Pub Date : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059184
O. Adonyev, V. Izhutkin
This article presents the results of the development of the S-band transceiver module. A series of measurements of the X-parameters of high-power S-band amplifier was carried out. The results of comparing the computer simulation of S-band amplifier based on the compact model and measured X-parameters are presented. The results of computer simulation and measurements of the devices included in the transmitting path, the main technical characteristics of the transmitting path of the developed transceiver module are presented.
{"title":"Development of Broadband Transceiver Module for S-band Antenna Array using mathematical model of X-parameters: Transmission Path","authors":"O. Adonyev, V. Izhutkin","doi":"10.1109/REEPE49198.2020.9059184","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059184","url":null,"abstract":"This article presents the results of the development of the S-band transceiver module. A series of measurements of the X-parameters of high-power S-band amplifier was carried out. The results of comparing the computer simulation of S-band amplifier based on the compact model and measured X-parameters are presented. The results of computer simulation and measurements of the devices included in the transmitting path, the main technical characteristics of the transmitting path of the developed transceiver module are presented.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122638027","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059096
M. Purdin, Denis Ksenok
In this paper, we present a mathematical model and a numerical simulation technique based on boundary layer theory for a developing low-amplitude pulsating laminar flow in a flat channel. The calculation results were obtained and the analysis of influence of the pulsating flow on the hydraulic and friction resistances was carried out. At pulsation amplitudes of more than 2/3 of the average cross-sectional velocity, the transverse component of velocity begins to affect the flow. The relations between the changes in the coefficients of both hydraulic resistance and friction resistance are presented and analyzed. Over the entire settling length, while increasing the dimensionless pulsation frequency, the pulsation amplitude of the hydraulic resistance coefficient increases much more compared to the friction resistance coefficient. The dependences of the amplitude and phase of the resistance pulsations are presented, which make it possible to restore their initial values.
{"title":"Resistance in a Developing Low-Amplitude Pulsating Laminar Flow in a Flat Channel","authors":"M. Purdin, Denis Ksenok","doi":"10.1109/REEPE49198.2020.9059096","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059096","url":null,"abstract":"In this paper, we present a mathematical model and a numerical simulation technique based on boundary layer theory for a developing low-amplitude pulsating laminar flow in a flat channel. The calculation results were obtained and the analysis of influence of the pulsating flow on the hydraulic and friction resistances was carried out. At pulsation amplitudes of more than 2/3 of the average cross-sectional velocity, the transverse component of velocity begins to affect the flow. The relations between the changes in the coefficients of both hydraulic resistance and friction resistance are presented and analyzed. Over the entire settling length, while increasing the dimensionless pulsation frequency, the pulsation amplitude of the hydraulic resistance coefficient increases much more compared to the friction resistance coefficient. The dependences of the amplitude and phase of the resistance pulsations are presented, which make it possible to restore their initial values.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"515 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132720192","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059118
Borbad G. Mirzoevich, Murodbek S. Kholnazarovich, Ismoil O. Nazrimadovich, Rajabbek O. Ayombekovich
At present time, the introduction of digital technologies has a significant impact on the building principles of modern electrical substations. Thereby it is provided an increasing interest to the standards of the IEC 61850 series. The paper provides a comparative analysis of traditional busbar protections and options for their modern implementation carried out with the application of IEC 61850 standard. The digital model of DPBP capable of working with modern digital CTs according to the protocols of the standard family IEC 61850 has been developed.
