Pub Date : 2019-10-01DOI: 10.1109/URALCON.2019.8877622
L. German, A. Serebryakov, V. Osokin
The description of the three-stage filter-compensating installation (FCI) in the traction AC network with voltage of 25 kV is given. The first stage-sequential inclusion of three LC sections is activated at low and medium loads, the second stage-sequential inclusion of two LC one LC section - at loads greater than the average and the third stage - one LC section - when driving heavy trains. The proposed installation allows providing a given capacity of the railway and reducing power losses in the traction network. When shunting FCI sections with thyristor switches, it is recommended to turn them on in order to reduce the current and voltage surges in the maximum current of the corresponding section. On the positions of the partitioning filter-compensating installation must be performed adjustable with 2–3 levels of power. It is desirable to commute switches, shunt FCI sections, while using the thyristor. In case of three-step FCI, it is advisable to design a traction network 6 – 9 MVAr for posts partition with the average reactive load. Commuting a section of the filter compensating unit should be shorted at zero voltage on the capacitor and the maximum current.
{"title":"Three-stage Filter Compensating Installation of Traction Network of Alternating Current","authors":"L. German, A. Serebryakov, V. Osokin","doi":"10.1109/URALCON.2019.8877622","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877622","url":null,"abstract":"The description of the three-stage filter-compensating installation (FCI) in the traction AC network with voltage of 25 kV is given. The first stage-sequential inclusion of three LC sections is activated at low and medium loads, the second stage-sequential inclusion of two LC one LC section - at loads greater than the average and the third stage - one LC section - when driving heavy trains. The proposed installation allows providing a given capacity of the railway and reducing power losses in the traction network. When shunting FCI sections with thyristor switches, it is recommended to turn them on in order to reduce the current and voltage surges in the maximum current of the corresponding section. On the positions of the partitioning filter-compensating installation must be performed adjustable with 2–3 levels of power. It is desirable to commute switches, shunt FCI sections, while using the thyristor. In case of three-step FCI, it is advisable to design a traction network 6 – 9 MVAr for posts partition with the average reactive load. Commuting a section of the filter compensating unit should be shorted at zero voltage on the capacitor and the maximum current.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125359084","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877686
S. Shovkoplyas, D.A. Chernomaz, E. Satsuk
The relevance of the topic of preventing ice-wind accidents in electrical networks is noted, and a feature of the organization of the ice melting system on extra high voltage (EHV) overhead transmission lines (OHL) is shown. The existing technical solutions for ice melting schemes on the phase wires and lightning protection rope of EHV OHL are listed, while problems are noted in covering the entire length of the circuit or in a specific local area in the middle of the route. Technical solutions are proposed for ice melting schemes on phase wires and lightning protection ropes of EHV OHL taking into account the latest achievements, in particular: the use of a high voltage thyristor ice melting switch on phase wires, thereby fully automating the process, application of the method of heating lightning protection ropes induced by currents from the phase operating currents (direct sequence), in the mode of power transmission over EHV OHL.
{"title":"Ensuring Reliable Operation of Electrical Network During ice Formation on Extra High Voltage Transmission Lines","authors":"S. Shovkoplyas, D.A. Chernomaz, E. Satsuk","doi":"10.1109/URALCON.2019.8877686","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877686","url":null,"abstract":"The relevance of the topic of preventing ice-wind accidents in electrical networks is noted, and a feature of the organization of the ice melting system on extra high voltage (EHV) overhead transmission lines (OHL) is shown. The existing technical solutions for ice melting schemes on the phase wires and lightning protection rope of EHV OHL are listed, while problems are noted in covering the entire length of the circuit or in a specific local area in the middle of the route. Technical solutions are proposed for ice melting schemes on phase wires and lightning protection ropes of EHV OHL taking into account the latest achievements, in particular: the use of a high voltage thyristor ice melting switch on phase wires, thereby fully automating the process, application of the method of heating lightning protection ropes induced by currents from the phase operating currents (direct sequence), in the mode of power transmission over EHV OHL.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125522851","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877643
O. Nos, Ekaterina E. Abramushkina, S. Kharitonov
At most FACTS (Flexible AC Transmission System) applications, grid-connected photovoltaic systems, power conditioning and etc., for a proper operation and a synchronization with a power utility it is necessary to have an actual information about a phase angle or a fundamental frequency of three-phase grid voltages. For these purposes a special phase-locked loop (PLL) is used, which estimates the voltage quantities for a reference phase signal generation synchronized with the AC transmission line. A control design procedure of the PLL with a proportional-integral and a proportional-integral-derivative controller types under balanced and sinusoidal conditions of a grid, as well as a PLL-based algorithm control design under a grid fault operating condition with the voltage variations is briefly addressed by the report. Simulation results in the MATLAB/Simulink environment show that the proposed PLL control strategy can provide the fast dynamic response and be used under the harmonic distortions as well.
