Pub Date : 2015-07-26DOI: 10.1109/PESGM.2015.7285738
Hang Thu Le
Lab training is considered a key for producing skilled workforce required by all engineering sectors. Apart from conceptual understanding, good lab training should provide students with important skills such as design, professional, analytical, and social skills. This paper presents a new lab teaching method which combines “hands-on” and “simulated” labs, along with strong guidance from the instructor. The method is used to teach three core labs at Cal Poly Pomona ECE department for one academic year. The obtained results show that the method augments the student lab score by up to 7 points. The student satisfaction is consistently higher. Between 82.8% and 86% of students are happy with the instructor teaching effectiveness. Lab teaching and management are more effective using tools such as Sign-in and Sign-out sheet, set of benchmarks, and guide for reporting. Overall, the student core skills, namely, design, professional, social, analytical, and report-writing skills are significantly improved.
{"title":"Guidance-based hybrid lab training method for enhancing core skills of EE students","authors":"Hang Thu Le","doi":"10.1109/PESGM.2015.7285738","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285738","url":null,"abstract":"Lab training is considered a key for producing skilled workforce required by all engineering sectors. Apart from conceptual understanding, good lab training should provide students with important skills such as design, professional, analytical, and social skills. This paper presents a new lab teaching method which combines “hands-on” and “simulated” labs, along with strong guidance from the instructor. The method is used to teach three core labs at Cal Poly Pomona ECE department for one academic year. The obtained results show that the method augments the student lab score by up to 7 points. The student satisfaction is consistently higher. Between 82.8% and 86% of students are happy with the instructor teaching effectiveness. Lab teaching and management are more effective using tools such as Sign-in and Sign-out sheet, set of benchmarks, and guide for reporting. Overall, the student core skills, namely, design, professional, social, analytical, and report-writing skills are significantly improved.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116115363","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286307
Roy Boyer
A collection of slides from the author's conference presentation was given. Additional ways to value transmission expansion were presented.
本文提供了作者在会议上演讲的幻灯片选集。提出了价值传递扩展的其他途径。
{"title":"Some ways to value transmission expansion","authors":"Roy Boyer","doi":"10.1109/PESGM.2015.7286307","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286307","url":null,"abstract":"A collection of slides from the author's conference presentation was given. Additional ways to value transmission expansion were presented.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"403 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116131780","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286004
Md. Ashfanoor Kabir, I. Husain
New winding configurations for mutually coupled salient pole switched reluctance machines (MCSRMs) have been proposed that enables the application of three-phase standard inverters for variable speed drives. The proposed topologies comprise phase windings carrying balanced three phase currents from standard inverters along with DC excitation coils in the stator slots. Both concentrated and distributed hybrid winding configurations are proposed and performances of these MCSRMs are compared with that of the conventional SRM under the same machine geometry and phase excitation levels. The analysis and results show that the proposed machine configurations with standard inverters are more suitable for low cost, variable speed drives with higher power densities and lower torque ripples compared to conventional SRM drives.
{"title":"Hybrid excitation topologies for three-phase mutually coupled reluctance machine with standard inverters","authors":"Md. Ashfanoor Kabir, I. Husain","doi":"10.1109/PESGM.2015.7286004","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286004","url":null,"abstract":"New winding configurations for mutually coupled salient pole switched reluctance machines (MCSRMs) have been proposed that enables the application of three-phase standard inverters for variable speed drives. The proposed topologies comprise phase windings carrying balanced three phase currents from standard inverters along with DC excitation coils in the stator slots. Both concentrated and distributed hybrid winding configurations are proposed and performances of these MCSRMs are compared with that of the conventional SRM under the same machine geometry and phase excitation levels. The analysis and results show that the proposed machine configurations with standard inverters are more suitable for low cost, variable speed drives with higher power densities and lower torque ripples compared to conventional SRM drives.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116378715","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286068
M. Haghifam, M. Esmaeeli, A. Kazemi, H. Shayanfar
In this paper, an approach is proposed for planning distribution networks in which the placement of distribution transformer is optimally planned. The size, number, and placement of distribution transformers are optimally determined in order to improve system reliability and to minimize the losses under load growth. An objective function is constituted, composed of the investment cost, maintenance cost, loss cost, and reliability cost. The reliability worth is not usually considered in the optimization of the distribution substation placement. However, it may be effective on the planning problem. The proposed approach is applied to a test system consisting of 42 electric load points. It is observed that the considering reliability in the planning approach reduces the total cost of the distribution transformer placement. However, the associated investment cost is increased but the reliability cost is more decreased.
