Pub Date : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396865
H. Kapitza, H. Eckoldt, M. Faesing
The European X-Ray Free Electron Laser (XFEL) research facility is currently being built at Deutsches Elektronensynchrotron (DESY) in Hamburg, Germany. In this large underground facility high power RF stations are operated next to high precision diagnostics instruments. This made electromagnetic compatibility (EMC) an important issue from the very beginning of the project. A well-designed grounding system with a hierarchical structure is an essential ingredient for safety and EMC. Important parts of the facility ground were implemented in the course of the civil construction work. The specialties of tunnel boring and building far below the ground water level had to be taken into account. Some aspects of facility grounding were investigated at the free electron laser facility FLASH which operates for users at DESY for some years.
{"title":"Grounding for EMC at the European XFEL","authors":"H. Kapitza, H. Eckoldt, M. Faesing","doi":"10.1109/EMCEUROPE.2012.6396865","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396865","url":null,"abstract":"The European X-Ray Free Electron Laser (XFEL) research facility is currently being built at Deutsches Elektronensynchrotron (DESY) in Hamburg, Germany. In this large underground facility high power RF stations are operated next to high precision diagnostics instruments. This made electromagnetic compatibility (EMC) an important issue from the very beginning of the project. A well-designed grounding system with a hierarchical structure is an essential ingredient for safety and EMC. Important parts of the facility ground were implemented in the course of the civil construction work. The specialties of tunnel boring and building far below the ground water level had to be taken into account. Some aspects of facility grounding were investigated at the free electron laser facility FLASH which operates for users at DESY for some years.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"118 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115168589","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396859
H. Azizi, F. Belkacem, D. Moussaoui, M. Bensetti
This paper presents a detailed study of the shielding effectiveness properties of rectangular enclosures with apertures, by using a numerical method (FDTD). Both the magnetic and electric shielding was calculated as a function of frequency, enclosure dimensions, different apertures shapes, plane wave incidence mode and positions within the enclosure. Also the “loaded aperture” approach was investigated. The results of shielding effectiveness predictions obtained by the numerical method are compared and validated with full-field simulations using software CST.
{"title":"Numerical study for the shielding effectiveness of a rectangular enclosure with apertures","authors":"H. Azizi, F. Belkacem, D. Moussaoui, M. Bensetti","doi":"10.1109/EMCEUROPE.2012.6396859","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396859","url":null,"abstract":"This paper presents a detailed study of the shielding effectiveness properties of rectangular enclosures with apertures, by using a numerical method (FDTD). Both the magnetic and electric shielding was calculated as a function of frequency, enclosure dimensions, different apertures shapes, plane wave incidence mode and positions within the enclosure. Also the “loaded aperture” approach was investigated. The results of shielding effectiveness predictions obtained by the numerical method are compared and validated with full-field simulations using software CST.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117064719","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396881
K. Ikemiya, M. Kanazawa, T. Sudo, S. Masuda, Y. Hirakawa, K. Wada
Three dimensionally stacked package using FFCSP (Flexible carrier Folded real Chip Size Package) has been developed as one solution of high-density DRAM module. FPC (Flexible printed circuit) was effectively utilized to construct the pads at the both top and bottom sides of PoP (package-on-package) structure. In such multi-tiered package structures, the power supply stability for the upper tiered package is estimated to be worse than that of the lower tiered package due to parasitic inductance. In this paper, the co-analysis model including signal integrity (SI) and power integrity (PI) has been established to evaluate the power supply and signal quality among the multi-tiered chips. In particular, the power distribution networks (PDN) and eye diagrams for multi-tiered package were discussed.
