Pub Date : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216235
A. Sherstneva, O. Sherstneva
The article presents a two-level algorithm for call processing inside telecommunication system. The algorithm is based on data from a monitoring system. Features of system functioning takes into account the vectorization of calls and based on dynamic routing method. The algorithm considers the main technological processes of call service. A mathematical model is developed for telecommunication systems with two levels of call processing. Few formulas are obtained to evaluate performance guidelines in terms of customers and managers. The article aims to introduce such parameters as degree of service satisfaction, intensity of call service, post processing time of a call. Analytical dependencies between statistics information and key performance indicators inside system are presented. The article shows in graphic form dependency of post processing call time and probability of loss calls.
{"title":"Modelling the Functioning of Infocommunication System","authors":"A. Sherstneva, O. Sherstneva","doi":"10.1109/UralCon49858.2020.9216235","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216235","url":null,"abstract":"The article presents a two-level algorithm for call processing inside telecommunication system. The algorithm is based on data from a monitoring system. Features of system functioning takes into account the vectorization of calls and based on dynamic routing method. The algorithm considers the main technological processes of call service. A mathematical model is developed for telecommunication systems with two levels of call processing. Few formulas are obtained to evaluate performance guidelines in terms of customers and managers. The article aims to introduce such parameters as degree of service satisfaction, intensity of call service, post processing time of a call. Analytical dependencies between statistics information and key performance indicators inside system are presented. The article shows in graphic form dependency of post processing call time and probability of loss calls.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116029847","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}
The article presents the results of multifactorial experiments on the influence of dissimilar environmental factors and the value of stray currents on the corrosive state of substation grounding devices elements of various types and purposes. Based on the results of the experiments, a mathematical model of the grounding devices corrosion process has been developed. Mathematical modeling by applying the regression coefficients of the second order regression equation, which allow calculating the corrosion state of the grounding devices elements with a low error is performed. To assess the adequacy of the developed model, the results of comparing experimental data with calculated values with an error of no more than 19% are presented. Using the developed mathematical models of the corrosion process of grounding elements, three-dimensional graphical models were constructed using the Mathcad computer program, which represents the dependence of the mass loss of metal used for the manufacture of grounding electrodes and changes to the current spreading resistance of grounding devices on the soil humidity and the value of stray currents.
{"title":"Mathematical Modeling of the Grounding Devices Corrosion Process","authors":"Ilkhom Abdulloev, Bakhtiyor Abdulloev, Nekkadam Odinaev","doi":"10.1109/UralCon49858.2020.9216305","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216305","url":null,"abstract":"The article presents the results of multifactorial experiments on the influence of dissimilar environmental factors and the value of stray currents on the corrosive state of substation grounding devices elements of various types and purposes. Based on the results of the experiments, a mathematical model of the grounding devices corrosion process has been developed. Mathematical modeling by applying the regression coefficients of the second order regression equation, which allow calculating the corrosion state of the grounding devices elements with a low error is performed. To assess the adequacy of the developed model, the results of comparing experimental data with calculated values with an error of no more than 19% are presented. Using the developed mathematical models of the corrosion process of grounding elements, three-dimensional graphical models were constructed using the Mathcad computer program, which represents the dependence of the mass loss of metal used for the manufacture of grounding electrodes and changes to the current spreading resistance of grounding devices on the soil humidity and the value of stray currents.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"18 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120822077","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216302
R. Sarakhanova, M. Zharkov
The article presents method of higher harmonic components compensation in the output voltage spectrum of the starter-generator system of the aircraft operating in the electric power generation mode. A mathematical model of the starter-generator system is proposed. The equivalent circuit of the system with current feedback of the voltage source inverter (VSI) and with load voltage feedback is presented. The equations for calculating output voltage for the investigated system are derived. The characteristic of the amplitude of the higher harmonics of the output voltage versus VSI transfer factor characteristic is obtained. The output voltage spectrum and the cycloconverter current spectrum when the VSI is turned on in parallel are presented. The output voltage total harmonic distortion when the VSI is turned on in parallel is determined.
