Pub Date : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356862
Jin-a Kim, Jaehee Lee, Sung-Kwan Joo
This paper presents a risk assessment method to measure the Conditional Value at Risk (CVaR) of a transmission expansion project using the Cross-Entropy (CE) method. In the transmission investment, there are various uncertainties such as demand, fuel costs and electricity prices. These uncertain factors can influence the future cash flow of a transmission expansion project and become risk factors for an investor. The CVaR can be used to give an investor an accurate indication of the potential losses for the transmission investment. However, the use of the Crude Monte Carlo (CMC) method in CVaR calculation requires a large computational effort to obtain reliable results. In this paper, the CE method is applied to reduce the computational effort in the CVaR calculation. A numerical example is presented to illustrate the effectiveness of the proposed CE-based CVaR method.
{"title":"Assessment of Conditional Value at Risk (CVaR) in transmission investment using Cross Entropy method","authors":"Jin-a Kim, Jaehee Lee, Sung-Kwan Joo","doi":"10.1109/TD-ASIA.2009.5356862","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356862","url":null,"abstract":"This paper presents a risk assessment method to measure the Conditional Value at Risk (CVaR) of a transmission expansion project using the Cross-Entropy (CE) method. In the transmission investment, there are various uncertainties such as demand, fuel costs and electricity prices. These uncertain factors can influence the future cash flow of a transmission expansion project and become risk factors for an investor. The CVaR can be used to give an investor an accurate indication of the potential losses for the transmission investment. However, the use of the Crude Monte Carlo (CMC) method in CVaR calculation requires a large computational effort to obtain reliable results. In this paper, the CE method is applied to reduce the computational effort in the CVaR calculation. A numerical example is presented to illustrate the effectiveness of the proposed CE-based CVaR method.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114182393","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356825
Jiyoung Song, Kyebyung Lee, Hansang Lee, G. Jang, Sae-Hyuk Kwon, Hanmin Lee, Changmu Lee, Gildong Kim
As the importance of the improvement of energy efficiency is constantly increasing, a study has been done on the implementation of an energy storage system, to improve load efficiency, on the railway which has relatively large regenerative energy. The pre-existing regenerative energy not only has a low efficiency but also increases the catenary, which has a possibility to create problems in the electrical device voltage, during the regeneration process. In this paper, the improvement of the efficiency and stabilization of the catenary voltage by the implementation of an energy storage device is being discussed. The composition of the interface, control strategy and reduced railway model for simulation are being proposed.
{"title":"Interface composition and reduced railway model to verify the effect of supercapacitor applied to railway system","authors":"Jiyoung Song, Kyebyung Lee, Hansang Lee, G. Jang, Sae-Hyuk Kwon, Hanmin Lee, Changmu Lee, Gildong Kim","doi":"10.1109/TD-ASIA.2009.5356825","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356825","url":null,"abstract":"As the importance of the improvement of energy efficiency is constantly increasing, a study has been done on the implementation of an energy storage system, to improve load efficiency, on the railway which has relatively large regenerative energy. The pre-existing regenerative energy not only has a low efficiency but also increases the catenary, which has a possibility to create problems in the electrical device voltage, during the regeneration process. In this paper, the improvement of the efficiency and stabilization of the catenary voltage by the implementation of an energy storage device is being discussed. The composition of the interface, control strategy and reduced railway model for simulation are being proposed.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114487536","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356917
hee-myung jeong, Hwa-Seok Lee, Juneho Park
In power system operations, state estimation plays an important role in security control. For the state estimation problem, the weighted least squares (WLS) method is widely used at present. However, these algorithms can converge to local optimal solutions. Recently, modern heuristic optimization methods such as Particle Swarm Optimization (PSO) have been introduced to overcome the disadvantage of the classical optimization problem. However, heuristic optimization methods based on populations require a lengthy computing time to find an optimal solution. In this paper, we used particle swarm optimization (PSO) to search for the optimal solution of state estimation in power systems. To overcome the shortcoming of heuristic optimization methods, we proposed parallel processing of the PSO algorithm based on the PC cluster system. The proposed approach was tested with the IEEE-118 bus systems. From the simulation results, we found that the parallel PSO based on the PC cluster system can be applicable for power system state estimation.
