Pub Date : 2017-07-01DOI: 10.1109/EUROCON.2017.8011243
Andrijana Kuhar, L. Grcev, B. Markovski
Electromagnetic Models (EM) for analysis of grounding systems are based on least possible approximations in the solution of Maxwell's equations. The complexity of the EM calculations motivated the creation of more engineer-oriented and less time consuming methods for analysis of grounding systems. One of the most commonly used methods is the transmission line (TL) model. In this paper a new, improved formula for the inductivity parameter of the TL model is proposed. The new formula is implemented to calculate the grounding impedance of vertical and horizontal grounding conductors, as well as the transient potential at feed point when a subsequent lightning stroke is injected. Comparison of the obtained results to the classical TL model shows a significant improvement in precision with reference to rigorous EM calculations.
{"title":"Improved TL inductivity formula for analysis of grounding conductors","authors":"Andrijana Kuhar, L. Grcev, B. Markovski","doi":"10.1109/EUROCON.2017.8011243","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011243","url":null,"abstract":"Electromagnetic Models (EM) for analysis of grounding systems are based on least possible approximations in the solution of Maxwell's equations. The complexity of the EM calculations motivated the creation of more engineer-oriented and less time consuming methods for analysis of grounding systems. One of the most commonly used methods is the transmission line (TL) model. In this paper a new, improved formula for the inductivity parameter of the TL model is proposed. The new formula is implemented to calculate the grounding impedance of vertical and horizontal grounding conductors, as well as the transient potential at feed point when a subsequent lightning stroke is injected. Comparison of the obtained results to the classical TL model shows a significant improvement in precision with reference to rigorous EM calculations.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128164353","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011164
Azra Xheladini, Sertan Deniz Saygili, F. Dikbiyik
The exam statistics are crucial for instructors to better assess the exam metrics, e.g., exam duration. However, one statistic, time spent on each question by each student, is not available or difficult to obtain by human observation. In this work, we propose a smart exam system that obtains such statistics and sends data to a web application for further processing by using an internet-of-things based technology. The information obtained by the proposed system can even be used to diagnose students with learning difficulties or disabilities, e.g., dyslexia. We provided an experimental setup and conducted experiments with volunteers. The experiments conducted during the study show that the proposed system effectively collect information and process data for the use of instructor.
{"title":"An IoT-based smart exam application","authors":"Azra Xheladini, Sertan Deniz Saygili, F. Dikbiyik","doi":"10.1109/EUROCON.2017.8011164","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011164","url":null,"abstract":"The exam statistics are crucial for instructors to better assess the exam metrics, e.g., exam duration. However, one statistic, time spent on each question by each student, is not available or difficult to obtain by human observation. In this work, we propose a smart exam system that obtains such statistics and sends data to a web application for further processing by using an internet-of-things based technology. The information obtained by the proposed system can even be used to diagnose students with learning difficulties or disabilities, e.g., dyslexia. We provided an experimental setup and conducted experiments with volunteers. The experiments conducted during the study show that the proposed system effectively collect information and process data for the use of instructor.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132555624","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011220
U. Kerin, R. Krebs
In the last ten years PMUs (Phasor Measurement Units) play a more and more important role for the on-line monitoring and analysis of the state of the electrical systems. The reasons for this development are dynamic loading of transmission systems, demand on flexibility of generation, high penetration of renewable generation and decentralized load and generation centers. PMUs today allow measuring current and voltage phasors and execute functions such as power swing recognition and island detection. Indices can be created on basis of measurements, which can be used for alarming, protection and control. A combination of measurements and indices allow for creating an overall PMU index which describes the online state of the system and consequently the change of state (tendency) of the system. The information is created in the phasor data processor (PDP) which can exchange data with a dynamic security assessment (DSA) system or/and SCADA system in order to monitor local and global system states for stability, continuous steady state analysis, short term / forecast stability analysis and remedial actions. Finally, combining PDP, DSA and SCADA enables to enact a wide area protection and control arming and disarming pre-calculated system integrity schemes.
