Pub Date : 2011-10-01DOI: 10.1109/EPQU.2011.6128936
A. Lipsky, N. Miteva
This article presents an approach for estimating the permissible ratio between reactive power consumption by rapid variable loads, such as electric arc furnaces and rolling mills, and short-circuit power of power supply networks from the standpoint of errors in calculation of the voltage fluctuation values. The appearance of errors caused by electromagnetic rapid and significant changes in magnitude of reactive power consumption of the above mentioned loads and the corresponding voltage fluctuations at different points in the power system. The transients of a turbogenerator with a typical diagram of its excitation control system and various mathematical models of generators were analyzed. The limiting ratio between the standard deviations of the reactive power consumption variations by the rapid variable loads and the power network parameter was evaluated. This value corresponds to the conditions, when it is possible to neglect the appearance of the electromagnetic transients in the power supply system generators during voltage fluctuation calculations at the connection point to the power network of the aforementioned loads.
{"title":"The influence of power system dynamic regimes on high voltage distribution networks","authors":"A. Lipsky, N. Miteva","doi":"10.1109/EPQU.2011.6128936","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128936","url":null,"abstract":"This article presents an approach for estimating the permissible ratio between reactive power consumption by rapid variable loads, such as electric arc furnaces and rolling mills, and short-circuit power of power supply networks from the standpoint of errors in calculation of the voltage fluctuation values. The appearance of errors caused by electromagnetic rapid and significant changes in magnitude of reactive power consumption of the above mentioned loads and the corresponding voltage fluctuations at different points in the power system. The transients of a turbogenerator with a typical diagram of its excitation control system and various mathematical models of generators were analyzed. The limiting ratio between the standard deviations of the reactive power consumption variations by the rapid variable loads and the power network parameter was evaluated. This value corresponds to the conditions, when it is possible to neglect the appearance of the electromagnetic transients in the power supply system generators during voltage fluctuation calculations at the connection point to the power network of the aforementioned loads.","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":"133350911","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.2011.6128904
W. Wysocki, M. Szlosek
From year to year the energy losses in transmission and distribution networks are reduced because losses of energy are also losing of money. Moreover energy losses are considered to be environment unfriendly. On the other hand, today the high level of energy losses just goes to show that the economy and management of power flow in the power network is incorrect. It can be also connected with some technical issues, which still wait to be resolved. In distribution network the Flexible Alternating Current Transmission Systems (FACTS) effectively reduce losses, improve the voltage conditions and power flow in power networks.
{"title":"Compensation of reactive power as a method for reducing energy losses: On the example of calculations and measurements of load flow through the distribution transformer in one of the polish distribution network","authors":"W. Wysocki, M. Szlosek","doi":"10.1109/EPQU.2011.6128904","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128904","url":null,"abstract":"From year to year the energy losses in transmission and distribution networks are reduced because losses of energy are also losing of money. Moreover energy losses are considered to be environment unfriendly. On the other hand, today the high level of energy losses just goes to show that the economy and management of power flow in the power network is incorrect. It can be also connected with some technical issues, which still wait to be resolved. In distribution network the Flexible Alternating Current Transmission Systems (FACTS) effectively reduce losses, improve the voltage conditions and power flow in power networks.","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":"128897762","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.2011.6128822
Herie Park, M. Ruellan, A. Bouvet, E. Monmasson, R. Bennacer
In order to reduce heat energy demand in residential building, thermal insulation and indoor air tightness become more important. However, in a well-insulated environment, internal heat gain caused by solar radiation, metabolism and losses of home electric appliance (i.e. refrigerator, lamp, television, etc.) can be dominant to home global energy management. To quantify and to modelize the heat gain due to home appliances, we begin experimental measurements in a well-insulated room. The first step in this work is the identification of the room. In this paper we suggest a 1R1C lumped parameter circuit which presents a building thermal model using thermal-electric analogy. Then, we identify the circuit components (the global thermal resistor and the global thermal capacitor) from the heat balance equation and experimental results. Based on the model and the obtained parameters, we simulate the indoor temperature of the model using Matlab/Simulink. To check its accuracy we compare the measured data and simulation results and calculate their error ratio.