{"title":"Method of Higher Harmonic Components Compensation in the Output Voltage Spectrum of the Starter-Generator System of the Aircraft","authors":"R. Sarakhanova, M. Zharkov","doi":"10.1109/UralCon49858.2020.9216302","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216302","url":null,"abstract":"The article presents method of higher harmonic components compensation in the output voltage spectrum of the starter-generator system of the aircraft operating in the electric power generation mode. A mathematical model of the starter-generator system is proposed. The equivalent circuit of the system with current feedback of the voltage source inverter (VSI) and with load voltage feedback is presented. The equations for calculating output voltage for the investigated system are derived. The characteristic of the amplitude of the higher harmonics of the output voltage versus VSI transfer factor characteristic is obtained. The output voltage spectrum and the cycloconverter current spectrum when the VSI is turned on in parallel are presented. The output voltage total harmonic distortion when the VSI is turned on in parallel is determined.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130993062","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216307
Ibrahim Alwazah, R. Nasyrov, R. Aljendy
The development in the electricity sector continues on the world level, as well as in the Syrian Arab Republic, regardless of the instability that the country has been experiencing since 2011. Therefore, it is necessary to search for methods that will plug the deficit in electrical energy when it is present on the one hand and improve the quality of electrical energy on the other hand. In this research, simulation models of the 400 kV high voltage network were presented in the Syrian Arab Republic. This model is considered the first step in assessing the technical state of the grid and knowing its ability to connect with solar energy sources planned to be built in Syria in the future in addition to connecting with global networks (DESERTEC) for example. This paper addressed the analysis of load flow, the measurement of modal / eigenvalues, transient stabilization cases and short-circuit effects on the power system generating units. The DIgSILENT program (PowerFactory simulation program) was used to design the network and perform the calculations.
{"title":"Analysis of the Performance of Syrian 400kV Electrical Network","authors":"Ibrahim Alwazah, R. Nasyrov, R. Aljendy","doi":"10.1109/UralCon49858.2020.9216307","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216307","url":null,"abstract":"The development in the electricity sector continues on the world level, as well as in the Syrian Arab Republic, regardless of the instability that the country has been experiencing since 2011. Therefore, it is necessary to search for methods that will plug the deficit in electrical energy when it is present on the one hand and improve the quality of electrical energy on the other hand. In this research, simulation models of the 400 kV high voltage network were presented in the Syrian Arab Republic. This model is considered the first step in assessing the technical state of the grid and knowing its ability to connect with solar energy sources planned to be built in Syria in the future in addition to connecting with global networks (DESERTEC) for example. This paper addressed the analysis of load flow, the measurement of modal / eigenvalues, transient stabilization cases and short-circuit effects on the power system generating units. The DIgSILENT program (PowerFactory simulation program) was used to design the network and perform the calculations.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129220938","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216282
V. Golov, A. Kalutskov, D. Kormilitsyn
Nowadays the Russian electric power system as the biggest power net in the world has problems with synchronization of the remote areas with the basic electrical system. Moreover, the industrial development and growth in the number of consumers require an increase of existing lines transmission capacity. The construction of new power transmission lines causes high economic costs. The huge amount of researches figured out that the installation of controlled series compensation devices at long-distance power transmission lines with voltage of 500 kV and higher is able to significantly increase the transmission capacity of the power transmission line and increase the level of stability. The aim of this paper is to investigate the effects of the series compensation devices installed on 220 kV lines on stability and the current load of system elements. In this regard, it is advisable to analyze the aperiodic steady-state stability of an electric power system containing 220 kV power lines and issues of improving the transmission capacity of the power transmission lines.