{"title":"Review of Modern Methods for Busbar Protection Implementation","authors":"Borbad G. Mirzoevich, Murodbek S. Kholnazarovich, Ismoil O. Nazrimadovich, Rajabbek O. Ayombekovich","doi":"10.1109/REEPE49198.2020.9059118","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059118","url":null,"abstract":"At present time, the introduction of digital technologies has a significant impact on the building principles of modern electrical substations. Thereby it is provided an increasing interest to the standards of the IEC 61850 series. The paper provides a comparative analysis of traditional busbar protections and options for their modern implementation carried out with the application of IEC 61850 standard. The digital model of DPBP capable of working with modern digital CTs according to the protocols of the standard family IEC 61850 has been developed.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"631 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123959153","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059202
V. Tupov, A. Taratorin
Article analyzes the influence of the combined heat and power plant (CHP) equipment structure on the size of sanitary protection zone (SPZ) by noise factor. Analyze realized in relation to different climatic conditions. The differences between calculation of sanitary protection zone by noise factor and pollutants air emissions have been shown. The calculation results of semiempirical theory and calculations results by computer technology with different types and structure of operating equipment were compared. The conditions when the results of calculation of SPZ differ are shown. The results of climatic conditions influence on the width of sanitary protection zones are presented. Changes of width of SPZ for climatic conditions of Moscow are given. Obtained results allow to select noise reduction measures more accurate and cost-effective.
{"title":"Influence of Thermal Power Plants Equipment Structure on the Size of Sanitary Protection Zone by Noise Factor","authors":"V. Tupov, A. Taratorin","doi":"10.1109/REEPE49198.2020.9059202","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059202","url":null,"abstract":"Article analyzes the influence of the combined heat and power plant (CHP) equipment structure on the size of sanitary protection zone (SPZ) by noise factor. Analyze realized in relation to different climatic conditions. The differences between calculation of sanitary protection zone by noise factor and pollutants air emissions have been shown. The calculation results of semiempirical theory and calculations results by computer technology with different types and structure of operating equipment were compared. The conditions when the results of calculation of SPZ differ are shown. The results of climatic conditions influence on the width of sanitary protection zones are presented. Changes of width of SPZ for climatic conditions of Moscow are given. Obtained results allow to select noise reduction measures more accurate and cost-effective.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129332910","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059151
A. Shcherbakova, G. Shvedov, Ivan A. Morsin
The article presents the results of a study of the power consumption of a multi-storey residential building with gas stoves. The dependence of the consumed electricity on the area of apartments and the number of residents is analyzed. The objective of the study is to consider the trend in energy consumption for various cases and determine the amount of consumption per person, depending on the area of the apartment in which he lives. The purpose of the work is to compare the standards of electricity consumption for a given region and real consumption per person, depending on the number of rooms in the apartment and the number of residents. To accomplish this task, the directions of probability theory are used, associated with the determination of the characteristics of random variables and the analysis of regression dependencies between them.
{"title":"Power Consumption of Typical Apartments of Multi-Storey Residential Buildings","authors":"A. Shcherbakova, G. Shvedov, Ivan A. Morsin","doi":"10.1109/REEPE49198.2020.9059151","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059151","url":null,"abstract":"The article presents the results of a study of the power consumption of a multi-storey residential building with gas stoves. The dependence of the consumed electricity on the area of apartments and the number of residents is analyzed. The objective of the study is to consider the trend in energy consumption for various cases and determine the amount of consumption per person, depending on the area of the apartment in which he lives. The purpose of the work is to compare the standards of electricity consumption for a given region and real consumption per person, depending on the number of rooms in the apartment and the number of residents. To accomplish this task, the directions of probability theory are used, associated with the determination of the characteristics of random variables and the analysis of regression dependencies between them.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128851873","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059113
A. Matasov, A. Cherkasov, D. Kholodny, I. Mikhaylov
The paper considers the behavior of a Cooper pair in the potential field of an Abrikosov vortex, describes the process physics qualitatively. An estimate of the characteristic length and energy of the system is made on the basis of the Heisenberg uncertainty and the quasiclassical method. A comparison is made of the theoretical and experimental coherence lengths for cuprate superconductors, and good agreement is obtained for the estimates for many cuprate superconductors. The results obtained can be used to build a complete theory of superconductivity, to be a starting point for building a theory of the dynamics of a superconducting system, which will entail, in particular, a description of the current-voltage characteristics of superconductors of the second kind.
