Pub Date : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0030
Moon Moon Bordeori, N. Gupta
Electrical treeing is one of the most common pre-breakdown degradation mechanisms in polymeric insulating materials. Addition of appropriate quantities of nanoparticles to bulk polymers has been reported to hinder tree progression. A clear understanding of the electrical tree growth mechanism in nanodielectrics would help in their deployment as reliable insulating materials for high voltage apparatus. In the current work, a numerical model based on the Weismann-Zeller model is adapted for application to nanocomposites. The model is used to computationally study the effect of the inclusion of nanoparticles, including the effect of their size and material permittivity.
{"title":"Study of Electrical Tree Progression in a Dielectric with Addition of Nanofillers","authors":"Moon Moon Bordeori, N. Gupta","doi":"10.1109/CATCON47128.2019.CN0030","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0030","url":null,"abstract":"Electrical treeing is one of the most common pre-breakdown degradation mechanisms in polymeric insulating materials. Addition of appropriate quantities of nanoparticles to bulk polymers has been reported to hinder tree progression. A clear understanding of the electrical tree growth mechanism in nanodielectrics would help in their deployment as reliable insulating materials for high voltage apparatus. In the current work, a numerical model based on the Weismann-Zeller model is adapted for application to nanocomposites. The model is used to computationally study the effect of the inclusion of nanoparticles, including the effect of their size and material permittivity.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"140 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122441169","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0111
Sorokhaibam Nilakanta Meitei, K. Borah, S. Chatterjee
This paper presents an analysis of acoustic pressure wave distribution in a power transformer due to partial discharge (PD) using the finite-element-method (FEM) based software COMSOL Multiphysics. The acoustic PD is simulated at four different locations of the transformer in the core, in the low voltage (LV) winding, in the high voltage (HV) winding and in the oil duct, respectively. The acoustic pressure wave generated by the PD is investigated in the transient state. Results suggest that the acoustic pressure wave propagation inside the transformer depends on the PD induced location. Moreover, a more significant acoustic pressure gradient is perceived in the region with a higher speed of sound.
{"title":"Finite Element Method Based Modelling and Analysis of Partial Discharge Acoustic Wave Propagation in an Oil-Filled Power Transformer","authors":"Sorokhaibam Nilakanta Meitei, K. Borah, S. Chatterjee","doi":"10.1109/CATCON47128.2019.CN0111","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0111","url":null,"abstract":"This paper presents an analysis of acoustic pressure wave distribution in a power transformer due to partial discharge (PD) using the finite-element-method (FEM) based software COMSOL Multiphysics. The acoustic PD is simulated at four different locations of the transformer in the core, in the low voltage (LV) winding, in the high voltage (HV) winding and in the oil duct, respectively. The acoustic pressure wave generated by the PD is investigated in the transient state. Results suggest that the acoustic pressure wave propagation inside the transformer depends on the PD induced location. Moreover, a more significant acoustic pressure gradient is perceived in the region with a higher speed of sound.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131112373","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.76
R. Ghosh, P. Seri, G. Montanari
With increased voltage and faster switch rise time, the major issues faced while designing insulation systems for inverter-fed rotating machines is how to measure PD correctly and evaluate PDIV-RPDIV in type and qualification tests for Type I insulation. The current PD measurement techniques as per IEC 60034-27-5 involve the use of high pass filters to suppress the switching disturbance and retain the PD. This approach, however, may be not effective for fast risetime and high-amplitude voltages, where the disturbance spectrum spreads out in the higher frequency range and can overlap with the PD spectrum, rendering any frequency domain approach poorly effective. Therefore, new techniques for separation of PD from voltage switching disturbance must be investigated. This paper presents a time-domain approach for PD measurement under fast impulses and high voltage values. Results show that this approach has several advantages over the conventional one, and it can be used alone or in combination with filtering techniques.
