Pub Date : 1992-01-01DOI: 10.1109/ISEMC.1992.626133
V. Arafiles
This paper presents the results of evaluations conducted by the author for the Electromagnetic Compatibility Technical Center (EeTC) on commercially available EMC test systems. These test systems are generally intended for use in CISPR, Mil-Std-462, and FCC Part 15 certification and testing. The intent of the evaluation is to determine if such test systems can be used in EMC surveys at quiet rural receiver sites. The evaluation showed that unmodified commercial EMC test systems are not sensitive enough for surveys in quiet rural areas. The commercial test sets resulted in errors of 15 20 dB higher than actual site noise levels. Antennas with low antenna factors, couplers with low losses, and pre-amplifier/receiver combinations with less than 6 dB noise figures must be used to properly survey quiet receiver sites.
本文介绍了作者为电磁兼容技术中心(EeTC)对市售电磁兼容测试系统进行评估的结果。这些测试系统通常用于CISPR, Mil-Std-462和FCC Part 15认证和测试。评估的目的是确定这种测试系统是否可以用于在安静的农村接收机站点进行EMC调查。评估表明，未经修改的商用电磁兼容测试系统对安静的农村地区的调查不够敏感。商业测试集的误差比实际现场噪声水平高15 - 20分贝。低天线系数的天线、低损耗的耦合器和噪声系数小于6db的前置放大器/接收机组合必须用于正确测量安静的接收机站点。
{"title":"Evaluation Of Commercial Test Sets For Use In EMC Surveys At Quiet Rural Sites","authors":"V. Arafiles","doi":"10.1109/ISEMC.1992.626133","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626133","url":null,"abstract":"This paper presents the results of evaluations conducted by the author for the Electromagnetic Compatibility Technical Center (EeTC) on commercially available EMC test systems. These test systems are generally intended for use in CISPR, Mil-Std-462, and FCC Part 15 certification and testing. The intent of the evaluation is to determine if such test systems can be used in EMC surveys at quiet rural receiver sites. The evaluation showed that unmodified commercial EMC test systems are not sensitive enough for surveys in quiet rural areas. The commercial test sets resulted in errors of 15 20 dB higher than actual site noise levels. Antennas with low antenna factors, couplers with low losses, and pre-amplifier/receiver combinations with less than 6 dB noise figures must be used to properly survey quiet receiver sites.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"1 1","pages":"428-430"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81090530","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626150
R. Renninger
A new method for system-level electrostatic discharge (ESD) tests uses the Mean Time Between Undesired Responses (MTBUR) as the ESD immunity criterion. The MTBUR and other related parameters directly measure a system’s reliability in a particular ESD environment. To arrive at the most efficient possible test plan, the technique calculates the minimum number of ESD pulses a system must withstand to verify, with a specified statistical confidence level, that it has a given MTBUR in a given ESD environment.
{"title":"Ptimized Statistical Method For System-level ESD Tests","authors":"R. Renninger","doi":"10.1109/ISEMC.1992.626150","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626150","url":null,"abstract":"A new method for system-level electrostatic discharge (ESD) tests uses the Mean Time Between Undesired Responses (MTBUR) as the ESD immunity criterion. The MTBUR and other related parameters directly measure a system’s reliability in a particular ESD environment. To arrive at the most efficient possible test plan, the technique calculates the minimum number of ESD pulses a system must withstand to verify, with a specified statistical confidence level, that it has a given MTBUR in a given ESD environment.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"92 2 1","pages":"474-484"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78612058","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626081
S. Hwu, J. S. Fournet, D. Eggers, G. Arndt
There are great concerns about the possible high levels o f electromagnetic interference produced by the high power dipole antenna on the Waves in Space Plasma (WISP) payload. This paper presents the results of an initial analysis o f the electric and magnetic field strength in the space shuttle cargo bay. Methods of predicting electromagnetic field strengths in the Shuttle cargo bay are also discussed.