{"title":"PMU and DSA based wide area control system: Concept and application in large longitudinal system","authors":"U. Kerin, R. Krebs","doi":"10.1109/EUROCON.2017.8011220","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011220","url":null,"abstract":"In the last ten years PMUs (Phasor Measurement Units) play a more and more important role for the on-line monitoring and analysis of the state of the electrical systems. The reasons for this development are dynamic loading of transmission systems, demand on flexibility of generation, high penetration of renewable generation and decentralized load and generation centers. PMUs today allow measuring current and voltage phasors and execute functions such as power swing recognition and island detection. Indices can be created on basis of measurements, which can be used for alarming, protection and control. A combination of measurements and indices allow for creating an overall PMU index which describes the online state of the system and consequently the change of state (tendency) of the system. The information is created in the phasor data processor (PDP) which can exchange data with a dynamic security assessment (DSA) system or/and SCADA system in order to monitor local and global system states for stability, continuous steady state analysis, short term / forecast stability analysis and remedial actions. Finally, combining PDP, DSA and SCADA enables to enact a wide area protection and control arming and disarming pre-calculated system integrity schemes.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130704768","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011230
Z. Kokolanski, V. Dimcev, D. Taskovski, M. Simić, D. Denic, Jelena Eordevic-Kozarov
Metrological evaluation of electrical power quality signal generator, designed for reproducing the standard power quality disturbances, is presented in this paper. This generator is functionally based on the virtual instrumentation software, data acquisition card and power amplifier for scaling the output voltage to the nominal power line voltage level (230 V). The realized computer-based signal generator can be used as suitable and cost effective alternative to the various instruments for testing the power quality meters and analyzers. Metrological assessment of signal generator includes calculation of measurement uncertainty components and final presentation of measurement uncertainty budget. Procedure for calculation of Type A, Type B, combined and expanded measurement uncertainty, according to the Guide to the Expression of Uncertainty in Measurement, is proposed.
{"title":"Metrological evaluation of computer-based electrical power quality signal generator","authors":"Z. Kokolanski, V. Dimcev, D. Taskovski, M. Simić, D. Denic, Jelena Eordevic-Kozarov","doi":"10.1109/EUROCON.2017.8011230","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011230","url":null,"abstract":"Metrological evaluation of electrical power quality signal generator, designed for reproducing the standard power quality disturbances, is presented in this paper. This generator is functionally based on the virtual instrumentation software, data acquisition card and power amplifier for scaling the output voltage to the nominal power line voltage level (230 V). The realized computer-based signal generator can be used as suitable and cost effective alternative to the various instruments for testing the power quality meters and analyzers. Metrological assessment of signal generator includes calculation of measurement uncertainty components and final presentation of measurement uncertainty budget. Procedure for calculation of Type A, Type B, combined and expanded measurement uncertainty, according to the Guide to the Expression of Uncertainty in Measurement, is proposed.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128827598","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011153
G. Alkady, M. Rentschler, R. Daoud, H. Amer, Hadeer Ahmed, Hassan H. Halawa
Recently, FPGA-based NCS applications have been widely used. Industrial environments have a lot of electromagnetic interference which may induce transient and permanent faults. As a result, Fault-Tolerant FPGA based NCS applications are required. In this paper, an NCS model composed of a combination of S2A architecture and In-Loop architecture connected to each other through Ethernet switch, is described. The S2A part of the model is an FPGA-based video sensor network which requires protection against transient faults. Several Fault-Tolerant techniques are mentioned in the literature for protection. Two Fault-Tolerant techniques are under study which are Hot Standby and Sift-Out. The fault model used is Single Event Upsets (SEUs). Dynamic Partial Recovery is used. Markov Models are used for reliability calculations. Results show that even though the Sift-Out technique is more reliable than Hot Standby, there may be situations where the difference in reliability cannot justify the extra cost.
