Pub Date : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889631
Denys Pokotilov, R. Vogt-Ardatjew, F. Leferink
Nowadays the majority of electrical devices are complex systems with different operation modes and switching elements. The amount of evaluation procedures that are needed to be done for these devices increases drastically. It is pushing standard radiated EMI measurements to the edge, where the advantage between time and the accuracy of measurements should be chosen. Standard low-frequency measurements as CISPR 36, used to evaluate radiated EMI for frequencies below 30 MHz, became too time-consuming and expensive. Proposed improvements which include time-domain multichannel measurements in combination with a three-axis shielded loop antenna can be more time-efficient. Compared to a conventional single-loop antenna, one of the potential challenges is the coupling between loops for the two- and three-axis antenna. This paper investigates the effect of coupling between the individual loops when illuminated with a complex field, which is shown to be the worst-case scenario. Only some minor coupling is observed implying that such a three-axis loop antenna can be used without sacrificing much accuracy, while still providing a significant improvement in the measurement time-efficiency.
{"title":"Evaluation of Three-Axis Magnetic Loop Antenna Cross Coupling for Low-Frequency Measurements","authors":"Denys Pokotilov, R. Vogt-Ardatjew, F. Leferink","doi":"10.1109/EMCSI39492.2022.9889631","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889631","url":null,"abstract":"Nowadays the majority of electrical devices are complex systems with different operation modes and switching elements. The amount of evaluation procedures that are needed to be done for these devices increases drastically. It is pushing standard radiated EMI measurements to the edge, where the advantage between time and the accuracy of measurements should be chosen. Standard low-frequency measurements as CISPR 36, used to evaluate radiated EMI for frequencies below 30 MHz, became too time-consuming and expensive. Proposed improvements which include time-domain multichannel measurements in combination with a three-axis shielded loop antenna can be more time-efficient. Compared to a conventional single-loop antenna, one of the potential challenges is the coupling between loops for the two- and three-axis antenna. This paper investigates the effect of coupling between the individual loops when illuminated with a complex field, which is shown to be the worst-case scenario. Only some minor coupling is observed implying that such a three-axis loop antenna can be used without sacrificing much accuracy, while still providing a significant improvement in the measurement time-efficiency.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125772504","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889640
J. Butterfield, R. Horton
This paper develops an approach using electromagnetic transients (EMT)-type software tools to perform electromagnetic pulse coupling analysis of arbitrarily oriented above-ground cabling systems. The proposed approach allows modeling of large, complex systems such as cabling systems within electrical substations with less complexity than previous methods. Additionally, the approach allows non-linear elements to be included in the model. The results from simulations using the proposed method are compared with results from testing of a four-conductor cabling system inside an RS-105 guided wave test facility.
{"title":"Simulation of EMP Coupling Using Electromagnetic Transient Solvers","authors":"J. Butterfield, R. Horton","doi":"10.1109/EMCSI39492.2022.9889640","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889640","url":null,"abstract":"This paper develops an approach using electromagnetic transients (EMT)-type software tools to perform electromagnetic pulse coupling analysis of arbitrarily oriented above-ground cabling systems. The proposed approach allows modeling of large, complex systems such as cabling systems within electrical substations with less complexity than previous methods. Additionally, the approach allows non-linear elements to be included in the model. The results from simulations using the proposed method are compared with results from testing of a four-conductor cabling system inside an RS-105 guided wave test facility.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116632373","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.10050216
Esha Kondapuram, Chong-Jin Ong, B. Silva, Brandon Lambacher
For a product to be validated with all use cases, several reference designs would be required. This would increase the overall cost and time to market the product. A single reference validation platform solution with limited routing layers utilizing hardware configurable topology options was developed to enable validation. A single High-Speed IO interface was configurable to allow for the validation of three different platform configurations. This paper discusses the signal integrity challenges like interfaces violating the platform design guidelines, includes review of validation data, and review of the mitigation plans for a successfully validated platform.
