Pub Date : 2015-12-24DOI: 10.1109/LAPC.2015.7366001
Y. Zhang, D. Upton, A. Jaber, H. Ahmed, U. Khan, B. Saeed, P. Mather, P. Lazaridis, R. Atkinson, M. F. Vieira, I. Glover
This paper studies novel localization methods of multiple partial discharge sources in electrical substations. The three compressive sensing algorithms of Orthogonal Matching Pursuit (OMP), Homotopy technique, and Dichotomous coordinate descent (DCD) are presented. The simulation results demonstrate excellent performance with the compressive sensing methods.
{"title":"Multiple source localization for partial discharge monitoring in electrical substation","authors":"Y. Zhang, D. Upton, A. Jaber, H. Ahmed, U. Khan, B. Saeed, P. Mather, P. Lazaridis, R. Atkinson, M. F. Vieira, I. Glover","doi":"10.1109/LAPC.2015.7366001","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366001","url":null,"abstract":"This paper studies novel localization methods of multiple partial discharge sources in electrical substations. The three compressive sensing algorithms of Orthogonal Matching Pursuit (OMP), Homotopy technique, and Dichotomous coordinate descent (DCD) are presented. The simulation results demonstrate excellent performance with the compressive sensing methods.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127255822","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 : 2015-11-02DOI: 10.1109/LAPC.2015.7366033
I. Petropoulos, J. Sombrin, N. Delhote, C. Menudier
Two low cost stacked patch antennas designs operating at the Wi-Fi 2.4GHz frequency band for remotely piloted aircraft applications are presented in this study. The one is a stacked circular patch antenna with notches presenting 7dB gain, 380MHz bandwidth and circular polarization, while the second one is a stacked 4 element linear patch array with 14.2dB gain and 260MHz bandwidth, capable of beam-forming, appropriate for large distances. The array is integrated to a 1:4 Wilkinson power divider used as feeding network operating also in 2.4GHz frequency band, providing 370MHz bandwidth.
{"title":"Stacked patch antennas appropriate for remotely piloted aircraft applications","authors":"I. Petropoulos, J. Sombrin, N. Delhote, C. Menudier","doi":"10.1109/LAPC.2015.7366033","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366033","url":null,"abstract":"Two low cost stacked patch antennas designs operating at the Wi-Fi 2.4GHz frequency band for remotely piloted aircraft applications are presented in this study. The one is a stacked circular patch antenna with notches presenting 7dB gain, 380MHz bandwidth and circular polarization, while the second one is a stacked 4 element linear patch array with 14.2dB gain and 260MHz bandwidth, capable of beam-forming, appropriate for large distances. The array is integrated to a 1:4 Wilkinson power divider used as feeding network operating also in 2.4GHz frequency band, providing 370MHz bandwidth.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122631816","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 : 2015-11-02DOI: 10.1109/LAPC.2015.7366103
I. Rouissi, I. Ben Trad, J. Floc'h, H. Rmili, H. Trabelsi
A frequency reconfigurable multiband antenna using lumped capacitors has been designed and characterized. By embedding a pair of capacitors in the two opposite corners, the proposed patch can easily generate and control two resonant frequencies besides the main resonant frequency of the reference structure at F1=2.45GHz. When varying capacitance values from 0.845 to 3.454pF, tuning ranges of 990MHz (for the frequency F2) and 670MHz (for the frequency F3) can be achieved. Prototypes were realized and characterized. Simulated and measured results are presented and discussed.
{"title":"Design of frequency reconfigurable triband antenna using capacitive loading for wireless communications","authors":"I. Rouissi, I. Ben Trad, J. Floc'h, H. Rmili, H. Trabelsi","doi":"10.1109/LAPC.2015.7366103","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366103","url":null,"abstract":"A frequency reconfigurable multiband antenna using lumped capacitors has been designed and characterized. By embedding a pair of capacitors in the two opposite corners, the proposed patch can easily generate and control two resonant frequencies besides the main resonant frequency of the reference structure at F1=2.45GHz. When varying capacitance values from 0.845 to 3.454pF, tuning ranges of 990MHz (for the frequency F2) and 670MHz (for the frequency F3) can be achieved. Prototypes were realized and characterized. Simulated and measured results are presented and discussed.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126412222","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 : 2015-11-02DOI: 10.1109/LAPC.2015.7366058
E. Iorkyase, C. Tachtatzis, R. Atkinson, I. Glover
Partial discharge (PD) is a well-known indicator of the failure of insulators in electrical plant. Operators are pushing toward lower operating cost and higher reliability and this stimulates a demand for a diagnostic system capable of accurately locating PD sources especially in ageing electricity substations. Existing techniques used for PD source localisation can be prohibitively expensive. In this paper, a cost-effective radio fingerprinting technique is proposed. This technique uses the Received Signal Strength (RSS) extracted from PD measurements gathered using RF sensors. The proposed technique models the complex spatial characteristics of the radio environment, and uses this model for accurate PD localisation. Two models were developed and compared: k-nearest neighbour and a feed-forward neural network which uses regression as a form of function approximation. The results demonstrate that the neural network produced superior performance as a result of its robustness against noise.