{"title":"Control Design of Fast Response PLL for FACTS Applications","authors":"O. Nos, Ekaterina E. Abramushkina, S. Kharitonov","doi":"10.1109/URALCON.2019.8877643","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877643","url":null,"abstract":"At most FACTS (Flexible AC Transmission System) applications, grid-connected photovoltaic systems, power conditioning and etc., for a proper operation and a synchronization with a power utility it is necessary to have an actual information about a phase angle or a fundamental frequency of three-phase grid voltages. For these purposes a special phase-locked loop (PLL) is used, which estimates the voltage quantities for a reference phase signal generation synchronized with the AC transmission line. A control design procedure of the PLL with a proportional-integral and a proportional-integral-derivative controller types under balanced and sinusoidal conditions of a grid, as well as a PLL-based algorithm control design under a grid fault operating condition with the voltage variations is briefly addressed by the report. Simulation results in the MATLAB/Simulink environment show that the proposed PLL control strategy can provide the fast dynamic response and be used under the harmonic distortions as well.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128993524","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877682
M. Popov, N. G. Pavlov, D. Petrushin
Background The paper has a multilateral description of asynchronous operation, and aims to improve automatic protective devices. A mathematical model of processes is developed by synthesis and control of generalized analytical signals by using data record of complex values. This made it possible to estimate automatics for elimination of asynchronous operation in the coordinate system and formulate requirements for automatics to avoid loss of generator excitation and prevent quasi-stable asynchronous operation development. Materials and methods: A realization of filter of summarized analytical signals of voltage and current is used in the paper. The method is based on Hilbert transform and coordinate-system transformation. Results: An operating characteristic of two-stage automatics for elimination of asynchronous operation is described. Conclusions: A method of improvement for modern automatics for elimination of asynchronous operation is proposed.
{"title":"Modern Automatics for Elimination of Asynchronous Operation","authors":"M. Popov, N. G. Pavlov, D. Petrushin","doi":"10.1109/URALCON.2019.8877682","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877682","url":null,"abstract":"Background The paper has a multilateral description of asynchronous operation, and aims to improve automatic protective devices. A mathematical model of processes is developed by synthesis and control of generalized analytical signals by using data record of complex values. This made it possible to estimate automatics for elimination of asynchronous operation in the coordinate system and formulate requirements for automatics to avoid loss of generator excitation and prevent quasi-stable asynchronous operation development. Materials and methods: A realization of filter of summarized analytical signals of voltage and current is used in the paper. The method is based on Hilbert transform and coordinate-system transformation. Results: An operating characteristic of two-stage automatics for elimination of asynchronous operation is described. Conclusions: A method of improvement for modern automatics for elimination of asynchronous operation is proposed.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"277 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116437821","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877611
E. Omelchenko, A. Beliy, I. Kozhevnikov
Transient processes of an induction motor stator current and voltage were registered by the digital protection device for a direct start and an idling regimes. The calculation algorithm was presented and instantaneous values of an active and reactive power, power losses, the magnetization curve, the main inductance of the motor and magnetic steel losses were calculated. The specified values were calculated on the induction motor computer model and the results of the experimental and simulated data were compared. The space-time wave MMF is built at idle according to the database of stator winding currents and magnetic core parameters. The resulting wave allows estimating the arisen high-frequency oscillations of the MMF in the gap between the stator and the rotor of the motor.