{"title":"Challenges for Enabling Multiple High-Speed Interfaces On A Reference Validation Platform","authors":"Esha Kondapuram, Chong-Jin Ong, B. Silva, Brandon Lambacher","doi":"10.1109/EMCSI39492.2022.10050216","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.10050216","url":null,"abstract":"For a product to be validated with all use cases, several reference designs would be required. This would increase the overall cost and time to market the product. A single reference validation platform solution with limited routing layers utilizing hardware configurable topology options was developed to enable validation. A single High-Speed IO interface was configurable to allow for the validation of three different platform configurations. This paper discusses the signal integrity challenges like interfaces violating the platform design guidelines, includes review of validation data, and review of the mitigation plans for a successfully validated platform.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124611639","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.10050239
A. Kikitsu, Y. Kurosaki, S. Shirotori, A. Fujita, H. Nishigaki, S. Matsunaka
Metallic/ magnetic multilayer systems using a base unit of $[mathrm{Cu}(100 mathrm{~nm}) / mathrm{NiFeCuMo}(100 mathrm{~nm})] 10$ were investigated as the EMI shielding layer for the sub-100 MHz range. Addition of soft magnetic multilayers was found to exhibit a shielding effect at less than 20 MHz, which may have been originated from domain wall resonance in the base unit. The magneto-static interaction seems to induce magnetic resonances in the other units.
{"title":"Metallic/magnetic Multilayer for Wide-band Direct-on-chip EMI Shielding","authors":"A. Kikitsu, Y. Kurosaki, S. Shirotori, A. Fujita, H. Nishigaki, S. Matsunaka","doi":"10.1109/EMCSI39492.2022.10050239","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.10050239","url":null,"abstract":"Metallic/ magnetic multilayer systems using a base unit of $[mathrm{Cu}(100 mathrm{~nm}) / mathrm{NiFeCuMo}(100 mathrm{~nm})] 10$ were investigated as the EMI shielding layer for the sub-100 MHz range. Addition of soft magnetic multilayers was found to exhibit a shielding effect at less than 20 MHz, which may have been originated from domain wall resonance in the base unit. The magneto-static interaction seems to induce magnetic resonances in the other units.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126816710","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889490
F. de Paulis, Y. Ding, M. Cocchini, C. Hwang, S. Connor, M. Doyle, S. Scearce, W. Becker, A. Ruehli, J. Drewniak
An optimization routine is applied for the decoupling capacitor placement on Power Distribution Networks to identify the limit beyond which the placement of additional decaps is no longer effective, thus leading to wasting layout area and components, and to a cost increase. A specific test example from a real design is used together with the required target impedance and frequency band of interest for the PDN design. The effectiveness of the decap placement while selecting different layers of the stack-up, and while moving the upper limit of the PDN design band is analyzed. Such analysis leads to helpful insights based on the progression of the input impedance during the optimization process, and to develop useful guidelines for avoiding over-design of the PDN.
{"title":"A Methodical Approach for PCB PDN Decoupling Minimizing Overdesign with Genetic Algorithm Optimization","authors":"F. de Paulis, Y. Ding, M. Cocchini, C. Hwang, S. Connor, M. Doyle, S. Scearce, W. Becker, A. Ruehli, J. Drewniak","doi":"10.1109/EMCSI39492.2022.9889490","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889490","url":null,"abstract":"An optimization routine is applied for the decoupling capacitor placement on Power Distribution Networks to identify the limit beyond which the placement of additional decaps is no longer effective, thus leading to wasting layout area and components, and to a cost increase. A specific test example from a real design is used together with the required target impedance and frequency band of interest for the PDN design. The effectiveness of the decap placement while selecting different layers of the stack-up, and while moving the upper limit of the PDN design band is analyzed. Such analysis leads to helpful insights based on the progression of the input impedance during the optimization process, and to develop useful guidelines for avoiding over-design of the PDN.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130685221","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889411
S. Chen, Zhifei Xu, Antoine Moret
The paper examines the primary testing items & procedures of the USB4.1 Gen3 Compliance Test Specification (CTS), i.e., TX test point (TP) 2 test, TX TP3 test, and RX Stress test. The methodology of validating the device under test (DUT) IBIS AMI model against the USB4.1 CTS is described. The roles and impacts of the key parameters are explained and evaluated. A novel approach for inferring the ISI jitter is introduced. The test results obtained through simulation with channels of two representative characteristics are presented. In addition, some concerns associated with the latest standards are discussed, along with proposals for strengthening the clarity of the standard.
