Pub Date : 2016-10-01DOI: 10.1109/APPEEC.2016.7779668
Xueping Li, Liangxing Fang
Granular computing, as a new and rapidly growing paradigm of information processing, has attracted many researchers and practitioners. The large power grid could be decomposed into particles with different granularity according to granular computing method. Based on this, a hierarchical quotient space model could be built, so it would be convenient to choose the proper granule in the quotient space rapidly to find the optimal power flow under different circumstances. Thereby reducing the complexity of problem solving processes. The network topology is taken into consideration during the process of granulation, so the equivalent simplification of the network topology can accelerate the calculation speed.
{"title":"Research on economic dispatch of large power grid based on granular computing","authors":"Xueping Li, Liangxing Fang","doi":"10.1109/APPEEC.2016.7779668","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779668","url":null,"abstract":"Granular computing, as a new and rapidly growing paradigm of information processing, has attracted many researchers and practitioners. The large power grid could be decomposed into particles with different granularity according to granular computing method. Based on this, a hierarchical quotient space model could be built, so it would be convenient to choose the proper granule in the quotient space rapidly to find the optimal power flow under different circumstances. Thereby reducing the complexity of problem solving processes. The network topology is taken into consideration during the process of granulation, so the equivalent simplification of the network topology can accelerate the calculation speed.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126784770","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}
A hybrid energy storage system (HESS) is integrated with a wind farm to smooth out its fluctuations in order to reduce the impact on the grids. This paper presents a cutoff frequency method for optimizing the HESS for smoothing fluctuations of wind energy. The main goal of the proposed method is to find the rated power and capacity of HESS. Based on spectrum analysis results and power ramp rate, the best cutoff frequency, expected power and the minimum absorb power are determined. According to the characteristics of HESS and the safety specifications, the minimum sizing of the battery and the super capacitor were selected. The proposed method was verified based on historical wind power data and Chinese Standard of grid-connected.
{"title":"A method for optimal sizing hybrid energy storage system for smoothing Fluctuations of Wind Power","authors":"Mingyu Pang, Yikai Shi, Wendong Wang, Xiaoqing Yuan","doi":"10.1109/APPEEC.2016.7779913","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779913","url":null,"abstract":"A hybrid energy storage system (HESS) is integrated with a wind farm to smooth out its fluctuations in order to reduce the impact on the grids. This paper presents a cutoff frequency method for optimizing the HESS for smoothing fluctuations of wind energy. The main goal of the proposed method is to find the rated power and capacity of HESS. Based on spectrum analysis results and power ramp rate, the best cutoff frequency, expected power and the minimum absorb power are determined. According to the characteristics of HESS and the safety specifications, the minimum sizing of the battery and the super capacitor were selected. The proposed method was verified based on historical wind power data and Chinese Standard of grid-connected.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"83 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115085392","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779531
Dan Liu
Consistency of batteries determines life and discharge period of battery Pack and many factors. As to difference in performance of batteries which have been used for a period of time, a balancing method based on SOC and voltage detection is proposed in this paper. On the aspect of balancing strategy, difference between instant voltage and SOC needs to be evaluated by referring a weight table to choose appropriate charging or discharging strategy in different situation. As for detection and control of hardware, a two-way DC-DC balancing circuit is established to balance power between packed batteries. Finally, a platform composed by 12 cell lithium-ion batteries is established to perform a charging and discharging experiment with 0.3 time of rated power. The effectiveness of balancing strategy is examined by comparing SOC results at end of the entire experiment in both situation with and without balancing strategy.
