Pub Date : 2011-10-01DOI: 10.1109/EPQU.2011.6128818
Marián Uher, S. Mišák
For the Smart Grids development is most important knowledge of behaviour of the existing distribution network. For this is used Dynamic Model, which is a software that allows monitoring distribution network behaviour undr varying operating conditions. This softvare is already used by the experts in the field of energy to prepare a regional network switch to a Smart Grid the only built in Czech Republic.
{"title":"Smart region operation optimization using Dynamic Model","authors":"Marián Uher, S. Mišák","doi":"10.1109/EPQU.2011.6128818","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128818","url":null,"abstract":"For the Smart Grids development is most important knowledge of behaviour of the existing distribution network. For this is used Dynamic Model, which is a software that allows monitoring distribution network behaviour undr varying operating conditions. This softvare is already used by the experts in the field of energy to prepare a regional network switch to a Smart Grid the only built in Czech Republic.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"759 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123878318","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128861
V. Monteiro, Henrique Gonçalves, J. Afonso
The large dependency of the imported fossil fuels and the soaring oil prices, makes essential the look for alternatives to the traditional people transportation system. The natural bet is the electric mobility, namely Electric Vehicles (EV), and Plug-in Hybrid Electric Vehicles (PHEV). This way, in this paper is analyzed the potential impacts of the battery charging systems on the grid power quality, in a Smart Grid context. It is considered the current consumed, according to a typical electric consumption profile, and the voltage degradation for a large number of houses. Two different types of EV batteries chargers were considered: a traditional charger; and a smart charger with sinusoidal current consumption and unitary power factor. It presents simulation results of the integration of EVs and PHEVs in terms of power quality, and experimental results of a smart charger which was specially developed for EV charging and that allows mitigation of the power quality degradation.
{"title":"Impact of Electric Vehicles on power quality in a Smart Grid context","authors":"V. Monteiro, Henrique Gonçalves, J. Afonso","doi":"10.1109/EPQU.2011.6128861","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128861","url":null,"abstract":"The large dependency of the imported fossil fuels and the soaring oil prices, makes essential the look for alternatives to the traditional people transportation system. The natural bet is the electric mobility, namely Electric Vehicles (EV), and Plug-in Hybrid Electric Vehicles (PHEV). This way, in this paper is analyzed the potential impacts of the battery charging systems on the grid power quality, in a Smart Grid context. It is considered the current consumed, according to a typical electric consumption profile, and the voltage degradation for a large number of houses. Two different types of EV batteries chargers were considered: a traditional charger; and a smart charger with sinusoidal current consumption and unitary power factor. It presents simulation results of the integration of EVs and PHEVs in terms of power quality, and experimental results of a smart charger which was specially developed for EV charging and that allows mitigation of the power quality degradation.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115803965","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128916
Miguel Marques, R. Castro, M. Almeida
High wind speeds and wide available area at sea have recently increased the global interest on offshore wind farms. As offshore wind farms become larger and are placed further from the shore, the power transmission to the onshore grid becomes a key feature. The objective of this work is to give further insight to HVAC and HVDC-LCC transmission systems. Several compensation schemes for absorbing the excessive reactive power associated to HVAC are evaluated. Furthermore, the benefits of the STATCOM, namely in what concerns its improved voltage control capabilities, are addressed for both technologies. The results obtained bare some similarities, but also important differences, which are highlighted in the paper.
{"title":"Connection of offshore wind parks: HVAC and HVDC-LCC links with STATCOM","authors":"Miguel Marques, R. Castro, M. Almeida","doi":"10.1109/EPQU.2011.6128916","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128916","url":null,"abstract":"High wind speeds and wide available area at sea have recently increased the global interest on offshore wind farms. As offshore wind farms become larger and are placed further from the shore, the power transmission to the onshore grid becomes a key feature. The objective of this work is to give further insight to HVAC and HVDC-LCC transmission systems. Several compensation schemes for absorbing the excessive reactive power associated to HVAC are evaluated. Furthermore, the benefits of the STATCOM, namely in what concerns its improved voltage control capabilities, are addressed for both technologies. The results obtained bare some similarities, but also important differences, which are highlighted in the paper.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134388527","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128821
A. Reis, J. C. de Oliveira, R. Apolonio, H. Bronzeado
Transformers are generally energized by closing the circuit breakers at random times. Consequently, this operation generates high transient inrush currents as a result of the asymmetrical magnetic flux produced in the windings. In light of these facts, this paper presents a strategy to control the switching phenomena which occurs during power transformer inrush. The general idea consists of calculating the pre-existing magnetic fluxes left on the core limbs as a function of operating voltage previously applied to the transformer, just prior to the moment in which de-energization has happened. By using these data and the equations to predict the most suitable closing moments, it is shown the proposal effectiveness at accomplishing the main target here pointed out. Experimental investigations are carried out in order to demonstrate the application method and its validation. The results show the feasibility of building hardware and software structures to drastically reduce the transformer inrush currents.
