Pub Date : 2016-11-01DOI: 10.1109/PECON.2016.7951657
A. Fathy, O.M. El-baksawi
In this paper, a control strategy optimized by Mine Blast Algorithm (MBA) is applied on a variable speed wind generator (VSWG) system based on a doubly fed induction machine. The proposed MBA is applied to evaluate the optimal parameters of the current PI controller such that obtaining rotor current closes to the desired one; this purpose is achieved by minimizing the sum of squared error (SSE) between two currents. A direct closed loop control of stator current is taken place to regulate the reactive power of DFIG. The obtained results confirmed the efficiency of the proposed algorithm for determining the optimal gains of PI controller.
{"title":"PI controller parameters design of doubly fed induction generator based on Mine Blast Algorithm","authors":"A. Fathy, O.M. El-baksawi","doi":"10.1109/PECON.2016.7951657","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951657","url":null,"abstract":"In this paper, a control strategy optimized by Mine Blast Algorithm (MBA) is applied on a variable speed wind generator (VSWG) system based on a doubly fed induction machine. The proposed MBA is applied to evaluate the optimal parameters of the current PI controller such that obtaining rotor current closes to the desired one; this purpose is achieved by minimizing the sum of squared error (SSE) between two currents. A direct closed loop control of stator current is taken place to regulate the reactive power of DFIG. The obtained results confirmed the efficiency of the proposed algorithm for determining the optimal gains of PI controller.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116086244","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951633
R. Abd-Rahman, A. Haddad, M. S. Kamarudin, M. Yousof, N. Jamail
This paper proposes a dynamic pollution modelling for evaluating electric field distribution over the composite insulator surface. Axial-symmetric insulator profile under wet contaminated conditions was developed and analysed using Finite Element Method (FEM) software. A nonlinear field-dependent conductivity with simplified assumptions was established to characterise the electrical properties of the pollution layer. Comparative studies showed that simulation of the proposed pollution model results in a more realistic electric field profile, offering better understanding on how the electric field behaves under various wet and contaminated conditions.
{"title":"Dynamic modelling of polluted outdoor insulator under wet weather conditions","authors":"R. Abd-Rahman, A. Haddad, M. S. Kamarudin, M. Yousof, N. Jamail","doi":"10.1109/PECON.2016.7951633","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951633","url":null,"abstract":"This paper proposes a dynamic pollution modelling for evaluating electric field distribution over the composite insulator surface. Axial-symmetric insulator profile under wet contaminated conditions was developed and analysed using Finite Element Method (FEM) software. A nonlinear field-dependent conductivity with simplified assumptions was established to characterise the electrical properties of the pollution layer. Comparative studies showed that simulation of the proposed pollution model results in a more realistic electric field profile, offering better understanding on how the electric field behaves under various wet and contaminated conditions.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124683439","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951665
M. Norhisam, S. Umira, R. N. Firdaus, K. Yoshino, K. Maeda, T. Hanamoto
This paper presents a double-stator permanent magnet brushless DC machine (DS-PMBLDC) which is proposed to be used in light electric vehicles and to replace a typical motor for electric vehicles in future. However, to fulfill the limitation of motor performance at different conditions, electric vehicles require their own specific motor design. Thus, a modular type of motor which can easily replace the electrical motor based on requirements for the electric driving system in power train of an electric vehicle was proposed and discussed in this paper. The operating principle of the proposed machine is reported. Concentrated winding is adopted for the stators of a 9-slot 8-pole DS-PMBLDC machine. The cogging torque, back-EMF, air-gap flux density, torque and power characteristic have been analyzed using 2-dimensional Finite-Element Analysis (2D-FEA). Experimental and simulation results are compared and discussed. Theoretical analysis of the proposed machine show an efficiency of 80% and 75% efficiency in motoring and generating mode respectively. The 2D-FEA simulation results are in good agreement with the measurement results.
