Pub Date : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803441
A. Zgank
This paper proposes an approach, how to speed up the acoustic classification of bee swarm activity. The proposed system could be used as a daily monitoring solution for beehives, especially if they are located remotely. Recorded audio signal was used for acoustic classification with the Mel-frequency cepstral coefficients and hidden Markov acoustic models. The research objective was to analyze the influence of the reduced number of feature extraction coefficients on classification accuracy and real-time factor. Experiments were carried out with the Open Source Beehives Project audio recordings. The baseline system achieved 86,00% classification accuracy. The optimal acoustic classification system with 6 Mel-frequency cepstral coefficients achieved 85.38% accuracy and a 22.1% speed improvement over the baseline system.
{"title":"Reduced MFCC Feature Extraction Dimension for Acoustic Classification of Bee Swarm Activity","authors":"A. Zgank","doi":"10.1109/ELEKTRO53996.2022.9803441","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803441","url":null,"abstract":"This paper proposes an approach, how to speed up the acoustic classification of bee swarm activity. The proposed system could be used as a daily monitoring solution for beehives, especially if they are located remotely. Recorded audio signal was used for acoustic classification with the Mel-frequency cepstral coefficients and hidden Markov acoustic models. The research objective was to analyze the influence of the reduced number of feature extraction coefficients on classification accuracy and real-time factor. Experiments were carried out with the Open Source Beehives Project audio recordings. The baseline system achieved 86,00% classification accuracy. The optimal acoustic classification system with 6 Mel-frequency cepstral coefficients achieved 85.38% accuracy and a 22.1% speed improvement over the baseline system.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133891674","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803342
M. Frivaldský, J. Šedo, P. Resutík, B. Hanko
The article is dealing withi the issue related to the multilevel inverter (MLI) specifically with the topic related to the analysis of the efficiency of selected 3-phase topologies. The efficiency performance of any power semiconductor system is currently main qualitative indicator due to several reasons. Because each application requires different specification on the circuit complexity, in this paper focus is given on the analysis of possible circuit variations of neutral-point clamped (NPC) converters, i.e. NPC, A-NPC and T-NPC configurations. The circuits design of each topology is reflecting specifications of target application, while in this case the area of power inverter for renewable energy source with nominal power of 10 kW is under consideration. Individual topologies have been evaluated in the way of evaluation of power dissipation within main components of power circuit, i.e. power semiconductor devices, filters and dumping network. At the end of the paper, mutual comparison is provided together with brief evaluation of cons and pros of each topology.
{"title":"Comparisons of operational performance between T-NPC, NPC and A-NPC multillevel converters","authors":"M. Frivaldský, J. Šedo, P. Resutík, B. Hanko","doi":"10.1109/ELEKTRO53996.2022.9803342","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803342","url":null,"abstract":"The article is dealing withi the issue related to the multilevel inverter (MLI) specifically with the topic related to the analysis of the efficiency of selected 3-phase topologies. The efficiency performance of any power semiconductor system is currently main qualitative indicator due to several reasons. Because each application requires different specification on the circuit complexity, in this paper focus is given on the analysis of possible circuit variations of neutral-point clamped (NPC) converters, i.e. NPC, A-NPC and T-NPC configurations. The circuits design of each topology is reflecting specifications of target application, while in this case the area of power inverter for renewable energy source with nominal power of 10 kW is under consideration. Individual topologies have been evaluated in the way of evaluation of power dissipation within main components of power circuit, i.e. power semiconductor devices, filters and dumping network. At the end of the paper, mutual comparison is provided together with brief evaluation of cons and pros of each topology.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131860988","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803719
M. Danko, O. Hock, Robert Plsicík
This paper deals with the design of an automated measuring system for the goniophotometer. The goniophotometer is the device for the measurement of light distribution by changing the position of the luminaire. During measurement, the luminaire spins around the center of the luminaire in two axes, in the defined range. The purpose of the automated measuring system is to control two motors using CAN bus. To change the position of the luminaire, every motor has its own axis of motion around which it rotates. When the luminaire reaches a defined position, the proposed system measures the luminance intensity using a lux meter. Values of the luminance intensity are saved in the file in EULUMDAT format. The proposed system was created in the graphical programing language LabVIEW.