{"title":"Optimal placement of the distribution substations to improve reliability under load growth","authors":"M. Haghifam, M. Esmaeeli, A. Kazemi, H. Shayanfar","doi":"10.1109/PESGM.2015.7286068","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286068","url":null,"abstract":"In this paper, an approach is proposed for planning distribution networks in which the placement of distribution transformer is optimally planned. The size, number, and placement of distribution transformers are optimally determined in order to improve system reliability and to minimize the losses under load growth. An objective function is constituted, composed of the investment cost, maintenance cost, loss cost, and reliability cost. The reliability worth is not usually considered in the optimization of the distribution substation placement. However, it may be effective on the planning problem. The proposed approach is applied to a test system consisting of 42 electric load points. It is observed that the considering reliability in the planning approach reduces the total cost of the distribution transformer placement. However, the associated investment cost is increased but the reliability cost is more decreased.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116441331","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7285854
S. Mohanty, N. Kishor, P. Ray, J. Catalão
In this paper, islanding detection in a hybrid distributed generation (DG) system is analyzed by the use of hyperbolic S-transform, time-time transform and mathematical morphology methods. The merits of these methods are thoroughly compared against commonly adopted wavelet transform and S-transform techniques, as a new contribution to earlier studies. The hybrid DG system consists of photovoltaic and wind energy systems connected to the grid within the IEEE 30-bus system. Negative sequence component of the voltage signal is extracted at the point of common coupling and passed through the above mentioned techniques. The efficacy of the proposed methods is also compared by energy based technique with proper threshold selection to accurately detect the islanding phenomena. Further, to augment the accuracy of the result, the classification is done using support vector machine to distinguish islanding from other power quality disturbances. The results demonstrate effective performance and feasibility of the proposed techniques for islanding detection under both noise-free and noisy environments, and also in the presence of harmonics.
{"title":"Comparative study of advanced signal processing techniques for islanding detection in a hybrid distributed generation system","authors":"S. Mohanty, N. Kishor, P. Ray, J. Catalão","doi":"10.1109/PESGM.2015.7285854","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285854","url":null,"abstract":"In this paper, islanding detection in a hybrid distributed generation (DG) system is analyzed by the use of hyperbolic S-transform, time-time transform and mathematical morphology methods. The merits of these methods are thoroughly compared against commonly adopted wavelet transform and S-transform techniques, as a new contribution to earlier studies. The hybrid DG system consists of photovoltaic and wind energy systems connected to the grid within the IEEE 30-bus system. Negative sequence component of the voltage signal is extracted at the point of common coupling and passed through the above mentioned techniques. The efficacy of the proposed methods is also compared by energy based technique with proper threshold selection to accurately detect the islanding phenomena. Further, to augment the accuracy of the result, the classification is done using support vector machine to distinguish islanding from other power quality disturbances. The results demonstrate effective performance and feasibility of the proposed techniques for islanding detection under both noise-free and noisy environments, and also in the presence of harmonics.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122815444","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286554
Jizhong Zhu, N. Zhou
This paper analyzes the characteristic of the recovery voltage when single phase earth fault occurs in EHV/UHV transmission line with shunt reactor. According to the different frequency characteristics of the recovery voltage, a new method based on power spectrum to distinguish the temporary faults from the permanent faults in EHV/UHV transmission lines is proposed. Through using the distribution of spectral line nearby the power frequency in power spectrum, this method can identify the type of a fault. The criterion that doesn't need high frequency contents is easy to set and implement. Power spectrums are calculated and analyzed by use of MATLAB/ SIMULINK. The results show that the proposed method is accurate and feasible.