{"title":"Characteristic of double-stator PM machine for modular type power train in electric vehicles","authors":"M. Norhisam, S. Umira, R. N. Firdaus, K. Yoshino, K. Maeda, T. Hanamoto","doi":"10.1109/PECON.2016.7951665","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951665","url":null,"abstract":"This paper presents a double-stator permanent magnet brushless DC machine (DS-PMBLDC) which is proposed to be used in light electric vehicles and to replace a typical motor for electric vehicles in future. However, to fulfill the limitation of motor performance at different conditions, electric vehicles require their own specific motor design. Thus, a modular type of motor which can easily replace the electrical motor based on requirements for the electric driving system in power train of an electric vehicle was proposed and discussed in this paper. The operating principle of the proposed machine is reported. Concentrated winding is adopted for the stators of a 9-slot 8-pole DS-PMBLDC machine. The cogging torque, back-EMF, air-gap flux density, torque and power characteristic have been analyzed using 2-dimensional Finite-Element Analysis (2D-FEA). Experimental and simulation results are compared and discussed. Theoretical analysis of the proposed machine show an efficiency of 80% and 75% efficiency in motoring and generating mode respectively. The 2D-FEA simulation results are in good agreement with the measurement results.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126232101","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951630
M. Yousof, Shirllyana Riang, M. Uyup
Frequency Response Analysis (FRA) has been acknowledge as the most reliable and sensitive diagnostic tool to assess mechanical condition of power transformer. During assessing the integrity of transformer, proper and correct comparing interpretation of FRA response is become crucial. This paper presents and evaluates the influence of data size in statistical analysis when comparing the results of transformer frequency response. Three different statistical indicators are presented: the correlation coefficient (CC), the absolute sum of logarithmic error (ASLE) and the comparative standard deviation (CSD). The performance of these three selected statistical indicators while the data size varies is evaluated on simulated response. The same analysis is then repeated on frequency responses which were measured from an actual power transformer to test the validity of the earlier finding. In addition, the method of relative factor that proposed by the Chinese Standard DL 911/2004 is also evaluated and presented in this paper. Overall, this study concluded that the data size of the response does affect the statistical indicators. Recommendation is made that a standard data size is to be established and included in future FRA standard.
{"title":"The influence of data size in statistical analysis of power transformer frequency response","authors":"M. Yousof, Shirllyana Riang, M. Uyup","doi":"10.1109/PECON.2016.7951630","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951630","url":null,"abstract":"Frequency Response Analysis (FRA) has been acknowledge as the most reliable and sensitive diagnostic tool to assess mechanical condition of power transformer. During assessing the integrity of transformer, proper and correct comparing interpretation of FRA response is become crucial. This paper presents and evaluates the influence of data size in statistical analysis when comparing the results of transformer frequency response. Three different statistical indicators are presented: the correlation coefficient (CC), the absolute sum of logarithmic error (ASLE) and the comparative standard deviation (CSD). The performance of these three selected statistical indicators while the data size varies is evaluated on simulated response. The same analysis is then repeated on frequency responses which were measured from an actual power transformer to test the validity of the earlier finding. In addition, the method of relative factor that proposed by the Chinese Standard DL 911/2004 is also evaluated and presented in this paper. Overall, this study concluded that the data size of the response does affect the statistical indicators. Recommendation is made that a standard data size is to be established and included in future FRA standard.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132449017","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951582
M. F. Noorizan, M. Kamarol, M. Mariatti
Silicone rubber (SiR) is a common polymeric material that has been used as solid insulation in cable especially for end termination and two cables connection insulation. However, cable insulator is easily exposed to moisture if the cable is defected after installation. This causing water tree to be produced whenever high voltage is applied. Water tree development worsens when there is micro protrusions exist at the conductor's surface. An experiment is developed in order to observe the relation between water tree and micro protrusion and their effect toward insulation material. This experimental development has prepared two types of sample testing which are sharp and blunt needles. These sharp and blunt needless are referred to the micro protrusion appear on the conductor's surface. Furthermore, the needle is exposed to salt solution that acts as a moisture contaminant. The samples have been applied high voltage stress at 10kV. As a result, water tree development with different shape and length has been observed on both samples. The tip shape of the needle influenced the development of the water tree. The sample of sharp needle tip precede in water tree formation because it produces stronger and larger area of electrical field.