{"title":"Design of automated measuring system for goniophotometer","authors":"M. Danko, O. Hock, Robert Plsicík","doi":"10.1109/ELEKTRO53996.2022.9803719","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803719","url":null,"abstract":"This paper deals with the design of an automated measuring system for the goniophotometer. The goniophotometer is the device for the measurement of light distribution by changing the position of the luminaire. During measurement, the luminaire spins around the center of the luminaire in two axes, in the defined range. The purpose of the automated measuring system is to control two motors using CAN bus. To change the position of the luminaire, every motor has its own axis of motion around which it rotates. When the luminaire reaches a defined position, the proposed system measures the luminance intensity using a lux meter. Values of the luminance intensity are saved in the file in EULUMDAT format. The proposed system was created in the graphical programing language LabVIEW.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127434666","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803470
D. Kacik, I. Martincek, N. Tarjányi, M. Goraus, Juraj Maciak, J. Horák
The design and method of preparing the optical fiber sensor are presented. The optical fiber sensor is based on a Fabry-Pérot interferometer. An optical cavity of the interferometer is formed by single-mode optical fiber. The sensor, connected to the measuring unit, is placed on the foot of the track between sleepers. The functionality of the sensor was verified by passing a trainset consisting of a diesel locomotive and four wagons. From the received signal it is possible to determine the presence of the train at a given time, the number of axles, the speed of the train and to estimate the load of individual axles. Due to the simple installation and multifunctionality of the proposed sensor, the sensor appears to be a good candidate for monitoring railway traffic.
{"title":"Optical Fiber Fabry-Pérot Interferometer and its Application to Railway Transport","authors":"D. Kacik, I. Martincek, N. Tarjányi, M. Goraus, Juraj Maciak, J. Horák","doi":"10.1109/ELEKTRO53996.2022.9803470","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803470","url":null,"abstract":"The design and method of preparing the optical fiber sensor are presented. The optical fiber sensor is based on a Fabry-Pérot interferometer. An optical cavity of the interferometer is formed by single-mode optical fiber. The sensor, connected to the measuring unit, is placed on the foot of the track between sleepers. The functionality of the sensor was verified by passing a trainset consisting of a diesel locomotive and four wagons. From the received signal it is possible to determine the presence of the train at a given time, the number of axles, the speed of the train and to estimate the load of individual axles. Due to the simple installation and multifunctionality of the proposed sensor, the sensor appears to be a good candidate for monitoring railway traffic.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125759138","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803361
I. Jančigová, Michal Mulík, I. Cimrák
The ability of circulating tumor cells and their clusters to cause cancer metastases is not fully understood. Among the factors that influence the metastatic potential is the interaction of cells with vessel walls. In this work we consider two cluster models with variable stiffness in a simple microfluidic bifurcation and examine the contact area over time. We find that softer clusters have larger contact area in both models, but the model in which the clusters can also change their shapes in flow or break apart has lower contact than geometry preserving model of the same stiffness. We also consider the impact of cluster orientation in flow prior to reaching the bifurcation point and conclude that it has a significant impact on the cluster-wall contact area.
{"title":"Contact area of cell cluster in a simple bifurcation","authors":"I. Jančigová, Michal Mulík, I. Cimrák","doi":"10.1109/ELEKTRO53996.2022.9803361","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803361","url":null,"abstract":"The ability of circulating tumor cells and their clusters to cause cancer metastases is not fully understood. Among the factors that influence the metastatic potential is the interaction of cells with vessel walls. In this work we consider two cluster models with variable stiffness in a simple microfluidic bifurcation and examine the contact area over time. We find that softer clusters have larger contact area in both models, but the model in which the clusters can also change their shapes in flow or break apart has lower contact than geometry preserving model of the same stiffness. We also consider the impact of cluster orientation in flow prior to reaching the bifurcation point and conclude that it has a significant impact on the cluster-wall contact area.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129415935","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803687
M. Kučera, M. Gutten, Martin Karman, D. Korenčiak
This paper is focused on the description of the measurement and diagnostics analysis of two dry distribution transformers 22 / 0.4 kV, 0.8 MVA with epoxy resin winding insulation using acoustic emission analysis. It is one of the basic diagnostic and monitoring functions for remote measurement and acoustic measurement using acoustic camera. The dry distribution transformers generate acoustic emissions, thanks to which we can analyze the operating and fault condition of the device. The article presents the use of an acoustic camera for operational monitoring and diagnostics through noise from the winding source and the ferromagnetic core of the transformer. The spatial distribution of the acoustic field as well as its spectra were analyzed. Preliminary results have shown that acoustic analysis can be a useful alternative for analyzing the design state of a power transformer.