{"title":"Thermal parameter identification of simplified building model with electric appliance","authors":"Herie Park, M. Ruellan, A. Bouvet, E. Monmasson, R. Bennacer","doi":"10.1109/EPQU.2011.6128822","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128822","url":null,"abstract":"In order to reduce heat energy demand in residential building, thermal insulation and indoor air tightness become more important. However, in a well-insulated environment, internal heat gain caused by solar radiation, metabolism and losses of home electric appliance (i.e. refrigerator, lamp, television, etc.) can be dominant to home global energy management. To quantify and to modelize the heat gain due to home appliances, we begin experimental measurements in a well-insulated room. The first step in this work is the identification of the room. In this paper we suggest a 1R1C lumped parameter circuit which presents a building thermal model using thermal-electric analogy. Then, we identify the circuit components (the global thermal resistor and the global thermal capacitor) from the heat balance equation and experimental results. Based on the model and the obtained parameters, we simulate the indoor temperature of the model using Matlab/Simulink. To check its accuracy we compare the measured data and simulation results and calculate their error ratio.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"27 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":"134628943","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.2011.6128964
A. S. Masoum, P. Moses, M. Masoum
This paper studies the effects of voltage swells on the behavior of three-phase three-leg power asymmetric power transformers. Based on electric and magnetic circuit topologies, a nonlinear model of a three-phase three-leg transformer is implemented for this study. Electromagnetic transient behavior exhibited in transformer voltages, currents and magnetic fluxes are computed and analyzed in time-domain. Simulations are performed for various voltage swell conditions with different magnitudes, starting and termination (recovery instant waveform) angles and durations. The impacts on the deterioration of power quality in input and output current and voltage waveforms are examined.
{"title":"Operation of three-phase three-leg power transformers subject to voltage swell","authors":"A. S. Masoum, P. Moses, M. Masoum","doi":"10.1109/EPQU.2011.6128964","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128964","url":null,"abstract":"This paper studies the effects of voltage swells on the behavior of three-phase three-leg power asymmetric power transformers. Based on electric and magnetic circuit topologies, a nonlinear model of a three-phase three-leg transformer is implemented for this study. Electromagnetic transient behavior exhibited in transformer voltages, currents and magnetic fluxes are computed and analyzed in time-domain. Simulations are performed for various voltage swell conditions with different magnitudes, starting and termination (recovery instant waveform) angles and durations. The impacts on the deterioration of power quality in input and output current and voltage waveforms are examined.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"8 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":"124340967","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.2011.6128949
José A. Barros, H. Leite
The question about how wind energy can be remunerated after the end of feed-in tariff schemes still remains unanswered in Portugal. Presently, the majority of wind energy promoters are connected through a point of common coupling, with a defined capacity attribution. In return, these promoters are rewarded with a premium rate (i.e., a feed-in tariff) for a limited amount of time or energy delivered. Therefore, promoters are foreseeing novel ways to return their investments and maximise their income, assuming feed-in tariff schemes will eventually come to a halt. This paper addresses the current Portuguese regulatory and commercial frameworks, especially the feed-in tariff mechanisms in force for supporting wind energy. The current level of revenues obtained by wind energy promoters in Portugal (provided by the feed-in tariff scheme) is compared with the hypothetical income they could obtain on a market environment. The non-firm access to the distribution networks is presented as a solution for integrating further generation capacity and thus increasing profitability for their promoters.
{"title":"Feed-in tariffs for wind energy in Portugal: Current status and prospective future","authors":"José A. Barros, H. Leite","doi":"10.1109/EPQU.2011.6128949","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128949","url":null,"abstract":"The question about how wind energy can be remunerated after the end of feed-in tariff schemes still remains unanswered in Portugal. Presently, the majority of wind energy promoters are connected through a point of common coupling, with a defined capacity attribution. In return, these promoters are rewarded with a premium rate (i.e., a feed-in tariff) for a limited amount of time or energy delivered. Therefore, promoters are foreseeing novel ways to return their investments and maximise their income, assuming feed-in tariff schemes will eventually come to a halt. This paper addresses the current Portuguese regulatory and commercial frameworks, especially the feed-in tariff mechanisms in force for supporting wind energy. The current level of revenues obtained by wind energy promoters in Portugal (provided by the feed-in tariff scheme) is compared with the hypothetical income they could obtain on a market environment. The non-firm access to the distribution networks is presented as a solution for integrating further generation capacity and thus increasing profitability for their promoters.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"2 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":"114861201","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.2011.6128841
Md. Junayed Sarker, R. A. Zaidi
Bringing sustainability in overall energy sphere can ensure a strong pathway for the existing economic growth of Nordic countries. Globally, Renewable Energy sources are taken into consideration to formulate a solid energy framework for envisioned carbon emission free world. This paper will convey some ideas on the technical and environomical viabilities of available renewable energy sources in Nordic countries. It will also focus on the concept of single power grid in Nordic zone based on competitive edge of the resources and technology. On economical front it will discuss financial feasibility of renewable energies without considering any positive bias through government subsidies and regulations.
