Pub Date : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425182
Srđan Divac, Branko M. Koprivica
The aim of this paper is to present an approach to representation of instantaneous magnetising power using harmonic components of the corresponding magnetic field and flux density. Magnetising power for a toroidal sample made of grain-oriented electrical steel has been calculated using measured magnetic field and flux density of the sample. The shape of the magnetic flux density waveform has been maintained triangular or sinusoidal during the experiments performed. A description of the experimental setup, a detailed mathematical approach and experimental and calculation results obtained, as well as appropriate discussion are presented in the paper.
{"title":"Representation of Instantaneous Magnetising Power using Harmonic Components","authors":"Srđan Divac, Branko M. Koprivica","doi":"10.1109/ATEE52255.2021.9425182","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425182","url":null,"abstract":"The aim of this paper is to present an approach to representation of instantaneous magnetising power using harmonic components of the corresponding magnetic field and flux density. Magnetising power for a toroidal sample made of grain-oriented electrical steel has been calculated using measured magnetic field and flux density of the sample. The shape of the magnetic flux density waveform has been maintained triangular or sinusoidal during the experiments performed. A description of the experimental setup, a detailed mathematical approach and experimental and calculation results obtained, as well as appropriate discussion are presented in the paper.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134150938","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425216
D. Çeli̇k, M. E. Meral, M. Waseem
The adoption of green energy policies is paid regard to as a major driver for renewable energy production development (REPD) in terms of fossil fuel combustion and the reduction of gas emissions. However, besides several challenges including energy sustainability, global warming and environmental pollution, COVID-19 arose in 2019 has a considerable impact on the REPD, companies and supply chains and decelerated the transition to the sustainable energy world. The industrial and commercial electrical energy users are imposed to restrict their operation during the COVID-19 outbreak. In this regard, this paper examines and investigates the impacts of restrictions and driving forces for the REPD and electrical energy demand in general and during COVID-19. The most critical factors for barriers and driving forces for the REPD have been examined and discussed in detail. Some important statistical data for investments in the energy sector and energy demand before and during COVID-19 have been addressed in detail.
{"title":"Restrictions and Driving Forces for Renewable Energy Production Development and Electrical Energy Demand in General and During COVID-19","authors":"D. Çeli̇k, M. E. Meral, M. Waseem","doi":"10.1109/ATEE52255.2021.9425216","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425216","url":null,"abstract":"The adoption of green energy policies is paid regard to as a major driver for renewable energy production development (REPD) in terms of fossil fuel combustion and the reduction of gas emissions. However, besides several challenges including energy sustainability, global warming and environmental pollution, COVID-19 arose in 2019 has a considerable impact on the REPD, companies and supply chains and decelerated the transition to the sustainable energy world. The industrial and commercial electrical energy users are imposed to restrict their operation during the COVID-19 outbreak. In this regard, this paper examines and investigates the impacts of restrictions and driving forces for the REPD and electrical energy demand in general and during COVID-19. The most critical factors for barriers and driving forces for the REPD have been examined and discussed in detail. Some important statistical data for investments in the energy sector and energy demand before and during COVID-19 have been addressed in detail.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"122 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133779414","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425146
L. Dumitrescu, C. Safta, Ioan Bălan, R. Rădoi, C. Cristescu
The paper is focused on the experimental results regarding the operation of a new energy recovery system. The system is used to electrohydraulic driven a lifting system. The energy recovery method is based on the use of a hydraulic power multiplier cylinder and an accumulator. Three working scenarios are presented and the performance of the system for each operating situation is highlighted and discussed.
