Pub Date : 2018-05-01DOI: 10.1109/ICHQP.2018.8378817
M. Limas, Daniel Agudelo-Martinez, Jan Bacca Rodríguez, A. Pavas
In this paper, an analysis of the emissions of an LED lamp is performed, when it is connected in parallel with electrical devices of linear and non-linear behavior. The objective is to determine if the presence of other loads connected in the same installation can cause a change in the emissions of the LED lamp. A measurement assembly and a test electrical network are built to perform the measurements of voltage and current emissions generated by the LED lamp between 1 Hz and 250 kHz. Incandescent, CFL and LED lamps of different power and technology are used as test loads. The analysis of results indicates that the increase of devices connected in parallel to an LED bulb can in general reduce the current THD. However, there are components in the current emission that increase their RMS value.
{"title":"Conducted emission variations using low power LED lamps connected to other devices","authors":"M. Limas, Daniel Agudelo-Martinez, Jan Bacca Rodríguez, A. Pavas","doi":"10.1109/ICHQP.2018.8378817","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378817","url":null,"abstract":"In this paper, an analysis of the emissions of an LED lamp is performed, when it is connected in parallel with electrical devices of linear and non-linear behavior. The objective is to determine if the presence of other loads connected in the same installation can cause a change in the emissions of the LED lamp. A measurement assembly and a test electrical network are built to perform the measurements of voltage and current emissions generated by the LED lamp between 1 Hz and 250 kHz. Incandescent, CFL and LED lamps of different power and technology are used as test loads. The analysis of results indicates that the increase of devices connected in parallel to an LED bulb can in general reduce the current THD. However, there are components in the current emission that increase their RMS value.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"53 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89058140","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378838
E. Cazacu, Maria-Cǎtǎlina Petrescu, V. Ioniță, L. Petrescu
Most of the in-service power distribution transformers from the industrial electric facilities were designed to operate under pure sinusoidal state conditions. Nevertheless, the majority of the loads from modern electric installations are intrinsically nonlinear and consequently, they generate nonsinusoidal currents. These high-order harmonics (present into the current waveform spectrum) have a negative impact on the transformers thermal and electrical operating parameters and, ultimately, limit the machine loading capability. The paper quantitatively investigates the transformer behavior under distorted current conditions by developing a procedure for evaluating different relevant operating quantities (maximum permissible current, the hottest spot temperature, aging acceleration factor and the machine remaining lifetime). The computation relays on the international standard recommendation and mainly uses the load current harmonic spectrum and the transformer rated data. To reveal the proposed procedure performance, a distribution transformer of 400 kVA from an industrial plasterboard facility is investigated.
{"title":"Nonsinusoidal load current effect on the electrical and thermal operating parameters of oil filled power distribution transformers","authors":"E. Cazacu, Maria-Cǎtǎlina Petrescu, V. Ioniță, L. Petrescu","doi":"10.1109/ICHQP.2018.8378838","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378838","url":null,"abstract":"Most of the in-service power distribution transformers from the industrial electric facilities were designed to operate under pure sinusoidal state conditions. Nevertheless, the majority of the loads from modern electric installations are intrinsically nonlinear and consequently, they generate nonsinusoidal currents. These high-order harmonics (present into the current waveform spectrum) have a negative impact on the transformers thermal and electrical operating parameters and, ultimately, limit the machine loading capability. The paper quantitatively investigates the transformer behavior under distorted current conditions by developing a procedure for evaluating different relevant operating quantities (maximum permissible current, the hottest spot temperature, aging acceleration factor and the machine remaining lifetime). The computation relays on the international standard recommendation and mainly uses the load current harmonic spectrum and the transformer rated data. To reveal the proposed procedure performance, a distribution transformer of 400 kVA from an industrial plasterboard facility is investigated.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"86 2 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90970602","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378924
Triin Kangro, J. Kilter, J. De Silva
This paper discusses high voltage ac underground cable sheath layer modelling for network studies in EMT type program. In EMT studies, the cable compound sheath layer is considered as a single solid layer, therefore the simplified sheath layer representation is needed. This paper presents developed approaches for cable sheath modelling. The approximations made in sheath parameters can lead to inaccuracies in study results. Therefore to determinate the sheath modelling accuracy, network power flow, short-circuit and lightning surge studies are analyzed. The network bus voltages are observed and compared at various sheath modelling approaches. Network power flow study shows no major variation in results when different modelling approaches are used. However, the short- circuit and lightning surge study results show that chosen cable sheath modelling approach has significant effect to the network bus voltage values. The needed extent of network modelling area is also analyzed in this paper. At cable networks, the considered modelling area needs to be wider than for OHL networks. The extent of modelling area should be decided corresponding to the total length of cable lines. Cable sheath modelling approach recommendations for network studies are provided in this paper.