{"title":"Sustainability of energy sources in nordic countries-case study based on comprehensive analysis of different renewable energy sources","authors":"Md. Junayed Sarker, R. A. Zaidi","doi":"10.1109/EPQU.2011.6128841","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128841","url":null,"abstract":"Bringing sustainability in overall energy sphere can ensure a strong pathway for the existing economic growth of Nordic countries. Globally, Renewable Energy sources are taken into consideration to formulate a solid energy framework for envisioned carbon emission free world. This paper will convey some ideas on the technical and environomical viabilities of available renewable energy sources in Nordic countries. It will also focus on the concept of single power grid in Nordic zone based on competitive edge of the resources and technology. On economical front it will discuss financial feasibility of renewable energies without considering any positive bias through government subsidies and regulations.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"37 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":"114389506","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.2011.6128860
S. Jahdi, Alidad Etemadian, L. Lai
Today, different newly developed methods and algorithm are provided that enable power system operators to have more suitable controls over systems' parameters. Even though these new methods have provided massive contributions over control of such parameters, but still having a full proper control over profile of voltages in distribution systems needs more developed advances. To meet these necessities, applications of DGs has been introduced. Although implementation of distribution generation units can benefit the system on aspects of better voltage profiles, but it may result in more complex control necessities on connected power system. In this paper, power flow on a radial 12 bus distribution system is done and results are analyzed based on different reactive compensation algorithms provided. Clearly the final goal is providing improvements in power loss reduction and enhancing the levels of voltage states on the system and this is unachievable unless a proper reactive compensation is added to active power provided to make a complete DG unit to enhance power system stability parameters. Simulation results show that if a proper level and type of reactive compensation is provided for distribution section of power systems connected to DG sources, voltage profiles can be improved and consequently reduction in power losses can be expected.
{"title":"Voltage profile stability analysis of radial distribution power systems in presence of DGs","authors":"S. Jahdi, Alidad Etemadian, L. Lai","doi":"10.1109/EPQU.2011.6128860","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128860","url":null,"abstract":"Today, different newly developed methods and algorithm are provided that enable power system operators to have more suitable controls over systems' parameters. Even though these new methods have provided massive contributions over control of such parameters, but still having a full proper control over profile of voltages in distribution systems needs more developed advances. To meet these necessities, applications of DGs has been introduced. Although implementation of distribution generation units can benefit the system on aspects of better voltage profiles, but it may result in more complex control necessities on connected power system. In this paper, power flow on a radial 12 bus distribution system is done and results are analyzed based on different reactive compensation algorithms provided. Clearly the final goal is providing improvements in power loss reduction and enhancing the levels of voltage states on the system and this is unachievable unless a proper reactive compensation is added to active power provided to make a complete DG unit to enhance power system stability parameters. Simulation results show that if a proper level and type of reactive compensation is provided for distribution section of power systems connected to DG sources, voltage profiles can be improved and consequently reduction in power losses can be expected.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"26 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":"124477921","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.2011.6128890
J. Pedroza, J. Toledo, W. Osal, C. Vásquez, F. Mendoza
Due to the importance of the hydroelectric project of 400 kV Tocoma for compliance with the requirements of demand, with high operational safety, we present the development of this work. Its objective consists in to analyze the behavior of the isolation of the transmission towers to the entrance of the bay of the substation due the impact of lightning on ground wire. We obtain the behavior of the line considering lightning of 5 and 20 kA and ground resistance at the foot of the tower of 0, 20, 100 and 400 Ω, using the simulation program PSCAD / EMTDC. The results show that none of the simulated cases are above the recommended level for line; however, to lightning of 20 kA and 400 Ω of resistance, the tension obtained of phase to ground is twice normal operation of the system, a value close to the limit let to the system.