{"title":"Co-analysis of signal and power integrity of 3D stacked package using flexible printed circuits","authors":"K. Ikemiya, M. Kanazawa, T. Sudo, S. Masuda, Y. Hirakawa, K. Wada","doi":"10.1109/EMCEUROPE.2012.6396881","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396881","url":null,"abstract":"Three dimensionally stacked package using FFCSP (Flexible carrier Folded real Chip Size Package) has been developed as one solution of high-density DRAM module. FPC (Flexible printed circuit) was effectively utilized to construct the pads at the both top and bottom sides of PoP (package-on-package) structure. In such multi-tiered package structures, the power supply stability for the upper tiered package is estimated to be worse than that of the lower tiered package due to parasitic inductance. In this paper, the co-analysis model including signal integrity (SI) and power integrity (PI) has been established to evaluate the power supply and signal quality among the multi-tiered chips. In particular, the power distribution networks (PDN) and eye diagrams for multi-tiered package were discussed.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123414972","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396904
V. De Santis, M. Douglas, N. Kuster, X. L. Chen
In this paper, the impact of the skin modeling and displacement currents on the induced electric field evaluated by low frequency solvers has been investigated. Both a simplified canonical test-case and a realistic hand-touching electrical stimulation have been selected as meaningful applications without any loss of generality. Similar considerations are indeed expected for other induced contact current dosimetry applications. The modeling of the skin is revealed to play a crucial role and affected also the results in case of neglecting displacement currents. The latter led to maximal errors up to 87 % for the canonical test-case and 16% for the realistic application, while variations up to 86 % in the peak estimated electric fields are obtained inside various tissues when using two different tiers of skin conductivity. A better modeling of the skin from both an electrical and a geometrical point of view is therefore needed. Also, more reliable measurement techniques of tissue dielectric properties are strongly desirable in the low frequency range.
{"title":"Impact of the skin conductivity and displacement currents on LF numerical dosimetry","authors":"V. De Santis, M. Douglas, N. Kuster, X. L. Chen","doi":"10.1109/EMCEUROPE.2012.6396904","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396904","url":null,"abstract":"In this paper, the impact of the skin modeling and displacement currents on the induced electric field evaluated by low frequency solvers has been investigated. Both a simplified canonical test-case and a realistic hand-touching electrical stimulation have been selected as meaningful applications without any loss of generality. Similar considerations are indeed expected for other induced contact current dosimetry applications. The modeling of the skin is revealed to play a crucial role and affected also the results in case of neglecting displacement currents. The latter led to maximal errors up to 87 % for the canonical test-case and 16% for the realistic application, while variations up to 86 % in the peak estimated electric fields are obtained inside various tissues when using two different tiers of skin conductivity. A better modeling of the skin from both an electrical and a geometrical point of view is therefore needed. Also, more reliable measurement techniques of tissue dielectric properties are strongly desirable in the low frequency range.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123691169","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396773
R. Timens, B. van Leersum, R. Bijman, F. Leferink
Power networks and installed equipment onboard of naval ships are required to meet military standards. However, technology in the commercial market grows very fast and the use of Commercial Off The Shelf (COTS) products is economically interesting although they are often not certified against required military standards. To justify the use of COTS regarding power quality, the interaction between the power network and the connected consumers is analyzed with respect to both military and civil standards on a naval vessel. The experiments are carried out during island configuration, i.e. using onboard diesel motor generators only, while the naval vessel was in the `setting to work' phase, so the starting up and testing phase. Such a setting to work phase implies many on/off and unexpected switching events.
{"title":"Voltage quality in a naval vessel power system during island configuration","authors":"R. Timens, B. van Leersum, R. Bijman, F. Leferink","doi":"10.1109/EMCEUROPE.2012.6396773","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396773","url":null,"abstract":"Power networks and installed equipment onboard of naval ships are required to meet military standards. However, technology in the commercial market grows very fast and the use of Commercial Off The Shelf (COTS) products is economically interesting although they are often not certified against required military standards. To justify the use of COTS regarding power quality, the interaction between the power network and the connected consumers is analyzed with respect to both military and civil standards on a naval vessel. The experiments are carried out during island configuration, i.e. using onboard diesel motor generators only, while the naval vessel was in the `setting to work' phase, so the starting up and testing phase. Such a setting to work phase implies many on/off and unexpected switching events.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115243820","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396716
J. Carlsson, K. Karlsson, A. Johansson
In this paper we revisit existing methods for measuring the shielding effectiveness of material samples using nested reverberation chambers. These methods have the advantage of exposing the sample with a more realistic environment than other methods that are based on single plane wave excitation. That is, in the reverberation chamber the sample is exposed to fields with different incidence directions and polarizations resulting in that the average shielding effectiveness can be measured. We show by comparison with aperture theory that the measured shielding effectiveness corresponds to the theoretical value. We show also by measurements that a corrugation or choke on the periphery of an aperture can be used for increasing the shielding effectiveness for a narrow frequency range.