{"title":"A controlled switching methodology for transformer inrush current elimination: Theory and experimental validation","authors":"A. Reis, J. C. de Oliveira, R. Apolonio, H. Bronzeado","doi":"10.1109/EPQU.2011.6128821","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128821","url":null,"abstract":"Transformers are generally energized by closing the circuit breakers at random times. Consequently, this operation generates high transient inrush currents as a result of the asymmetrical magnetic flux produced in the windings. In light of these facts, this paper presents a strategy to control the switching phenomena which occurs during power transformer inrush. The general idea consists of calculating the pre-existing magnetic fluxes left on the core limbs as a function of operating voltage previously applied to the transformer, just prior to the moment in which de-energization has happened. By using these data and the equations to predict the most suitable closing moments, it is shown the proposal effectiveness at accomplishing the main target here pointed out. Experimental investigations are carried out in order to demonstrate the application method and its validation. The results show the feasibility of building hardware and software structures to drastically reduce the transformer inrush currents.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134574428","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128961
Carlos Patrão, J. Delgado, A. D. de Almeida, Paula Fonseca
This paper presents the main results of a survey conducted in Portugal to evaluate the costs associated with Power Quality disturbances in Industry (more specifically of four typical and most common voltage interruptions). The survey was conducted in different companies from different industrial sectors. Although Power Quality Costs estimation was the main issue of the survey, several other issues were analyzed in order to evaluate important matters such as customer satisfaction. From the analysis of the collected data, the vast majority of companies are satisfied with the Quality of Service provided by the utility, but they indicated the "utility" and "weather conditions" as the main responsible for power supply disturbances. It is clear that the Power Quality disturbances cause high costs to the companies in all the sectors analyzed. This study allowed to get a good picture and to quantify the Portuguese Power Quality Costs related with electrical power supply disturbances.
{"title":"Power Quality Costs estimation in Portuguese industry","authors":"Carlos Patrão, J. Delgado, A. D. de Almeida, Paula Fonseca","doi":"10.1109/EPQU.2011.6128961","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128961","url":null,"abstract":"This paper presents the main results of a survey conducted in Portugal to evaluate the costs associated with Power Quality disturbances in Industry (more specifically of four typical and most common voltage interruptions). The survey was conducted in different companies from different industrial sectors. Although Power Quality Costs estimation was the main issue of the survey, several other issues were analyzed in order to evaluate important matters such as customer satisfaction. From the analysis of the collected data, the vast majority of companies are satisfied with the Quality of Service provided by the utility, but they indicated the \"utility\" and \"weather conditions\" as the main responsible for power supply disturbances. It is clear that the Power Quality disturbances cause high costs to the companies in all the sectors analyzed. This study allowed to get a good picture and to quantify the Portuguese Power Quality Costs related with electrical power supply disturbances.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131494768","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128943
P. Bilik, J. Kvapil, S. Mišák
Supplying of separate isolated load systems such as street lighting can be realized by combination of wind and solar power. Hybrid power supply system consists of a number of independent and different sources of electrical energy with different operating times during different seasons and with energy storage system. Deployment of a hybrid power system is expected in places outside the normal distribution network. For the further research and improvements it is necessary to know in detail the power flow from various sources to the load or to storage battery depending on different seasons. The autonomous monitoring system with remote data transmission system has been developed to monitor the power flow between different blocks of the hybrid power system. The monitoring system also allows efficiency evaluation during various operating modes. The article describes among others the design and implementation of modular and open monitoring system based on virtual instrumentation. The main goal of the article is to describe practical results that can be used to optimize the hybrid power system design in the near future.