{"title":"Research on portable balance devices and balancing strategy for batteries","authors":"Dan Liu","doi":"10.1109/APPEEC.2016.7779531","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779531","url":null,"abstract":"Consistency of batteries determines life and discharge period of battery Pack and many factors. As to difference in performance of batteries which have been used for a period of time, a balancing method based on SOC and voltage detection is proposed in this paper. On the aspect of balancing strategy, difference between instant voltage and SOC needs to be evaluated by referring a weight table to choose appropriate charging or discharging strategy in different situation. As for detection and control of hardware, a two-way DC-DC balancing circuit is established to balance power between packed batteries. Finally, a platform composed by 12 cell lithium-ion batteries is established to perform a charging and discharging experiment with 0.3 time of rated power. The effectiveness of balancing strategy is examined by comparing SOC results at end of the entire experiment in both situation with and without balancing strategy.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116083742","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779558
S. Prakash, S. Mishra, N. Padhy
This paper presents a coordinated control of a grid connected DC micro-grid between the energy storage system (ESS) DC-DC converter and the VSC. The three different mode of operation is presented i.e (a) Autonomous mode when the DC micro-grid is not connected to grid (b) Current control mode, i.e when either of the ESS or VSC are in current control mode and (C) Dual mode, when both ESS and VSC are in DC link voltage control mode. A MATLAB Simulink model results is given to validate the results in each mode of operation.
{"title":"Coordinated control of a grid connected DC micro-grid with multiple renewable sources","authors":"S. Prakash, S. Mishra, N. Padhy","doi":"10.1109/APPEEC.2016.7779558","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779558","url":null,"abstract":"This paper presents a coordinated control of a grid connected DC micro-grid between the energy storage system (ESS) DC-DC converter and the VSC. The three different mode of operation is presented i.e (a) Autonomous mode when the DC micro-grid is not connected to grid (b) Current control mode, i.e when either of the ESS or VSC are in current control mode and (C) Dual mode, when both ESS and VSC are in DC link voltage control mode. A MATLAB Simulink model results is given to validate the results in each mode of operation.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116226794","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779483
S. Dawoud, Xiangning Lin, Firas M. F. Flaih, Merfat I. Okba
Renewable distributed generation (RDG) has an overall positive impact on a microgrid. These RDGs are usually located near to the load centers which lead to some benefits such as; system power loss; voltage profile and stability improvement; environmental friendliness, rescheduling system upgrading, and reliability enhancement. In this paper, the particle swarm optimization (PSO) has been proposed to find the optimal location of solar photovoltaic (SPV) based in a microgrid. PSO has been applied to improve the power losses of radial networks considering different constraints related to the distribution network. A novel average overall voltage stability index has been proposed, in this paper which can quantify voltage stability levels of buses in a microgrid. Beta probability distribution function has been used to calculate the solar radiation. The proposed technique has been tested on 33-bus and 69-bus microgrid system. The improvements in voltage profile and average overall voltage stability index of the RDGs have been observed. To confirm the suggested PSO technique the results have been compared with the other popular algorithms.
{"title":"PSO algorithm for optimal placement of multiple SPV based distributed generators in Microgrids","authors":"S. Dawoud, Xiangning Lin, Firas M. F. Flaih, Merfat I. Okba","doi":"10.1109/APPEEC.2016.7779483","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779483","url":null,"abstract":"Renewable distributed generation (RDG) has an overall positive impact on a microgrid. These RDGs are usually located near to the load centers which lead to some benefits such as; system power loss; voltage profile and stability improvement; environmental friendliness, rescheduling system upgrading, and reliability enhancement. In this paper, the particle swarm optimization (PSO) has been proposed to find the optimal location of solar photovoltaic (SPV) based in a microgrid. PSO has been applied to improve the power losses of radial networks considering different constraints related to the distribution network. A novel average overall voltage stability index has been proposed, in this paper which can quantify voltage stability levels of buses in a microgrid. Beta probability distribution function has been used to calculate the solar radiation. The proposed technique has been tested on 33-bus and 69-bus microgrid system. The improvements in voltage profile and average overall voltage stability index of the RDGs have been observed. To confirm the suggested PSO technique the results have been compared with the other popular algorithms.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116531997","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779848
Lin Zhu, D. Shi
The distance backup relays configured with fixed settings may lose their pre-determined coordination, and even form a significant threat to system security due to the variety of system operation condition. There are many special temporary operation conditions in the developing power grids of China, which may be not anticipated in the offline relay coordination. Therefore, periodical online verification of relay coordination is highly desirable to detect improper or incorrect settings under the current system state. However, the verification method is also required to perform verification correctly and efficiently in large-scale power grids, whose importance is similar to that of equal-area criterion for transient stability analysis, and eigenvalue methodology for low frequency oscillation analysis. A new verification method using setting comparison is presented, which performs verification more conveniently and efficiently than conventional method using reach point comparison. The application in large-scale power grids demonstrates the availability of the proposed method.