{"title":"Analysis of the fault type for adaptive single-phase autoreclosure","authors":"Jizhong Zhu, N. Zhou","doi":"10.1109/PESGM.2015.7286554","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286554","url":null,"abstract":"This paper analyzes the characteristic of the recovery voltage when single phase earth fault occurs in EHV/UHV transmission line with shunt reactor. According to the different frequency characteristics of the recovery voltage, a new method based on power spectrum to distinguish the temporary faults from the permanent faults in EHV/UHV transmission lines is proposed. Through using the distribution of spectral line nearby the power frequency in power spectrum, this method can identify the type of a fault. The criterion that doesn't need high frequency contents is easy to set and implement. Power spectrums are calculated and analyzed by use of MATLAB/ SIMULINK. The results show that the proposed method is accurate and feasible.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114165334","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7285701
H. Pendse, G. Karady
Gas Insulated Transmission Lines (GIL) is a high power transmission technology developed for the energy transfer from remote locations to the load centers. It uses SF6 or a mixture of SF6 and N2 as an insulator. Because of the high global warming potential of SF6 and unavoidable gas leakages throughout the length of the line, there is a need to find substitute for SF6. Considering the excellent high voltage insulating properties and lightweight structure, the foam insulating material can be a possible solution for the above mentioned problem. The following paper describes the steps involved in the development of the simulation model for the insulating foam for the application in GIL in order to analyze electric field distribution. This is demonstrated by modeling a small section of syntactic foam in COMSOL Multiphysics software along with AutoCAD and Microsoft Excel. The base electric field for the simulations is maintained at 4.39 kV/mm which is the maximum field in 400 kV GIL. The deviation of the electric field distribution from the base electric field is determined for a cubical model with side 1 mm. The effect of metal particles on electric field distribution is also observed as a part of study.
{"title":"Development of the insulating foam model for the study of electric field distribution for the application of Gas Insulated Transmission Line","authors":"H. Pendse, G. Karady","doi":"10.1109/PESGM.2015.7285701","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285701","url":null,"abstract":"Gas Insulated Transmission Lines (GIL) is a high power transmission technology developed for the energy transfer from remote locations to the load centers. It uses SF6 or a mixture of SF6 and N2 as an insulator. Because of the high global warming potential of SF6 and unavoidable gas leakages throughout the length of the line, there is a need to find substitute for SF6. Considering the excellent high voltage insulating properties and lightweight structure, the foam insulating material can be a possible solution for the above mentioned problem. The following paper describes the steps involved in the development of the simulation model for the insulating foam for the application in GIL in order to analyze electric field distribution. This is demonstrated by modeling a small section of syntactic foam in COMSOL Multiphysics software along with AutoCAD and Microsoft Excel. The base electric field for the simulations is maintained at 4.39 kV/mm which is the maximum field in 400 kV GIL. The deviation of the electric field distribution from the base electric field is determined for a cubical model with side 1 mm. The effect of metal particles on electric field distribution is also observed as a part of study.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114458145","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7285858
A. A. Alabduljabbar, M. Smiai
Low power factors are considered one of the pressing issues in the distribution system planning and operation particularly at countries where a monetary cost's scheme of the reactive power usage is not applied. Regulations, financial penalties and incentives, and technical solutions have all been used to improve low power factor levels. In this paper, a study and comparisons between several low power factor penalty schemes are considered leading to the most optimum method to be applied in practice. The study helps with highlighting the factors that have to be considered when designing such penalties in order to eliminate the wide difference in the adopted power factor regulations around the world. The use of the excessive reactive power/energy tariff to be the penalty for the low power factor customers seems to be the favorable choice for utilities due to its consistency and reliability. Although the case in the Kingdom of Saudi Arabia is highlighted here, the methodology is valid for other markets.
{"title":"A methodology for designing low power factor penalties in distribution networks","authors":"A. A. Alabduljabbar, M. Smiai","doi":"10.1109/PESGM.2015.7285858","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285858","url":null,"abstract":"Low power factors are considered one of the pressing issues in the distribution system planning and operation particularly at countries where a monetary cost's scheme of the reactive power usage is not applied. Regulations, financial penalties and incentives, and technical solutions have all been used to improve low power factor levels. In this paper, a study and comparisons between several low power factor penalty schemes are considered leading to the most optimum method to be applied in practice. The study helps with highlighting the factors that have to be considered when designing such penalties in order to eliminate the wide difference in the adopted power factor regulations around the world. The use of the excessive reactive power/energy tariff to be the penalty for the low power factor customers seems to be the favorable choice for utilities due to its consistency and reliability. Although the case in the Kingdom of Saudi Arabia is highlighted here, the methodology is valid for other markets.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114500622","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7285852
Tik Son Wong, J. Lopez-Roldan, T. Saha
Gas-insulated switchgears (GIS) are emerging as more capable power system assets than conventional air-insulated switchgears (AIS), especially in terms of operational reliability and maintenance requirements. However, insufficient consideration is often given to comparing GIS and AIS substation project options. Therefore, a more effective approach is needed to better inform project investment decisions. This paper outlines the development of a project life-cycle cost-estimating software tool for GIS and equivalent AIS substation projects, and formulation of the underpinning economic models. The cost-estimating tool provides practical and objective comparisons between considered GIS and AIS substation projects, and opportunities to investigate major cost contributing factors in substation project cost estimates.