{"title":"Simulation of the impact of lighting on the ground wire in 400 kV transmission lines","authors":"J. Pedroza, J. Toledo, W. Osal, C. Vásquez, F. Mendoza","doi":"10.1109/EPQU.2011.6128890","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128890","url":null,"abstract":"Due to the importance of the hydroelectric project of 400 kV Tocoma for compliance with the requirements of demand, with high operational safety, we present the development of this work. Its objective consists in to analyze the behavior of the isolation of the transmission towers to the entrance of the bay of the substation due the impact of lightning on ground wire. We obtain the behavior of the line considering lightning of 5 and 20 kA and ground resistance at the foot of the tower of 0, 20, 100 and 400 Ω, using the simulation program PSCAD / EMTDC. The results show that none of the simulated cases are above the recommended level for line; however, to lightning of 20 kA and 400 Ω of resistance, the tension obtained of phase to ground is twice normal operation of the system, a value close to the limit let to the system.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"163 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":"125974751","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.2011.6128909
B. Tomoiagă, M. Chindris, A. Sudriá-Andreu, A. Sumper
The optimization in the operation of distribution electric systems has become an acute problem. In order to evaluate some essential criteria (e.g., active power losses) the computation of power flow is absolutely necessary. Taking into account the real operating conditions (unbalance, harmonics) it is of great interest for accurate steady state estimation. The existent solutions proposed in literature are complex and it is difficult to implement them in unbalanced and harmonic polluted systems. By the original adaptation of the backward/forward sweep algorithm, the authors propose a novel paradigm to analyze the propagation of asymmetries and harmonic distortions through radial electric networks.
{"title":"Object oriented backward/forward algorithm for unbalanced and harmonic polluted distribution systems","authors":"B. Tomoiagă, M. Chindris, A. Sudriá-Andreu, A. Sumper","doi":"10.1109/EPQU.2011.6128909","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128909","url":null,"abstract":"The optimization in the operation of distribution electric systems has become an acute problem. In order to evaluate some essential criteria (e.g., active power losses) the computation of power flow is absolutely necessary. Taking into account the real operating conditions (unbalance, harmonics) it is of great interest for accurate steady state estimation. The existent solutions proposed in literature are complex and it is difficult to implement them in unbalanced and harmonic polluted systems. By the original adaptation of the backward/forward sweep algorithm, the authors propose a novel paradigm to analyze the propagation of asymmetries and harmonic distortions through radial electric networks.","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":"125981348","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.2011.6128863
C. Sourkounis, F. Einwachter
In the world wide discussion on reducing CO2 emissions, the utilization of electric vehicles is considered to be a reasonable approach. But an essential contribution to CO2 reduction can only be reached by integrating the vehicles into the electrical grid as controlled loads. Demand side management allows scheduling the charging process so that vehicle accumulators are charged during time periods of high regenerative power supply or low grid load. By this means the electric vehicles can be largely supplied by CO2 free energy sources and the utilization of the power supply infrastructure can be improved. Additional investment in the replacement reserve and the expansion of the grid transmission capacity can be avoided, especially in urban areas. This contribution will introduce different concepts for the integration of electric vehicles into the electrical grid, which allow a large utilization of stochastically fluctuating regenerative energy sources. Furthermore, incentive concepts for influencing the behavior of vehicle users, in order to create a temporal correlation between the charging time of the vehicle and the availability of power from regenerative sources, will be introduced and their effects discussed.
{"title":"Smart charge management of electric vehicles in decentralized power supply systems","authors":"C. Sourkounis, F. Einwachter","doi":"10.1109/EPQU.2011.6128863","DOIUrl":"https://doi.org/10.1109/EPQU.2011.6128863","url":null,"abstract":"In the world wide discussion on reducing CO2 emissions, the utilization of electric vehicles is considered to be a reasonable approach. But an essential contribution to CO2 reduction can only be reached by integrating the vehicles into the electrical grid as controlled loads. Demand side management allows scheduling the charging process so that vehicle accumulators are charged during time periods of high regenerative power supply or low grid load. By this means the electric vehicles can be largely supplied by CO2 free energy sources and the utilization of the power supply infrastructure can be improved. Additional investment in the replacement reserve and the expansion of the grid transmission capacity can be avoided, especially in urban areas. This contribution will introduce different concepts for the integration of electric vehicles into the electrical grid, which allow a large utilization of stochastically fluctuating regenerative energy sources. Furthermore, incentive concepts for influencing the behavior of vehicle users, in order to create a temporal correlation between the charging time of the vehicle and the availability of power from regenerative sources, will be introduced and their effects discussed.","PeriodicalId":369941,"journal":{"name":"11th International Conference on Electrical Power Quality and Utilisation","volume":"30 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":"127126193","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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