{"title":"Comparative analysis of HVAC cable metallic sheath modelling approaches for network studies","authors":"Triin Kangro, J. Kilter, J. De Silva","doi":"10.1109/ICHQP.2018.8378924","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378924","url":null,"abstract":"This paper discusses high voltage ac underground cable sheath layer modelling for network studies in EMT type program. In EMT studies, the cable compound sheath layer is considered as a single solid layer, therefore the simplified sheath layer representation is needed. This paper presents developed approaches for cable sheath modelling. The approximations made in sheath parameters can lead to inaccuracies in study results. Therefore to determinate the sheath modelling accuracy, network power flow, short-circuit and lightning surge studies are analyzed. The network bus voltages are observed and compared at various sheath modelling approaches. Network power flow study shows no major variation in results when different modelling approaches are used. However, the short- circuit and lightning surge study results show that chosen cable sheath modelling approach has significant effect to the network bus voltage values. The needed extent of network modelling area is also analyzed in this paper. At cable networks, the considered modelling area needs to be wider than for OHL networks. The extent of modelling area should be decided corresponding to the total length of cable lines. Cable sheath modelling approach recommendations for network studies are provided in this paper.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"25 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84105630","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378842
H. Shadmehr, R. C. Gandolfi
The increasing use of grid connected power electronic systems generates a set of interference phenomena between those devices and distribution grids. Power electronic systems are both sensitive to voltage disturbances and sources of disturbances, such as current harmonic distortion, voltages unbalance and flicker. Such phenomena motivated the study of a system named Open Unified Power Quality Conditioner, based on power electronic converters, used for the improvement of the Power Quality level in low voltage distribution grids. The study, mainly theoretical, has addressed the issue of compensators coordination under different operating conditions.
{"title":"Logical coordination between LV compensation devices to provide different PQ levels in the distribution network","authors":"H. Shadmehr, R. C. Gandolfi","doi":"10.1109/ICHQP.2018.8378842","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378842","url":null,"abstract":"The increasing use of grid connected power electronic systems generates a set of interference phenomena between those devices and distribution grids. Power electronic systems are both sensitive to voltage disturbances and sources of disturbances, such as current harmonic distortion, voltages unbalance and flicker. Such phenomena motivated the study of a system named Open Unified Power Quality Conditioner, based on power electronic converters, used for the improvement of the Power Quality level in low voltage distribution grids. The study, mainly theoretical, has addressed the issue of compensators coordination under different operating conditions.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"50 5 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81672387","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378894
Anusuya Arunan, J. Ravishankar, E. Ambikairajah
The rate of change of frequency following any disturbance in LV islanded microgrids is not only relatively high compared to conventional system, but also becomes location specific, due to their high R/X ratio lines. This makes the disturbance detection challenging. Conventional power imbalance calculation methods are not applicable due to variation of inertia with time. This paper proposes a novel real-time disturbance detection technique, independent to the system inertia. Three different Support Vector Machine regression models are created with three different feature selections. Results show that, some local parameters such as voltages at different locations should also be included with the frequency features for the accurate disturbance detection. This method can detect the amount of load disturbance within 0.5 second following the disturbance. The proposed algorithm is tested with an unseen test data. A multi-source islanded microgrid is used to collect the data, which is modelled in MATLAB/SIMULINK.