{"title":"USB4.1 Compliance Test - Procedures and Issues","authors":"S. Chen, Zhifei Xu, Antoine Moret","doi":"10.1109/EMCSI39492.2022.9889411","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889411","url":null,"abstract":"The paper examines the primary testing items & procedures of the USB4.1 Gen3 Compliance Test Specification (CTS), i.e., TX test point (TP) 2 test, TX TP3 test, and RX Stress test. The methodology of validating the device under test (DUT) IBIS AMI model against the USB4.1 CTS is described. The roles and impacts of the key parameters are explained and evaluated. A novel approach for inferring the ISI jitter is introduced. The test results obtained through simulation with channels of two representative characteristics are presented. In addition, some concerns associated with the latest standards are discussed, along with proposals for strengthening the clarity of the standard.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"2674 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129300279","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889347
Wanshui Yu, Qingmin Li, Zixin Guo, Hanwen Ren, W. H. Siew
For enhancing the lightning protection abilities of wind turbine blades, there is the need to study the mechanical explosion characteristics when the blades suffer from lightning induced arc intrusion. In this paper, a magnetohydrodynamic (MHD) model of lightning induced arc intrusion into the blade was developed, and the airflow and gas pressure distribution were calculated accordingly. The simulation results show that the huge pressure generated at the trailing edge of the blade should be the main cause of the trailing edge cracking. The research presented in this paper provides a theoretical basis for improving the structural design of the blade from the lightning protection perspective.
{"title":"Numerical study on explosion characteristics of wind turbine blade under lightning induced arc","authors":"Wanshui Yu, Qingmin Li, Zixin Guo, Hanwen Ren, W. H. Siew","doi":"10.1109/EMCSI39492.2022.9889347","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889347","url":null,"abstract":"For enhancing the lightning protection abilities of wind turbine blades, there is the need to study the mechanical explosion characteristics when the blades suffer from lightning induced arc intrusion. In this paper, a magnetohydrodynamic (MHD) model of lightning induced arc intrusion into the blade was developed, and the airflow and gas pressure distribution were calculated accordingly. The simulation results show that the huge pressure generated at the trailing edge of the blade should be the main cause of the trailing edge cracking. The research presented in this paper provides a theoretical basis for improving the structural design of the blade from the lightning protection perspective.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"42 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130740972","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889661
Shengxuan Xia, Emmanuel Olugbade, Yuchu He, Yansheng Wang, Hanfeng Wang, Krishna Rao, Marco Poort, Haicheng Zhou, Warren Lee, Nicholas McDonnell, Jonghyun Park, C. Hwang
Modularized designs have been widely used in today's consumer electronic devices and flexible RF springs are used for electrical connections between the modules. In the meantime, aluminum alloy material becomes a common chassis option. It is well known that the oxidized chassis surface introduces a certain level of nonlinearity when contacted by the springs, as known as passive intermodulation (PIM). PIM is one of the well-known root causes of the RF desensitization (desense). This paper is focused on investigating the relationship between PIM and contact conditions of the springs, especially contact area. The PIM level behavior is explained mathematically by the regrowth rate and the RF power distributions on the contacts. Full-wave simulations and mechanical simulations were conducted to further support the hypothesis.