{"title":"Investigation of water treeing development in silicone rubber under sharp and blunt needles","authors":"M. F. Noorizan, M. Kamarol, M. Mariatti","doi":"10.1109/PECON.2016.7951582","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951582","url":null,"abstract":"Silicone rubber (SiR) is a common polymeric material that has been used as solid insulation in cable especially for end termination and two cables connection insulation. However, cable insulator is easily exposed to moisture if the cable is defected after installation. This causing water tree to be produced whenever high voltage is applied. Water tree development worsens when there is micro protrusions exist at the conductor's surface. An experiment is developed in order to observe the relation between water tree and micro protrusion and their effect toward insulation material. This experimental development has prepared two types of sample testing which are sharp and blunt needles. These sharp and blunt needless are referred to the micro protrusion appear on the conductor's surface. Furthermore, the needle is exposed to salt solution that acts as a moisture contaminant. The samples have been applied high voltage stress at 10kV. As a result, water tree development with different shape and length has been observed on both samples. The tip shape of the needle influenced the development of the water tree. The sample of sharp needle tip precede in water tree formation because it produces stronger and larger area of electrical field.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132685455","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951564
Seyed Javad Mirazimiabarghouei, T. Ahfock, A. Helwig
Single Wire Earth Return (SWER) systems with long transmission line were introduced as one of the low cost options for remote electrification. Long transmission lines and load growth in such a system make voltage regulation a concern. Four quadrants distribution STATic COMpensators (DSTATCOMs) as voltage support equipment in SWER system with ability of injecting or absorbing active and reactive power is proposed. In this paper, the operation of DSTATCOMs in terms of voltage support effectiveness is studied. Particularly, the focus is on DSTATCOM Optimum Operation Point (DOOP) to have the maximum possible support during heavy load. A SWER system is developed, using MATLAB, to study the effect of DSTATCOM operation point on the system voltage profile.
{"title":"Single Wire Earth Return (SWER) system voltage support using four quadrant DSTATCOM","authors":"Seyed Javad Mirazimiabarghouei, T. Ahfock, A. Helwig","doi":"10.1109/PECON.2016.7951564","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951564","url":null,"abstract":"Single Wire Earth Return (SWER) systems with long transmission line were introduced as one of the low cost options for remote electrification. Long transmission lines and load growth in such a system make voltage regulation a concern. Four quadrants distribution STATic COMpensators (DSTATCOMs) as voltage support equipment in SWER system with ability of injecting or absorbing active and reactive power is proposed. In this paper, the operation of DSTATCOMs in terms of voltage support effectiveness is studied. Particularly, the focus is on DSTATCOM Optimum Operation Point (DOOP) to have the maximum possible support during heavy load. A SWER system is developed, using MATLAB, to study the effect of DSTATCOM operation point on the system voltage profile.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132959450","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951611
A. M. Razali, Norazelina Kamisman, J. M. Lazi, N. Bahari, W. A. Halim
This paper presents the solution for odd and even number of switching angles of harmonic elimination pulse width modulation (HEPWM). HEPWM capable to eliminate low order harmonics of inverter output voltage by solving the transcendental equation of the switching angles. The optimum switching angles are calculated using differential evolution (DE) algorithm. DE is simple and effective algorithm. The calculated switching angles applied to the three-phase voltage source inverter (VSI) and harmonic performance of output voltage are examined using MATLAB/Simulink software. The Total harmonic Distortion (THD) of line to neutral of inverter is analyzed for different number of switching angles. The simulation result showed that the low order harmonics, namely 5th, 7th, 11th, 13th, 17th, 19th, 23th was eliminated individually by N=3,4,5,6,7 and 8.
{"title":"Differential evolution technique in solving HEPWM switching angles of three-phase voltage source inverter","authors":"A. M. Razali, Norazelina Kamisman, J. M. Lazi, N. Bahari, W. A. Halim","doi":"10.1109/PECON.2016.7951611","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951611","url":null,"abstract":"This paper presents the solution for odd and even number of switching angles of harmonic elimination pulse width modulation (HEPWM). HEPWM capable to eliminate low order harmonics of inverter output voltage by solving the transcendental equation of the switching angles. The optimum switching angles are calculated using differential evolution (DE) algorithm. DE is simple and effective algorithm. The calculated switching angles applied to the three-phase voltage source inverter (VSI) and harmonic performance of output voltage are examined using MATLAB/Simulink software. The Total harmonic Distortion (THD) of line to neutral of inverter is analyzed for different number of switching angles. The simulation result showed that the low order harmonics, namely 5th, 7th, 11th, 13th, 17th, 19th, 23th was eliminated individually by N=3,4,5,6,7 and 8.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132329430","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951550
N. Azahan, J. J. Jamian, Z. A. Noorden
Electric vehicle (EV) had the potential for helping to create a more sustainable future as it powered by green technology battery. Therefore, the investigation on battery performance has gained a lot of attention since it is one of advanced technology storage element. This paper reviews an analysis of the relationship between the acceleration of electric vehicles and state-of-charging (SOC) of battery in EV. The energy storage capacity reduction in the battery is inversely proportional to the acceleration rate. As the driving cycles and acceleration rate changing will influence the time taken for the battery to reach 0% of SOC. Several random driving cycles are created in order to identify its relationship with SOC. At the end of this paper, a mathematical equation is introduced to represent the relationship between acceleration rates versus SOC of EV.
