Pub Date : 2023-11-06DOI: 10.24425/aee.2022.141679
: Large synchronous generators are of high importance for the stability of power systems. They generate the frequency of the system and stabilize it in case of severe grid faults like trips of large in-feeders or loads. In distributed energy systems, in-feed via inverters will replace this generation in large parts. Modern inverters are capable of supporting grid frequency during severe faults by different means on the one hand. On the other hand, higher Rates of Change of Frequency (RoCoF) after incidents need to be accustomed by future systems. To be able to analyse the RoCoF withstand capability of synchronous or induction generators, suitable models need to be developed. Especially the control and excitation system model need enhancements compared to models proposed in standards like IEEE Std 421.5. This paper elaborates on the necessary modelling depth and validates the approach with example results.
{"title":"Modelling of synchronous generators for the analysis of frequency transients above 1 Hz/s","authors":"","doi":"10.24425/aee.2022.141679","DOIUrl":"https://doi.org/10.24425/aee.2022.141679","url":null,"abstract":": Large synchronous generators are of high importance for the stability of power systems. They generate the frequency of the system and stabilize it in case of severe grid faults like trips of large in-feeders or loads. In distributed energy systems, in-feed via inverters will replace this generation in large parts. Modern inverters are capable of supporting grid frequency during severe faults by different means on the one hand. On the other hand, higher Rates of Change of Frequency (RoCoF) after incidents need to be accustomed by future systems. To be able to analyse the RoCoF withstand capability of synchronous or induction generators, suitable models need to be developed. Especially the control and excitation system model need enhancements compared to models proposed in standards like IEEE Std 421.5. This paper elaborates on the necessary modelling depth and validates the approach with example results.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"462 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637122","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 : 2023-11-06DOI: 10.24425/aee.2022.141673
Yang Li, Przemysław Janik, Harald Schwarz, Klaus Pfeiffer
: This paper provides a method for simplified description of a regional power grid model aimed to deliver a grid reduction, and improve grid performance observability. The derived power grid model can be used to analyze the regional allocation of the decentralized energy generation and consumption. The expansion of wind and solar generation in the power system affects the residual load. The power balance between electricity consumption and generation was calculated and analyzed based on the temporal and spatial scales. The proposed grid clustering method is a useful approach for performance analysis in systems with a growing share of renewable generation.
{"title":"Proposal of a regional grid cluster model for analysis of electrical power network performance","authors":"Yang Li, Przemysław Janik, Harald Schwarz, Klaus Pfeiffer","doi":"10.24425/aee.2022.141673","DOIUrl":"https://doi.org/10.24425/aee.2022.141673","url":null,"abstract":": This paper provides a method for simplified description of a regional power grid model aimed to deliver a grid reduction, and improve grid performance observability. The derived power grid model can be used to analyze the regional allocation of the decentralized energy generation and consumption. The expansion of wind and solar generation in the power system affects the residual load. The power balance between electricity consumption and generation was calculated and analyzed based on the temporal and spatial scales. The proposed grid clustering method is a useful approach for performance analysis in systems with a growing share of renewable generation.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"8 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544644","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 : 2023-11-06DOI: 10.24425/aee.2022.141683
Jin Li, Mai Lu
: The objective of this work is to evaluate the safety of adult and child passengers exposed to a radio frequency (RF) source, i.e., a leaky coaxial cable (LCX) on the subway platform. An adult model, a child model, and a LCX model have been numerically designed in COMSOL Multiphysics software. The distributions of the induced electric field ( E -field), specific absorption rate (SAR), magnetic field ( H -field) and the head temperature increase in adult and child passenger models were calculated at 900 MHz. The induced fields in the passengers were compared with that without screen doors. The results show that the E -field, SAR and H -field in the whole body of the child are 2 . 00 × 10 − 2 V/m, 1 . 07 × 10 − 7 W/kg, and 2 . 94 × 10 − 4 A/m, respectively. The E -field, SAR and H -field in the central nervous system of the child are 1 . 00 × 10 − 2 V/m, 2 . 44 × 10 − 8 W/kg, and 2 . 41 × 10 − 4 A/m, respectively. The maximum values of the E -field, SAR and H -field in the adult passenger are 1.49–2.34 times higher than those of the child. The E -field, SAR, and H -field in the passenger models without a screen door are larger than those with a screen door. The screen door has a partial shielding effect on the RF electromagnetic field. The values of the maximum temperature that increases in adult and child head tissue are 0.2114 and 0.2111 ◦ C after waiting 6 minutes exposure, respectively. All calculated results are well below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits for general public exposure, indicating that RF electromagnetic exposure caused by the LCX on the subway platform is not a threat to passenger’s health.