{"title":"Controlled Series Compensation of High Voltage Lines to Increase Transmission Capacity","authors":"V. Golov, A. Kalutskov, D. Kormilitsyn","doi":"10.1109/UralCon49858.2020.9216282","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216282","url":null,"abstract":"Nowadays the Russian electric power system as the biggest power net in the world has problems with synchronization of the remote areas with the basic electrical system. Moreover, the industrial development and growth in the number of consumers require an increase of existing lines transmission capacity. The construction of new power transmission lines causes high economic costs. The huge amount of researches figured out that the installation of controlled series compensation devices at long-distance power transmission lines with voltage of 500 kV and higher is able to significantly increase the transmission capacity of the power transmission line and increase the level of stability. The aim of this paper is to investigate the effects of the series compensation devices installed on 220 kV lines on stability and the current load of system elements. In this regard, it is advisable to analyze the aperiodic steady-state stability of an electric power system containing 220 kV power lines and issues of improving the transmission capacity of the power transmission lines.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126231822","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216267
R. Minullin, Yuriy V. Piskovatskiy, V. Kasimov
The paper considers simulation model of a linear radio-frequency path of overhead power line implemented in the PSCAD software environment, which allows studying the propagation of location signals along the overhead power line conductors in 6–10 kV distribution circuits in terms of single phase to earth faults occurrence. Model and corresponding time domain reflectometer trace recorded in laboratory and field conditions for overhead power lines when simulating various types of single phase to earth faults are compared. The methods of location based determination of the single phase to earth faults distance and location on the conductors are given. The results of model and experimental studies in cases of single phase to earth faults show high convergence and performance of model and experimental time domain reflectometer traces of the 6–10 kV line, which indicates the representativeness of the developed model and the possibility of its use in location-based monitoring of 6–10 kV overhead lines.
{"title":"Model and Experimental Detection of Single Phase-to-Earth Faults of Overhead Conductors in 6–10 Kv Distribution Circuits by a Location Method","authors":"R. Minullin, Yuriy V. Piskovatskiy, V. Kasimov","doi":"10.1109/UralCon49858.2020.9216267","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216267","url":null,"abstract":"The paper considers simulation model of a linear radio-frequency path of overhead power line implemented in the PSCAD software environment, which allows studying the propagation of location signals along the overhead power line conductors in 6–10 kV distribution circuits in terms of single phase to earth faults occurrence. Model and corresponding time domain reflectometer trace recorded in laboratory and field conditions for overhead power lines when simulating various types of single phase to earth faults are compared. The methods of location based determination of the single phase to earth faults distance and location on the conductors are given. The results of model and experimental studies in cases of single phase to earth faults show high convergence and performance of model and experimental time domain reflectometer traces of the 6–10 kV line, which indicates the representativeness of the developed model and the possibility of its use in location-based monitoring of 6–10 kV overhead lines.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125919430","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216277
A. M. Gataullin
From the point of view intelligent energy supply systems development, it is important to have reliable methods and equipment for extract reliable information about the condition of insulators of high-voltage electrical equipment by the method of partial discharges (PDs). It is important to compare the characteristics of PDs at DC and AC applied voltage using electromagnetic sensor (EMS) and a contact sensor (CS), since the characteristics of PDs are well known at constant applied voltage using CD, and extract the diagnostic information from noise signals. Electromagnetic registration method of the PDs is most promising for that. In present paper a method of recording PD by the non-contact methods using electromagnetic (EMD) and contact sensor (CS) describes. To separate the PDs from the corona the amplitude-phase diagrams (AFD) of PDs distribution by using the data conditioner system based on National Instruments equipment and the Lab View graphic programming program was calculated. The characteristics of PDs obtained using EMD are in good agreement with the characteristics of PDs obtained using CS.
{"title":"High Voltage Electrical Insulators Diagnostics by Partial Discharges Characteristics","authors":"A. M. Gataullin","doi":"10.1109/UralCon49858.2020.9216277","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216277","url":null,"abstract":"From the point of view intelligent energy supply systems development, it is important to have reliable methods and equipment for extract reliable information about the condition of insulators of high-voltage electrical equipment by the method of partial discharges (PDs). It is important to compare the characteristics of PDs at DC and AC applied voltage using electromagnetic sensor (EMS) and a contact sensor (CS), since the characteristics of PDs are well known at constant applied voltage using CD, and extract the diagnostic information from noise signals. Electromagnetic registration method of the PDs is most promising for that. In present paper a method of recording PD by the non-contact methods using electromagnetic (EMD) and contact sensor (CS) describes. To separate the PDs from the corona the amplitude-phase diagrams (AFD) of PDs distribution by using the data conditioner system based on National Instruments equipment and the Lab View graphic programming program was calculated. The characteristics of PDs obtained using EMD are in good agreement with the characteristics of PDs obtained using CS.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125266388","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216287
P. Rashitov, Dmitry V. Mostovoy, D. Seregin
Large variations of voltage at consumers from the nominal value and voltages asymmetry in four-wire distribution networks have led to the development of devices for improvement of power supply in these networks. The problem of using a booster to improve the quality of power supply in four-wire electric networks of rural areas and the private sector is shown. A new device is proposed - a booster balancer. Analytical and mathematical models of voltage-boosting devices have been developed. A comparative analysis of three devices for improvement of power supply in four-wire distribution networks of rural areas and inner suburbs. This analysis showed the advantages of the new device.