{"title":"Electric Drive System Study in Scientific and Educational Center “Schneider Electric - Nosov Magnitogorsk State Technical University”","authors":"E. Omelchenko, A. Beliy, I. Kozhevnikov","doi":"10.1109/URALCON.2019.8877611","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877611","url":null,"abstract":"Transient processes of an induction motor stator current and voltage were registered by the digital protection device for a direct start and an idling regimes. The calculation algorithm was presented and instantaneous values of an active and reactive power, power losses, the magnetization curve, the main inductance of the motor and magnetic steel losses were calculated. The specified values were calculated on the induction motor computer model and the results of the experimental and simulated data were compared. The space-time wave MMF is built at idle according to the database of stator winding currents and magnetic core parameters. The resulting wave allows estimating the arisen high-frequency oscillations of the MMF in the gap between the stator and the rotor of the motor.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127399480","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877654
A. M. Gataullin
The paper presents the main on-line technologies for insulators technical condition assessment in smart grid power supply systems, based on partial discharges characteristics analyses. The mechanism of solid insulation breakdown, caused by partial discharges, is described. A newly developed method of technical condition estimating of high voltage insulators had been compared with the traditional methods: the method of determining the ohmic resistance by a megger and the method of breakdown voltage. Furthermore, the method for separate recognition of PDs on the surface of polymer insulators from internal PDs is developed. The developed technology can be used for self-diagnosis of intelligent power supply systems.
{"title":"Insulators Electrical Strength Estimation under AC Applied Voltage","authors":"A. M. Gataullin","doi":"10.1109/URALCON.2019.8877654","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877654","url":null,"abstract":"The paper presents the main on-line technologies for insulators technical condition assessment in smart grid power supply systems, based on partial discharges characteristics analyses. The mechanism of solid insulation breakdown, caused by partial discharges, is described. A newly developed method of technical condition estimating of high voltage insulators had been compared with the traditional methods: the method of determining the ohmic resistance by a megger and the method of breakdown voltage. Furthermore, the method for separate recognition of PDs on the surface of polymer insulators from internal PDs is developed. The developed technology can be used for self-diagnosis of intelligent power supply systems.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125893682","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877668
V. Polyakov, I. Plotnikov, N. Postnikov
A mathematical model of the frequency converter power part with a PWM inverter and energy storage device with a DC/DC converter is given. The models of PWM inverter and DC/DC converter are based on the continuous approximation principle of switching functions. Single-loop, double-loop and three-loop types of control systems for energy storage devices are considered. The structures and parameters of controllers were obtained by the synthesis method of subordinate control systems with a modular optimum tuning. The research aim is to identify the static and dynamic properties of control systems with an energy storage device as a part of an electric drive operating in the intermittent mode. The simulation results and comparative estimation of the control systems characteristics are given. The results can be useful in the development of control systems for energy storage devices.
{"title":"Comparative Analysis of DC/DC Converter Control Systems for Variable-Frequency Drives with Supercapacitors","authors":"V. Polyakov, I. Plotnikov, N. Postnikov","doi":"10.1109/URALCON.2019.8877668","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877668","url":null,"abstract":"A mathematical model of the frequency converter power part with a PWM inverter and energy storage device with a DC/DC converter is given. The models of PWM inverter and DC/DC converter are based on the continuous approximation principle of switching functions. Single-loop, double-loop and three-loop types of control systems for energy storage devices are considered. The structures and parameters of controllers were obtained by the synthesis method of subordinate control systems with a modular optimum tuning. The research aim is to identify the static and dynamic properties of control systems with an energy storage device as a part of an electric drive operating in the intermittent mode. The simulation results and comparative estimation of the control systems characteristics are given. The results can be useful in the development of control systems for energy storage devices.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"122 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114154405","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877617
E. Danilina, V. Astakhov
This paper discusses several methods to reduce the eddy current energy losses in a working area of the vortex-layer devices. Using a known mathematical model numerical experiments were carried out to evaluate effectiveness, to identify and analyze all the advantages and disadvantages for each of the proposed methods. The calculation results are presented as graphs of the dependences of the energy losses on the working area shell thickness and on the frequency of the field inductors; as graphs of the distribution eddy current flow function along the working area shell length with the varying field frequency; as graphs of the distribution primary magnetic field and shell reaction field on the symmetry axis. It was established that for the three-inductor vortex-layer device addition of two equally spaced orthogonal cuts in the working area shell leads to a 43% energy losses reduction, and an alternating configuration of the inductors gives a reduction from 20% to 29% depending on the connection method.