{"title":"Analysis of the condition of dry transformers by acoustic emission measurement","authors":"M. Kučera, M. Gutten, Martin Karman, D. Korenčiak","doi":"10.1109/ELEKTRO53996.2022.9803687","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803687","url":null,"abstract":"This paper is focused on the description of the measurement and diagnostics analysis of two dry distribution transformers 22 / 0.4 kV, 0.8 MVA with epoxy resin winding insulation using acoustic emission analysis. It is one of the basic diagnostic and monitoring functions for remote measurement and acoustic measurement using acoustic camera. The dry distribution transformers generate acoustic emissions, thanks to which we can analyze the operating and fault condition of the device. The article presents the use of an acoustic camera for operational monitoring and diagnostics through noise from the winding source and the ferromagnetic core of the transformer. The spatial distribution of the acoustic field as well as its spectra were analyzed. Preliminary results have shown that acoustic analysis can be a useful alternative for analyzing the design state of a power transformer.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130666177","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 : 2022-05-23DOI: 10.1109/elektro53996.2022.9803662
P. Rogałski, M. Zenker, M. Šebok
The article presents a comparison of the currently used solutions in the field of insulating oils with the new Nynas NYTRO BIO 300X bio-carbon oil. The paper shows the results of measurements of an electrotechnical pressboard sample impregnated with bio-carbon oil, the moisture content of which was 4% by weight. Measurements made using the FDS method in the frequency range from 10 mHz to 5 kHz at the temperatures of 293.15 K, 301.15 K, 309.15 K, 317.15 K, 325.15 K and 333.15 K, made it possible to determine the frequency-temperature dependences of the following electrical parameters: admittance, phase shift angle, loss tangent, conductivity and permittivity.
{"title":"The AC measurmets of the composite of cellulose - bio-based hydrocarbon transformer oil – water nanodrops","authors":"P. Rogałski, M. Zenker, M. Šebok","doi":"10.1109/elektro53996.2022.9803662","DOIUrl":"https://doi.org/10.1109/elektro53996.2022.9803662","url":null,"abstract":"The article presents a comparison of the currently used solutions in the field of insulating oils with the new Nynas NYTRO BIO 300X bio-carbon oil. The paper shows the results of measurements of an electrotechnical pressboard sample impregnated with bio-carbon oil, the moisture content of which was 4% by weight. Measurements made using the FDS method in the frequency range from 10 mHz to 5 kHz at the temperatures of 293.15 K, 301.15 K, 309.15 K, 317.15 K, 325.15 K and 333.15 K, made it possible to determine the frequency-temperature dependences of the following electrical parameters: admittance, phase shift angle, loss tangent, conductivity and permittivity.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125885659","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803484
Grzegorz Putynkowski, K. Wożny, E. Szychta, L. Szychta
The spreading application of robotised systems and the technological development of converter systems that cause a number of disturbances of electric power quality give rise to the question whether their impact on the lifetime of electric receivers and their peripheries is not in excess of normative standards. The authors, in cooperation with some authorised after-sales service providers for industrial robot suppliers, have observed a rising number of after-sales complaints that remain unsolved, where the cause of robot stoppage or damage is not diagnosed. The authors believe this situation is directly caused by the fact supply voltage sags and returns to its default value are not registered (a lack of sag records) and relations are not analysed between voltage sags, current, and anomalous states of industrial robots’ automatic systems. In search for evidence of the destructive effects of voltage sags, the authors have undertaken some research and identified states destructive to electric receivers (in this case, industrial robots) in the region the ITIC / SEMI F47 curve defines as no-damage.