{"title":"Cooper Pair in the Potential Field of Abrikosov Vortex","authors":"A. Matasov, A. Cherkasov, D. Kholodny, I. Mikhaylov","doi":"10.1109/REEPE49198.2020.9059113","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059113","url":null,"abstract":"The paper considers the behavior of a Cooper pair in the potential field of an Abrikosov vortex, describes the process physics qualitatively. An estimate of the characteristic length and energy of the system is made on the basis of the Heisenberg uncertainty and the quasiclassical method. A comparison is made of the theoretical and experimental coherence lengths for cuprate superconductors, and good agreement is obtained for the estimates for many cuprate superconductors. The results obtained can be used to build a complete theory of superconductivity, to be a starting point for building a theory of the dynamics of a superconducting system, which will entail, in particular, a description of the current-voltage characteristics of superconductors of the second kind.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115785221","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059190
S. Salem, K. Fraňa, I. Nová, J. Erhart
Nowadays, much attention is directed towards raising the efficiency of energy consumption in different life applications. One example of the work done to pursue this goal is Acoustic Energy Harvesting, AEH. This paper provides an overview of Acoustic Energy Harvesting using the technology of Piezo-Electricity as well as the components of an acoustic energy harvester. It also demonstrates work done to study acoustic energy harvesting using a cylindrical Piezo-element made of Penta-Zirconate Titanate, PZT-5A. The work presented here aims at defining the electrical properties of the cylinder by measuring its impedance properties using a Precision Impedance Analyzer. The cylinder was found to have a capacitive effect over the audible frequency range. The obtained impedance values shall help match the impedance of the cylinder, the electric energy source, to the impedance of the load circuit that will make use of the harvested energy.
{"title":"Acoustic Energy Harvesting Using Piezo-Electric Materials","authors":"S. Salem, K. Fraňa, I. Nová, J. Erhart","doi":"10.1109/REEPE49198.2020.9059190","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059190","url":null,"abstract":"Nowadays, much attention is directed towards raising the efficiency of energy consumption in different life applications. One example of the work done to pursue this goal is Acoustic Energy Harvesting, AEH. This paper provides an overview of Acoustic Energy Harvesting using the technology of Piezo-Electricity as well as the components of an acoustic energy harvester. It also demonstrates work done to study acoustic energy harvesting using a cylindrical Piezo-element made of Penta-Zirconate Titanate, PZT-5A. The work presented here aims at defining the electrical properties of the cylinder by measuring its impedance properties using a Precision Impedance Analyzer. The cylinder was found to have a capacitive effect over the audible frequency range. The obtained impedance values shall help match the impedance of the cylinder, the electric energy source, to the impedance of the load circuit that will make use of the harvested energy.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126056774","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059132
K. V. Sterkhov, D. A. Khokhlov, M. N. Zaichenko, K. Pleshanov
Article describes the actuality of High-Pressurized Heat Recovery Steam Generator (HPHRSG) with the gas turbine combined cycle realization for existing steam-power unit reconstruction. It is shown that this is relevant not only because it formally meets the requirements of the energy development program, but also allows reducing of reconstruction costs due to the equipment parts preservation. Proposed layout differences from the existing solutions in this area are given. It was shown that the optimal pressure in HPHRSG is 4–5 bar, and this is associated with the largest incensement in heat transfer coefficient. It is shown that the greatest decrease in metal consumption occurs in the same area. Several calculated modernization schemes for the popular T-100 and K-300 steam turbines with domestic gas turbines GTE-160 and GT-25PA are presented. It is related to incensement of equipment unification degree. Several promising schemes for implementation are proposed.