{"title":"A method for online relay coordination verification using setting comparison","authors":"Lin Zhu, D. Shi","doi":"10.1109/APPEEC.2016.7779848","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779848","url":null,"abstract":"The distance backup relays configured with fixed settings may lose their pre-determined coordination, and even form a significant threat to system security due to the variety of system operation condition. There are many special temporary operation conditions in the developing power grids of China, which may be not anticipated in the offline relay coordination. Therefore, periodical online verification of relay coordination is highly desirable to detect improper or incorrect settings under the current system state. However, the verification method is also required to perform verification correctly and efficiently in large-scale power grids, whose importance is similar to that of equal-area criterion for transient stability analysis, and eigenvalue methodology for low frequency oscillation analysis. A new verification method using setting comparison is presented, which performs verification more conveniently and efficiently than conventional method using reach point comparison. The application in large-scale power grids demonstrates the availability of the proposed method.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122327410","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779857
Chenchen Chen, Chunlin Guo, Z. Man, X. Tong
In recent years, the integration of renewable energy has caused problems of grid frequency quality. However, Electric vehicles (EVs) which can be a mobile energy storage and controllable load provide a new way to solve the problems. This article addressed a fuzzy self-adaptive PID power response strategy and established a model considering EV frequency regulation with the software MATLAB. With the model, several different scenarios were studied to find out how frequency deviation is reduced with EV participating in frequency regulation. It turned out that the frequency deviation and recovery time were reduced when EVs offered primary and secondary frequency regulation. And the fuzzy self-adaptive PID power response strategy had better performance in reducing frequency deviation and recovery time. Therefore, the power system could be more stable and economic based on the strategy.
{"title":"Control strategy research on frequency regulation of power system considering Electric vehicles","authors":"Chenchen Chen, Chunlin Guo, Z. Man, X. Tong","doi":"10.1109/APPEEC.2016.7779857","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779857","url":null,"abstract":"In recent years, the integration of renewable energy has caused problems of grid frequency quality. However, Electric vehicles (EVs) which can be a mobile energy storage and controllable load provide a new way to solve the problems. This article addressed a fuzzy self-adaptive PID power response strategy and established a model considering EV frequency regulation with the software MATLAB. With the model, several different scenarios were studied to find out how frequency deviation is reduced with EV participating in frequency regulation. It turned out that the frequency deviation and recovery time were reduced when EVs offered primary and secondary frequency regulation. And the fuzzy self-adaptive PID power response strategy had better performance in reducing frequency deviation and recovery time. Therefore, the power system could be more stable and economic based on the strategy.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"52 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114039091","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779888
Liuwang Wang, Yongli Zhu, Y. Jia
The rapid development of smart grid needs a lot of investment in smart substation. Data collected in monitoring of transformation equipments growing remarkably fast, big data becomes increasingly evident. Though existing platforms or frameworks were designed for processing big data in power equipments monitoring, they were all based on Hadoop which is only suitable for offline data analysis. In order to meet diversified real-time demand of big data analysis in transformation equipment monitoring, a novel hybrid cloud platform based on mainstream open source technologies is designed in this paper. According to characteristics of monitoring data and real-time demand level of consumer, data can be processed by suitable computing framework within appropriate resource limits. In order to provide more insights into the effectiveness of the hybrid platform, case studies in different scenarios are conducted on a preliminary one.