{"title":"Localisation of partial discharge sources using radio fingerprinting technique","authors":"E. Iorkyase, C. Tachtatzis, R. Atkinson, I. Glover","doi":"10.1109/LAPC.2015.7366058","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366058","url":null,"abstract":"Partial discharge (PD) is a well-known indicator of the failure of insulators in electrical plant. Operators are pushing toward lower operating cost and higher reliability and this stimulates a demand for a diagnostic system capable of accurately locating PD sources especially in ageing electricity substations. Existing techniques used for PD source localisation can be prohibitively expensive. In this paper, a cost-effective radio fingerprinting technique is proposed. This technique uses the Received Signal Strength (RSS) extracted from PD measurements gathered using RF sensors. The proposed technique models the complex spatial characteristics of the radio environment, and uses this model for accurate PD localisation. Two models were developed and compared: k-nearest neighbour and a feed-forward neural network which uses regression as a form of function approximation. The results demonstrate that the neural network produced superior performance as a result of its robustness against noise.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115145447","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 : 2015-11-02DOI: 10.1109/LAPC.2015.7366122
A. Haskou, S. Collardey, A. Sharaiha
In this paper, we present a compact broadside superdirective antenna array based on a planar parasitic superdirective unit-element. The array is designed for 905MHz frequency band, its dimensions are 200 × 54 × 24mm3 (0.6λ × 0.16λ × 0.07λ), and it presents a directivity of 9.2dBi and radiation efficiency of 8.3%. Integrating the initial parasitic array in a PCB of 110 × 70mm2, the array total dimensions are 200 × 110 × 70mm3(0.58λ × 0.32λ × 0.2λ), and it presents a directivity of 9.8dBi and radiation efficiency of 64%.
{"title":"Small 3D array design using superdirective antennas","authors":"A. Haskou, S. Collardey, A. Sharaiha","doi":"10.1109/LAPC.2015.7366122","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366122","url":null,"abstract":"In this paper, we present a compact broadside superdirective antenna array based on a planar parasitic superdirective unit-element. The array is designed for 905MHz frequency band, its dimensions are 200 × 54 × 24mm3 (0.6λ × 0.16λ × 0.07λ), and it presents a directivity of 9.2dBi and radiation efficiency of 8.3%. Integrating the initial parasitic array in a PCB of 110 × 70mm2, the array total dimensions are 200 × 110 × 70mm3(0.58λ × 0.32λ × 0.2λ), and it presents a directivity of 9.8dBi and radiation efficiency of 64%.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117200923","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366125
Selvakumar Ulaganathan, S. Koziel, A. Bekasiewicz, I. Couckuyt, E. Laermans, T. Dhaene
Reliable yet fast surrogate models are indispensable in the design of contemporary antenna structures. Data-driven models, e.g., based on Gaussian Processes or support-vector regression, offer sufficient flexibility and speed, however, their setup cost is large and grows very quickly with the dimensionality of the design space. In this paper, we propose cost-efficient modeling of antenna structures using Gradient-Enhanced Kriging. In our approach, the training data set contains, apart from the EM-simulation responses of the structure at hand, also derivative data at the respective training locations obtained at little extra cost using adjoint sensitivity techniques. We demonstrate that introduction of the derivative information into the model allows for considerable reduction of the model setup cost (in terms of the number of training points required) without compromising its predictive power. The Gradient-Enhanced Kriging technique is illustrated using a dielectric resonator antenna structure. Comparison with conventional Kriging interpolation is also provided.