{"title":"Efficiency and internal power flow of renewable power supply system","authors":"P. Bilik, J. Kvapil, S. Mišák","doi":"10.1109/EPQU.2011.6128943","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128943","url":null,"abstract":"Supplying of separate isolated load systems such as street lighting can be realized by combination of wind and solar power. Hybrid power supply system consists of a number of independent and different sources of electrical energy with different operating times during different seasons and with energy storage system. Deployment of a hybrid power system is expected in places outside the normal distribution network. For the further research and improvements it is necessary to know in detail the power flow from various sources to the load or to storage battery depending on different seasons. The autonomous monitoring system with remote data transmission system has been developed to monitor the power flow between different blocks of the hybrid power system. The monitoring system also allows efficiency evaluation during various operating modes. The article describes among others the design and implementation of modular and open monitoring system based on virtual instrumentation. The main goal of the article is to describe practical results that can be used to optimize the hybrid power system design in the near future.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132258221","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128828
P. Rezende, J. C. de Oliveira, I. N. Gondim, I. A. Bacca
This paper is aimed at proposing and validating a time domain model for window-type air conditioner apparatus and corresponding insertion in the ATPDraw platform. The suggested computational model performance exactness is evaluated through comparison of simulation and experimental results with ideal and non-ideal supply voltage conditions. Once the representation effectiveness is proven, the model is then implemented in a more comprehensive program developed to cope with the dielectric and thermal relationship between system disturbances and appliance's supportability limits. This tool has been developed so as to provide a scientific and systematized way of analyzing consumer refunding demands to equipment damages eventually attributed to distribution system occurrences. A practical study is then carried out to highlight the overall software application considered here.
{"title":"Air conditioner ATP time domain model and validation focusing reimbursement requests associated with system disturbances","authors":"P. Rezende, J. C. de Oliveira, I. N. Gondim, I. A. Bacca","doi":"10.1109/EPQU.2011.6128828","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128828","url":null,"abstract":"This paper is aimed at proposing and validating a time domain model for window-type air conditioner apparatus and corresponding insertion in the ATPDraw platform. The suggested computational model performance exactness is evaluated through comparison of simulation and experimental results with ideal and non-ideal supply voltage conditions. Once the representation effectiveness is proven, the model is then implemented in a more comprehensive program developed to cope with the dielectric and thermal relationship between system disturbances and appliance's supportability limits. This tool has been developed so as to provide a scientific and systematized way of analyzing consumer refunding demands to equipment damages eventually attributed to distribution system occurrences. A practical study is then carried out to highlight the overall software application considered here.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133006004","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128810
P. Drábek
Power electronic converters produce not only characteristic harmonics, but also both non-characteristic harmonics and interharmonics. This paper presents the physical background of both non-characteristic harmonics and interharmonics. Generation causes are explored and discussed in detail. Extensive series of simulation of different power converter topologies are provided and compared with experimental results and existing standards. This research offers missing background for standards covering low-frequency EMC.
{"title":"Harmonics of power electronic converters","authors":"P. Drábek","doi":"10.1109/EPQU.2011.6128810","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128810","url":null,"abstract":"Power electronic converters produce not only characteristic harmonics, but also both non-characteristic harmonics and interharmonics. This paper presents the physical background of both non-characteristic harmonics and interharmonics. Generation causes are explored and discussed in detail. Extensive series of simulation of different power converter topologies are provided and compared with experimental results and existing standards. This research offers missing background for standards covering low-frequency EMC.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115912355","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128947
F. P. Santilio, J. Oliveira, T. V. Silva, A. Oliveira
Power quality problems related to short or long time voltage variation requires special equipment such as the well-known dynamic voltage regulators to provide acceptable voltage supply at the point of common coupling (PCC) in accordance with the electrical energy agencies regulations. Focusing at achieving an electromagnetic device that would fulfill the above requirements as far as voltage control is concerned a conception of a voltage compensation unit throughout the insertion of series voltages reinforce with the feeder is presented, modeled, simulated and computational disturbance analysis are carried out aiming at investigation the device performance at sudden voltage variation. This allows highlighting the proposal efficiency at regulating both short and long voltage occurrences. This equipment has been here denominated by Electromagnetic Voltage Compensator (EVC) and it combines an electromagnetic structure with a switching module. The proposed equipment has been implemented in the ATPDraw MODELS platform.