{"title":"Space Shuttle EMI Analysis: Electromagnetic Field Strength Around Wisp Payload","authors":"S. Hwu, J. S. Fournet, D. Eggers, G. Arndt","doi":"10.1109/ISEMC.1992.626081","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626081","url":null,"abstract":"There are great concerns about the possible high levels o f electromagnetic interference produced by the high power dipole antenna on the Waves in Space Plasma (WISP) payload. This paper presents the results of an initial analysis o f the electric and magnetic field strength in the space shuttle cargo bay. Methods of predicting electromagnetic field strengths in the Shuttle cargo bay are also discussed.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"4 1","pages":"219-222"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73780571","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626072
P. Richman
European standards for Pulsed EM1 have gained major importance via the IEC 801 series of immunity standards. They are being turned into mandatory ENS, or European Norms. These IEC 801 standards include 801-211991 for ESD (Electrostatic Discharge) 801-411988 for EFT (Electrical Fast Transients) , and 801-51 (draft) for SURGE. [+,2,3] It is clear that these standards will become worldwide requirements, since companies doing business in Europe will have to meet them. It can be anticipated that they will supplant individual national standards in one way or another, since there will be significant resistance to testing equipment twice.
{"title":"Testing Equipment Properly To The New Pulsed EMI Standards","authors":"P. Richman","doi":"10.1109/ISEMC.1992.626072","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626072","url":null,"abstract":"European standards for Pulsed EM1 have gained major importance via the IEC 801 series of immunity standards. They are being turned into mandatory ENS, or European Norms. These IEC 801 standards include 801-211991 for ESD (Electrostatic Discharge) 801-411988 for EFT (Electrical Fast Transients) , and 801-51 (draft) for SURGE. [+,2,3] It is clear that these standards will become worldwide requirements, since companies doing business in Europe will have to meet them. It can be anticipated that they will supplant individual national standards in one way or another, since there will be significant resistance to testing equipment twice.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"22 1","pages":"174-179"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81059106","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626101
A. Tsaliovich
Cable and connector shielding performance evaluation is addressed from the most general positions. A brief revisit of the shielding physics emphasizes three main electromagnetic coupling and energy transfer phenomena to be considered on different system levels: electronic system as a whole, cable/connector assembly, and shield proper. It is postulated that there is no universal test method, equally applicable to all system levels and shield working conditions. Therefore, the 'various shield evaluation needs must be met using different techniques. Though generally these techniques are not equivalent and serve different purposes, they can be brought to a "common denominator" by using reference calibrators. Possible physical nature of the reference calibrators is considered and highlights of a shielding effectiveness test guide are suggested.
{"title":"Cable And Connector Shielding Test: A Blueprint For A Standard","authors":"A. Tsaliovich","doi":"10.1109/ISEMC.1992.626101","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626101","url":null,"abstract":"Cable and connector shielding performance evaluation is addressed from the most general positions. A brief revisit of the shielding physics emphasizes three main electromagnetic coupling and energy transfer phenomena to be considered on different system levels: electronic system as a whole, cable/connector assembly, and shield proper. It is postulated that there is no universal test method, equally applicable to all system levels and shield working conditions. Therefore, the 'various shield evaluation needs must be met using different techniques. Though generally these techniques are not equivalent and serve different purposes, they can be brought to a \"common denominator\" by using reference calibrators. Possible physical nature of the reference calibrators is considered and highlights of a shielding effectiveness test guide are suggested.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"56 1","pages":"315-320"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91289814","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 : 1992-01-01DOI: 10.1109/isemc.1992.626065
M. Hatfield, G.J. Frever
This paper presents shielding effectiveness data for five separate gaskets taken using a “nested” mode-stirred chamber technique. The gaskets used were the same as those used in Part I of this paper, which evaluated the gaskets using the Transfer Impedance technique. Length normalized data obtained with both techniques are presented for the five gaskets.