{"title":"Cost-efficient modeling of antenna structures using Gradient-Enhanced Kriging","authors":"Selvakumar Ulaganathan, S. Koziel, A. Bekasiewicz, I. Couckuyt, E. Laermans, T. Dhaene","doi":"10.1109/LAPC.2015.7366125","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366125","url":null,"abstract":"Reliable yet fast surrogate models are indispensable in the design of contemporary antenna structures. Data-driven models, e.g., based on Gaussian Processes or support-vector regression, offer sufficient flexibility and speed, however, their setup cost is large and grows very quickly with the dimensionality of the design space. In this paper, we propose cost-efficient modeling of antenna structures using Gradient-Enhanced Kriging. In our approach, the training data set contains, apart from the EM-simulation responses of the structure at hand, also derivative data at the respective training locations obtained at little extra cost using adjoint sensitivity techniques. We demonstrate that introduction of the derivative information into the model allows for considerable reduction of the model setup cost (in terms of the number of training points required) without compromising its predictive power. The Gradient-Enhanced Kriging technique is illustrated using a dielectric resonator antenna structure. Comparison with conventional Kriging interpolation is also provided.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115761775","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366019
P. Theofanopoulos, C. Lavranos, K. Zoiros, G. Granet, P. Gkonis, J. Sahalos, G. Kyriacou
A two dimensional Finite Difference Frequency Domain (2D-FDFD) eigenanalysis of an array consisting of periodically located strips printed on axially magnetized ferrite film is presented. The main interest in these structures arises from our previous study which revealed their support of backward surface and possibly backward leaky waves. Moreover these structures exhibit non-reciprocal phenomena. These phenomena are studied thoroughly by using our two - dimensional curvilinear frequency domain finite difference (2D-FDFD) method, modified appropriately for the eigenanalysis of periodic structures. The present effort is particularly focused on the study of the non-reciprocal phenomena involved in periodic structures loaded with magnetized ferrites.
{"title":"FDFD eigenanalysis of non-reciprocal periodic structures","authors":"P. Theofanopoulos, C. Lavranos, K. Zoiros, G. Granet, P. Gkonis, J. Sahalos, G. Kyriacou","doi":"10.1109/LAPC.2015.7366019","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366019","url":null,"abstract":"A two dimensional Finite Difference Frequency Domain (2D-FDFD) eigenanalysis of an array consisting of periodically located strips printed on axially magnetized ferrite film is presented. The main interest in these structures arises from our previous study which revealed their support of backward surface and possibly backward leaky waves. Moreover these structures exhibit non-reciprocal phenomena. These phenomena are studied thoroughly by using our two - dimensional curvilinear frequency domain finite difference (2D-FDFD) method, modified appropriately for the eigenanalysis of periodic structures. The present effort is particularly focused on the study of the non-reciprocal phenomena involved in periodic structures loaded with magnetized ferrites.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125184995","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366067
S. Koziel, A. Bekasiewicz
In this work, a technique for fast multi-objective design optimization of antenna structures is presented. In our approach, the initial approximation of the Pareto set representing the best possible trade-offs between conflicting design objectives is obtained by means of sequential patching of the design space. The latter is a stencil-based search that aims at creating a path that connects the extreme Pareto-optimal designs (obtained by means of single-objective optimization runs). For the sake of computational efficiency, the patching process is realized at the level of coarse-discretization EM simulation model. The final Pareto front is obtained through surrogate-based optimization, and it is reusing the EM simulation data acquired at the initial design stage. The proposed approach is demonstrated using the example of an ultrawideband monopole antenna.