{"title":"An electromagnetic voltage regulator proposal throughout the injection of series compensation: Physical conception and computational analysis","authors":"F. P. Santilio, J. Oliveira, T. V. Silva, A. Oliveira","doi":"10.1109/EPQU.2011.6128947","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128947","url":null,"abstract":"Power quality problems related to short or long time voltage variation requires special equipment such as the well-known dynamic voltage regulators to provide acceptable voltage supply at the point of common coupling (PCC) in accordance with the electrical energy agencies regulations. Focusing at achieving an electromagnetic device that would fulfill the above requirements as far as voltage control is concerned a conception of a voltage compensation unit throughout the insertion of series voltages reinforce with the feeder is presented, modeled, simulated and computational disturbance analysis are carried out aiming at investigation the device performance at sudden voltage variation. This allows highlighting the proposal efficiency at regulating both short and long voltage occurrences. This equipment has been here denominated by Electromagnetic Voltage Compensator (EVC) and it combines an electromagnetic structure with a switching module. The proposed equipment has been implemented in the ATPDraw MODELS platform.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125358213","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 : 2011-10-01DOI: 10.1109/EPQU.2011.6128912
Y. Stauffer, E. Onillon, L. Lisowski, C. Meier, P. Theurillat, B. Roustom, G. Francecscutto, R. Marquis, A. Closset, A. Tóth
With the steadily increase of electrical power demand, the pressure on the power grid as well as electricity power bills keep rising. One way of resolving the first issue consists of building more traditional power generation units (fossil, nuclear, hydroelectric …) and building a stronger grid. However, with the democratization of alternative green energy sources more elegant solutions are now becoming viable. Indeed, in the last decade solar panels have not only become affordable but also more efficient. Tackling the energy problem this way permits to relieve the grid but more importantly can also reduce the electricity bill of the user. But given the fluctuant nature of solar energy a smart planning and usage of such energy sources has to be undertaken. In that context a global energy flux optimization is proposed. The latter aims at optimizing the internal (within the house) and external (to and from the main power grid) energy fluxes in a building that is equipped with: solar panels (and the required hardware for domestic voltage generation), a control station (that performs the optimization process and manages the energy fluxes), a battery (for local energy storage), an electrolyzer system (for the car gas production, compression and storage) and a fuel cell powered car This article is the first step of the total energy chain simulation; the article is divided in two main sections. First the different components are described, from a hardware point of view; their interconnections are also highlighted. Focus is naturally given to the control station, which is the core of the energy flux handling. Second, the chosen energy flux modeling formalism will be presented. In that section the optimization (i.e. cost function and constraints) are also discussed in detail. Finally, the conclusion puts in perspective the evolution of the project from a hardware test bench to a fully equipped house.
{"title":"Energy flux optimization in future buildings","authors":"Y. Stauffer, E. Onillon, L. Lisowski, C. Meier, P. Theurillat, B. Roustom, G. Francecscutto, R. Marquis, A. Closset, A. Tóth","doi":"10.1109/EPQU.2011.6128912","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128912","url":null,"abstract":"With the steadily increase of electrical power demand, the pressure on the power grid as well as electricity power bills keep rising. One way of resolving the first issue consists of building more traditional power generation units (fossil, nuclear, hydroelectric …) and building a stronger grid. However, with the democratization of alternative green energy sources more elegant solutions are now becoming viable. Indeed, in the last decade solar panels have not only become affordable but also more efficient. Tackling the energy problem this way permits to relieve the grid but more importantly can also reduce the electricity bill of the user. But given the fluctuant nature of solar energy a smart planning and usage of such energy sources has to be undertaken. In that context a global energy flux optimization is proposed. The latter aims at optimizing the internal (within the house) and external (to and from the main power grid) energy fluxes in a building that is equipped with: solar panels (and the required hardware for domestic voltage generation), a control station (that performs the optimization process and manages the energy fluxes), a battery (for local energy storage), an electrolyzer system (for the car gas production, compression and storage) and a fuel cell powered car This article is the first step of the total energy chain simulation; the article is divided in two main sections. First the different components are described, from a hardware point of view; their interconnections are also highlighted. Focus is naturally given to the control station, which is the core of the energy flux handling. Second, the chosen energy flux modeling formalism will be presented. In that section the optimization (i.e. cost function and constraints) are also discussed in detail. Finally, the conclusion puts in perspective the evolution of the project from a hardware test bench to a fully equipped house.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125377893","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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