{"title":"Validation of shielding effectiveness measurement method using nested reverberation chambers by comparison with aperture theory","authors":"J. Carlsson, K. Karlsson, A. Johansson","doi":"10.1109/EMCEUROPE.2012.6396716","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396716","url":null,"abstract":"In this paper we revisit existing methods for measuring the shielding effectiveness of material samples using nested reverberation chambers. These methods have the advantage of exposing the sample with a more realistic environment than other methods that are based on single plane wave excitation. That is, in the reverberation chamber the sample is exposed to fields with different incidence directions and polarizations resulting in that the average shielding effectiveness can be measured. We show by comparison with aperture theory that the measured shielding effectiveness corresponds to the theoretical value. We show also by measurements that a corrugation or choke on the periphery of an aperture can be used for increasing the shielding effectiveness for a narrow frequency range.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115438090","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396901
N. Ptitsyna, A. Ponzetto
The recent tendency to move from conventional combustion-based mobility to electric mobility poses many questions, some of which are connected to electromagnetic compatibility. In view of this it became necessary to measure and evaluate magnetic field inside electric mobility systems. We present here results of our study of magnetic fields on different electrified transport systems (electric trains, metro, trams and trolleybus) and compare them with scanty information on magnetic fields onboard electric/hybrid cars.
{"title":"Magnetic fields encountered in electric transport: Rail systems, trolleybus and cars","authors":"N. Ptitsyna, A. Ponzetto","doi":"10.1109/EMCEUROPE.2012.6396901","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396901","url":null,"abstract":"The recent tendency to move from conventional combustion-based mobility to electric mobility poses many questions, some of which are connected to electromagnetic compatibility. In view of this it became necessary to measure and evaluate magnetic field inside electric mobility systems. We present here results of our study of magnetic fields on different electrified transport systems (electric trains, metro, trams and trolleybus) and compare them with scanty information on magnetic fields onboard electric/hybrid cars.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115576939","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396824
B. Audone, O. Losito, R. Colombo
The calibration of EMC antenna has always been a frustrating subject for most EMC laboratories. On the other hand in many cases EMC antennas are recalibrated when it is not strictly necessary. This paper proposes a procedure to establish when EMI antennas shall be calibrated on the basis of technical considerations without making reference to abstract quality assurance rules. It seems more correct to stipulate the definition of the calibration time intervals on the basis of a statistical approach comparing the past performance characteristics with the present ones. The reflection coefficient at the antenna input terminal is monitored over the frequency range of interest at regular time intervals to detect whether a modification has occurred; only if this modification is beyond the assumed tolerance limits the antenna shall be calibrated. The procedure illustrated in this paper is in line with the well accepted use of control charts described in quality assurance documents; it has been modified from the standard methods to take into account the specific characteristics of EMI antennas.
{"title":"The definition of the EMC antenna calibration time intervals","authors":"B. Audone, O. Losito, R. Colombo","doi":"10.1109/EMCEUROPE.2012.6396824","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396824","url":null,"abstract":"The calibration of EMC antenna has always been a frustrating subject for most EMC laboratories. On the other hand in many cases EMC antennas are recalibrated when it is not strictly necessary. This paper proposes a procedure to establish when EMI antennas shall be calibrated on the basis of technical considerations without making reference to abstract quality assurance rules. It seems more correct to stipulate the definition of the calibration time intervals on the basis of a statistical approach comparing the past performance characteristics with the present ones. The reflection coefficient at the antenna input terminal is monitored over the frequency range of interest at regular time intervals to detect whether a modification has occurred; only if this modification is beyond the assumed tolerance limits the antenna shall be calibrated. The procedure illustrated in this paper is in line with the well accepted use of control charts described in quality assurance documents; it has been modified from the standard methods to take into account the specific characteristics of EMI antennas.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122342688","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396698
G. Gradoni, T. Antonsen, S. Anlage, E. Ott
We investigate the mode admittance matrix of an aperture radiating inside a wave-chaotic cavity. The closed electromagnetic system is modeled by a statistical description involving chaotic modes and spectra developed in the framework of random matrix theory. It is shown that the random coupling model, previously derived for modeling port and antenna impedances, is also valid for apertures. The universal fluctuation matrix, expressing the coupling between aperture and cavity modes, is found to be diagonalized by the free-space radiation conductance. We propose a procedure exploiting the Hilbert transform to derive the radiation susceptance, also accounting for the magnetostatic contribution, and thus to compose the full radiation admittance matrix. Wave chaos is found to break aperture orthogonality of certain mode configurations. The model gives a unified picture bridging deterministic theories of aperture radiation, and statistical models necessary for capturing chaotic scattering inside complex cavities. Results are of interest for predicting the field coupled through apertures in complex cavities such as reverberation chambers, and for quantifying interferences inside slotted enclosures containing electronic circuitry, among other practical scenarios.
