Pub Date : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108351
Mahmoud Abu Bandora, Visarion-Cătălin Ifrim, Artiom Moldovan
To determine the efficiency of photovoltaic (PV) systems, the paper proposes a method based on the location of the Maximum Power Point (MPP) and on the principle of dividing the power-point curve into uniform segments. The algorithm detects exactly the highest MPP in the power curve, which was compared to other MPPT algorithms and standard Perturb and Observe (P&O) for partial shading conditions. Also, a comparison between two test cell alternatives was made. The results show that a better shape board algorithm is provided. Acquired results, also, present that the higher output power was obtained from the standard PV system compared to other MPPT algorithms and with the P&O Standard.
为了确定光伏系统的效率，本文提出了一种基于最大功率点(MPP)位置和功率点曲线均匀分段的方法。该算法精确地检测功率曲线中的最高MPP，并将其与其他MPPT算法和部分遮光条件下的标准Perturb and Observe (P&O)进行比较。并对两种试验单元方案进行了比较。结果表明，提出了一种较好的板形算法。获得的结果也表明，与其他MPPT算法和P&O标准相比，标准光伏系统获得了更高的输出功率。
{"title":"PV System Efficiency under Various Conditions by Monitoring the MPPT","authors":"Mahmoud Abu Bandora, Visarion-Cătălin Ifrim, Artiom Moldovan","doi":"10.1109/ATEE58038.2023.10108351","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108351","url":null,"abstract":"To determine the efficiency of photovoltaic (PV) systems, the paper proposes a method based on the location of the Maximum Power Point (MPP) and on the principle of dividing the power-point curve into uniform segments. The algorithm detects exactly the highest MPP in the power curve, which was compared to other MPPT algorithms and standard Perturb and Observe (P&O) for partial shading conditions. Also, a comparison between two test cell alternatives was made. The results show that a better shape board algorithm is provided. Acquired results, also, present that the higher output power was obtained from the standard PV system compared to other MPPT algorithms and with the P&O Standard.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116161014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper focusses on low-pass filters using operational amplifiers. A comparative analysis is made between different types of 4rd order filters (Chebyshev, Butterworth and Bessel) are compared and analysis for various frequencies. The simulations were carried out using the LTspice program. In general, the selection of filters is based on the application for which they must be utilized and the desired performance.
{"title":"Low-Pass Filter Analysis","authors":"Georgiana Rezmeriță, Adelina Bordianu, Steliana Pușcașu","doi":"10.1109/ATEE58038.2023.10108156","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108156","url":null,"abstract":"This paper focusses on low-pass filters using operational amplifiers. A comparative analysis is made between different types of 4rd order filters (Chebyshev, Butterworth and Bessel) are compared and analysis for various frequencies. The simulations were carried out using the LTspice program. In general, the selection of filters is based on the application for which they must be utilized and the desired performance.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123674532","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108196
M. Niţu, A. Aciu, D. Ştefan
The purpose of this paper is to highlight the advantages of applying a preventive and corrective maintenance method in relation to the life of the insulation system of the transformers in operation. This paper proposes a maintenance method based on the revitalization of the insulation of power transformers, in order to extend their life. Two case studies are presented, and the results of the measurements made before and after the revitalization process support the requirements of a preventive and corrective maintenance method.
{"title":"Preventive and Corrective Maintenance for Transformers in Operation","authors":"M. Niţu, A. Aciu, D. Ştefan","doi":"10.1109/ATEE58038.2023.10108196","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108196","url":null,"abstract":"The purpose of this paper is to highlight the advantages of applying a preventive and corrective maintenance method in relation to the life of the insulation system of the transformers in operation. This paper proposes a maintenance method based on the revitalization of the insulation of power transformers, in order to extend their life. Two case studies are presented, and the results of the measurements made before and after the revitalization process support the requirements of a preventive and corrective maintenance method.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126010087","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108364
G. Dumitru, A. Morega, I. Dobrin, D. Enache, A. Dobre, C. Dumitru
This paper presents the numerical modeling results of the temperature for a YBCO-type high-temperature superconducting (HTS) winding of an electromagnet that generates a magnetic field with a maximum magnetic flux density of 5 T. The electromagnet is made in a Helmholtz configuration, with circular double pancake-type coils. Inside the central area of the electromagnet is placed a measuring cell with the sample exposed to the magnetic field, which has a variable temperature in the range of 4.2 to 300 K. The change in the temperature of the HTS winding due to the radiative thermal heat absorbed from the cell, is studied as a function of the temperature of the measuring cell, which can vary between 4.2 K and 300 K. The modeling results shows a maximum value of 0.334 W which give rise of the temperature of the HTS coils to 5 K.