{"title":"FPGA-based reliable video sensor in NC","authors":"G. Alkady, M. Rentschler, R. Daoud, H. Amer, Hadeer Ahmed, Hassan H. Halawa","doi":"10.1109/EUROCON.2017.8011153","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011153","url":null,"abstract":"Recently, FPGA-based NCS applications have been widely used. Industrial environments have a lot of electromagnetic interference which may induce transient and permanent faults. As a result, Fault-Tolerant FPGA based NCS applications are required. In this paper, an NCS model composed of a combination of S2A architecture and In-Loop architecture connected to each other through Ethernet switch, is described. The S2A part of the model is an FPGA-based video sensor network which requires protection against transient faults. Several Fault-Tolerant techniques are mentioned in the literature for protection. Two Fault-Tolerant techniques are under study which are Hot Standby and Sift-Out. The fault model used is Single Event Upsets (SEUs). Dynamic Partial Recovery is used. Markov Models are used for reliability calculations. Results show that even though the Sift-Out technique is more reliable than Hot Standby, there may be situations where the difference in reliability cannot justify the extra cost.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133856969","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011094
Chuncan Deng, Cheng Yang, Fangyong Xiao, Dajie Suolang, Wenshan She
In order to improve the technical level of the grid state operation, the ant colony algorithm based on dynamic updating is proposed for the massive signal analysis in grid state system with the complexity of the structure and the high reliability. Though data mining and updating in dynamic correlation rules of device monitoring signals with evolutionary genetic algorithm, the correlation analysis of device signals is realized; and then through the dynamic ant colony algorithm grid signal location and analysis technology, the device monitoring signal accurate semantic extraction and expression is achieved. Through the massive signal analysis and reading test, the validity of the signal correlation judgment and signal file expression analysis is verified.
{"title":"Accurate recognition and extraction of massive device monitoring signals based on dynamic updating of genetic ant colony algorithm","authors":"Chuncan Deng, Cheng Yang, Fangyong Xiao, Dajie Suolang, Wenshan She","doi":"10.1109/EUROCON.2017.8011094","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011094","url":null,"abstract":"In order to improve the technical level of the grid state operation, the ant colony algorithm based on dynamic updating is proposed for the massive signal analysis in grid state system with the complexity of the structure and the high reliability. Though data mining and updating in dynamic correlation rules of device monitoring signals with evolutionary genetic algorithm, the correlation analysis of device signals is realized; and then through the dynamic ant colony algorithm grid signal location and analysis technology, the device monitoring signal accurate semantic extraction and expression is achieved. Through the massive signal analysis and reading test, the validity of the signal correlation judgment and signal file expression analysis is verified.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115224290","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011095
Bojan Kostadinov, M. Jovanov, E. Stankov
Uptime is very important with any computer system, because a solution which is not available cannot be relied upon to provide accurate information in a timely and routine manner — usually resulting in the loss of time, revenue, or data. Highly-available systems and websites rely on eliminating single points of failure, and on reacting quickly to any network, hardware or software issues which may occur. In this paper, we present a cost-effective website failover solution, based on using a Content Delivery Network as a proxy, and asynchronous replication of data across servers hosted on distant locations. We outline several scenarios where this approach is favorable to load balancers, failover IP addresses, and other solutions currently used to design highly-available systems. At the end, we present a case study where we show the dramatic reduce of expenses with the proposed solution.
{"title":"Cost-effective website failover through a CDN network and asynchronous replication","authors":"Bojan Kostadinov, M. Jovanov, E. Stankov","doi":"10.1109/EUROCON.2017.8011095","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011095","url":null,"abstract":"Uptime is very important with any computer system, because a solution which is not available cannot be relied upon to provide accurate information in a timely and routine manner — usually resulting in the loss of time, revenue, or data. Highly-available systems and websites rely on eliminating single points of failure, and on reacting quickly to any network, hardware or software issues which may occur. In this paper, we present a cost-effective website failover solution, based on using a Content Delivery Network as a proxy, and asynchronous replication of data across servers hosted on distant locations. We outline several scenarios where this approach is favorable to load balancers, failover IP addresses, and other solutions currently used to design highly-available systems. At the end, we present a case study where we show the dramatic reduce of expenses with the proposed solution.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114683353","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011218
Gorazd Berginc, U. Rudež, R. Mihalic
Since the first Phasor Measurement Units in Slovenian electricity transmission system operator's (ELES) grid have been put in operation in 2005, the number of installed units has grown considerably. In addition, in recent years, connections have been established with grid operators from Switzerland, Denmark, Italy, Germany, Montenegro and Austria with the purpose of exchanging available measurement data from these units. Besides recorded real-time phasor measurements being helpful during post-mortem analyses the trend is to extend the current functionality of the entire measurement system from mere visualization and observation towards more sophisticated smart and automatized decision-making tool applying advanced mathematical algorithms. The introduction of these special functions is expected to be applied gradually and conservatively. Nevertheless, the final target is to include smart control of special devices as well such as phase-shifting transformer and Static Var Compensation units as a countermeasure to prevent system-wide oscillations in the Europe's continental interconnection.