{"title":"Comparison of gasket transfer impedance and shielding effectiveness measurements - Part II","authors":"M. Hatfield, G.J. Frever","doi":"10.1109/isemc.1992.626065","DOIUrl":"https://doi.org/10.1109/isemc.1992.626065","url":null,"abstract":"This paper presents shielding effectiveness data for five separate gaskets taken using a “nested” mode-stirred chamber technique. The gaskets used were the same as those used in Part I of this paper, which evaluated the gaskets using the Transfer Impedance technique. Length normalized data obtained with both techniques are presented for the five gaskets.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"41 1","pages":"142-148"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87533314","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626048
R. Manke, P. Wong, T. Cooprider, J. Lebaric
Finite D@rence(FD) technique is applied to qirusi-TEM electronlagtietic fields to calculate induced currents on purullel truces of a printed wiring board and visualize c.ro.ss-sec.tioti~i1 electric und magnetic field vectors. The cwiipirter code was developed fo r iise in a MATLAB environnient, allowing portability and' exchange between various p1atforni.s running M A T U B . Open-boundary conditions are siniulated irsing Transparent Grid Termination (TGT) technique. Induced current data and vector plots are given for severul geometries involving printed wiring board truces positioned differently with respect to each other. Introduction The objectives are to calculate cuments and potentials induced on parallel traces of a printed wiring board (PWB) and visualize the electric and magnetic field clistribut.ions for PWB cross-sections. I t is assumed that there is no field variation with respect to one coordinate, the one in the direction of propagation, such that problem can be treated as two-dimensional (2-D). This is the s,o-called quasi-TEM approximation for inhomogeneous domains. Typical configuration we have analyzed involves, a dielectric substrate of known permittivity with two narrow PEC strips and a wider PEC ground plane. One strip is "active" with a known potential difference imposed between the strip andl the ground plane, as if the strip were driven by an ideal voltage source. The current on the active strip is not known, and depeinds on the impedance that the strip presents to the source. The other strip is "quiet"and neither its induced potential nor its induced current are known. The physical proximity of the quiet strip alters the current on the active strip and a current and a potential are induced on the quiet strip. The two strips are either in the same plane ("cdgc coupling"), or one of the strips is "buried" in the substr;ite. iis c;in bc the case with niulti-layered boards. 'l'lic induced current on the qiiiel strip is noriiwlized to the current on the active strip to obtain the "induced current cocflicient". Similarly, the induced volliige coefficient isdefined as the ratio of~t ie iritlucctl potenti:il on thc quiet strip to he potential ofthc xtivc strip. The two coefficients depend on the spacing between the strips, and decrease monotonically as the spacing is increased. We have investigated the dependence of these coefficients on the position and spacing of the strips. Nu me rical Tech n i a Standard Finite Difference technique is employed to calculated the potentials on a cross-section. A uniform, square FD grid is ussuined. Laplace's equation is solved in 2-D, subject to a simulated open-boundary condition and a known potential on the active strip. Since we have used well-known FD equations for the potentials, the FD details will be omitted. The system of FD equations, with proper source and boundary conditions, is solved for the unknown potentials. The potential solution is then used to find the electric field as the n
{"title":"Numerical Solution Of Induced Currents On Printed Wiring Boards","authors":"R. Manke, P. Wong, T. Cooprider, J. Lebaric","doi":"10.1109/ISEMC.1992.626048","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626048","url":null,"abstract":"Finite D@rence(FD) technique is applied to qirusi-TEM electronlagtietic fields to calculate induced currents on purullel truces of a printed wiring board and visualize c.ro.ss-sec.tioti~i1 electric und magnetic field vectors. The cwiipirter code was developed fo r iise in a MATLAB environnient, allowing portability and' exchange between various p1atforni.s running M A T U B . Open-boundary conditions are siniulated irsing Transparent Grid Termination (TGT) technique. Induced current data and vector plots are given for severul geometries involving printed wiring board truces positioned differently with respect to each other. Introduction The objectives are to calculate cuments and potentials induced on parallel traces of a printed wiring board (PWB) and visualize the electric and magnetic field clistribut.ions for PWB cross-sections. I t is assumed that there is no field variation with respect to one coordinate, the one in the direction of propagation, such that problem can be treated as two-dimensional (2-D). This is the s,o-called quasi-TEM approximation for inhomogeneous domains. Typical configuration we have analyzed involves, a dielectric substrate of known permittivity with two narrow PEC strips and a wider PEC ground plane. One strip is \"active\" with a known potential difference imposed between the strip andl the ground plane, as if the strip were driven by an ideal voltage source. The current on the active strip is not known, and depeinds on the impedance that the strip presents to the source. The other strip is \"quiet\"and neither its induced potential nor its induced current are known. The physical proximity of the quiet strip alters the current on the active strip and a current and a potential are induced on the quiet strip. The two strips are either in the same plane (\"cdgc coupling\"), or one of the strips is \"buried\" in the substr;ite. iis c;in bc the case with niulti-layered boards. 