{"title":"Thermal Influence of a Variable Temperature Insert on The High-Temperature Superconductor Coils of a Conduction Cooled High Magnetic Field Generator","authors":"G. Dumitru, A. Morega, I. Dobrin, D. Enache, A. Dobre, C. Dumitru","doi":"10.1109/ATEE58038.2023.10108364","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108364","url":null,"abstract":"This paper presents the numerical modeling results of the temperature for a YBCO-type high-temperature superconducting (HTS) winding of an electromagnet that generates a magnetic field with a maximum magnetic flux density of 5 T. The electromagnet is made in a Helmholtz configuration, with circular double pancake-type coils. Inside the central area of the electromagnet is placed a measuring cell with the sample exposed to the magnetic field, which has a variable temperature in the range of 4.2 to 300 K. The change in the temperature of the HTS winding due to the radiative thermal heat absorbed from the cell, is studied as a function of the temperature of the measuring cell, which can vary between 4.2 K and 300 K. The modeling results shows a maximum value of 0.334 W which give rise of the temperature of the HTS coils to 5 K.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127122104","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108294
Mihai Burlacu, V. Năvrăpescu
In this paper, the impact of different photovoltaic power plants (PVPPs) reactive power control strategies upon a microgrid operation are compared. The first strategies consist in operating the PVPPs at unitary or fixed power factor values, while a local load compensation strategy and an optimal reactive power control strategy, based on the Grey Wolf Optimizer (GWO), are also employed. The microgrid operation is simulated for a one-year period with a one-hour granulation for all considered strategies, and the active power losses, reactive power import and bus voltage levels are compared.
{"title":"Impact Analysis of Optimal Photovoltaic Power Plant Reactive Power Control upon Microgrids Operation","authors":"Mihai Burlacu, V. Năvrăpescu","doi":"10.1109/ATEE58038.2023.10108294","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108294","url":null,"abstract":"In this paper, the impact of different photovoltaic power plants (PVPPs) reactive power control strategies upon a microgrid operation are compared. The first strategies consist in operating the PVPPs at unitary or fixed power factor values, while a local load compensation strategy and an optimal reactive power control strategy, based on the Grey Wolf Optimizer (GWO), are also employed. The microgrid operation is simulated for a one-year period with a one-hour granulation for all considered strategies, and the active power losses, reactive power import and bus voltage levels are compared.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127332886","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108142
Taki Tazwoar Ali, Jobayer Ahmed, Atik Jawad, Nahid-Al-Masood
Renewable energy sources, particularly distributed energy resources (DER), are playing an increasingly important role in the global energy landscape. However, in many power systems, DERs are connected to the same distribution feeder as loads, which can pose challenges in the event of a significant power outage. Specifically, activating the Under Frequency Load Shedding (UFLS) scheme can exacerbate frequency response by disconnecting DERintegrated feeders. To this end, a methodology is proposed in this study to assess the safe disconnection of DERs from a network in various DER penetration scenarios and under specific UFLS settings. The methodology is implemented on a modified version of the South Australian Test System (area 4) using the PSSE simulation platform. The results show that increasing DER integration decreases the allowable limit of DER disconnection to prevent blackout in the grid during an interconnection tripping event. Moreover, a negative linear correlation is observed between the maximum allowable disconnection level of DER and the level of DER penetration, as determined by linear regression analysis. From the relation, the safe operating zone of the DER integrated grid is defined to maintain frequency stability in the event of major power disturbance. This study can function as a useful asset during the grid planning stage for the secure integration of DER on the distribution feeders, taking frequency stability into consideration.