{"title":"WAMS upgrade in the Slovenian power system current status and plans for the future","authors":"Gorazd Berginc, U. Rudež, R. Mihalic","doi":"10.1109/EUROCON.2017.8011218","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011218","url":null,"abstract":"Since the first Phasor Measurement Units in Slovenian electricity transmission system operator's (ELES) grid have been put in operation in 2005, the number of installed units has grown considerably. In addition, in recent years, connections have been established with grid operators from Switzerland, Denmark, Italy, Germany, Montenegro and Austria with the purpose of exchanging available measurement data from these units. Besides recorded real-time phasor measurements being helpful during post-mortem analyses the trend is to extend the current functionality of the entire measurement system from mere visualization and observation towards more sophisticated smart and automatized decision-making tool applying advanced mathematical algorithms. The introduction of these special functions is expected to be applied gradually and conservatively. Nevertheless, the final target is to include smart control of special devices as well such as phase-shifting transformer and Static Var Compensation units as a countermeasure to prevent system-wide oscillations in the Europe's continental interconnection.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123206739","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011186
L. Lopacinski, K. KrishneGowda
The main aspect considered in this paper is a comparison of interleaver sizes for convolutional and low-density parity-check codes (LDPC) employed for 100 Gbps wireless communication at 240 GHz with parallel sequence spread spectrum (PSSS). Interleavers required for PSSS-15 and convolutional codes are larger in silicon area than a complete Reed-Solomon decoder. Thus, convolutional codes are not recommended for the targeted application. LDPC codes require 10x smaller interleavers than convolutional codes and seem to be a good choice for the targeted data rate. Alternatively, interleaved Reed-Solomon decoders are proposed. Hard decision RS decoding reduces the size of the targeted forward error correction processor and provides error correction performance not lower than hard decision convolutional codes at the same code rate.
{"title":"Towards 100 Gbps wireless communication: Investigation of FEC interleavers for PSSS-15 spreading","authors":"L. Lopacinski, K. KrishneGowda","doi":"10.1109/EUROCON.2017.8011186","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011186","url":null,"abstract":"The main aspect considered in this paper is a comparison of interleaver sizes for convolutional and low-density parity-check codes (LDPC) employed for 100 Gbps wireless communication at 240 GHz with parallel sequence spread spectrum (PSSS). Interleavers required for PSSS-15 and convolutional codes are larger in silicon area than a complete Reed-Solomon decoder. Thus, convolutional codes are not recommended for the targeted application. LDPC codes require 10x smaller interleavers than convolutional codes and seem to be a good choice for the targeted data rate. Alternatively, interleaved Reed-Solomon decoders are proposed. Hard decision RS decoding reduces the size of the targeted forward error correction processor and provides error correction performance not lower than hard decision convolutional codes at the same code rate.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"54 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123217529","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 : 2017-07-01DOI: 10.1109/EUROCON.2017.8011116
M. Daković, L. Stanković, B. Lutovac, I. Stanković
Rounding error in the discrete Fourier transform calculated with fast fixed-point algorithms is considered. It is shown that the variance of the rounding error depends on frequency index. Theoretically obtained results for error variance are statistically checked on decimation-in-time fast Fourier transform with two rounding methods.
{"title":"On the fixed-point rounding in the DFT","authors":"M. Daković, L. Stanković, B. Lutovac, I. Stanković","doi":"10.1109/EUROCON.2017.8011116","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011116","url":null,"abstract":"Rounding error in the discrete Fourier transform calculated with fast fixed-point algorithms is considered. It is shown that the variance of the rounding error depends on frequency index. Theoretically obtained results for error variance are statistically checked on decimation-in-time fast Fourier transform with two rounding methods.","PeriodicalId":114100,"journal":{"name":"IEEE EUROCON 2017 -17th International Conference on Smart Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129506803","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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