration of Photovoltaic Energy at the Self-consumption Customer Level using the IEEE 13-Node Test Feeder adapted to Panama","authors":"M. Quijano, Guadalupe González","doi":"10.1109/CONCAPAN48024.2022.9997607","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997607","url":null,"abstract":"This paper presents the modeling of the adoption of solar photovoltaic generation for residential self-consumption by means of mathematical models to make predictions of the adoption of this technology in upcoming years using real data provided by the National Authority of Public Services (ASEP). It is shown that the growth of residential self-consumption customers by means of PV will not exceed 1% in the next 5 years. On the other hand, several simulations are performed for case studies using the modified 13-node IEEE Test feeder with the addition of residential loads measured in different locations in Panama City and San Miguelito. The effect of photovoltaic penetration for residential self-consumption in this circuit is studied at penetration levels of 0%, 5%, 20%, 50% and 100%. 5 To analyze these case studies, PV generation plants are designed for each residential load with randomly assigned autonomy levels using programs and then the simulation of the complete circuit is performed using OpenDSS. From this research work it can be concluded that, at the moment, for a circuit of this magnitude and with the stipulated characteristics, a change in the regulation of PV systems for self-consumption is not necessarily due to the slow growth in the adoption of the technology. However, if there is an abrupt growth in the adoption of self-consumption at high levels of autonomy and penetration, it is necessary to initiate the construction of a new regulatory framework accompanied by a more detailed study that includes an analysis of harmonics in existing distribution circuits, since these levels may require adjustments in distribution network equipment and greater monitoring of the voltage limits established in the results of these simulations for the IEEE 13-node feeder test.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"511 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124471208","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997707
Jaiber Evelio Cardona Aristizábal, J. Gutiérrez
In order to teach automation and control, they must organize laboratory practices that complement the theoretical items. In this sense, automation and control laboratories are expensive and they have reduced access hours. In this work, we show a remote laboratory that is being used by students of the Electronic Engineering career at the University of Quindío. The remote laboratory permits the access to three systems: a neumatic levitator, a 2D robot, and a fly-cutting system. The remote laboratory is offered twenty fourth hours a day, seven days a week. The students can schedule dates and hours for the development of practices, including at night, weekends, or holydays.
{"title":"A remote laboratory platform for teaching automation and control","authors":"Jaiber Evelio Cardona Aristizábal, J. Gutiérrez","doi":"10.1109/CONCAPAN48024.2022.9997707","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997707","url":null,"abstract":"In order to teach automation and control, they must organize laboratory practices that complement the theoretical items. In this sense, automation and control laboratories are expensive and they have reduced access hours. In this work, we show a remote laboratory that is being used by students of the Electronic Engineering career at the University of Quindío. The remote laboratory permits the access to three systems: a neumatic levitator, a 2D robot, and a fly-cutting system. The remote laboratory is offered twenty fourth hours a day, seven days a week. The students can schedule dates and hours for the development of practices, including at night, weekends, or holydays.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128196255","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997741
Andony Reyes Sánchez, Sandro Chavarría Condega
This document presents the functionality of a Simulator Prototype that allows load flows studies, and optimal power flows studies to be carried out in alternating current power systems. The program was developed using the C# and C++ languages with Microsoft Visual Studio. The Newton-Raphson method is used to solve the load flow problem, and a Non-Interior Point method is used to solve the optimal power flow problem. Performance tests were carried out on the prototype from multiple cases of power systems, and satisfactory results were obtained.
{"title":"Study of Load Flows and Optimal Power Flows using a simulator prototype","authors":"Andony Reyes Sánchez, Sandro Chavarría Condega","doi":"10.1109/CONCAPAN48024.2022.9997741","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997741","url":null,"abstract":"This document presents the functionality of a Simulator Prototype that allows load flows studies, and optimal power flows studies to be carried out in alternating current power systems. The program was developed using the C# and C++ languages with Microsoft Visual Studio. The Newton-Raphson method is used to solve the load flow problem, and a Non-Interior Point method is used to solve the optimal power flow problem. Performance tests were carried out on the prototype from multiple cases of power systems, and satisfactory results were obtained.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129969777","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997694
Álvaro Zavala, Leonel Maye
Currently in El Salvador, efforts are being made to implement the digital signature and as part of this technology, a Public Key Infrastructure (PKI) is required, which must validate Certificate Authorities (CA). For a CA, it is necessary to implement the software that allows it to manage digital certificates and perform security procedures for the execution of cryptographic operations, such as encryption, digital signatures, and non-repudiation of electronic transactions. The present work makes a proposal for a digital certificate management system according to the Digital Signature Law of El Salvador and secure cryptography standards. Additionally, a security discussion is accomplished.
{"title":"Application to manage digital certificates as a Certificate Authority (CA) according to the Digital Signature Law of El Salvador","authors":"Álvaro Zavala, Leonel Maye","doi":"10.1109/CONCAPAN48024.2022.9997694","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997694","url":null,"abstract":"Currently in El Salvador, efforts are being made to implement the digital signature and as part of this technology, a Public Key Infrastructure (PKI) is required, which must validate Certificate Authorities (CA). For a CA, it is necessary to implement the software that allows it to manage digital certificates and perform security procedures for the execution of cryptographic operations, such as encryption, digital signatures, and non-repudiation of electronic transactions. The present work makes a proposal for a digital certificate management system according to the Digital Signature Law of El Salvador and secure cryptography standards. Additionally, a security discussion is accomplished.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130967239","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997711
Lata-García Juan, Pérez-Arques Carlos, Cáceres Cesar
One of the routes for the development of isolated communities and stop climate change is the efficient use of renewable energies, in this paper different control strategies are analyzed to manage the energy supply of the model made up of wind turbines, photovoltaic panels, batteries, fuel cell and as a backup subsystem a fuel generator.Control strategies are simulated in the MATLAB-Simulink environment based on component and meteorological data for one year, which knows the behavior of the analyzed system to meet the load demanded.The results of the simulation show that the proposed hybrid system with the controls presented is able to provide the energy demanded by the loads, maintaining a certain energy reserve in the storage sources.