{"title":"Impact of Distributed Energy Resources on the Frequency Response of a Renewable Integrated Grid","authors":"Taki Tazwoar Ali, Jobayer Ahmed, Atik Jawad, Nahid-Al-Masood","doi":"10.1109/ATEE58038.2023.10108142","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108142","url":null,"abstract":"Renewable energy sources, particularly distributed energy resources (DER), are playing an increasingly important role in the global energy landscape. However, in many power systems, DERs are connected to the same distribution feeder as loads, which can pose challenges in the event of a significant power outage. Specifically, activating the Under Frequency Load Shedding (UFLS) scheme can exacerbate frequency response by disconnecting DERintegrated feeders. To this end, a methodology is proposed in this study to assess the safe disconnection of DERs from a network in various DER penetration scenarios and under specific UFLS settings. The methodology is implemented on a modified version of the South Australian Test System (area 4) using the PSSE simulation platform. The results show that increasing DER integration decreases the allowable limit of DER disconnection to prevent blackout in the grid during an interconnection tripping event. Moreover, a negative linear correlation is observed between the maximum allowable disconnection level of DER and the level of DER penetration, as determined by linear regression analysis. From the relation, the safe operating zone of the DER integrated grid is defined to maintain frequency stability in the event of major power disturbance. This study can function as a useful asset during the grid planning stage for the secure integration of DER on the distribution feeders, taking frequency stability into consideration.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131279433","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108264
George Onoja Idoko
This paper presents a viable solution to range anxiety experienced by drivers of electric cars. It describes and shows the application of metaheuristics in pathfinding optimization. Particle swarm optimization, which is a metaheuristic optimization method, is used to optimize a travel path for electric vehicles between Bucharest and Cluj-Napoca. The travel path links the driver to the electric vehicle charging stations on their path.
{"title":"Drive Path Optimization for Electric Vehicles Using Particle Swarm Optimization","authors":"George Onoja Idoko","doi":"10.1109/ATEE58038.2023.10108264","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108264","url":null,"abstract":"This paper presents a viable solution to range anxiety experienced by drivers of electric cars. It describes and shows the application of metaheuristics in pathfinding optimization. Particle swarm optimization, which is a metaheuristic optimization method, is used to optimize a travel path for electric vehicles between Bucharest and Cluj-Napoca. The travel path links the driver to the electric vehicle charging stations on their path.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129028906","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108114
Cristian Vidan, Ioana-Adina Popescu, T. Grigorie
In this paper, a dual battery power supply system is conceptually presented. It is based on the switching of the power supply from two batteries that power the systems on board an UAV with VTOL capabilities. So, the propulsion systems and batteries are determined using mathematical formulas and eCalc software. Therefore, the overall electrical diagram of the on-board electrical network is presented and the sections of the conductors on board the aircraft are calculated. Also, this paper presents the design stages of a dual battery system, the methods of determining the energy consumers on board the UAV, as well as the comparative performance between the proposed system and a classic system with a single battery. These performances are presented through relevant graphs that compare flight time, flight distance and the efficiency of the propulsion system in both configurations.
{"title":"Conceptual Design of a Dual Battery Power Supply System for a Fixed-wing VTOL UAV","authors":"Cristian Vidan, Ioana-Adina Popescu, T. Grigorie","doi":"10.1109/ATEE58038.2023.10108114","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108114","url":null,"abstract":"In this paper, a dual battery power supply system is conceptually presented. It is based on the switching of the power supply from two batteries that power the systems on board an UAV with VTOL capabilities. So, the propulsion systems and batteries are determined using mathematical formulas and eCalc software. Therefore, the overall electrical diagram of the on-board electrical network is presented and the sections of the conductors on board the aircraft are calculated. Also, this paper presents the design stages of a dual battery system, the methods of determining the energy consumers on board the UAV, as well as the comparative performance between the proposed system and a classic system with a single battery. These performances are presented through relevant graphs that compare flight time, flight distance and the efficiency of the propulsion system in both configurations.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"30-31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117190406","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108246
C. Suru, M. Popescu, A. Bitoleanu
The aim of this paper is the substantiation, implementation and validation of a principle to limit the switching frequency for the closed loop current control systems based on hysteresis controllers. The proposed system was designed for a traction system for electric locomotives based on voltage inverter and induction motor with rotor field orientation control. As the switching frequency depends on the system parameters and the chosen hysteresis band, the frequency limitation is obtained by adapting the hysteresis band on the measured mean switching frequency. This system is capable to reduce the mean switching frequency to the imposed value as the frequency controller is able to increase the hysteresis band from a minimum value to a maximum value. The switching frequency remains variable, but it is sufficiently lowered to reduce the switching losses and to avoid the power IGBTs to exceed the maximum switching frequency.