{"title":"Application of parallel particle swarm optimization on power system state estimation","authors":"hee-myung jeong, Hwa-Seok Lee, Juneho Park","doi":"10.1109/TD-ASIA.2009.5356917","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356917","url":null,"abstract":"In power system operations, state estimation plays an important role in security control. For the state estimation problem, the weighted least squares (WLS) method is widely used at present. However, these algorithms can converge to local optimal solutions. Recently, modern heuristic optimization methods such as Particle Swarm Optimization (PSO) have been introduced to overcome the disadvantage of the classical optimization problem. However, heuristic optimization methods based on populations require a lengthy computing time to find an optimal solution. In this paper, we used particle swarm optimization (PSO) to search for the optimal solution of state estimation in power systems. To overcome the shortcoming of heuristic optimization methods, we proposed parallel processing of the PSO algorithm based on the PC cluster system. The proposed approach was tested with the IEEE-118 bus systems. From the simulation results, we found that the parallel PSO based on the PC cluster system can be applicable for power system state estimation.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114852032","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356816
Jeonje Park, Wu Liang, Jaeseok Choi, A. El-Keib, Mohammad Shahidehpour
This paper proposes a method for choosing the best transmission system expansion plan(TSEP) using nodal/bus delivery marginal rate criterion (BMRk) defined newly in this paper. The objective method minimizes a total cost which is an investment budget for constructing new transmission lines subject to the BMRk which means a nodal deterministic reliability level requirement at specified load point. Test results on an existing 21-bus system are included in the paper. It demonstrated the suitability of the proposed method for solving the TSEPproblem in competitive electricity market environment.
{"title":"Transmission system expansion planning by nodal delivery marginal rate criterion","authors":"Jeonje Park, Wu Liang, Jaeseok Choi, A. El-Keib, Mohammad Shahidehpour","doi":"10.1109/TD-ASIA.2009.5356816","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356816","url":null,"abstract":"This paper proposes a method for choosing the best transmission system expansion plan(TSEP) using nodal/bus delivery marginal rate criterion (BMRk) defined newly in this paper. The objective method minimizes a total cost which is an investment budget for constructing new transmission lines subject to the BMRk which means a nodal deterministic reliability level requirement at specified load point. Test results on an existing 21-bus system are included in the paper. It demonstrated the suitability of the proposed method for solving the TSEPproblem in competitive electricity market environment.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115107390","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356950
Peng Gao, Libao Shi, L. Yao, Y. Ni, M. Bazargan
How to identify the weak buses comprehensively and practically in power system voltage stability analysis is an important issue, and is posing great interests to the power engineers. In this paper, a multi-criteria integrated voltage stability index was proposed for weak buses identification. Firstly, the bus voltage change index and reactive power margins, which were determined by P-V curve and Q-V curve, respectively, were employed to form the required data set involving the corresponding bus voltage margin and reactive power margin information. An overall and practical evaluation method called as ideal point method was then proposed to integrate the two aforementioned voltage stability indices with certain weight. By tuning the corresponding weight coefficients, the decision-making reflecting the preference of power engineer could be made. Finally the case studies on the 10-machine 39-bus New England test system as benchmark were carried out to demonstrate the validity and effectiveness of the proposed method.
{"title":"Multi-criteria integrated voltage stability index for weak buses identification","authors":"Peng Gao, Libao Shi, L. Yao, Y. Ni, M. Bazargan","doi":"10.1109/TD-ASIA.2009.5356950","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356950","url":null,"abstract":"How to identify the weak buses comprehensively and practically in power system voltage stability analysis is an important issue, and is posing great interests to the power engineers. In this paper, a multi-criteria integrated voltage stability index was proposed for weak buses identification. Firstly, the bus voltage change index and reactive power margins, which were determined by P-V curve and Q-V curve, respectively, were employed to form the required data set involving the corresponding bus voltage margin and reactive power margin information. An overall and practical evaluation method called as ideal point method was then proposed to integrate the two aforementioned voltage stability indices with certain weight. By tuning the corresponding weight coefficients, the decision-making reflecting the preference of power engineer could be made. Finally the case studies on the 10-machine 39-bus New England test system as benchmark were carried out to demonstrate the validity and effectiveness of the proposed method.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124697444","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356976
M. Aoki, Yuta Kobayashi, Hiroshi Kobayashi, F. Ueda
In recent years, the voltage rise at the end of distribution line and the increase of harmonic voltages has become to be greatly concerned because of extreme expansion of distributed generation (DG) systems and excessive amount of static capacitors (SCs) for improving power factor. For compensating leading current and harmonic currents from consumers, the hybrid type of power quality conditioner was proposed. The proposed system consists of a LC series circuit, a series transformer and a self-commutated converter in order to reduce the capacity of the converter than the conventional type of static synchronous compensators (STATCOMs) and active filters (AFs). This paper presents SC bank quantity control to expand the range of the compensating current and DC bus voltage control of the converter in the hybrid type power quality conditioner. In this study, the performance evaluations for the proposed conditioner in terms of the control of the harmful currents are presented by the various simulations.