{"title":"Real-time disturbance detection in LV islanded microgrid","authors":"Anusuya Arunan, J. Ravishankar, E. Ambikairajah","doi":"10.1109/ICHQP.2018.8378894","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378894","url":null,"abstract":"The rate of change of frequency following any disturbance in LV islanded microgrids is not only relatively high compared to conventional system, but also becomes location specific, due to their high R/X ratio lines. This makes the disturbance detection challenging. Conventional power imbalance calculation methods are not applicable due to variation of inertia with time. This paper proposes a novel real-time disturbance detection technique, independent to the system inertia. Three different Support Vector Machine regression models are created with three different feature selections. Results show that, some local parameters such as voltages at different locations should also be included with the frequency features for the accurate disturbance detection. This method can detect the amount of load disturbance within 0.5 second following the disturbance. The proposed algorithm is tested with an unseen test data. A multi-source islanded microgrid is used to collect the data, which is modelled in MATLAB/SIMULINK.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"1 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82144074","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378873
M. Markovska, D. Taskovski
Power quality (PQ) disturbances classification plays an essential role in ensuring high quality power supply of the power grid. One of the main issues in classification is how to extract the “right” features from massive amount of PQ data. The feature selection should be performed for the aim of not only increasing the classification accuracy, but in the same time reducing the calculation time of the classification algorithm. Accordingly, in this work we investigate the effectiveness of the wavelet based features on the classification accuracy in order to perform optimal feature extraction method. The investigation is made using three different classifiers, in case of pure PQ signals and PQ signals accompanied with white Gaussian noise. The results show that the effectiveness of a given feature is not general, but it depends on the kind of the other features it is used with and the noise level present in the signal.
{"title":"The effectiveness of wavelet based features on power quality disturbances classification in noisy environment","authors":"M. Markovska, D. Taskovski","doi":"10.1109/ICHQP.2018.8378873","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378873","url":null,"abstract":"Power quality (PQ) disturbances classification plays an essential role in ensuring high quality power supply of the power grid. One of the main issues in classification is how to extract the “right” features from massive amount of PQ data. The feature selection should be performed for the aim of not only increasing the classification accuracy, but in the same time reducing the calculation time of the classification algorithm. Accordingly, in this work we investigate the effectiveness of the wavelet based features on the classification accuracy in order to perform optimal feature extraction method. The investigation is made using three different classifiers, in case of pure PQ signals and PQ signals accompanied with white Gaussian noise. The results show that the effectiveness of a given feature is not general, but it depends on the kind of the other features it is used with and the noise level present in the signal.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"96 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78263111","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378942
T. Ding, Hongkun Chen, Bin Wu, Pan Hu
On the basis of the introduction to the topology of PWM-based electric vehicle (EV) chargers considering control strategy, a theoretical analysis of the harmonic generation mechanism is conducted. By establishing simulation models of the charger, the distribution order of characteristic harmonic generated by single charger is analyzed. Furthermore, the harmonic coupling characteristics of multiple chargers working simultaneously are also discussed. The simulation results show that the harmonics generated by single charger mainly consist of high frequency components, including a small amount of low frequency components. As for multiple chargers, with the increase of the number of the chargers and the charging power, each harmonic current ratio and the current total harmonic distortion both show a downward trend.
{"title":"Harmonic characteristics analysis of PWM-based electric vehicle chargers considering control strategy","authors":"T. Ding, Hongkun Chen, Bin Wu, Pan Hu","doi":"10.1109/ICHQP.2018.8378942","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378942","url":null,"abstract":"On the basis of the introduction to the topology of PWM-based electric vehicle (EV) chargers considering control strategy, a theoretical analysis of the harmonic generation mechanism is conducted. By establishing simulation models of the charger, the distribution order of characteristic harmonic generated by single charger is analyzed. Furthermore, the harmonic coupling characteristics of multiple chargers working simultaneously are also discussed. The simulation results show that the harmonics generated by single charger mainly consist of high frequency components, including a small amount of low frequency components. As for multiple chargers, with the increase of the number of the chargers and the charging power, each harmonic current ratio and the current total harmonic distortion both show a downward trend.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"62 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77592210","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378826
Z. Staroszczyk
In the introductory part of the paper problems with power grid impedance determination and interpretation are discussed. Research instrumentation for getting the Thevenin grid model, with raw impedance descriptor in kHz/MHz frequency band is presented and compared. The essential part of this paper is focused on subgrid impedance parameterization which allows to get its physical, circuit based model. With the use of nonlinear fitting the model parameters are tuned to get the lowest discrepancy between the observed and circuit modeled impedance of the subgrid in selected frequency nodes. The physical based subgrid model delivers useful engineering information on the grid and can be easily integrated with simulation programs capable of running reliable software experiments on the simulated grid.