{"title":"Hysteresis Current Controllers with Limited Switching Frequency for Electric Traction Systems with Asynchronous Motor and Rotor Field Orientation Control","authors":"C. Suru, M. Popescu, A. Bitoleanu","doi":"10.1109/ATEE58038.2023.10108246","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108246","url":null,"abstract":"The aim of this paper is the substantiation, implementation and validation of a principle to limit the switching frequency for the closed loop current control systems based on hysteresis controllers. The proposed system was designed for a traction system for electric locomotives based on voltage inverter and induction motor with rotor field orientation control. As the switching frequency depends on the system parameters and the chosen hysteresis band, the frequency limitation is obtained by adapting the hysteresis band on the measured mean switching frequency. This system is capable to reduce the mean switching frequency to the imposed value as the frequency controller is able to increase the hysteresis band from a minimum value to a maximum value. The switching frequency remains variable, but it is sufficiently lowered to reduce the switching losses and to avoid the power IGBTs to exceed the maximum switching frequency.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123031799","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 : 2023-03-23DOI: 10.1109/ATEE58038.2023.10108248
R. Paraschiv, T. Paraschiv, C. Banica, Andrei Ignat, Oana-Isabela Ştirbu, F. Adochiei
Different types of brain electrical activity investigations may provide valuable information for understanding mental states. Lack of anxiety, stress, and attention must be addressed appropriately to develop a healthy society. According to current studies, the assessment and differentiation between different mental states are still based on questionnaires, and there are still no standard digitalized tools to help diagnose. Unlike other research teams, we studied neural changes and aimed to identify and classify mental states by performing electroencephalographic (EEG) signal processing. So, we developed an algorithm for diagnosing anxiety, stress, and attention levels. The algorithm's basis is a mathematical apparatus that provides three indexes to assess attention, anxiety, and stress levels. The algorithm could contribute to many therapies as a support tool, such as Neurofeedback therapy, Mindfulness-based interventions, Biofeedback therapy, Cognitive restructuring therapy, and Cognitive behavioral therapy (CBT). In addition, our algorithm can provide valuable contributions in other related domains such as Clinical psychology, Neuropsychology, Human-computer interaction, Education, Sports Psychology, etc.
{"title":"An Algorithm for Quantifying Anxiety, Stress, and Attention: Towards Objective Assessment of Mental States","authors":"R. Paraschiv, T. Paraschiv, C. Banica, Andrei Ignat, Oana-Isabela Ştirbu, F. Adochiei","doi":"10.1109/ATEE58038.2023.10108248","DOIUrl":"https://doi.org/10.1109/ATEE58038.2023.10108248","url":null,"abstract":"Different types of brain electrical activity investigations may provide valuable information for understanding mental states. Lack of anxiety, stress, and attention must be addressed appropriately to develop a healthy society. According to current studies, the assessment and differentiation between different mental states are still based on questionnaires, and there are still no standard digitalized tools to help diagnose. Unlike other research teams, we studied neural changes and aimed to identify and classify mental states by performing electroencephalographic (EEG) signal processing. So, we developed an algorithm for diagnosing anxiety, stress, and attention levels. The algorithm's basis is a mathematical apparatus that provides three indexes to assess attention, anxiety, and stress levels. The algorithm could contribute to many therapies as a support tool, such as Neurofeedback therapy, Mindfulness-based interventions, Biofeedback therapy, Cognitive restructuring therapy, and Cognitive behavioral therapy (CBT). In addition, our algorithm can provide valuable contributions in other related domains such as Clinical psychology, Neuropsychology, Human-computer interaction, Education, Sports Psychology, etc.","PeriodicalId":398894,"journal":{"name":"2023 13th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131414184","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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