{"title":"Passive Intermodulation Under Different Spring Contact Conditions","authors":"Shengxuan Xia, Emmanuel Olugbade, Yuchu He, Yansheng Wang, Hanfeng Wang, Krishna Rao, Marco Poort, Haicheng Zhou, Warren Lee, Nicholas McDonnell, Jonghyun Park, C. Hwang","doi":"10.1109/EMCSI39492.2022.9889661","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889661","url":null,"abstract":"Modularized designs have been widely used in today's consumer electronic devices and flexible RF springs are used for electrical connections between the modules. In the meantime, aluminum alloy material becomes a common chassis option. It is well known that the oxidized chassis surface introduces a certain level of nonlinearity when contacted by the springs, as known as passive intermodulation (PIM). PIM is one of the well-known root causes of the RF desensitization (desense). This paper is focused on investigating the relationship between PIM and contact conditions of the springs, especially contact area. The PIM level behavior is explained mathematically by the regrowth rate and the RF power distributions on the contacts. Full-wave simulations and mechanical simulations were conducted to further support the hypothesis.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127963133","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.10050249
Patrick DeRoy, Mohit Gopalraj, Sachinkumar Goudnoor, Jay O’Halloran, A. Ramanujan
With the emergence of new high-speed Automotive networking systems using unshielded twisted pair (UTP) cables, the challenges around meeting stringent Automotive requirements have become tougher than ever. Robustness to Automotive transient pulses according to ISO 7637-2 [1], ISO 7637-3 [2] has been a key customer requirement on any networking system physical layer. Several customer specifications also mandate special fixtures to couple the pulses to the communication lines, either the capacitive coupling clamp (CCC) or the 3-slot fixture [3]. This paper studies and compares the effect of these pulses and/or fixtures to help understand the severity on UTP differential data lines.
随着使用非屏蔽双绞线(UTP)电缆的新型高速汽车网络系统的出现，满足严格的汽车要求的挑战变得比以往任何时候都更加严峻。对汽车瞬态脉冲的鲁棒性符合ISO 7637-2 [1]， ISO 7637-3[2]已成为任何网络系统物理层的关键客户要求。一些客户规范还要求特殊夹具将脉冲耦合到通信线路上，要么是电容耦合钳(CCC)，要么是3槽夹具[3]。本文研究并比较了这些脉冲和/或固定装置的影响，以帮助了解UTP差分数据线的严重程度。
{"title":"Automotive Transients Measurement Methodology Assessment for High-Speed Communication Buses","authors":"Patrick DeRoy, Mohit Gopalraj, Sachinkumar Goudnoor, Jay O’Halloran, A. Ramanujan","doi":"10.1109/EMCSI39492.2022.10050249","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.10050249","url":null,"abstract":"With the emergence of new high-speed Automotive networking systems using unshielded twisted pair (UTP) cables, the challenges around meeting stringent Automotive requirements have become tougher than ever. Robustness to Automotive transient pulses according to ISO 7637-2 [1], ISO 7637-3 [2] has been a key customer requirement on any networking system physical layer. Several customer specifications also mandate special fixtures to couple the pulses to the communication lines, either the capacitive coupling clamp (CCC) or the 3-slot fixture [3]. This paper studies and compares the effect of these pulses and/or fixtures to help understand the severity on UTP differential data lines.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"374 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131073883","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 : 2022-08-01DOI: 10.1109/EMCSI39492.2022.9889500
S. Sandler
Power integrity and system engineers have the task of designing, optimizing, and assessing the power distribution network impedance. EM simulators are used to model these networks to optimize the decoupling capacitors and to perform worst case assessments, using simulated dynamic chip currents and applying worst case tolerances. Once the hardware is constructed, measurements are performed for correlation, so that the model can be validated. Many engineers struggle to achieve reasonable part model and circuit model correlation. This paper explores two prevalent reasons for this shortfall and provides a methodology for performing accurate capacitor measurements to achieve these correlations.
{"title":"Capacitor Model Details Key to Measurement Correlation","authors":"S. Sandler","doi":"10.1109/EMCSI39492.2022.9889500","DOIUrl":"https://doi.org/10.1109/EMCSI39492.2022.9889500","url":null,"abstract":"Power integrity and system engineers have the task of designing, optimizing, and assessing the power distribution network impedance. EM simulators are used to model these networks to optimize the decoupling capacitors and to perform worst case assessments, using simulated dynamic chip currents and applying worst case tolerances. Once the hardware is constructed, measurements are performed for correlation, so that the model can be validated. Many engineers struggle to achieve reasonable part model and circuit model correlation. This paper explores two prevalent reasons for this shortfall and provides a methodology for performing accurate capacitor measurements to achieve these correlations.","PeriodicalId":250856,"journal":{"name":"2022 IEEE International Symposium on Electromagnetic Compatibility & Signal/Power Integrity (EMCSI)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129598644","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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