{"title":"Analysis of relationship between acceleration and battery state-of-charging in electric vehicle","authors":"N. Azahan, J. J. Jamian, Z. A. Noorden","doi":"10.1109/PECON.2016.7951550","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951550","url":null,"abstract":"Electric vehicle (EV) had the potential for helping to create a more sustainable future as it powered by green technology battery. Therefore, the investigation on battery performance has gained a lot of attention since it is one of advanced technology storage element. This paper reviews an analysis of the relationship between the acceleration of electric vehicles and state-of-charging (SOC) of battery in EV. The energy storage capacity reduction in the battery is inversely proportional to the acceleration rate. As the driving cycles and acceleration rate changing will influence the time taken for the battery to reach 0% of SOC. Several random driving cycles are created in order to identify its relationship with SOC. At the end of this paper, a mathematical equation is introduced to represent the relationship between acceleration rates versus SOC of EV.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129293191","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951544
A. N. Syafawati, Teng-Way Tsai, Yaow-Ming Chen, Y. Lee, T. Chang
This paper presents a flexible active power line conditioner (FAPLC) that works for reactive power or harmonic current compensation with load balancing and single-phase sag compensation as its additional functions. It injects single-phase current to heavy-load phase and draw currents from other two light-load phases for unbalanced loads condition. In type B fault, it only injects required reactive power to sag phase without affecting other phases. Furthermore, FAPLC provides an active power compensation without the need of power source. The operation principle and control method of FAPLC are discussed. Simulation results are present via Simulink's to validate the operation of FAPLC system.
{"title":"Flexible three-phase active power line conditioner","authors":"A. N. Syafawati, Teng-Way Tsai, Yaow-Ming Chen, Y. Lee, T. Chang","doi":"10.1109/PECON.2016.7951544","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951544","url":null,"abstract":"This paper presents a flexible active power line conditioner (FAPLC) that works for reactive power or harmonic current compensation with load balancing and single-phase sag compensation as its additional functions. It injects single-phase current to heavy-load phase and draw currents from other two light-load phases for unbalanced loads condition. In type B fault, it only injects required reactive power to sag phase without affecting other phases. Furthermore, FAPLC provides an active power compensation without the need of power source. The operation principle and control method of FAPLC are discussed. Simulation results are present via Simulink's to validate the operation of FAPLC system.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"330 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116355661","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 : 2016-11-01DOI: 10.1109/PECON.2016.7951632
Z. Zarim, Ir A. Basri A. Ghani
In Malaysia, since 2007, had practice insulation resistance measurement for underground cable in particular dielectric absorption ratio (DAR). This ratio / index have been used as screening test to diagnose the health condition of the underground cable. If the ratio / index shows low, advance test such as Dielectric Spectroscopy or Partial Discharge will be perform on the cable. The determination of the cable condition was solely based on the Insulation Resistance equipment manufacturer recommendation. Therefore in this study, the effectiveness of the index / ratio to determine the condition of the cable will be reviewed.
{"title":"The effect of water tree and partial discharge defects in XLPE cables to the dielectric absorption ratio","authors":"Z. Zarim, Ir A. Basri A. Ghani","doi":"10.1109/PECON.2016.7951632","DOIUrl":"https://doi.org/10.1109/PECON.2016.7951632","url":null,"abstract":"In Malaysia, since 2007, had practice insulation resistance measurement for underground cable in particular dielectric absorption ratio (DAR). This ratio / index have been used as screening test to diagnose the health condition of the underground cable. If the ratio / index shows low, advance test such as Dielectric Spectroscopy or Partial Discharge will be perform on the cable. The determination of the cable condition was solely based on the Insulation Resistance equipment manufacturer recommendation. Therefore in this study, the effectiveness of the index / ratio to determine the condition of the cable will be reviewed.","PeriodicalId":259969,"journal":{"name":"2016 IEEE International Conference on Power and Energy (PECon)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117028237","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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