{"title":"Safety assessment of electromagnetic exposure for adult and child passengers standing on the subway platform","authors":"Jin Li, Mai Lu","doi":"10.24425/aee.2022.141683","DOIUrl":"https://doi.org/10.24425/aee.2022.141683","url":null,"abstract":": The objective of this work is to evaluate the safety of adult and child passengers exposed to a radio frequency (RF) source, i.e., a leaky coaxial cable (LCX) on the subway platform. An adult model, a child model, and a LCX model have been numerically designed in COMSOL Multiphysics software. The distributions of the induced electric field ( E -field), specific absorption rate (SAR), magnetic field ( H -field) and the head temperature increase in adult and child passenger models were calculated at 900 MHz. The induced fields in the passengers were compared with that without screen doors. The results show that the E -field, SAR and H -field in the whole body of the child are 2 . 00 × 10 − 2 V/m, 1 . 07 × 10 − 7 W/kg, and 2 . 94 × 10 − 4 A/m, respectively. The E -field, SAR and H -field in the central nervous system of the child are 1 . 00 × 10 − 2 V/m, 2 . 44 × 10 − 8 W/kg, and 2 . 41 × 10 − 4 A/m, respectively. The maximum values of the E -field, SAR and H -field in the adult passenger are 1.49–2.34 times higher than those of the child. The E -field, SAR, and H -field in the passenger models without a screen door are larger than those with a screen door. The screen door has a partial shielding effect on the RF electromagnetic field. The values of the maximum temperature that increases in adult and child head tissue are 0.2114 and 0.2111 ◦ C after waiting 6 minutes exposure, respectively. All calculated results are well below the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits for general public exposure, indicating that RF electromagnetic exposure caused by the LCX on the subway platform is not a threat to passenger’s health.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"17 36","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135545568","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 : 2023-11-06DOI: 10.24425/aee.2022.141685
{"title":"Influence of conductive particle contaminationon the insulation system of rotating electrical machines with direct oil cooling","authors":"","doi":"10.24425/aee.2022.141685","DOIUrl":"https://doi.org/10.24425/aee.2022.141685","url":null,"abstract":"","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"438 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637140","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 : 2023-11-06DOI: 10.24425/aee.2022.141678
Isaiah Adebayo, Yanxia Sun
{"title":"New approaches for the identification of influential and critical nodes in an electric grid","authors":"Isaiah Adebayo, Yanxia Sun","doi":"10.24425/aee.2022.141678","DOIUrl":"https://doi.org/10.24425/aee.2022.141678","url":null,"abstract":"","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"14 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544600","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 : 2023-11-06DOI: 10.24425/aee.2022.141677
Viet-Hung Dang, Abderrahmane Beroual, Pawel Rozga
: This article deals with the analysis of the fractal dimension of streamers propagating in mineral oil, under lightning impulse voltage, using the box counting method; the method and technique of calculation are described therein. In the considered experimental conditions, the average velocities of recorded streamers are of 2.4 km/s and 1.8 km/s for positive and negative streamers, respectively; these velocities correspond to the 2 nd mode of streamers propagation. It is shown that the streamers present the fractal dimension 𝐷 ; and the higher 𝐷 is the bushier are the streamers (i
{"title":"Fractal dimensions analysis of branching streamers propagating in mineral oil","authors":"Viet-Hung Dang, Abderrahmane Beroual, Pawel Rozga","doi":"10.24425/aee.2022.141677","DOIUrl":"https://doi.org/10.24425/aee.2022.141677","url":null,"abstract":": This article deals with the analysis of the fractal dimension of streamers propagating in mineral oil, under lightning impulse voltage, using the box counting method; the method and technique of calculation are described therein. In the considered experimental conditions, the average velocities of recorded streamers are of 2.4 km/s and 1.8 km/s for positive and negative streamers, respectively; these velocities correspond to the 2 nd mode of streamers propagation. It is shown that the streamers present the fractal dimension 𝐷 ; and the higher 𝐷 is the bushier are the streamers (i","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"2 32","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135584385","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 : 2023-11-06DOI: 10.24425/aee.2022.141675
: This article provides an optimized solution to the problem of passive shielding against static magnetic fields with any number of spherical shells. It is known, that the shielding factor of a layered structure increases in contrast to a single shell with the same overall thickness. For the reduction of weight and cost by given material parameters and available space the best system for the layer positions has to be found. Because classic magnetically shielded rooms are very heavy, this system will be used to develop a trans-portable Zero-Gauss-Chamber. To handle this problem, a new way was developed, in which for the first time the solution with regard to shielding and weight was optimized. Therefore, a solution for the most general case of spherical shells was chosen with an adapted boundary condition. This solution was expanded to an arbitrary number of layers and permeabilities. With this analytic solution a differential evolution algorithm is able to find the best partition of the shells. These optimized solutions are verified by numerical solutions made by the Finite Element Method (FEM). After that the solutions of different raw data are determined and investigated.