{"title":"A hybrid cloud platform for diversified real-time demand in transformation equipment monitoring","authors":"Liuwang Wang, Yongli Zhu, Y. Jia","doi":"10.1109/APPEEC.2016.7779888","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779888","url":null,"abstract":"The rapid development of smart grid needs a lot of investment in smart substation. Data collected in monitoring of transformation equipments growing remarkably fast, big data becomes increasingly evident. Though existing platforms or frameworks were designed for processing big data in power equipments monitoring, they were all based on Hadoop which is only suitable for offline data analysis. In order to meet diversified real-time demand of big data analysis in transformation equipment monitoring, a novel hybrid cloud platform based on mainstream open source technologies is designed in this paper. According to characteristics of monitoring data and real-time demand level of consumer, data can be processed by suitable computing framework within appropriate resource limits. In order to provide more insights into the effectiveness of the hybrid platform, case studies in different scenarios are conducted on a preliminary one.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"79 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121915263","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779521
Pan Zhang, Yanxia Zhang, Gaopeng Meng
Considering the situations that the fault information in the distribution networks may be omitted and misinformed, their influence on the fault locating results are discussed in this paper, and a fault-tolerant fault location method is proposed based on the wrong-logic region detection. Firstly, the definition of wrong-logic area is given according to the minimum power distribution area. Then, from the following three aspects of whether to locate the correct fault area, whether to locate the false fault area and whether to find the wrong-logic region, the fault locating results are classified into three situations. Considering these three situations, a fault-tolerant fault location method is put forward in this paper. The simulation result shows and verifies the correctness and the good fault tolerance ability of this method. Its processing procedure is simple and it has high practical value.
{"title":"A fault location method in distribution networks with fault-tolerant ability based on the wrong-logic region detection","authors":"Pan Zhang, Yanxia Zhang, Gaopeng Meng","doi":"10.1109/APPEEC.2016.7779521","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779521","url":null,"abstract":"Considering the situations that the fault information in the distribution networks may be omitted and misinformed, their influence on the fault locating results are discussed in this paper, and a fault-tolerant fault location method is proposed based on the wrong-logic region detection. Firstly, the definition of wrong-logic area is given according to the minimum power distribution area. Then, from the following three aspects of whether to locate the correct fault area, whether to locate the false fault area and whether to find the wrong-logic region, the fault locating results are classified into three situations. Considering these three situations, a fault-tolerant fault location method is put forward in this paper. The simulation result shows and verifies the correctness and the good fault tolerance ability of this method. Its processing procedure is simple and it has high practical value.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122166603","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 : 2016-10-01DOI: 10.1109/APPEEC.2016.7779852
Hao Gong, Hongtao Wang
The presence of higher penetration of renewable energy generation (RES) requires more flexible scheduling resources to maintain the balance between demand side and generation side. In addition to traditional reserve resources, demand response (DR) programs have gained much attention recently to mitigate wind power's volatility and uncertainty. To better accommodate wind power, this paper proposes a chance-constrained day-ahead generation scheduling model for variable energy resources considering DR. The model considers hourly forecast errors of wind power output and DR. A chance-constrained stochastic programming formulation is presented for the day-ahead scheduling model. Operation risk chance constraints for load shedding and wind curtailment are formulated. Reserve requirements are formulated as chance constraints in which power system reliability requirements are to be satisfied with a presumed level of high probability. The loss of load probability and the probability of wind power curtailment is less than certain level. The formulation captures both wind power output and DR uncertainties. The chance-constrained stochastic programming formulation is converted into an equivalent linear deterministic problem. The proposed model is tested in PJM 5-bus system.
{"title":"Day-ahead generation scheduling for variable energy resources considering demand response","authors":"Hao Gong, Hongtao Wang","doi":"10.1109/APPEEC.2016.7779852","DOIUrl":"https://doi.org/10.1109/APPEEC.2016.7779852","url":null,"abstract":"The presence of higher penetration of renewable energy generation (RES) requires more flexible scheduling resources to maintain the balance between demand side and generation side. In addition to traditional reserve resources, demand response (DR) programs have gained much attention recently to mitigate wind power's volatility and uncertainty. To better accommodate wind power, this paper proposes a chance-constrained day-ahead generation scheduling model for variable energy resources considering DR. The model considers hourly forecast errors of wind power output and DR. A chance-constrained stochastic programming formulation is presented for the day-ahead scheduling model. Operation risk chance constraints for load shedding and wind curtailment are formulated. Reserve requirements are formulated as chance constraints in which power system reliability requirements are to be satisfied with a presumed level of high probability. The loss of load probability and the probability of wind power curtailment is less than certain level. The formulation captures both wind power output and DR uncertainties. The chance-constrained stochastic programming formulation is converted into an equivalent linear deterministic problem. The proposed model is tested in PJM 5-bus system.","PeriodicalId":117485,"journal":{"name":"2016 IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122233223","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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