{"title":"Measuring Partial Discharges under Power Electronics Waveforms: from Slow to Ultra-fast Voltage Impulse Risetime","authors":"R. Ghosh, P. Seri, G. Montanari","doi":"10.1109/CATCON47128.2019.76","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.76","url":null,"abstract":"With increased voltage and faster switch rise time, the major issues faced while designing insulation systems for inverter-fed rotating machines is how to measure PD correctly and evaluate PDIV-RPDIV in type and qualification tests for Type I insulation. The current PD measurement techniques as per IEC 60034-27-5 involve the use of high pass filters to suppress the switching disturbance and retain the PD. This approach, however, may be not effective for fast risetime and high-amplitude voltages, where the disturbance spectrum spreads out in the higher frequency range and can overlap with the PD spectrum, rendering any frequency domain approach poorly effective. Therefore, new techniques for separation of PD from voltage switching disturbance must be investigated. This paper presents a time-domain approach for PD measurement under fast impulses and high voltage values. Results show that this approach has several advantages over the conventional one, and it can be used alone or in combination with filtering techniques.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133672963","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0057
P. Singh, S. Dutta, A. Baral, S. Chakravorti
Power system networks mainly use porcelain disc insulators for insulating live conductor from supporting structure. Insulators, used in power system network are generally employed for open-environment applications. Outdoor porcelain insulator discs get easily contaminated due to different types of pollutants such as salt, kaolin, heavy rain, fog, humidity. Further, these pollutants provide path for leakage current to flow along the surface of the insulator. This leakage current magnitude increases with increase in contamination and humidity. Therefore, identification of contamination level for porcelain insulator disc is necessary for uninterrupted and smooth power system operation. Hence, in the present work, a methodology is proposed to estimate the levels of contaminations using leakage current measured from an 11kV porcelain disc insulator (simulating different contamination levels). Detrended fluctuation analysis (DFA) has been applied on the measured leakage current profiles to provide meaningful information about contamination deposited on insulator surface.
{"title":"Contamination Level Assessment in Porcelain Disc Insulator using Detrended Fluctuation Analysis","authors":"P. Singh, S. Dutta, A. Baral, S. Chakravorti","doi":"10.1109/CATCON47128.2019.CN0057","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0057","url":null,"abstract":"Power system networks mainly use porcelain disc insulators for insulating live conductor from supporting structure. Insulators, used in power system network are generally employed for open-environment applications. Outdoor porcelain insulator discs get easily contaminated due to different types of pollutants such as salt, kaolin, heavy rain, fog, humidity. Further, these pollutants provide path for leakage current to flow along the surface of the insulator. This leakage current magnitude increases with increase in contamination and humidity. Therefore, identification of contamination level for porcelain insulator disc is necessary for uninterrupted and smooth power system operation. Hence, in the present work, a methodology is proposed to estimate the levels of contaminations using leakage current measured from an 11kV porcelain disc insulator (simulating different contamination levels). Detrended fluctuation analysis (DFA) has been applied on the measured leakage current profiles to provide meaningful information about contamination deposited on insulator surface.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"233 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132246854","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0047
A. S. Kumar, K. Elanseralathan
One of the major challenges in power transmission is the losses incurred during transmitting power from the isolated power generation source to substation. Transmission through High Voltage Direct Current (HVDC) is an economically reliable alternative and a promising solution to minimize losses over long distance transmission. The aim of our work is to replace the conventionally used cross linked poly ethylene (thermo set material) by an alternative thermoplastic material in order to increase the life of the cable. Thermoplastic materials are highly desirable for HVDC cable insulation because of its recyclability and absence of bye products. In this work the dielectric properties of the isotactic polypropylene (iPP) is improved by introduction of inorganic nanoparticles. Investigation is done on the break down strength of the iPP/nano composites thin film with different weight percentage for HVAC and HVDC applications. A comprehensive analysis of iPP/nano composites its suitability in HVDC cable insulation application.
