Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077280
Jatin Verma, I. Sharieff, Ranjana Sodhi
Contingency analysis plays a key role in evaluating the performance of a system under stressed conditions. This paper proposes Trajectory Violation Integral (TVI) index as a measure to quantify the effect of contingency. Contingency clustering enables partitioning of the system into coherent and independent Voltage Control Areas. The data that is worked on during contingency clustering is of high dimensional nature and studies have shown that the algorithms that work on lower dimensional data may get impaired while handling higher dimensional data due to various reasons, one of them being the curse of dimensionality. This work emphasizes the problems associated while dealing with higher dimensional data and proposes a meticulous strategy to undermine the effects of higher dimensionality in the premises of contingency clustering for the formation of Dynamic Voltage Control Areas.
{"title":"A meticulous approach towards contingency clustering in power system","authors":"Jatin Verma, I. Sharieff, Ranjana Sodhi","doi":"10.1109/POWERI.2016.8077280","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077280","url":null,"abstract":"Contingency analysis plays a key role in evaluating the performance of a system under stressed conditions. This paper proposes Trajectory Violation Integral (TVI) index as a measure to quantify the effect of contingency. Contingency clustering enables partitioning of the system into coherent and independent Voltage Control Areas. The data that is worked on during contingency clustering is of high dimensional nature and studies have shown that the algorithms that work on lower dimensional data may get impaired while handling higher dimensional data due to various reasons, one of them being the curse of dimensionality. This work emphasizes the problems associated while dealing with higher dimensional data and proposes a meticulous strategy to undermine the effects of higher dimensionality in the premises of contingency clustering for the formation of Dynamic Voltage Control Areas.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"11 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":"134190997","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/POWERI.2016.8077459
D. Jain, U. Kalla
This paper is aimed at modeling, control and analysis of Solar PV-Grid integration system using Anti-Hebbian control algorithm. The inverter performs multiple functions such as transferring real power produced by PV into the grid, fundamental and harmonic reactive power compensation, real power compensation, power factor correction and voltage regulation. The under mentioned simulation results and mathematical model validate the proposed system. The proposed system shows satisfactory performance in steady state and dynamic loading conditions under varying insolation levels.
{"title":"Anti-hebbian control algorithm for three-phase inverter in grid connected solar PV system","authors":"D. Jain, U. Kalla","doi":"10.1109/POWERI.2016.8077459","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077459","url":null,"abstract":"This paper is aimed at modeling, control and analysis of Solar PV-Grid integration system using Anti-Hebbian control algorithm. The inverter performs multiple functions such as transferring real power produced by PV into the grid, fundamental and harmonic reactive power compensation, real power compensation, power factor correction and voltage regulation. The under mentioned simulation results and mathematical model validate the proposed system. The proposed system shows satisfactory performance in steady state and dynamic loading conditions under varying insolation levels.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"22 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":"134485699","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/POWERI.2016.8077312
U. Kalla, Avanti Verma, Bhim Singh, Keshav Joshi
The multilevel inverter technology has gained a tremendous significance in the research area. This paper proposed a new controller for generating the switching sequence of power devices used in multilevel inverter to produce the desired output. An embedded code has been developed to control the switching states of different IGBT switches. To validate the effectiveness of the proposed technique to control the multilevel inverter switching states MATLAB simulation of 3-level, 5-level and 17-level using cascaded H bridge topology of multi-level inverter is presented in this paper. Each multilevel inverter configuration presented in this paper is explained by the corresponding schematic diagram, operating principle, and simulation results
{"title":"A controller for cascaded h-bridge multilevel inverter","authors":"U. Kalla, Avanti Verma, Bhim Singh, Keshav Joshi","doi":"10.1109/POWERI.2016.8077312","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077312","url":null,"abstract":"The multilevel inverter technology has gained a tremendous significance in the research area. This paper proposed a new controller for generating the switching sequence of power devices used in multilevel inverter to produce the desired output. An embedded code has been developed to control the switching states of different IGBT switches. To validate the effectiveness of the proposed technique to control the multilevel inverter switching states MATLAB simulation of 3-level, 5-level and 17-level using cascaded H bridge topology of multi-level inverter is presented in this paper. Each multilevel inverter configuration presented in this paper is explained by the corresponding schematic diagram, operating principle, and simulation results","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"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":"134555570","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/POWERI.2016.8077211
A. K. Gupta, P. Samuel, Deepak Kumar
Inductors and diodes in combination with active switches are the basic building blocks of dc-dc converters. When the active switches are gated on then inductors are charged in series and when the switch is off, inductors are discharged in parallel. The principle of these switched inductor topologies are basic building blocks of impedance network topologies. In these topologies, the inverter zero state switching stage is used to make the inductor charged and discharged. Thus a unique impedance network is designed to boost the output. The Z-source inverter is an example of such type of topologies. The impedance network of Z-source inverter is designed to couple the inverter main circuit to input power source. But it has limitations of high voltage stress across the switches. Over the years, numerous other topologies such as quasi-Z-source inverter, improved Z-Source Inverter etc. have been implemented to improve limitations of Z-source inverter and to make it more suitable for the renewable energy applications. This review presents the comparisons of impedance network topologies on their basic structural differences, advantages and limitations along with dc link voltages and boost factor. MATLAB/Simulink is chosen for verification of the analysis made.