{"title":"Novel optimization method for mobile magnetostatic shield and test applications","authors":"","doi":"10.24425/aee.2022.141675","DOIUrl":"https://doi.org/10.24425/aee.2022.141675","url":null,"abstract":": This article provides an optimized solution to the problem of passive shielding against static magnetic fields with any number of spherical shells. It is known, that the shielding factor of a layered structure increases in contrast to a single shell with the same overall thickness. For the reduction of weight and cost by given material parameters and available space the best system for the layer positions has to be found. Because classic magnetically shielded rooms are very heavy, this system will be used to develop a trans-portable Zero-Gauss-Chamber. To handle this problem, a new way was developed, in which for the first time the solution with regard to shielding and weight was optimized. Therefore, a solution for the most general case of spherical shells was chosen with an adapted boundary condition. This solution was expanded to an arbitrary number of layers and permeabilities. With this analytic solution a differential evolution algorithm is able to find the best partition of the shells. These optimized solutions are verified by numerical solutions made by the Finite Element Method (FEM). After that the solutions of different raw data are determined and investigated.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"501 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135637404","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 : 2023-11-06DOI: 10.24425/aee.2022.141674
: With the extinction of fossil fuels and high increase in power demand, the necessity for renewable energy power generation has increased globally. Solar PV is one such renewable energy power generation, widely used these days in the power sector. The inverters used for power conversion suffer from power losses in the switching elements. This paper aims at the detailed analysis on switching losses in these inverters and also aims at increasing the efficiency of the inverter by reducing losses. Losses in these power electronic switches vary with their types. In this analysis the most widely used semiconductor switches like the insulated gate bipolar transistor (IGBT) and metal oxide semiconductor field effect transistor (MOSFET) are compared. Also using the sinusoidal pulse width modulation (SPWM) technique, improves the system efficiency considerably. Two SPWM-based single-phase inverters with the IGBT and MOSFET are designed and simulated in a MATLAB Simulink environment. The voltage drop and, thereby, the power loss across the switches are compared and analysed. The proposed technique shows that the SPWM inverter with the IGBT has lower power loss than the SPWM inverter with the MOSFET.
{"title":"Modelling and simulation of sinusoidal pulse width modulation controller for solar photovoltaic inverter to minimize the switching losses and improving the system efficiency","authors":"","doi":"10.24425/aee.2022.141674","DOIUrl":"https://doi.org/10.24425/aee.2022.141674","url":null,"abstract":": With the extinction of fossil fuels and high increase in power demand, the necessity for renewable energy power generation has increased globally. Solar PV is one such renewable energy power generation, widely used these days in the power sector. The inverters used for power conversion suffer from power losses in the switching elements. This paper aims at the detailed analysis on switching losses in these inverters and also aims at increasing the efficiency of the inverter by reducing losses. Losses in these power electronic switches vary with their types. In this analysis the most widely used semiconductor switches like the insulated gate bipolar transistor (IGBT) and metal oxide semiconductor field effect transistor (MOSFET) are compared. Also using the sinusoidal pulse width modulation (SPWM) technique, improves the system efficiency considerably. Two SPWM-based single-phase inverters with the IGBT and MOSFET are designed and simulated in a MATLAB Simulink environment. The voltage drop and, thereby, the power loss across the switches are compared and analysed. The proposed technique shows that the SPWM inverter with the IGBT has lower power loss than the SPWM inverter with the MOSFET.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"44 7","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135633927","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 : 2023-11-06DOI: 10.24425/aee.2022.141676
Murtadha Al-Kaabi, Jaleel Al Hasheme, Layth Al-Bahrani
: This article presents a new efficient optimization technique namely the Multi-Objective Improved Differential Evolution Algorithm (MOIDEA) to solve the multi-objective optimal power flow problem in power systems. The main features of the Differential Evolution (DE) algorithm are simple, easy, and efficient, but sometimes, it is prone to stagnation in the local optima. This paper has proposed many improvements, in the exploration and exploitation processes, to enhance the performance of DE for solving optimal power flow (OPF) problems. The main contributions of the DE algorithm are i) the crossover rate will be changing randomly and continuously for each iteration, ii) all probabilities that have been ignored in the crossover process have been taken, and iii) in selection operation, the mathematical calculations of the mutation process have been taken. Four conflicting objective functions simultaneously have been applied to select the Pareto optimal front for the multi-objective OPF. Fuzzy set theory has been used to extract the best compromise solution. These objective functions that have been considered for setting control variables of the power system are total fuel cost (TFC), total emission (TE), real power losses (RPL), and voltage profile (VP) improvement. The IEEE 30-bus standard system has been used to validate the effectiveness and superiority of the approach proposed based on MATLAB software. Finally, to demonstrate the effectiveness and capability of the MOIDEA, the results obtained by this method will be compared with other recent methods