'l'lic induced current on the qiiiel strip is noriiwlized to the current on the active strip to obtain the \"induced current cocflicient\". Similarly, the induced volliige coefficient isdefined as the ratio of~t ie iritlucctl potenti:il on thc quiet strip to he potential ofthc xtivc strip. The two coefficients depend on the spacing between the strips, and decrease monotonically as the spacing is increased. We have investigated the dependence of these coefficients on the position and spacing of the strips. Nu me rical Tech n i a Standard Finite Difference technique is employed to calculated the potentials on a cross-section. A uniform, square FD grid is ussuined. Laplace's equation is solved in 2-D, subject to a simulated open-boundary condition and a known potential on the active strip. Since we have used well-known FD equations for the potentials, the FD details will be omitted. The system of FD equations, with proper source and boundary conditions, is solved for the unknown potentials. The potential solution is then used to find the electric field as the n","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"32 1","pages":"53-61"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79204572","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626042
Andrea Broaddus, Gerhard Kunkel
{"title":"Shielding effectiveness test results of aluminized mylar","authors":"Andrea Broaddus, Gerhard Kunkel","doi":"10.1109/ISEMC.1992.626042","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626042","url":null,"abstract":"","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"112 1","pages":"21-26"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79558166","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 : 1992-01-01DOI: 10.1109/ISEMC.1992.626159
R. Stoner
With the continued need to use commercial off-the-shelf equipment, the EM1 impact must be considered. The responsibility of meeting contractual requirements for EM1 standards using commercial equipment usually falls on the contractor. This can have a major cost impact on any program using these EM1 standards. Case histories show omission of specific EM1 requirements caused failures during EM1 testing. This has had a cost impact on these programs.
{"title":"Impact Of The Use Of Commercial Off-the-shelf Equipment On The Requirements For Electromagnetic Interference (EMI) Control","authors":"R. Stoner","doi":"10.1109/ISEMC.1992.626159","DOIUrl":"https://doi.org/10.1109/ISEMC.1992.626159","url":null,"abstract":"With the continued need to use commercial off-the-shelf equipment, the EM1 impact must be considered. The responsibility of meeting contractual requirements for EM1 standards using commercial equipment usually falls on the contractor. This can have a major cost impact on any program using these EM1 standards. Case histories show omission of specific EM1 requirements caused failures during EM1 testing. This has had a cost impact on these programs.","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"6 1","pages":"518-519"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84410226","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 : 1990-08-21DOI: 10.1109/ISEMC.1990.252784
S. Cristina, A. Orlandi
A procedure is presented for the analysis of the electromagnetic field inside a structure which receives a direct lightning stroke. The lightning protection system is schematized as an equivalent wire model. The electromagnetic field inside the structure is computed by means of a digital computation code based upon the moments method in the framework of the thin-wire approximation. The present work aims at the characterization of the influence of the field radiated by the lightning channel, on the electromagnetic field inside the building, which is subject to a direct stroke. The lightning channel is simulated by means of a rectilinear vertical antenna having a suitable height. The results of the analysis indicate that the lightning channel has a significant effect.<>
{"title":"Lightning channel's influence on currents and electromagnetic fields in a building struck by lightning","authors":"S. Cristina, A. Orlandi","doi":"10.1109/ISEMC.1990.252784","DOIUrl":"https://doi.org/10.1109/ISEMC.1990.252784","url":null,"abstract":"A procedure is presented for the analysis of the electromagnetic field inside a structure which receives a direct lightning stroke. The lightning protection system is schematized as an equivalent wire model. The electromagnetic field inside the structure is computed by means of a digital computation code based upon the moments method in the framework of the thin-wire approximation. The present work aims at the characterization of the influence of the field radiated by the lightning channel, on the electromagnetic field inside the building, which is subject to a direct stroke. The lightning channel is simulated by means of a rectilinear vertical antenna having a suitable height. The results of the analysis indicate that the lightning channel has a significant effect.<<ETX>>","PeriodicalId":93568,"journal":{"name":"IEEE International Symposium on Electromagnetic Compatibility : [proceedings]. IEEE International Symposium on Electromagnetic Compatibility","volume":"74 1","pages":"338-342"},"PeriodicalIF":0.0,"publicationDate":"1990-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73882446","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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