{"title":"A state of art review and challenges with impedance networks topologies","authors":"A. K. Gupta, P. Samuel, Deepak Kumar","doi":"10.1109/POWERI.2016.8077211","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077211","url":null,"abstract":"Inductors and diodes in combination with active switches are the basic building blocks of dc-dc converters. When the active switches are gated on then inductors are charged in series and when the switch is off, inductors are discharged in parallel. The principle of these switched inductor topologies are basic building blocks of impedance network topologies. In these topologies, the inverter zero state switching stage is used to make the inductor charged and discharged. Thus a unique impedance network is designed to boost the output. The Z-source inverter is an example of such type of topologies. The impedance network of Z-source inverter is designed to couple the inverter main circuit to input power source. But it has limitations of high voltage stress across the switches. Over the years, numerous other topologies such as quasi-Z-source inverter, improved Z-Source Inverter etc. have been implemented to improve limitations of Z-source inverter and to make it more suitable for the renewable energy applications. This review presents the comparisons of impedance network topologies on their basic structural differences, advantages and limitations along with dc link voltages and boost factor. MATLAB/Simulink is chosen for verification of the analysis made.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"23 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":"131979497","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/POWERI.2016.8077293
Priyank Shah, Ikhlaq Hussain, Bhim Singh
This paper deals with a solar energy conversion system (SECS) interfaced with three phase grid using a fourth order generalized integrator quadrature signal generator (FOGI-QSG)based control algorithm, which helps to mitigate the power quality problems like power factor correction, load balancing, harmonics elimination and noise cancellation. The perturb and observe (P&O) based maximum power tracking point (MPPT) algorithm is used to extract the maximum power from solar photovoltaic (SPV) array. The reference voltage is obtained from MPPT algorithm which helps to maintain DC link voltage of a voltage source converter (VSC). The FOGI-QSG based control algorithm is an easily realizable without compromising accuracy. The control algorithm is validated experimentally on developed hardware in the laboratory. Total harmonic distortion of source current of distribution network has been found within limit according to an IEEE-519 standard at common coupling point.
{"title":"FOGI-QSG based control of multifunctional grid tied SECS","authors":"Priyank Shah, Ikhlaq Hussain, Bhim Singh","doi":"10.1109/POWERI.2016.8077293","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077293","url":null,"abstract":"This paper deals with a solar energy conversion system (SECS) interfaced with three phase grid using a fourth order generalized integrator quadrature signal generator (FOGI-QSG)based control algorithm, which helps to mitigate the power quality problems like power factor correction, load balancing, harmonics elimination and noise cancellation. The perturb and observe (P&O) based maximum power tracking point (MPPT) algorithm is used to extract the maximum power from solar photovoltaic (SPV) array. The reference voltage is obtained from MPPT algorithm which helps to maintain DC link voltage of a voltage source converter (VSC). The FOGI-QSG based control algorithm is an easily realizable without compromising accuracy. The control algorithm is validated experimentally on developed hardware in the laboratory. Total harmonic distortion of source current of distribution network has been found within limit according to an IEEE-519 standard at common coupling point.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"40 5 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":"133921134","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/POWERI.2016.8077320
Piyush Kant, Bhim Singh
This paper proposes a method to enhance the power quality of the medium voltage multilevel inverter based induction motor drive system. An 18-pulse AC-DC converter is used to feed a 27-level inverter based vector controlled induction motor drive (VCIMD). Using this configuration, the input supply current distortion decreases to meet the demand of an IEEE-519 standard. The distortion in the 27-level inverter output voltage and its switch cost are decreased impressively with an increase in the number of AC-output voltage levels. As the steps of output voltage are increased, it is switched at low switching frequency. The proposed drive system is examined in the all possible operating conditions of an induction motor. The proposed 18-pulse AC-DC converter fed 27-level inverter for VCIMD is modelled and its performance is simulated in Simulink/MATLAB environment to demonstrate its effectiveness for the medium and large rating applications.