{"title":"Power grids: Subgrid impedance determination and its structural model parameterization","authors":"Z. Staroszczyk","doi":"10.1109/ICHQP.2018.8378826","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378826","url":null,"abstract":"In the introductory part of the paper problems with power grid impedance determination and interpretation are discussed. Research instrumentation for getting the Thevenin grid model, with raw impedance descriptor in kHz/MHz frequency band is presented and compared. The essential part of this paper is focused on subgrid impedance parameterization which allows to get its physical, circuit based model. With the use of nonlinear fitting the model parameters are tuned to get the lowest discrepancy between the observed and circuit modeled impedance of the subgrid in selected frequency nodes. The physical based subgrid model delivers useful engineering information on the grid and can be easily integrated with simulation programs capable of running reliable software experiments on the simulated grid.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"12 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81404566","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378943
S. Barcellona, S. Negri, G. Superti-Furga
Pulse-width modulation is one of the most common modulation strategies. Nevertheless, some issues about the harmonic content of the output voltage and current are still debated. In the present paper, the space vector and zero component are used for harmonic analysis of the naturally sampled three-phase PWM. An overall analytical formulation of the Fourier series is derived, through which a detailed evaluation of the ripple shifting among the phases is carried out. Simulations support the consistency of the proposed analysis.
{"title":"Space-vector analysis of harmonic distortion in three-phase PWM","authors":"S. Barcellona, S. Negri, G. Superti-Furga","doi":"10.1109/ICHQP.2018.8378943","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378943","url":null,"abstract":"Pulse-width modulation is one of the most common modulation strategies. Nevertheless, some issues about the harmonic content of the output voltage and current are still debated. In the present paper, the space vector and zero component are used for harmonic analysis of the naturally sampled three-phase PWM. An overall analytical formulation of the Fourier series is derived, through which a detailed evaluation of the ripple shifting among the phases is carried out. Simulations support the consistency of the proposed analysis.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"19 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82124913","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 : 2018-05-01DOI: 10.1109/ICHQP.2018.8378899
T. Wohlfahrt, Christian Waniek, J. Myrzik, Jan Meyer, P. Schegner
In this paper, the impact of supraharmonic disturbances on electronic mass-market equipment concerning the equipment's lifetime by the aging of the built-in electrolytic capacitors for voltage smoothing is described. In order to get an overview of the impact of the supraharmonic distortion, the increasing input currents of two typical household devices by applying an additional supraharmonic grid voltage distortion of up to 7 V are shown. Due to this additional stress, the aging of the built-in electrolytic capacitors is accelerated and will be analyzed. Therefore, different parameters of a typically used electrolytic capacitor like the core temperature, the frequency- and temperature-dependent equivalent series resistance and the overall thermal resistance are measured and calculated. Based on these values, a lifetime multiplier is computed for different ambient temperatures, ripple frequencies and ripple current amplitudes to assess the impact of these parameters on the capacitor's and thus the devices' lifetime.
{"title":"Supraharmonic disturbances: Lifetime reduction of electronic mass-market equipment by the aging of electrolytic capacitors","authors":"T. Wohlfahrt, Christian Waniek, J. Myrzik, Jan Meyer, P. Schegner","doi":"10.1109/ICHQP.2018.8378899","DOIUrl":"https://doi.org/10.1109/ICHQP.2018.8378899","url":null,"abstract":"In this paper, the impact of supraharmonic disturbances on electronic mass-market equipment concerning the equipment's lifetime by the aging of the built-in electrolytic capacitors for voltage smoothing is described. In order to get an overview of the impact of the supraharmonic distortion, the increasing input currents of two typical household devices by applying an additional supraharmonic grid voltage distortion of up to 7 V are shown. Due to this additional stress, the aging of the built-in electrolytic capacitors is accelerated and will be analyzed. Therefore, different parameters of a typically used electrolytic capacitor like the core temperature, the frequency- and temperature-dependent equivalent series resistance and the overall thermal resistance are measured and calculated. Based on these values, a lifetime multiplier is computed for different ambient temperatures, ripple frequencies and ripple current amplitudes to assess the impact of these parameters on the capacitor's and thus the devices' lifetime.","PeriodicalId":6506,"journal":{"name":"2018 18th International Conference on Harmonics and Quality of Power (ICHQP)","volume":"30 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2018-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78238891","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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