{"title":"Assessment of Recyclable thermoplastic material for HVDC cable application","authors":"A. S. Kumar, K. Elanseralathan","doi":"10.1109/CATCON47128.2019.CN0047","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0047","url":null,"abstract":"One of the major challenges in power transmission is the losses incurred during transmitting power from the isolated power generation source to substation. Transmission through High Voltage Direct Current (HVDC) is an economically reliable alternative and a promising solution to minimize losses over long distance transmission. The aim of our work is to replace the conventionally used cross linked poly ethylene (thermo set material) by an alternative thermoplastic material in order to increase the life of the cable. Thermoplastic materials are highly desirable for HVDC cable insulation because of its recyclability and absence of bye products. In this work the dielectric properties of the isotactic polypropylene (iPP) is improved by introduction of inorganic nanoparticles. Investigation is done on the break down strength of the iPP/nano composites thin film with different weight percentage for HVAC and HVDC applications. A comprehensive analysis of iPP/nano composites its suitability in HVDC cable insulation application.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"169 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134320268","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0092
P. R. Sai Siddu, S. Ravi Chandran, S. Usa
Due to the upgradation of power systems, the power rating of power transformers increases which requires more efficiency and good winding mechanical strength. This has been made possible with the use of Continuously Transposed Conductor (CTC) windings in power transformer design. CTC winding reduces eddy losses and provides uniform temperature distribution throughout the winding and high mechanical withstand capability in short circuit conditions. In this work, CTC and the equivalent DISC windings of equally rated power transformers of the same manufacturer are considered for the analysis. The eddy current loss and winding deformation under short circuit force of both the windings are computed using finite element based field solvers and compared.
{"title":"Eddy Current and Magneto-Structural Analysis on Transformer Winding with Continuously Transposed Conductors","authors":"P. R. Sai Siddu, S. Ravi Chandran, S. Usa","doi":"10.1109/CATCON47128.2019.CN0092","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0092","url":null,"abstract":"Due to the upgradation of power systems, the power rating of power transformers increases which requires more efficiency and good winding mechanical strength. This has been made possible with the use of Continuously Transposed Conductor (CTC) windings in power transformer design. CTC winding reduces eddy losses and provides uniform temperature distribution throughout the winding and high mechanical withstand capability in short circuit conditions. In this work, CTC and the equivalent DISC windings of equally rated power transformers of the same manufacturer are considered for the analysis. The eddy current loss and winding deformation under short circuit force of both the windings are computed using finite element based field solvers and compared.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114360741","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.42
P. Seri, R. Ghosh, H. Naderiallaf, G. Montanari
New nanostructured insulating materials are investigated, within the European project GRIDABLE, to be used for DC cable and capacitors. Besides electrical, thermal and mechanical properties, and life behavior, work is being done to evaluate their capability to endure highly stressing conditions as those cause by the inception of partial discharges, PD. This paper, in particular, analyzes what happens during energization of a DC cable or capacitors, when voltage goes from zero to the nominal value in a few seconds, while the internal electrical field takes longer time to reach the DC steady state configuration. During an energization transient, indeed, electrical field in insulation, and insulation defects (as cavities), is driven by permittivity, not conductivity as in steady state. Hence, PD might occur with high repetition rate, which would not occur, or at much lower repetition rate, in steady state. The way to evaluate the time constant of the transient, that is, through charging current measurement, is described and successfully fitted to the results of PD measurements performed on two types of polypropylene, PP: neat and nanostructured, and a crosslinked polyethylene, XLPE, having significantly different electrical characteristics.
{"title":"Investigating Energization Transients and the Potentiality of Partial Discharge Inception and Damage in Nanofilled Polypropylene Insulation for DC Cables and Capacitors","authors":"P. Seri, R. Ghosh, H. Naderiallaf, G. Montanari","doi":"10.1109/CATCON47128.2019.42","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.42","url":null,"abstract":"New nanostructured insulating materials are investigated, within the European project GRIDABLE, to be used for DC cable and capacitors. Besides electrical, thermal and mechanical properties, and life behavior, work is being done to evaluate their capability to endure highly stressing conditions as those cause by the inception of partial discharges, PD. This paper, in particular, analyzes what happens during energization of a DC cable or capacitors, when voltage goes from zero to the nominal value in a few seconds, while the internal electrical field takes longer time to reach the DC steady state configuration. During an energization transient, indeed, electrical field in insulation, and insulation defects (as cavities), is driven by permittivity, not conductivity as in steady state. Hence, PD might occur with high repetition rate, which would not occur, or at much lower repetition rate, in steady state. The way to evaluate the time constant of the transient, that is, through charging current measurement, is described and successfully fitted to the results of PD measurements performed on two types of polypropylene, PP: neat and nanostructured, and a crosslinked polyethylene, XLPE, having significantly different electrical characteristics.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125593317","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0036
Asha Sharma, S. Basu, N. Gupta
The improvement of dielectric properties of a polymer through addition of nanofillers is considered to be primarily due to the interface formed around the nanoparticle embedded in polymeric matrix. Researchers have attempted indirect methods to detect the interfacial region and suggested that an interfacial region of finite thickness and permittivity different from filler and bulk matrix exists. An electrical double layer of charge around each nanoparticle is also hypothesized. In the current computational study, a Finite Element Method (FEM) based model is used to simulate the experimental set-up for Electrostatic Force Microscopy (EFM) and to generate computationally the EFM phase images. The efficacy of this model in detecting charge around a nanoparticle is studied.