{"title":"Thermal Scheme Development for Combined Cycle Power Plant with High-Pressurized Heat Recovery Steam Generator","authors":"K. V. Sterkhov, D. A. Khokhlov, M. N. Zaichenko, K. Pleshanov","doi":"10.1109/REEPE49198.2020.9059132","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059132","url":null,"abstract":"Article describes the actuality of High-Pressurized Heat Recovery Steam Generator (HPHRSG) with the gas turbine combined cycle realization for existing steam-power unit reconstruction. It is shown that this is relevant not only because it formally meets the requirements of the energy development program, but also allows reducing of reconstruction costs due to the equipment parts preservation. Proposed layout differences from the existing solutions in this area are given. It was shown that the optimal pressure in HPHRSG is 4–5 bar, and this is associated with the largest incensement in heat transfer coefficient. It is shown that the greatest decrease in metal consumption occurs in the same area. Several calculated modernization schemes for the popular T-100 and K-300 steam turbines with domestic gas turbines GTE-160 and GT-25PA are presented. It is related to incensement of equipment unification degree. Several promising schemes for implementation are proposed.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131311592","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059225
R. Safiullin, I. Yangirov
The paper presents the original design of the tachogenerator-accelerometer (TA) with increased capabilities. Analytical relations are given for the analysis and design of the original rotor with and without edge effects, in the presence of longitudinal slits with a bevel in the hollow rotor, depending on the low resonance frequencies (LRF). Electromagnetic processes in electromagnetic accelerometers are described by Maxwell's equations for slowly moving isotropic and conductive media. The peculiarity of the accelerometer operation is that when the rotor rotates at a certain constant speed, the resulting variable magnetic flux (due to the transverse reaction of the rotor), coupled to the measuring winding, induces an EMF proportional to the angular velocity of the rotor. This allows the accelerometer to work as a tachogenerator-unlike a standard accelerometer with a smooth hollow rotor that only measures angular acceleration. Due to its multi-functionality and improved metrological characteristics, this TA can be used in instrumentation and power engineering.
{"title":"Tachogenerator for processing Signals and Data from Electrical Machine","authors":"R. Safiullin, I. Yangirov","doi":"10.1109/REEPE49198.2020.9059225","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059225","url":null,"abstract":"The paper presents the original design of the tachogenerator-accelerometer (TA) with increased capabilities. Analytical relations are given for the analysis and design of the original rotor with and without edge effects, in the presence of longitudinal slits with a bevel in the hollow rotor, depending on the low resonance frequencies (LRF). Electromagnetic processes in electromagnetic accelerometers are described by Maxwell's equations for slowly moving isotropic and conductive media. The peculiarity of the accelerometer operation is that when the rotor rotates at a certain constant speed, the resulting variable magnetic flux (due to the transverse reaction of the rotor), coupled to the measuring winding, induces an EMF proportional to the angular velocity of the rotor. This allows the accelerometer to work as a tachogenerator-unlike a standard accelerometer with a smooth hollow rotor that only measures angular acceleration. Due to its multi-functionality and improved metrological characteristics, this TA can be used in instrumentation and power engineering.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"486 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120897493","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 : 2020-03-01DOI: 10.1109/REEPE49198.2020.9059237
R. Ipanov, A. Komarov, Nikita Luchkovskiy
The disadvantage of existing ground penetrating radars (GPR) is that the probing is local in nature from the earth's surface, or, when exploring glaciers, probing is carried out using helicopter-based GPRs mounted on a special platform, which affects the system's performance and increases economic costs. The best solution for air-based GPRs is to use unmanned aerial vehicle (UAV) for their installation. In this work, for a GPR onboard of an UAV, a probing phase-code shift keyed (generally polyphase) signal is synthesized with an extremely low level of side lobes and a sufficiently large base for realizing the required energy potential of the GPR. A comparative analysis of the correlation characteristics of binary and three-phase probing signals (PS) is carried out.
{"title":"Phase-Code Shift Keyed Probing Signals with Zero Autocorrelation Zone for Ground Penetrating Radar Onboard of Unmanned Aerial Vehicle","authors":"R. Ipanov, A. Komarov, Nikita Luchkovskiy","doi":"10.1109/REEPE49198.2020.9059237","DOIUrl":"https://doi.org/10.1109/REEPE49198.2020.9059237","url":null,"abstract":"The disadvantage of existing ground penetrating radars (GPR) is that the probing is local in nature from the earth's surface, or, when exploring glaciers, probing is carried out using helicopter-based GPRs mounted on a special platform, which affects the system's performance and increases economic costs. The best solution for air-based GPRs is to use unmanned aerial vehicle (UAV) for their installation. In this work, for a GPR onboard of an UAV, a probing phase-code shift keyed (generally polyphase) signal is synthesized with an extremely low level of side lobes and a sufficiently large base for realizing the required energy potential of the GPR. A comparative analysis of the correlation characteristics of binary and three-phase probing signals (PS) is carried out.","PeriodicalId":142369,"journal":{"name":"2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133084727","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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