{"title":"Experimental Results on an Energy Saving Method Applied to a Hydraulic Driven Lifting System","authors":"L. Dumitrescu, C. Safta, Ioan Bălan, R. Rădoi, C. Cristescu","doi":"10.1109/ATEE52255.2021.9425146","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425146","url":null,"abstract":"The paper is focused on the experimental results regarding the operation of a new energy recovery system. The system is used to electrohydraulic driven a lifting system. The energy recovery method is based on the use of a hydraulic power multiplier cylinder and an accumulator. Three working scenarios are presented and the performance of the system for each operating situation is highlighted and discussed.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125546450","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425156
M. Bilici, L. Calin, A. Cătinean, A. Samuila
The aim of the paper is to show the possibility of using electrostatic technologies for the recovery of non-ferrous metals from the non-conductive fraction obtained in the recycling process of waste electrical and electronic equipment (WEEE). Prior to electrostatic separation, the material undergoes in-situ operations such as size reduction and dust and light component removal. Two granular mixtures of the same material are obtained, a coarse fraction (3.15-6) mm that contains metals, plastics and doesn’t contain any glass and a fine fraction (0-3.15) mm containing metals, plastics and a significant amount of glass. The granular mixtures are then separated using a laboratory version of a conventional roll-type corona-electrostatic separator with an extended charging zone. The virtually pure conductive fraction recovered from the mixtures makes up 4.34% of the initial material and is composed of mainly copper and brass $(gt70$%), along with nickel, zinc, tin, and lead in lower quantities.
{"title":"Increasing the Recovery Rate of Metals from WEEE by Corona-electrostatic Separation","authors":"M. Bilici, L. Calin, A. Cătinean, A. Samuila","doi":"10.1109/ATEE52255.2021.9425156","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425156","url":null,"abstract":"The aim of the paper is to show the possibility of using electrostatic technologies for the recovery of non-ferrous metals from the non-conductive fraction obtained in the recycling process of waste electrical and electronic equipment (WEEE). Prior to electrostatic separation, the material undergoes in-situ operations such as size reduction and dust and light component removal. Two granular mixtures of the same material are obtained, a coarse fraction (3.15-6) mm that contains metals, plastics and doesn’t contain any glass and a fine fraction (0-3.15) mm containing metals, plastics and a significant amount of glass. The granular mixtures are then separated using a laboratory version of a conventional roll-type corona-electrostatic separator with an extended charging zone. The virtually pure conductive fraction recovered from the mixtures makes up 4.34% of the initial material and is composed of mainly copper and brass $(gt70$%), along with nickel, zinc, tin, and lead in lower quantities.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"81 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131622153","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425125
R. Pietraru, Stefan Andrei, M. Nicolae, D. Merezeanu
The current pandemic caused by the SARS-CoV-2 virus has affected all sectors of activity through quarantine measures imposed to stop the spread of the disease. In the absence of safe treatment, social distancing and wearing a face mask are the only weapons to combat this pandemic. Unfortunately, social distance has led to the migration of education to a distance format reducing the interaction between teachers and students. Even if, through the vaccination process, the spread of COVID19 disease will be slowed down, the physical return to schools and universities will be done under the sign of social distancing and health precautions. This article proposes a simple and low-cost solution for monitoring the density of people in a room by monitoring WiFi traffic. Because the solution can be implemented on a large scale, it is suitable for implementation as a centralized monitoring and warning solution at school or university campus level.
{"title":"A WiFi Sniffing Solution for Safe Return to Classes","authors":"R. Pietraru, Stefan Andrei, M. Nicolae, D. Merezeanu","doi":"10.1109/ATEE52255.2021.9425125","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425125","url":null,"abstract":"The current pandemic caused by the SARS-CoV-2 virus has affected all sectors of activity through quarantine measures imposed to stop the spread of the disease. In the absence of safe treatment, social distancing and wearing a face mask are the only weapons to combat this pandemic. Unfortunately, social distance has led to the migration of education to a distance format reducing the interaction between teachers and students. Even if, through the vaccination process, the spread of COVID19 disease will be slowed down, the physical return to schools and universities will be done under the sign of social distancing and health precautions. This article proposes a simple and low-cost solution for monitoring the density of people in a room by monitoring WiFi traffic. Because the solution can be implemented on a large scale, it is suitable for implementation as a centralized monitoring and warning solution at school or university campus level.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134415189","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425244
C. Ciufudean, C. Buzduga
This work comes to the aid of free ride skiers as well as people traveling through the mountains. It can help them know if they are exposed to an avalanche. Our system can detect an avalanche in its infancy or offer the possibility to find out if in that area, under the action of an external mechanical force such as the passage of a skier, snowboarder, a group of people or another force (e.g. pressure caused by waves sound) is likely to trigger an avalanche. The system is designed to send a text message to the mountain rescuer or the competent authorities with GPS coordinates. The system is implemented on a ski stick so that it can be accessible to any skier and not have to take other devices or utensils with him. Further development of our system is mentioned in the last chapter of this article.
