Pub Date : 2024-01-29DOI: 10.1109/LEMCPA.2024.3359485
Makarand M. Kane;Nathaniel Taylor;Daniel Månsson
Considering the inverter as the source of electromagnetic emission signals in a photovoltaic (PV) plant, a comprehensive set of measurements of conducted emissions at the input and output of the inverter in a 10-kW PV plant are presented. These are particularly relevant on the backdrop of 1) the ban of products in the EU market due to noncompliance and 2) the increased switching frequency in the inverters $(sim 100$ s of kHz) in the near future. Specifically, the common-mode (CM) and differential-mode (DM) currents and voltages are measured, and their frequency-domain behavior is studied. It is suggested that conducted emissions from PV can be classified into three zones: 1) extremely low-frequency (ELF) zone, 2) power frequency zone, and 3) switching frequency zone. Important observations from this exercise are the measurement of harmonic contents of current with total rated current distortion (TRD), imbalance in the output voltage, and low-frequency ripples in the dc voltage. Frequency-domain behavior of the CM quantities is studied which throws light on important points like a relation between input and output CM quantities and a relation between CM voltage and CM current.
考虑到逆变器是光伏（PV）电站中电磁辐射信号的来源，本文介绍了一套对 10 千瓦光伏电站中逆变器输入和输出端传导辐射的综合测量结果。在以下背景下，这些测量结果尤为重要：1）由于不合规产品在欧盟市场被禁售；2）在不久的将来，逆变器的开关频率将提高（100 kHz）。具体而言，测量了共模（CM）和差模（DM）电流和电压，并研究了它们的频域行为。研究表明，光伏发电的传导辐射可分为三个区域：1) 极低频 (ELF) 区；2) 电源频率区；3) 开关频率区。这项工作的重要观测指标包括测量电流谐波含量与总额定电流失真 (TRD)、输出电压不平衡以及直流电压的低频纹波。对 CM 量的频域行为进行了研究，揭示了输入和输出 CM 量之间的关系以及 CM 电压和 CM 电流之间的关系等重要问题。
{"title":"Investigations Into Conducted Emissions of a 10-kW Photovoltaic Plant","authors":"Makarand M. Kane;Nathaniel Taylor;Daniel Månsson","doi":"10.1109/LEMCPA.2024.3359485","DOIUrl":"https://doi.org/10.1109/LEMCPA.2024.3359485","url":null,"abstract":"Considering the inverter as the source of electromagnetic emission signals in a photovoltaic (PV) plant, a comprehensive set of measurements of conducted emissions at the input and output of the inverter in a 10-kW PV plant are presented. These are particularly relevant on the backdrop of 1) the ban of products in the EU market due to noncompliance and 2) the increased switching frequency in the inverters \u0000<inline-formula> <tex-math>$(sim 100$ </tex-math></inline-formula>\u0000 s of kHz) in the near future. Specifically, the common-mode (CM) and differential-mode (DM) currents and voltages are measured, and their frequency-domain behavior is studied. It is suggested that conducted emissions from PV can be classified into three zones: 1) extremely low-frequency (ELF) zone, 2) power frequency zone, and 3) switching frequency zone. Important observations from this exercise are the measurement of harmonic contents of current with total rated current distortion (TRD), imbalance in the output voltage, and low-frequency ripples in the dc voltage. Frequency-domain behavior of the CM quantities is studied which throws light on important points like a relation between input and output CM quantities and a relation between CM voltage and CM current.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"16-21"},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067534","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 : 2024-01-26DOI: 10.1109/LEMCPA.2024.3359149
Punyatoya Routray;Debalina Ghosh
This letter introduces a novel multilayer metamaterial absorber design suitable for multiband applications in the C, X, and Ku frequency bands. The absorber’s compact nature, wide oblique angle coverage, and insensitivity to polarization angles make it a versatile solution. This absorber is designed by stacking two dual-band metamaterial absorbers. The upper layer incorporates a design composed of four concentric rings loaded in a cross configuration. Meanwhile, the middle layer is formed with two sets of embedded rings and split rings, all centered around a crossed rod. The absorber exhibits absorption peaks above 90% in the frequency bands of operation. Importantly, its performance remains consistent across varying polarization angles and is capable of sustaining absorptivity exceeding 90% at oblique angles of up to 60° for both transverse electric (TE) and transverse magnetic (TM) modes. A comprehensive model is established to elucidate the absorption mechanism and investigate the interplay between geometric characteristics and absorptivity. This model aids in adapting the structure to specific frequency requirements. Practical fabrication is accomplished using a straightforward printed-circuit board fabrication technique. Experimental measurements closely align with the anticipated performance, validating the effectiveness of the proposed multilayer absorber design.