{"title":"Methods for Eddy Current Energy Losses Reduction in Vortex-Layer Devices","authors":"E. Danilina, V. Astakhov","doi":"10.1109/URALCON.2019.8877617","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877617","url":null,"abstract":"This paper discusses several methods to reduce the eddy current energy losses in a working area of the vortex-layer devices. Using a known mathematical model numerical experiments were carried out to evaluate effectiveness, to identify and analyze all the advantages and disadvantages for each of the proposed methods. The calculation results are presented as graphs of the dependences of the energy losses on the working area shell thickness and on the frequency of the field inductors; as graphs of the distribution eddy current flow function along the working area shell length with the varying field frequency; as graphs of the distribution primary magnetic field and shell reaction field on the symmetry axis. It was established that for the three-inductor vortex-layer device addition of two equally spaced orthogonal cuts in the working area shell leads to a 43% energy losses reduction, and an alternating configuration of the inductors gives a reduction from 20% to 29% depending on the connection method.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130739357","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877661
V. Naumov, V. Antonov, N. Ivanov
The faults in AC network may cause commutation failure in adjacent inverter station of HVDC, accompanied by injection of DC line discharge current into AC network. In this case a significant number of transient components arises in emergency voltages and currents, which level is comparable with level of main harmonic. Conventional protection relays may miss-operate due to error in non-adaptive orthogonal component filters during processing of such signals. The implementation of adaptive signal processing algorithms for improving relay protection stability is studied. It's shown that improving of signal recognition require proper sampling rate and adaptive signal model order. An adaptive blocking algorithm preventing protection miss-operation in poor measurement conditions is suggested.
{"title":"Information Component Recognition in Fault Signals for Relay Protection of Electric Grids with HVDC","authors":"V. Naumov, V. Antonov, N. Ivanov","doi":"10.1109/URALCON.2019.8877661","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877661","url":null,"abstract":"The faults in AC network may cause commutation failure in adjacent inverter station of HVDC, accompanied by injection of DC line discharge current into AC network. In this case a significant number of transient components arises in emergency voltages and currents, which level is comparable with level of main harmonic. Conventional protection relays may miss-operate due to error in non-adaptive orthogonal component filters during processing of such signals. The implementation of adaptive signal processing algorithms for improving relay protection stability is studied. It's shown that improving of signal recognition require proper sampling rate and adaptive signal model order. An adaptive blocking algorithm preventing protection miss-operation in poor measurement conditions is suggested.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133812126","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 : 2019-10-01DOI: 10.1109/URALCON.2019.8877616
K. V. Arzhanov
The paper presents the results of the development of the energy efficient photovoltaic solar tracking system considering the wind load. Authors propose the algorithm and the tracking model with stepper motors, which provide the energy efficiency as well as smooth and continuous operating of solar panel tracking under the random impacts including the wind load. The modes of operation of the Electromechanical actuator, allowing one to increase the survivability and reliability of the system under the action of wind load. The authors present the results of calculating a trajectory of movement depending on various influence of wind loading is resulted - helps to move, prevents to move, does not influence movement. The question of reducing the power consumption of stepper motors in the tracking mode and the absence of movement is considered. The proposed scheme with a non-linear setpoint speed enabling the crossing of transients in the control loop of the amplitude of the current. The study of the dynamic characteristics of the electromechanical tracking system with a stepper motor, shows the influence of the load on the characteristics of the tracking system in the presence of variable moment of inertia in the mechanical parts of the system.
{"title":"Tracking Autonomous Photovoltaic Installations for Sun under Action of Wind Load","authors":"K. V. Arzhanov","doi":"10.1109/URALCON.2019.8877616","DOIUrl":"https://doi.org/10.1109/URALCON.2019.8877616","url":null,"abstract":"The paper presents the results of the development of the energy efficient photovoltaic solar tracking system considering the wind load. Authors propose the algorithm and the tracking model with stepper motors, which provide the energy efficiency as well as smooth and continuous operating of solar panel tracking under the random impacts including the wind load. The modes of operation of the Electromechanical actuator, allowing one to increase the survivability and reliability of the system under the action of wind load. The authors present the results of calculating a trajectory of movement depending on various influence of wind loading is resulted - helps to move, prevents to move, does not influence movement. The question of reducing the power consumption of stepper motors in the tracking mode and the absence of movement is considered. The proposed scheme with a non-linear setpoint speed enabling the crossing of transients in the control loop of the amplitude of the current. The study of the dynamic characteristics of the electromechanical tracking system with a stepper motor, shows the influence of the load on the characteristics of the tracking system in the presence of variable moment of inertia in the mechanical parts of the system.","PeriodicalId":277973,"journal":{"name":"2019 International Ural Conference on Electrical Power Engineering (UralCon)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127540933","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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