{"title":"Detection of Charge around a Nanoparticle in a Nanodielectric","authors":"Asha Sharma, S. Basu, N. Gupta","doi":"10.1109/CATCON47128.2019.CN0036","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0036","url":null,"abstract":"The improvement of dielectric properties of a polymer through addition of nanofillers is considered to be primarily due to the interface formed around the nanoparticle embedded in polymeric matrix. Researchers have attempted indirect methods to detect the interfacial region and suggested that an interfacial region of finite thickness and permittivity different from filler and bulk matrix exists. An electrical double layer of charge around each nanoparticle is also hypothesized. In the current computational study, a Finite Element Method (FEM) based model is used to simulate the experimental set-up for Electrostatic Force Microscopy (EFM) and to generate computationally the EFM phase images. The efficacy of this model in detecting charge around a nanoparticle is studied.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125769468","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0050
E. Skariah, S. T K
Strict emission regulations are being implemented worldwide to tackle the issues of air pollution these years. It is important that suitable technological solutions have to be introduced in addition to the conventional pollution control methods. Non thermal plasma reactors were proved to be effective in tackling several pollutants, if properly tuned. One dimensional numerical model and mathematical model of a dielectric barrier discharge reactor is simulated in this work. The solutions of these models are coupled to obtain the best operating conditions of the reactor under specific emission conditions of oxides of nitrogen. The importance of power deposited and decomposition rate constant is analyzed. It is inferred that careful tuning of operating parameters can improve the efficiency of DBD reactor.
{"title":"Prediction of Feasible Operating Point for a DBD Reactor Based on Decomposition Rate Constant","authors":"E. Skariah, S. T K","doi":"10.1109/CATCON47128.2019.CN0050","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0050","url":null,"abstract":"Strict emission regulations are being implemented worldwide to tackle the issues of air pollution these years. It is important that suitable technological solutions have to be introduced in addition to the conventional pollution control methods. Non thermal plasma reactors were proved to be effective in tackling several pollutants, if properly tuned. One dimensional numerical model and mathematical model of a dielectric barrier discharge reactor is simulated in this work. The solutions of these models are coupled to obtain the best operating conditions of the reactor under specific emission conditions of oxides of nitrogen. The importance of power deposited and decomposition rate constant is analyzed. It is inferred that careful tuning of operating parameters can improve the efficiency of DBD reactor.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131305190","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 : 2019-11-01DOI: 10.1109/CATCON47128.2019.CN0112
D. Verginadis, M. Danikas, R. Sarathi
This paper deals with surface discharges and flashover voltages on epoxy resin nanocomposite surfaces. Factors, such as, water droplet number and volume, droplet conductivity as well as the distance of the droplets from the electrodes affect both surface discharges and flashover voltages. Moreover, the degradation of the insulting material is indicated in this paper.
{"title":"Epoxy resin with montmorillonite nanofillers: Flashover voltages and surface discharges","authors":"D. Verginadis, M. Danikas, R. Sarathi","doi":"10.1109/CATCON47128.2019.CN0112","DOIUrl":"https://doi.org/10.1109/CATCON47128.2019.CN0112","url":null,"abstract":"This paper deals with surface discharges and flashover voltages on epoxy resin nanocomposite surfaces. Factors, such as, water droplet number and volume, droplet conductivity as well as the distance of the droplets from the electrodes affect both surface discharges and flashover voltages. Moreover, the degradation of the insulting material is indicated in this paper.","PeriodicalId":183797,"journal":{"name":"2019 IEEE 4th International Conference on Condition Assessment Techniques in Electrical Systems (CATCON)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127203349","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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