{"title":"Energy management strategies in stand alone hybrid renewable energy systems","authors":"Lata-García Juan, Pérez-Arques Carlos, Cáceres Cesar","doi":"10.1109/CONCAPAN48024.2022.9997711","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997711","url":null,"abstract":"One of the routes for the development of isolated communities and stop climate change is the efficient use of renewable energies, in this paper different control strategies are analyzed to manage the energy supply of the model made up of wind turbines, photovoltaic panels, batteries, fuel cell and as a backup subsystem a fuel generator.Control strategies are simulated in the MATLAB-Simulink environment based on component and meteorological data for one year, which knows the behavior of the analyzed system to meet the load demanded.The results of the simulation show that the proposed hybrid system with the controls presented is able to provide the energy demanded by the loads, maintaining a certain energy reserve in the storage sources.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114738066","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997599
Omar Rivera-Caballero, Alberto Cogley, M. Rios, Jenifer González, Carlos Boya-Lara
In recent years, the use of energy storage systems to provide flexibility to renewable technologies has been identified as a key point to increase the effectiveness of clean technologies and reduce greenhouse gas emissions. In particular, the introduction of energy storage systems with batteries to supply consumers with self-consumption photovoltaic installations has proven to be a viable solution that can present additional benefits. One of these additional benefits can be a positive effect on the distribution network. In this paper, we analyze the potential impacts on the demand side that the integration of battery systems would have on distribution networks with photovoltaic penetration, specifically, the ability to perform peak shaving through battery systems is considered. To validate the potential of the battery system, a distribution system was simulated with real data, and a control strategy was also used to perform the peak shaving task. The results of the simulations indicate that the integration of battery systems can considerably improve peak load reduction by up to 0.2 MW in each phase on the distribution system.
{"title":"Potential Impacts of Demand-side Battery Storage on Distribution Networks with PV Penetration","authors":"Omar Rivera-Caballero, Alberto Cogley, M. Rios, Jenifer González, Carlos Boya-Lara","doi":"10.1109/CONCAPAN48024.2022.9997599","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997599","url":null,"abstract":"In recent years, the use of energy storage systems to provide flexibility to renewable technologies has been identified as a key point to increase the effectiveness of clean technologies and reduce greenhouse gas emissions. In particular, the introduction of energy storage systems with batteries to supply consumers with self-consumption photovoltaic installations has proven to be a viable solution that can present additional benefits. One of these additional benefits can be a positive effect on the distribution network. In this paper, we analyze the potential impacts on the demand side that the integration of battery systems would have on distribution networks with photovoltaic penetration, specifically, the ability to perform peak shaving through battery systems is considered. To validate the potential of the battery system, a distribution system was simulated with real data, and a control strategy was also used to perform the peak shaving task. The results of the simulations indicate that the integration of battery systems can considerably improve peak load reduction by up to 0.2 MW in each phase on the distribution system.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128554313","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997595
Jose Ignacio Rodríguez-Rodríguez, O. Núñez-Mata, G. Gómez-Ramírez
The use of methodologies for condition monitoring of rotating machines has been growing to reduce unplanned downtime and to increase the reliability of the industrial processes. The companies must select a correct maintenance strategy to follow the evolution of rotating machines. Condition monitoring is the collection of data related to the health status of the machine and it has been widely studied so far. Different methodologies have been developed to identify specific behaviors in the condition of induction motors. This paper proposes a methodology for bearing failure detection by using vibrations data, based on the frequency spectrum applied to induction motors. This methodology allows the use of vibration data obtained from motor bearings to establish their condition and therefore determine the type of damage to the bearing. The effectiveness of the proposed methodology is validated using a data set obtained from NASA (National Aeronautics and Space Administration). The results showed that this type of approach is very useful for analyzing bearings and in this way creating maintenance routes based on the condition of the electric machines.
{"title":"Motor bearing failures detection by using vibration data","authors":"Jose Ignacio Rodríguez-Rodríguez, O. Núñez-Mata, G. Gómez-Ramírez","doi":"10.1109/CONCAPAN48024.2022.9997595","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997595","url":null,"abstract":"The use of methodologies for condition monitoring of rotating machines has been growing to reduce unplanned downtime and to increase the reliability of the industrial processes. The companies must select a correct maintenance strategy to follow the evolution of rotating machines. Condition monitoring is the collection of data related to the health status of the machine and it has been widely studied so far. Different methodologies have been developed to identify specific behaviors in the condition of induction motors. This paper proposes a methodology for bearing failure detection by using vibrations data, based on the frequency spectrum applied to induction motors. This methodology allows the use of vibration data obtained from motor bearings to establish their condition and therefore determine the type of damage to the bearing. The effectiveness of the proposed methodology is validated using a data set obtained from NASA (National Aeronautics and Space Administration). The results showed that this type of approach is very useful for analyzing bearings and in this way creating maintenance routes based on the condition of the electric machines.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129732437","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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