这封信介绍了一种适用于 C、X 和 Ku 频段多频带应用的新型多层超材料吸收器设计。这种吸收器结构紧凑，斜角覆盖范围大，对偏振角不敏感，是一种多功能解决方案。这种吸收器是通过堆叠两个双频超材料吸收器设计而成。上层采用了由四个同心环组成的交叉配置设计。同时，中间层由两组嵌入环和分裂环组成，所有环都围绕着一根交叉杆。该吸收器在工作频段的吸收峰值超过 90%。重要的是，它的性能在不同的极化角下保持一致，并且在横向电（TE）和横向磁（TM）模式下，能在高达 60° 的斜角上保持超过 90% 的吸收率。我们建立了一个综合模型来阐明吸收机制，并研究几何特性与吸收率之间的相互作用。该模型有助于根据特定频率要求调整结构。实际制造采用简单的印刷电路板制造技术。实验测量结果与预期性能非常吻合，验证了所建议的多层吸收器设计的有效性。
{"title":"Design and Modeling of a Miniaturized Multilayer Metamaterial Absorber With Oblique Angle and Polarization Insensitivity","authors":"Punyatoya Routray;Debalina Ghosh","doi":"10.1109/LEMCPA.2024.3359149","DOIUrl":"https://doi.org/10.1109/LEMCPA.2024.3359149","url":null,"abstract":"This letter introduces a novel multilayer metamaterial absorber design suitable for multiband applications in the C, X, and Ku frequency bands. The absorber’s compact nature, wide oblique angle coverage, and insensitivity to polarization angles make it a versatile solution. This absorber is designed by stacking two dual-band metamaterial absorbers. The upper layer incorporates a design composed of four concentric rings loaded in a cross configuration. Meanwhile, the middle layer is formed with two sets of embedded rings and split rings, all centered around a crossed rod. The absorber exhibits absorption peaks above 90% in the frequency bands of operation. Importantly, its performance remains consistent across varying polarization angles and is capable of sustaining absorptivity exceeding 90% at oblique angles of up to 60° for both transverse electric (TE) and transverse magnetic (TM) modes. A comprehensive model is established to elucidate the absorption mechanism and investigate the interplay between geometric characteristics and absorptivity. This model aids in adapting the structure to specific frequency requirements. Practical fabrication is accomplished using a straightforward printed-circuit board fabrication technique. Experimental measurements closely align with the anticipated performance, validating the effectiveness of the proposed multilayer absorber design.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"29-34"},"PeriodicalIF":0.0,"publicationDate":"2024-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140067563","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}
This letter employs simulation findings to demonstrate the practical reasons why the low-frequency magnetic shielding effectiveness (SE) is different when characterized using two parallel loops (NSA 94-106) or two coplanar loops (IEEE Std. 299). It shows how the change in the loop radius impacts the SE for the NSA 94–106 setup rather than for the IEEE 299 one. The observation is rooted in the difference of the wave impedance for both scenarios. Additionally, this letter elucidates the reason behind the wave impedance difference.
{"title":"Differences Between NSA 94–106 and IEEE Std. 299 Setups for Low-Frequency Magnetic Shielding Effectiveness Characterization: A Study Using Numerical Simulations","authors":"Lirim Koraqi;Tim Claeys;Johan Catrysse;Davy Pissoort","doi":"10.1109/LEMCPA.2024.3355849","DOIUrl":"https://doi.org/10.1109/LEMCPA.2024.3355849","url":null,"abstract":"This letter employs simulation findings to demonstrate the practical reasons why the low-frequency magnetic shielding effectiveness (SE) is different when characterized using two parallel loops (NSA 94-106) or two coplanar loops (IEEE Std. 299). It shows how the change in the loop radius impacts the SE for the NSA 94–106 setup rather than for the IEEE 299 one. The observation is rooted in the difference of the wave impedance for both scenarios. Additionally, this letter elucidates the reason behind the wave impedance difference.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"22-28"},"PeriodicalIF":0.0,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140066436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-29DOI: 10.1109/LEMCPA.2023.3336493
{"title":"2023 Index IEEE Letters on Electromagnetic Compatibility Practice and Applications Vol. 5","authors":"","doi":"10.1109/LEMCPA.2023.3336493","DOIUrl":"https://doi.org/10.1109/LEMCPA.2023.3336493","url":null,"abstract":"","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"5 4","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10334004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138468123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-22DOI: 10.1109/LEMCPA.2023.3325491
{"title":"AI, MACHINE LEARNING, AND DEEP LEARNING: ADVANCES AND APPLICATIONS FOR EMC","authors":"","doi":"10.1109/LEMCPA.2023.3325491","DOIUrl":"https://doi.org/10.1109/LEMCPA.2023.3325491","url":null,"abstract":"","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"5 4","pages":"159-160"},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10325839","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138431299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-22DOI: 10.1109/LEMCPA.2023.3325502
Summary form only: Abstracts of articles presented in this issue of the publication.