{"title":"An18-pulse AC-DC converter-fed 27-level inverter based vector controlled induction motor drive","authors":"Piyush Kant, Bhim Singh","doi":"10.1109/POWERI.2016.8077320","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077320","url":null,"abstract":"This paper proposes a method to enhance the power quality of the medium voltage multilevel inverter based induction motor drive system. An 18-pulse AC-DC converter is used to feed a 27-level inverter based vector controlled induction motor drive (VCIMD). Using this configuration, the input supply current distortion decreases to meet the demand of an IEEE-519 standard. The distortion in the 27-level inverter output voltage and its switch cost are decreased impressively with an increase in the number of AC-output voltage levels. As the steps of output voltage are increased, it is switched at low switching frequency. The proposed drive system is examined in the all possible operating conditions of an induction motor. The proposed 18-pulse AC-DC converter fed 27-level inverter for VCIMD is modelled and its performance is simulated in Simulink/MATLAB environment to demonstrate its effectiveness for the medium and large rating applications.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"370 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":"133247761","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/POWERI.2016.8077332
S. Bhasker, M. Tripathy, Vishal Kumar
This paper describes a technique for the detection of type of internal fault in an indirect symmetrical phase shift transformer (ISPST). An application of Pattern Recognition Network (PRN) is proposed as a core classifier to identify the type of internal fault. Four type of internal faults (turn-to-turn (TT), line-to-ground (LG), two line-to-ground (LLG), and three line-to-ground (LLLG)) have been classified. Numerous test cases of internal fault in an ISPST have been using PSCAD/EMTDC software. These cases are formed on the basic variation of different parameters of ISPST like fault inception angle, fault resistance loading condition and percentage of winding. The accuracy of the proposed technique is evaluated over a large number of cases and it is observed that the technique gives the results with high accuracy even in presence of noise in the signal.
{"title":"Identification of type of internal fault in indirect symmetrical phase shift transformer based on PRN","authors":"S. Bhasker, M. Tripathy, Vishal Kumar","doi":"10.1109/POWERI.2016.8077332","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077332","url":null,"abstract":"This paper describes a technique for the detection of type of internal fault in an indirect symmetrical phase shift transformer (ISPST). An application of Pattern Recognition Network (PRN) is proposed as a core classifier to identify the type of internal fault. Four type of internal faults (turn-to-turn (TT), line-to-ground (LG), two line-to-ground (LLG), and three line-to-ground (LLLG)) have been classified. Numerous test cases of internal fault in an ISPST have been using PSCAD/EMTDC software. These cases are formed on the basic variation of different parameters of ISPST like fault inception angle, fault resistance loading condition and percentage of winding. The accuracy of the proposed technique is evaluated over a large number of cases and it is observed that the technique gives the results with high accuracy even in presence of noise in the signal.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"176 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":"133673264","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/POWERI.2016.8077355
Sushma Lohia, Om Prakash Mahela, S. Ola
The placement of shunt capacitor banks at optimal locations in the distribution network and their sizing can effectively reduce the losses in the utility network. It also helps in the maximum active power flow through the existing distribution lines which. This also increases the power transfer capacity of feeders and improves the voltage profile of the feeders which leads to reduced investment of transmission network. This paper presents a method for optimal placement and sizing of the capacitors in radial distribution feeder using Genetic algorithm (GA) with an objective of loss reduction and voltage profile improvement. The results have been validated using MATLAB programming. An IEEE 33-bus distribution test feeder is employed for testing the proposed algorithm. The optimal sizing of the capacitors has been suggested in terms of the kVAr.