{"title":"Theoretical analysis of apertures radiating inside wave chaotic cavities","authors":"G. Gradoni, T. Antonsen, S. Anlage, E. Ott","doi":"10.1109/EMCEUROPE.2012.6396698","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396698","url":null,"abstract":"We investigate the mode admittance matrix of an aperture radiating inside a wave-chaotic cavity. The closed electromagnetic system is modeled by a statistical description involving chaotic modes and spectra developed in the framework of random matrix theory. It is shown that the random coupling model, previously derived for modeling port and antenna impedances, is also valid for apertures. The universal fluctuation matrix, expressing the coupling between aperture and cavity modes, is found to be diagonalized by the free-space radiation conductance. We propose a procedure exploiting the Hilbert transform to derive the radiation susceptance, also accounting for the magnetostatic contribution, and thus to compose the full radiation admittance matrix. Wave chaos is found to break aperture orthogonality of certain mode configurations. The model gives a unified picture bridging deterministic theories of aperture radiation, and statistical models necessary for capturing chaotic scattering inside complex cavities. Results are of interest for predicting the field coupled through apertures in complex cavities such as reverberation chambers, and for quantifying interferences inside slotted enclosures containing electronic circuitry, among other practical scenarios.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128728801","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 : 2012-12-31DOI: 10.1109/EMCEUROPE.2012.6396894
D. Micu, L. Czumbil, M. Prsa, K. Kasas-Lazetic
A user friendly software application was developed to study the electromagnetic interference problem between high voltage power lines and underground metallic pipelines. The dedicated developed InterfStud software was based also on the development of the magnetic vector potential and current distribution within the soil formulas. The best way to investigate the soil behavior as a conducting media is to determine the current distribution within the soil. New analytical formulas for the induced magnetic vector potential and current distribution in soil are derived. The determined formulas contain semi-infinite integral terms which will be evaluated. We might seek approximations of the semi-infinite integrals by replacing an exponential or algebraic function, the objective being to permit analytic integration. Since there is no good systematic method for making these replacements, their success depends directly on the intuition and ingenuity, taking into account that in practice the integrand has limited accuracy.
{"title":"Interfstud electromagnetic interference software: An accurate evaluation of current distribution in soil and in underground pipelines","authors":"D. Micu, L. Czumbil, M. Prsa, K. Kasas-Lazetic","doi":"10.1109/EMCEUROPE.2012.6396894","DOIUrl":"https://doi.org/10.1109/EMCEUROPE.2012.6396894","url":null,"abstract":"A user friendly software application was developed to study the electromagnetic interference problem between high voltage power lines and underground metallic pipelines. The dedicated developed InterfStud software was based also on the development of the magnetic vector potential and current distribution within the soil formulas. The best way to investigate the soil behavior as a conducting media is to determine the current distribution within the soil. New analytical formulas for the induced magnetic vector potential and current distribution in soil are derived. The determined formulas contain semi-infinite integral terms which will be evaluated. We might seek approximations of the semi-infinite integrals by replacing an exponential or algebraic function, the objective being to permit analytic integration. Since there is no good systematic method for making these replacements, their success depends directly on the intuition and ingenuity, taking into account that in practice the integrand has limited accuracy.","PeriodicalId":377100,"journal":{"name":"International Symposium on Electromagnetic Compatibility - EMC EUROPE","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128658981","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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