{"title":"Comparative Analysis of Devices for Improvement Quality of Power Supply in 0.38 kV Distribution Networks in Rural Area and Inner Suburbs","authors":"P. Rashitov, Dmitry V. Mostovoy, D. Seregin","doi":"10.1109/UralCon49858.2020.9216287","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216287","url":null,"abstract":"Large variations of voltage at consumers from the nominal value and voltages asymmetry in four-wire distribution networks have led to the development of devices for improvement of power supply in these networks. The problem of using a booster to improve the quality of power supply in four-wire electric networks of rural areas and the private sector is shown. A new device is proposed - a booster balancer. Analytical and mathematical models of voltage-boosting devices have been developed. A comparative analysis of three devices for improvement of power supply in four-wire distribution networks of rural areas and inner suburbs. This analysis showed the advantages of the new device.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131551535","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216274
I. Lvovich, A. Preobrazhenskiy, O. Choporov
The paper discusses the possibilities of control distributed energy systems. The scheme of a control system over a distributed electric network section to ensure load uniformity is demonstrated. The main functions of its components are indicated. The development of an optimization model and load balancing algorithm in an electric network section is carried out. The results are obtained demonstrated the distribution of power among the consumers. The dependence of iterations from the number of consumers of electric energy under consideration when using the algorithm is shown. The results may be useful for the developers of distributed electrical systems with the required characteristics of balanced loads.
{"title":"Modeling Consumer Load Control in Distributed Electrical Networks","authors":"I. Lvovich, A. Preobrazhenskiy, O. Choporov","doi":"10.1109/UralCon49858.2020.9216274","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216274","url":null,"abstract":"The paper discusses the possibilities of control distributed energy systems. The scheme of a control system over a distributed electric network section to ensure load uniformity is demonstrated. The main functions of its components are indicated. The development of an optimization model and load balancing algorithm in an electric network section is carried out. The results are obtained demonstrated the distribution of power among the consumers. The dependence of iterations from the number of consumers of electric energy under consideration when using the algorithm is shown. The results may be useful for the developers of distributed electrical systems with the required characteristics of balanced loads.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127771245","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 : 2020-09-01DOI: 10.1109/UralCon49858.2020.9216238
A. Nikolaev, P. Tulupov, V. Ivekeev
In the framework of this study, the requirements for the functionality of modern electric control systems that provide for the optimal operation of electric arc furnaces (EAF) and ladle-furnaces (LF) at minimum cost have been defined. This analysis is necessary to solve a wide range of practical problems associated with the planning of electric steelmaking, as well as the choice of a supplier of basic process equipment. The analysis of material necessary for the solution of this problem in modern conditions is particularly relevant, because in some cases, based on the results of research aimed at optimizing the operation of furnace units, there is no technical possibility of releasing the identified energy reserve due to restrictions imposed by the architecture of the electrical control system.
{"title":"Comparative Analysis of Modern Electric Control Systems of Electric Arc Furnaces","authors":"A. Nikolaev, P. Tulupov, V. Ivekeev","doi":"10.1109/UralCon49858.2020.9216238","DOIUrl":"https://doi.org/10.1109/UralCon49858.2020.9216238","url":null,"abstract":"In the framework of this study, the requirements for the functionality of modern electric control systems that provide for the optimal operation of electric arc furnaces (EAF) and ladle-furnaces (LF) at minimum cost have been defined. This analysis is necessary to solve a wide range of practical problems associated with the planning of electric steelmaking, as well as the choice of a supplier of basic process equipment. The analysis of material necessary for the solution of this problem in modern conditions is particularly relevant, because in some cases, based on the results of research aimed at optimizing the operation of furnace units, there is no technical possibility of releasing the identified energy reserve due to restrictions imposed by the architecture of the electrical control system.","PeriodicalId":230353,"journal":{"name":"2020 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132682646","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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