{"title":"Avalanche Risk Estimation Automat System","authors":"C. Ciufudean, C. Buzduga","doi":"10.1109/ATEE52255.2021.9425244","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425244","url":null,"abstract":"This work comes to the aid of free ride skiers as well as people traveling through the mountains. It can help them know if they are exposed to an avalanche. Our system can detect an avalanche in its infancy or offer the possibility to find out if in that area, under the action of an external mechanical force such as the passage of a skier, snowboarder, a group of people or another force (e.g. pressure caused by waves sound) is likely to trigger an avalanche. The system is designed to send a text message to the mountain rescuer or the competent authorities with GPS coordinates. The system is implemented on a ski stick so that it can be accessible to any skier and not have to take other devices or utensils with him. Further development of our system is mentioned in the last chapter of this article.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131818562","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425330
Partemie-Marian Mutescu, A. Petrariu, A. Lavric
Internet of Things concept has brought us many sensors application possibilities that aim to make our lives better. The IoT concept entail the use of low-power, low-cost, long-range sensors that can collect data from the environment and send it to the user application using wireless link, for maximum mobility. In this paper we evaluate and compare a couple of the market available LPWAN solutions, trough the energy efficiency perspective. Although LPWAN implies low-power devices, some of the modules used in the experimental setup need a high current burst, making them inefficient if the power supply is not properly sized. Thus, the main contribution of this paper is the energy efficiency analysis of the main existing IoT technologies like LoRa or SigFox. From the obtained results one may conclude that some modules can transmit using high current peaks for short period of time while others can transmit low current peaks for long period of time, being useful only for specific monitoring applications.
{"title":"Wireless Communications for IoT: Energy Efficiency Survey","authors":"Partemie-Marian Mutescu, A. Petrariu, A. Lavric","doi":"10.1109/ATEE52255.2021.9425330","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425330","url":null,"abstract":"Internet of Things concept has brought us many sensors application possibilities that aim to make our lives better. The IoT concept entail the use of low-power, low-cost, long-range sensors that can collect data from the environment and send it to the user application using wireless link, for maximum mobility. In this paper we evaluate and compare a couple of the market available LPWAN solutions, trough the energy efficiency perspective. Although LPWAN implies low-power devices, some of the modules used in the experimental setup need a high current burst, making them inefficient if the power supply is not properly sized. Thus, the main contribution of this paper is the energy efficiency analysis of the main existing IoT technologies like LoRa or SigFox. From the obtained results one may conclude that some modules can transmit using high current peaks for short period of time while others can transmit low current peaks for long period of time, being useful only for specific monitoring applications.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132233884","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425072
A. Duca
This paper studies and proposes a new set of ACOR (Ant Colony optimization for Real domains) algorithms dedicated to electromagnetic problems. The adaptive ACOR adjust their parameters during the iterative process in order to control how the exploration and exploitation are involved and performed in the global optimum search. The strategy is to smoothly alternate between exploration and exploitation, with the first one predominant in the initial stages of the algorithms and the second towards the end. Though the proposed algorithms can be applied to any kind of optimization problem they are tuned and their efficiency is proven on an electromagnetic benchmark problem, namely Loney’s solenoid.
{"title":"Adaptive ACOR to solve the Loney’s solenoid electromagnetic problem","authors":"A. Duca","doi":"10.1109/ATEE52255.2021.9425072","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425072","url":null,"abstract":"This paper studies and proposes a new set of ACOR (Ant Colony optimization for Real domains) algorithms dedicated to electromagnetic problems. The adaptive ACOR adjust their parameters during the iterative process in order to control how the exploration and exploitation are involved and performed in the global optimum search. The strategy is to smoothly alternate between exploration and exploitation, with the first one predominant in the initial stages of the algorithms and the second towards the end. Though the proposed algorithms can be applied to any kind of optimization problem they are tuned and their efficiency is proven on an electromagnetic benchmark problem, namely Loney’s solenoid.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132277765","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425282
Florin Ciuprina, Laura Andrei
The temperature dependent dielectric response of the LDPE-TiO2 nanodielectric with 5wt% TiO2 nanoparticles is presented in this paper. The role played by the nanofiller-polymer interface on this dielectric response is discussed based on results obtained by dielectric spectroscopy measurements performed at temperatures between 300 and 350 K and in the frequency range $10^{-2}-10^{6}$ Hz, but also by numerical modeling and data analysis. The obtained results show that the dielectric response of the tested nanodielectric is by far more intense than the one of the unfilled LDPE. Three thermally activated relaxation processes were emphasized in nanodielectric with respect to the unfilled polymer. All these relaxations are mainly due to the dielectric response of the polymer-nanofiller interface region, which dominates the dielectric behavior of the nanodielectric.