仅以摘要形式提供:本刊发表的文章摘要。
{"title":"Synopsis of the December 2023 Issue of the IEEE Letters on Electromagnetic Compatibility Practice and Applications","authors":"","doi":"10.1109/LEMCPA.2023.3325502","DOIUrl":"https://doi.org/10.1109/LEMCPA.2023.3325502","url":null,"abstract":"Summary form only: Abstracts of articles presented in this issue of the publication.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"5 4","pages":"103-107"},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10325836","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138431328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-22DOI: 10.1109/LEMCPA.2023.3332790
{"title":"IEEE ELECTROMAGNETIC COMPATIBILITY SOCIETY","authors":"","doi":"10.1109/LEMCPA.2023.3332790","DOIUrl":"https://doi.org/10.1109/LEMCPA.2023.3332790","url":null,"abstract":"","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"5 4","pages":"C2-C2"},"PeriodicalIF":0.0,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10325659","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138431326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Open transverse electromagnetic (TEM) cells are used for many applications. Usually, such cells are built of metal sheets with linear profiles. Due to these simple geometries, impedance matching is limited. To improve the matching, a simple semianalytical method for an advanced septum profile is developed. Dominant TEM-mode propagation and an expression for the characteristic impedance of a stripline are considered. The characteristic impedances of the feed and the central stripline are equal to a given, desired value. To minimize reflections, the characteristic impedance of the TEM mode is enforced to be constant over the entire structure, especially along the tapered sections. In this way, the proposed method returns the septum width as a function of the longitudinal coordinate along the cell, such that each cross section has a characteristic impedance equal to the given, desired value. A septum designed according to the proposed method is manufactured and installed in a TEM cell prototype. The 30 MHz–1 GHz frequency range is considered to cover CISPR bands C and D. Both measurements and full-wave simulations indicate an improvement in the return loss of 4.6 dB from 10.6 to 15.2 dB with respect to the previously installed linearly tapered septum. Code supporting the findings available at: https://codeocean.com/capsule/4880490/tree .
开放式横向电磁 (TEM) 单元应用广泛。通常情况下，这种电池由具有线性轮廓的金属板制成。由于这些简单的几何形状，阻抗匹配受到限制。为了改善匹配，我们开发了一种先进的隔膜轮廓的简单半解析方法。考虑了主要的 TEM 模式传播和带状线的特性阻抗表达式。馈电和中央带状线的特性阻抗等于给定的理想值。为了最大限度地减少反射，TEM 模式的特性阻抗在整个结构中，尤其是沿锥形部分，必须保持恒定。通过这种方式，所提出的方法可将隔板宽度作为沿单元纵向坐标的函数返回，从而使每个横截面的特性阻抗等于给定的期望值。根据所提方法设计的隔板已制造完成，并安装在 TEM 小室原型中。测量和全波模拟结果表明，与以前安装的线性锥形隔膜相比，回波损耗从 10.6 dB 提高到 15.2 dB，提高了 4.6 dB。支持研究结果的代码见：https://codeocean.com/capsule/4880490/tree。
{"title":"Simple Semianalytical Septum Design for Improved Matching in Open TEM Cells","authors":"Giacomo Giannetti;Christian Spindelberger;Holger Arthaber","doi":"10.1109/LEMCPA.2023.3333003","DOIUrl":"10.1109/LEMCPA.2023.3333003","url":null,"abstract":"Open transverse electromagnetic (TEM) cells are used for many applications. Usually, such cells are built of metal sheets with linear profiles. Due to these simple geometries, impedance matching is limited. To improve the matching, a simple semianalytical method for an advanced septum profile is developed. Dominant TEM-mode propagation and an expression for the characteristic impedance of a stripline are considered. The characteristic impedances of the feed and the central stripline are equal to a given, desired value. To minimize reflections, the characteristic impedance of the TEM mode is enforced to be constant over the entire structure, especially along the tapered sections. In this way, the proposed method returns the septum width as a function of the longitudinal coordinate along the cell, such that each cross section has a characteristic impedance equal to the given, desired value. A septum designed according to the proposed method is manufactured and installed in a TEM cell prototype. The 30 MHz–1 GHz frequency range is considered to cover CISPR bands C and D. Both measurements and full-wave simulations indicate an improvement in the return loss of 4.6 dB from 10.6 to 15.2 dB with respect to the previously installed linearly tapered septum. Code supporting the findings available at: \u0000<uri>https://codeocean.com/capsule/4880490/tree</uri>\u0000.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"6-10"},"PeriodicalIF":0.0,"publicationDate":"2023-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10318185","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135710550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-06DOI: 10.1109/LEMCPA.2023.3330402
Ze Sun;Yansheng Wang;DongHyun Kim
To characterize the radiated noise sources in the radio-frequency interference simulations, a novel equivalent dipole source extraction method was proposed by our group previously. An iteration algorithm and the genetic algorithm work together to reconstruct an equivalent source using near-field magnitude information only while minimizing the number of dipoles needed. In this letter, the previously proposed equivalent dipole extraction algorithm is extended to efficiently extract an equivalent source of harmonics. Furthermore, the algorithm is verified using the actual product instead of simplified test boards. A rigorous and systematic validation process is proposed and conducted, which ensures the robustness and credibility of the extraction algorithm for future applications.