{"title":"Improved Differential Evolution Algorithm to solve multi-objective of optimal power flow problem","authors":"Murtadha Al-Kaabi, Jaleel Al Hasheme, Layth Al-Bahrani","doi":"10.24425/aee.2022.141676","DOIUrl":"https://doi.org/10.24425/aee.2022.141676","url":null,"abstract":": This article presents a new efficient optimization technique namely the Multi-Objective Improved Differential Evolution Algorithm (MOIDEA) to solve the multi-objective optimal power flow problem in power systems. The main features of the Differential Evolution (DE) algorithm are simple, easy, and efficient, but sometimes, it is prone to stagnation in the local optima. This paper has proposed many improvements, in the exploration and exploitation processes, to enhance the performance of DE for solving optimal power flow (OPF) problems. The main contributions of the DE algorithm are i) the crossover rate will be changing randomly and continuously for each iteration, ii) all probabilities that have been ignored in the crossover process have been taken, and iii) in selection operation, the mathematical calculations of the mutation process have been taken. Four conflicting objective functions simultaneously have been applied to select the Pareto optimal front for the multi-objective OPF. Fuzzy set theory has been used to extract the best compromise solution. These objective functions that have been considered for setting control variables of the power system are total fuel cost (TFC), total emission (TE), real power losses (RPL), and voltage profile (VP) improvement. The IEEE 30-bus standard system has been used to validate the effectiveness and superiority of the approach proposed based on MATLAB software. Finally, to demonstrate the effectiveness and capability of the MOIDEA, the results obtained by this method will be compared with other recent methods","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135544645","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 : 2023-11-06DOI: 10.24425/aee.2022.141670
Ling Liu, Jinsong Zhang
: The discrete Fourier transform (DFT) is a principal method for power system harmonic analysis. The fundamental frequency of the power system increases or decreases following load changes during normal operation. It is difficult to achieve synchronous sampling and integer period truncation in power harmonic analysis. The resulting spectrum leakage affects the accuracy of the measurement results. For this reason, a windowed interpolation DFT method for power system harmonic analysis to reduce errors was presented in this paper. First, the frequency domain expression of the windowed signal Fourier transform is analyzed. Then, the magnitude of the three discrete spectrum lines near the harmonic frequency point is used to determine the accurate position of the harmonic spectrum. Then, the calculation of the amplitude, frequency, and phase of harmonics is presented. The triple-line interpolation DFT can improve the accuracy of electrical harmonic analysis. Based on the algorithm, the practical rectification formulas were obtained by using the polynomial approximation method. The simulation results show that the fast attenuation of window function sidelobe is the key to reduce the error. The triple-line interpolation DFT based on Hanning, Blackman, Nuttall 3-Term windows has higher calculation accuracy, which can meet the requirements of electrical harmonic analysis.
{"title":"An approach to power system harmonic analysis based on triple-line interpolation discrete Fourier transform","authors":"Ling Liu, Jinsong Zhang","doi":"10.24425/aee.2022.141670","DOIUrl":"https://doi.org/10.24425/aee.2022.141670","url":null,"abstract":": The discrete Fourier transform (DFT) is a principal method for power system harmonic analysis. The fundamental frequency of the power system increases or decreases following load changes during normal operation. It is difficult to achieve synchronous sampling and integer period truncation in power harmonic analysis. The resulting spectrum leakage affects the accuracy of the measurement results. For this reason, a windowed interpolation DFT method for power system harmonic analysis to reduce errors was presented in this paper. First, the frequency domain expression of the windowed signal Fourier transform is analyzed. Then, the magnitude of the three discrete spectrum lines near the harmonic frequency point is used to determine the accurate position of the harmonic spectrum. Then, the calculation of the amplitude, frequency, and phase of harmonics is presented. The triple-line interpolation DFT can improve the accuracy of electrical harmonic analysis. Based on the algorithm, the practical rectification formulas were obtained by using the polynomial approximation method. The simulation results show that the fast attenuation of window function sidelobe is the key to reduce the error. The triple-line interpolation DFT based on Hanning, Blackman, Nuttall 3-Term windows has higher calculation accuracy, which can meet the requirements of electrical harmonic analysis.","PeriodicalId":45464,"journal":{"name":"Archives of Electrical Engineering","volume":"15 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135545583","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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