{"title":"Interface Role on Temperature Dependent Dielectric Response of LDPE-TiO2 Nanocomposites","authors":"Florin Ciuprina, Laura Andrei","doi":"10.1109/ATEE52255.2021.9425282","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425282","url":null,"abstract":"The temperature dependent dielectric response of the LDPE-TiO2 nanodielectric with 5wt% TiO2 nanoparticles is presented in this paper. The role played by the nanofiller-polymer interface on this dielectric response is discussed based on results obtained by dielectric spectroscopy measurements performed at temperatures between 300 and 350 K and in the frequency range $10^{-2}-10^{6}$ Hz, but also by numerical modeling and data analysis. The obtained results show that the dielectric response of the tested nanodielectric is by far more intense than the one of the unfilled LDPE. Three thermally activated relaxation processes were emphasized in nanodielectric with respect to the unfilled polymer. All these relaxations are mainly due to the dielectric response of the polymer-nanofiller interface region, which dominates the dielectric behavior of the nanodielectric.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123256155","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 : 2021-03-25DOI: 10.1109/ATEE52255.2021.9425300
S. Enache, A. Câmpeanu, I. Vlad, M. Enache
The research carried out aims at reducing the exploitation costs in case of very high power transformers which operate in the power system. Active and reactive electrical energy losses are high in these transformers and, taking into account their long duration of operation, there result very high exploitation costs. That is why, this paper shows that an optimal design of this transformer, taking also into account the imposed restrictive conditions (gauge dimensions, short-circuit voltage), can substantially reduce this cost. For example, in case of the transformer rated at 250 MVA, optimally designed, the exploitation cost was reduced by $Delta$ce= 14.319%= 1539000$epsilon$, as against the existing transformer. The simulations carried out and presented justify the optimum constructive solution, proposed.
本研究旨在降低大功率变压器在电力系统中运行时的开发成本。这些变压器的有功和无功电能损耗很高，考虑到它们的长时间运行，其开发成本非常高。这就是为什么，本文表明，考虑到所施加的限制条件(仪表尺寸，短路电压)，该变压器的优化设计可以大大降低这一成本。以额定250mva的变压器为例，优化设计后，开发成本降低$Delta$ ce= 14.319%= 1539000$epsilon$, as against the existing transformer. The simulations carried out and presented justify the optimum constructive solution, proposed.
{"title":"Optimization of Design of Very High Power Transformers in Power System","authors":"S. Enache, A. Câmpeanu, I. Vlad, M. Enache","doi":"10.1109/ATEE52255.2021.9425300","DOIUrl":"https://doi.org/10.1109/ATEE52255.2021.9425300","url":null,"abstract":"The research carried out aims at reducing the exploitation costs in case of very high power transformers which operate in the power system. Active and reactive electrical energy losses are high in these transformers and, taking into account their long duration of operation, there result very high exploitation costs. That is why, this paper shows that an optimal design of this transformer, taking also into account the imposed restrictive conditions (gauge dimensions, short-circuit voltage), can substantially reduce this cost. For example, in case of the transformer rated at 250 MVA, optimally designed, the exploitation cost was reduced by $Delta$ce= 14.319%= 1539000$epsilon$, as against the existing transformer. The simulations carried out and presented justify the optimum constructive solution, proposed.","PeriodicalId":359645,"journal":{"name":"2021 12th International Symposium on Advanced Topics in Electrical Engineering (ATEE)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128455894","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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