{"title":"Static capacitor control for hybrid type power quality conditioner","authors":"M. Aoki, Yuta Kobayashi, Hiroshi Kobayashi, F. Ueda","doi":"10.1109/TD-ASIA.2009.5356976","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356976","url":null,"abstract":"In recent years, the voltage rise at the end of distribution line and the increase of harmonic voltages has become to be greatly concerned because of extreme expansion of distributed generation (DG) systems and excessive amount of static capacitors (SCs) for improving power factor. For compensating leading current and harmonic currents from consumers, the hybrid type of power quality conditioner was proposed. The proposed system consists of a LC series circuit, a series transformer and a self-commutated converter in order to reduce the capacity of the converter than the conventional type of static synchronous compensators (STATCOMs) and active filters (AFs). This paper presents SC bank quantity control to expand the range of the compensating current and DC bus voltage control of the converter in the hybrid type power quality conditioner. In this study, the performance evaluations for the proposed conditioner in terms of the control of the harmful currents are presented by the various simulations.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124905656","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356997
Lucheng Hong, Libao Shi, L. Yao, Y. Ni, M. Bazargan
In this paper, the probability theory and fuzzy sets theory were employed to carry out the studies on power system load flow analysis with consideration of wind generation uncertainties. Based on the Possibility/Probability Consistency Principle, the original measurement based wind speed probability density distribution was transformed to the wind speed possibility distribution firstly. The fuzzy model of power output from squirrel cage induction generator (SCIG) was then built in accordance with a simplified power-speed curve of SCIG. The proposed fuzzy model was linearized further for simplicity. And the sensitivity analysis based method was employed to carry out and obtain the possibility distribution of fuzzy load flow solutions. The modified IEEE 14-bus system was used as benchmark to carry out the case studies. Numerical results have demonstrated the validity and effectiveness of the proposed model and method.
{"title":"Study on fuzzy load flow with consideration of wind generation uncertainties","authors":"Lucheng Hong, Libao Shi, L. Yao, Y. Ni, M. Bazargan","doi":"10.1109/TD-ASIA.2009.5356997","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356997","url":null,"abstract":"In this paper, the probability theory and fuzzy sets theory were employed to carry out the studies on power system load flow analysis with consideration of wind generation uncertainties. Based on the Possibility/Probability Consistency Principle, the original measurement based wind speed probability density distribution was transformed to the wind speed possibility distribution firstly. The fuzzy model of power output from squirrel cage induction generator (SCIG) was then built in accordance with a simplified power-speed curve of SCIG. The proposed fuzzy model was linearized further for simplicity. And the sensitivity analysis based method was employed to carry out and obtain the possibility distribution of fuzzy load flow solutions. The modified IEEE 14-bus system was used as benchmark to carry out the case studies. Numerical results have demonstrated the validity and effectiveness of the proposed model and method.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122946595","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356958
G. Lee, S. Hwang, H. C. Lee
Recently, high temperature superconducting power cable (HTS power cable) is seriously taking attention to solve transmission line congestion problem of high electricity density urban area. However, HTS cable has different current-resistance characteristics-quench- compare to conventional copper cable, and it makes the protection and control of HTS cable more difficult. This paper suggests cooperative fault current control method to protect HTS cable. The cable model is composed of superconductor, shield, and former part. To examine the characteristics of HTS cable, coordination with SFCL (Superconducting Fault Current Limiter) is introduced. According to the simulation result, HTS cable wasn't protected by OCR (Over current relay) before SFCL was set up, whereas it was protected to set SFCL. Various countermeasure to decrease fault current, including SFCL, is necessary to operate HTS cable system securely.