{"title":"Destructive states in the area defined as a no-damage region in the ITIC / SEMI F47 curve","authors":"Grzegorz Putynkowski, K. Wożny, E. Szychta, L. Szychta","doi":"10.1109/ELEKTRO53996.2022.9803484","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803484","url":null,"abstract":"The spreading application of robotised systems and the technological development of converter systems that cause a number of disturbances of electric power quality give rise to the question whether their impact on the lifetime of electric receivers and their peripheries is not in excess of normative standards. The authors, in cooperation with some authorised after-sales service providers for industrial robot suppliers, have observed a rising number of after-sales complaints that remain unsolved, where the cause of robot stoppage or damage is not diagnosed. The authors believe this situation is directly caused by the fact supply voltage sags and returns to its default value are not registered (a lack of sag records) and relations are not analysed between voltage sags, current, and anomalous states of industrial robots’ automatic systems. In search for evidence of the destructive effects of voltage sags, the authors have undertaken some research and identified states destructive to electric receivers (in this case, industrial robots) in the region the ITIC / SEMI F47 curve defines as no-damage.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129143462","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803739
M. Janek
In the paper, the setup for measuring the diffraction of light on an optical element in a specific case on a diffraction grating in the remote way is presented. The wavelength of the laser light is known from datasheet. Setup is based on Raspberry Pi 3 Model B, two cameras and two stepper motors, Arduino Nano microcontroller, laser module and lampshade. The mechanical parts were printed on a 3D printer. Base software is programmed in a node-red environment, the Arduino IDE environment is used to control stepper motors. Physical data processing is based on reading the position of light spots on graph paper. The collected distribution of the light spot on lampshade and the known wavelength of laser light is used to determine the lattice constant of the optical element. Other measurement options such as measurement on an optical prism and on calcite crystal are also shortly discussed. Possible hardware and software implementation issues are also discussed.
{"title":"Diffraction measurement - remote experiment","authors":"M. Janek","doi":"10.1109/ELEKTRO53996.2022.9803739","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803739","url":null,"abstract":"In the paper, the setup for measuring the diffraction of light on an optical element in a specific case on a diffraction grating in the remote way is presented. The wavelength of the laser light is known from datasheet. Setup is based on Raspberry Pi 3 Model B, two cameras and two stepper motors, Arduino Nano microcontroller, laser module and lampshade. The mechanical parts were printed on a 3D printer. Base software is programmed in a node-red environment, the Arduino IDE environment is used to control stepper motors. Physical data processing is based on reading the position of light spots on graph paper. The collected distribution of the light spot on lampshade and the known wavelength of laser light is used to determine the lattice constant of the optical element. Other measurement options such as measurement on an optical prism and on calcite crystal are also shortly discussed. Possible hardware and software implementation issues are also discussed.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132747119","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 : 2022-05-23DOI: 10.1109/ELEKTRO53996.2022.9803706
M. Vagaš, A. Galajdová
the coming digitization, knowledge, and response to the current operating state of the automated workplace, as well as the need to visualize the required information using a suitable system component, is the current trend of optical and acoustic visualization. Therefore, the article aims to present a reliable visualization of the monitored automated workplace, representing a fundamental change in physical variables and states. This article explains the configuration, integration, and verification of a LED SmartLight device based on IO-Link communication. The article also includes a description of the individual control blocks and instructions necessary for implementing such a signaling device. The simulation of the automated process (TIA Portal environment) preceded the experimental deployment in the existing robotic assembly cell of FESTO (FMS 500). The results indicate immediate and clear signaling, exceeding the limit values of the operating state or the ability to read the tendency and course of the selected physical quantity.
{"title":"Integration of LED SmartLight device into the automated process","authors":"M. Vagaš, A. Galajdová","doi":"10.1109/ELEKTRO53996.2022.9803706","DOIUrl":"https://doi.org/10.1109/ELEKTRO53996.2022.9803706","url":null,"abstract":"the coming digitization, knowledge, and response to the current operating state of the automated workplace, as well as the need to visualize the required information using a suitable system component, is the current trend of optical and acoustic visualization. Therefore, the article aims to present a reliable visualization of the monitored automated workplace, representing a fundamental change in physical variables and states. This article explains the configuration, integration, and verification of a LED SmartLight device based on IO-Link communication. The article also includes a description of the individual control blocks and instructions necessary for implementing such a signaling device. The simulation of the automated process (TIA Portal environment) preceded the experimental deployment in the existing robotic assembly cell of FESTO (FMS 500). The results indicate immediate and clear signaling, exceeding the limit values of the operating state or the ability to read the tendency and course of the selected physical quantity.","PeriodicalId":396752,"journal":{"name":"2022 ELEKTRO (ELEKTRO)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131744698","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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