{"title":"Optimal capacitor placement in distribution system using genetic algorithm","authors":"Sushma Lohia, Om Prakash Mahela, S. Ola","doi":"10.1109/POWERI.2016.8077355","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077355","url":null,"abstract":"The placement of shunt capacitor banks at optimal locations in the distribution network and their sizing can effectively reduce the losses in the utility network. It also helps in the maximum active power flow through the existing distribution lines which. This also increases the power transfer capacity of feeders and improves the voltage profile of the feeders which leads to reduced investment of transmission network. This paper presents a method for optimal placement and sizing of the capacitors in radial distribution feeder using Genetic algorithm (GA) with an objective of loss reduction and voltage profile improvement. The results have been validated using MATLAB programming. An IEEE 33-bus distribution test feeder is employed for testing the proposed algorithm. The optimal sizing of the capacitors has been suggested in terms of the kVAr.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"189 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":"122053008","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/POWERI.2016.8077338
J. S. Reddy, A. Chakraborti, B. Das
This paper mainly focuses on an automatic solar tracking system to maximize the utilization of solar energy and improves the energy conversion efficiency of the photovoltaic (PV) system. It is a closed loop sun positioning mechanism relative to the earth and makes the uniform distribution of solar radiation over an area of the PV panel. The incorporated tracking system is sufficiently devised for two degrees of freedom, being sun's Zenith or Elevation and Azimuthal angles, are covering the four principal directions. A photo sensor platform is designed and used for finding the accurate position of the sun and monitoring the weather conditions. It uses two stepper motors for driving the azimuthal and zenith positions of the sun and independently controlled each. The prototype model is designed in such way that it will provide an automatic braking against windstorm or gusts.
{"title":"Implementation and practical evaluation of an automatic solar tracking system for different weather conditions","authors":"J. S. Reddy, A. Chakraborti, B. Das","doi":"10.1109/POWERI.2016.8077338","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077338","url":null,"abstract":"This paper mainly focuses on an automatic solar tracking system to maximize the utilization of solar energy and improves the energy conversion efficiency of the photovoltaic (PV) system. It is a closed loop sun positioning mechanism relative to the earth and makes the uniform distribution of solar radiation over an area of the PV panel. The incorporated tracking system is sufficiently devised for two degrees of freedom, being sun's Zenith or Elevation and Azimuthal angles, are covering the four principal directions. A photo sensor platform is designed and used for finding the accurate position of the sun and monitoring the weather conditions. It uses two stepper motors for driving the azimuthal and zenith positions of the sun and independently controlled each. The prototype model is designed in such way that it will provide an automatic braking against windstorm or gusts.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"165 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":"115272244","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/POWERI.2016.8077353
Uma Syamkumar, B. Jayanand
In this paper, a single- stage smoothing filter algorithm is used for the speed- sensorless field-oriented control of induction motors and is verified experimentally. A fifth-order model of the induction machine (IM) is used for the estimation of rotor currents and speed. The uncertainties in measurement and model are accounted for. The experiment is carried out on a closed loop field- oriented system. An estimate of the state variables in the next instant is made, using the conventional extended Kalman filter (EKF). This estimate is used to smoothen the estimate of the previous instant. This refinement is found to improve the estimates of the previous and next instantces, since an additional data point is made use of. Using the measured stator phase voltages and currents, speed is estimated. The results are compared with those with the Extended Kalman Filter. The algorithm is found to make improvement in the transient part of response of the system. The performance of the system for different reference speeds is also analyzed. It is observed that the transient performance is improved and estimation remains good for a range of values of process and measurement error covariances.
{"title":"A single stage smoothing filter for the speed estimation of three phase induction motor","authors":"Uma Syamkumar, B. Jayanand","doi":"10.1109/POWERI.2016.8077353","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077353","url":null,"abstract":"In this paper, a single- stage smoothing filter algorithm is used for the speed- sensorless field-oriented control of induction motors and is verified experimentally. A fifth-order model of the induction machine (IM) is used for the estimation of rotor currents and speed. The uncertainties in measurement and model are accounted for. The experiment is carried out on a closed loop field- oriented system. An estimate of the state variables in the next instant is made, using the conventional extended Kalman filter (EKF). This estimate is used to smoothen the estimate of the previous instant. This refinement is found to improve the estimates of the previous and next instantces, since an additional data point is made use of. Using the measured stator phase voltages and currents, speed is estimated. The results are compared with those with the Extended Kalman Filter. The algorithm is found to make improvement in the transient part of response of the system. The performance of the system for different reference speeds is also analyzed. It is observed that the transient performance is improved and estimation remains good for a range of values of process and measurement error covariances.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"5 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":"114696929","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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