{"title":"Development of a life cycle cost estimating tool to compare GIS and AIS substation projects","authors":"Tik Son Wong, J. Lopez-Roldan, T. Saha","doi":"10.1109/PESGM.2015.7285852","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7285852","url":null,"abstract":"Gas-insulated switchgears (GIS) are emerging as more capable power system assets than conventional air-insulated switchgears (AIS), especially in terms of operational reliability and maintenance requirements. However, insufficient consideration is often given to comparing GIS and AIS substation project options. Therefore, a more effective approach is needed to better inform project investment decisions. This paper outlines the development of a project life-cycle cost-estimating software tool for GIS and equivalent AIS substation projects, and formulation of the underpinning economic models. The cost-estimating tool provides practical and objective comparisons between considered GIS and AIS substation projects, and opportunities to investigate major cost contributing factors in substation project cost estimates.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"231 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114597794","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 : 2015-07-26DOI: 10.1109/PESGM.2015.7286558
S. Liao, Jian Xu, Yuanzhan Sun, Wenzhong Gao, Liang Xu, Lei Huang, Xiaoming Li, Junhe Gu, Jianxun Dong
Maintaining frequency stability is a necessity for an isolated power system. The frequency regulation participation of photovoltaic generation system (PVs) is vital for an isolated power system with large scale PVs penetration, especially when the frequency regulation capacity of the isolated power system is limited. The deloaded operation for PVs can provide supplemental primary frequency regulation capacity. With a high value of deload margin, PVs have a higher capacity for frequency regulation, but this may result in economic loss. Hence, there should be a tradeoff between the economic effect and the capability for frequency support. Taking into account of the frequency regulation capacity demand for PVs and the operation benefits of PVs, a WAMS-based method to calculate the deload margin for PVs is proposed in this paper. In addition, the corresponding droop control strategy is designed to make full use of PVs' reserve capacity. An isolated industrial system for aluminum production driven by coal-fired power and large scale PVs is studied as an example case. Simulation is done with real-time digital simulator (RTDS) platform and results verify the effectiveness of the proposed frequency regulation strategy.
{"title":"WAMS-based frequency regulation strategy for photovoltaic system in isolated power systems","authors":"S. Liao, Jian Xu, Yuanzhan Sun, Wenzhong Gao, Liang Xu, Lei Huang, Xiaoming Li, Junhe Gu, Jianxun Dong","doi":"10.1109/PESGM.2015.7286558","DOIUrl":"https://doi.org/10.1109/PESGM.2015.7286558","url":null,"abstract":"Maintaining frequency stability is a necessity for an isolated power system. The frequency regulation participation of photovoltaic generation system (PVs) is vital for an isolated power system with large scale PVs penetration, especially when the frequency regulation capacity of the isolated power system is limited. The deloaded operation for PVs can provide supplemental primary frequency regulation capacity. With a high value of deload margin, PVs have a higher capacity for frequency regulation, but this may result in economic loss. Hence, there should be a tradeoff between the economic effect and the capability for frequency support. Taking into account of the frequency regulation capacity demand for PVs and the operation benefits of PVs, a WAMS-based method to calculate the deload margin for PVs is proposed in this paper. In addition, the corresponding droop control strategy is designed to make full use of PVs' reserve capacity. An isolated industrial system for aluminum production driven by coal-fired power and large scale PVs is studied as an example case. Simulation is done with real-time digital simulator (RTDS) platform and results verify the effectiveness of the proposed frequency regulation strategy.","PeriodicalId":423639,"journal":{"name":"2015 IEEE Power & Energy Society General Meeting","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122068024","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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