{"title":"Fast multi-objective antenna optimization using sequential patching and variable-fidelity EM models","authors":"S. Koziel, A. Bekasiewicz","doi":"10.1109/LAPC.2015.7366067","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366067","url":null,"abstract":"In this work, a technique for fast multi-objective design optimization of antenna structures is presented. In our approach, the initial approximation of the Pareto set representing the best possible trade-offs between conflicting design objectives is obtained by means of sequential patching of the design space. The latter is a stencil-based search that aims at creating a path that connects the extreme Pareto-optimal designs (obtained by means of single-objective optimization runs). For the sake of computational efficiency, the patching process is realized at the level of coarse-discretization EM simulation model. The final Pareto front is obtained through surrogate-based optimization, and it is reusing the EM simulation data acquired at the initial design stage. The proposed approach is demonstrated using the example of an ultrawideband monopole antenna.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125273939","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366036
M. Yousefi, H. Aliakbarian, R. Sadeghzadeh
RF and microwave filters are an undeniable part of electronic and telecommunication systems and are widely used in receivers, tuners, up/down converters, etc. In this paper, the design procedure and results of an 11-order hairpin band pass filter, with Cauer-Chebyshev response designed at C band is presented. The filter is integrated with a harmonic suppression circuit based on quarter-wavelength short stubs. The short stubs demonstrate a good quality short circuit at harmonic frequencies. Also, because of quarter-wavelength transformer, it present open circuit at passband frequencies and had no significant impact with it. The total circuit has about 1 GHz 3dB-bandwidth at the center frequency of 4.15 GHz (3.65 GHz to 4.65 GHz) which is an ultra wide band for hairpin filters. The return loss of better than -12.3 dB and the insertion loss of 2.2 dB in pass-band are achieved. Also the rejection of filter at 5 GHz is -59.5 dB demonstrating that the stopband response of the filter is excellent. Finally with regard to short-stubs, the harmonic spurious suppression of more than 40 dB is achieved to suppress undesirable frequencies.
{"title":"Design and integration of a high-order hairpin bandpass filter with a spurious suppression circuit","authors":"M. Yousefi, H. Aliakbarian, R. Sadeghzadeh","doi":"10.1109/LAPC.2015.7366036","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366036","url":null,"abstract":"RF and microwave filters are an undeniable part of electronic and telecommunication systems and are widely used in receivers, tuners, up/down converters, etc. In this paper, the design procedure and results of an 11-order hairpin band pass filter, with Cauer-Chebyshev response designed at C band is presented. The filter is integrated with a harmonic suppression circuit based on quarter-wavelength short stubs. The short stubs demonstrate a good quality short circuit at harmonic frequencies. Also, because of quarter-wavelength transformer, it present open circuit at passband frequencies and had no significant impact with it. The total circuit has about 1 GHz 3dB-bandwidth at the center frequency of 4.15 GHz (3.65 GHz to 4.65 GHz) which is an ultra wide band for hairpin filters. The return loss of better than -12.3 dB and the insertion loss of 2.2 dB in pass-band are achieved. Also the rejection of filter at 5 GHz is -59.5 dB demonstrating that the stopband response of the filter is excellent. Finally with regard to short-stubs, the harmonic spurious suppression of more than 40 dB is achieved to suppress undesirable frequencies.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125676229","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 : 2015-11-01DOI: 10.1109/LAPC.2015.7366143
I. Morrow, K. Morrison, M. Finnis, W. Whittow
This paper presents the design of a low profile retrodirective surface composed of a frequency selective surface (FSS). The principle of operation of re-radiation and scattering from the array surface is outlined. A full-wave analysis of individual FSS unit cells and the assembled reflect array is performed to better understand and design the reflector. A commensurate array of unit cells with progressive phase shift is realised using non-identical dimension dual resonant circular loop FSSs. A prototype reflect array was manufactured and the monostatic backscattered field measured in horizontal and vertical polarisation. Comparative measurements on similar sized flat plate and dihedral reflector surfaces were made that demonstrate the reflect array performance.
{"title":"A low profile retrodirective frequency selective surface for radar earth observation","authors":"I. Morrow, K. Morrison, M. Finnis, W. Whittow","doi":"10.1109/LAPC.2015.7366143","DOIUrl":"https://doi.org/10.1109/LAPC.2015.7366143","url":null,"abstract":"This paper presents the design of a low profile retrodirective surface composed of a frequency selective surface (FSS). The principle of operation of re-radiation and scattering from the array surface is outlined. A full-wave analysis of individual FSS unit cells and the assembled reflect array is performed to better understand and design the reflector. A commensurate array of unit cells with progressive phase shift is realised using non-identical dimension dual resonant circular loop FSSs. A prototype reflect array was manufactured and the monostatic backscattered field measured in horizontal and vertical polarisation. Comparative measurements on similar sized flat plate and dihedral reflector surfaces were made that demonstrate the reflect array performance.","PeriodicalId":339610,"journal":{"name":"2015 Loughborough Antennas & Propagation Conference (LAPC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115099604","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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