{"title":"System-Level Validation of Radiated Noise Source Characterization Using Only Near-Field Magnitude Information","authors":"Ze Sun;Yansheng Wang;DongHyun Kim","doi":"10.1109/LEMCPA.2023.3330402","DOIUrl":"10.1109/LEMCPA.2023.3330402","url":null,"abstract":"To characterize the radiated noise sources in the radio-frequency interference simulations, a novel equivalent dipole source extraction method was proposed by our group previously. An iteration algorithm and the genetic algorithm work together to reconstruct an equivalent source using near-field magnitude information only while minimizing the number of dipoles needed. In this letter, the previously proposed equivalent dipole extraction algorithm is extended to efficiently extract an equivalent source of harmonics. Furthermore, the algorithm is verified using the actual product instead of simplified test boards. A rigorous and systematic validation process is proposed and conducted, which ensures the robustness and credibility of the extraction algorithm for future applications.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"35-42"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135503785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-24DOI: 10.1109/LEMCPA.2023.3327027
Sourodipto Das;Anil Rajput;Biswajeet Mukherjee
A novel miniaturized unit-cell frequency-selective surface (FSS)-based bandstop filter (BSF) is presented in this letter. The proposed structure exhibits negative refractive index (NRI) characteristics by designing an epsilon-negative FSS. This design gives a 10-dB rejection bandwidth from 3.13 to 4.75 GHz and its unit cell has an electrical length of $0.125,,lambda _{0} times 0.125,,lambda _{0}$ . In addition, the designed BSF has a center frequency of 3.96 GHz and an NRI value for a range of 220 MHz, starting from 4.07 to 4.29 GHz. Furthermore, its equivalent circuit model and surface current distribution are elucidated to explain the behavior of the proposed FSS. The structure manifests polarization-independent characteristics and provides a stable frequency response for normal and oblique angles under both transverse electric (TE) and transverse magnetic (TM) incident polarization. To validate the results, the BSF is fabricated, and good agreement between the simulated and measured responses is observed.
{"title":"A Novel FSS-Based Bandstop Filter for TE/TM Polarization","authors":"Sourodipto Das;Anil Rajput;Biswajeet Mukherjee","doi":"10.1109/LEMCPA.2023.3327027","DOIUrl":"10.1109/LEMCPA.2023.3327027","url":null,"abstract":"A novel miniaturized unit-cell frequency-selective surface (FSS)-based bandstop filter (BSF) is presented in this letter. The proposed structure exhibits negative refractive index (NRI) characteristics by designing an epsilon-negative FSS. This design gives a 10-dB rejection bandwidth from 3.13 to 4.75 GHz and its unit cell has an electrical length of \u0000<inline-formula> <tex-math>$0.125,,lambda _{0} times 0.125,,lambda _{0}$ </tex-math></inline-formula>\u0000. In addition, the designed BSF has a center frequency of 3.96 GHz and an NRI value for a range of 220 MHz, starting from 4.07 to 4.29 GHz. Furthermore, its equivalent circuit model and surface current distribution are elucidated to explain the behavior of the proposed FSS. The structure manifests polarization-independent characteristics and provides a stable frequency response for normal and oblique angles under both transverse electric (TE) and transverse magnetic (TM) incident polarization. To validate the results, the BSF is fabricated, and good agreement between the simulated and measured responses is observed.","PeriodicalId":100625,"journal":{"name":"IEEE Letters on Electromagnetic Compatibility Practice and Applications","volume":"6 1","pages":"11-15"},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135156537","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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