{"title":"A study on cooperative control method in HTS cable under parallel power system","authors":"G. Lee, S. Hwang, H. C. Lee","doi":"10.1109/TD-ASIA.2009.5356958","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356958","url":null,"abstract":"Recently, high temperature superconducting power cable (HTS power cable) is seriously taking attention to solve transmission line congestion problem of high electricity density urban area. However, HTS cable has different current-resistance characteristics-quench- compare to conventional copper cable, and it makes the protection and control of HTS cable more difficult. This paper suggests cooperative fault current control method to protect HTS cable. The cable model is composed of superconductor, shield, and former part. To examine the characteristics of HTS cable, coordination with SFCL (Superconducting Fault Current Limiter) is introduced. According to the simulation result, HTS cable wasn't protected by OCR (Over current relay) before SFCL was set up, whereas it was protected to set SFCL. Various countermeasure to decrease fault current, including SFCL, is necessary to operate HTS cable system securely.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123921683","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356883
Chanhyeok Kim, Hyeonseok Park, Seong-ho Ji, D. Rho
Recently, new dispersed power sources such as photovoltaic, wind power, fuel cell etc. are energetically interconnected and operated in the distribution systems, as one of the national projects for alternative energy. The technical guidelines on the interconnection of dispersed power sources have been established and conducted positively. However, protection devices (Re-closer) in primary feeder of distribution system interconnected with dispersed power sources like photovoltaic generation systems may cause problems of malfunction, and then many customers could have problems like an interruption. So, this paper presents the optimal method to minimize the impact of interruption, using MATLAB /SIMULINK. And, also this paper shows the effectiveness of proposed method by simulating at the field distribution systems.
{"title":"Analysis for the mal-function of protective devices (Re-closer) at the primary feeders with dispersed power sources","authors":"Chanhyeok Kim, Hyeonseok Park, Seong-ho Ji, D. Rho","doi":"10.1109/TD-ASIA.2009.5356883","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356883","url":null,"abstract":"Recently, new dispersed power sources such as photovoltaic, wind power, fuel cell etc. are energetically interconnected and operated in the distribution systems, as one of the national projects for alternative energy. The technical guidelines on the interconnection of dispersed power sources have been established and conducted positively. However, protection devices (Re-closer) in primary feeder of distribution system interconnected with dispersed power sources like photovoltaic generation systems may cause problems of malfunction, and then many customers could have problems like an interruption. So, this paper presents the optimal method to minimize the impact of interruption, using MATLAB /SIMULINK. And, also this paper shows the effectiveness of proposed method by simulating at the field distribution systems.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125331530","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 : 2009-12-18DOI: 10.1109/TD-ASIA.2009.5356902
Z. Vale, C. Ramos, H. Morais, P. Faria, Marco Silva
Power systems are planed and operated according to the optimization of the available resources. Traditionally these tasks were mostly undertaken in a centralized way which is no longer adequate in a competitive environment. Demand response can play a very relevant role in this context but adequate tools to negotiate this kind of resources are required. This paper presents an approach to deal with these issues, by using a multi-agent simulator able to model demand side players and simulate their strategic behavior. The paper includes an illustrative case study that considers an incident situation. The distribution company is able to reduce load curtailment due to load flexibility contracts previously established with demand side players.
{"title":"The role of demand response in future power systems","authors":"Z. Vale, C. Ramos, H. Morais, P. Faria, Marco Silva","doi":"10.1109/TD-ASIA.2009.5356902","DOIUrl":"https://doi.org/10.1109/TD-ASIA.2009.5356902","url":null,"abstract":"Power systems are planed and operated according to the optimization of the available resources. Traditionally these tasks were mostly undertaken in a centralized way which is no longer adequate in a competitive environment. Demand response can play a very relevant role in this context but adequate tools to negotiate this kind of resources are required. This paper presents an approach to deal with these issues, by using a multi-agent simulator able to model demand side players and simulate their strategic behavior. The paper includes an illustrative case study that considers an incident situation. The distribution company is able to reduce load curtailment due to load flexibility contracts previously established with demand side players.","PeriodicalId":131589,"journal":{"name":"2009 Transmission & Distribution Conference & Exposition: Asia and Pacific","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125687605","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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