Pub Date : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637212
M. Lyalinov, N. Zhu
In the present work we study the diffraction of the electromagnetic field from dipole located over an impedance wedge. We give the asymptotic expressions of the reflected waves from the wedge's faces, of the diffracted wave from the edge as well as those of the surface waves along the impedance faces. It is assumed that the source is not located in a close vicinity of the wedge's faces.
{"title":"The diffraction of a dipole-field by an impedance wedge","authors":"M. Lyalinov, N. Zhu","doi":"10.1109/URSI-EMTS.2010.5637212","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637212","url":null,"abstract":"In the present work we study the diffraction of the electromagnetic field from dipole located over an impedance wedge. We give the asymptotic expressions of the reflected waves from the wedge's faces, of the diffracted wave from the edge as well as those of the surface waves along the impedance faces. It is assumed that the source is not located in a close vicinity of the wedge's faces.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127837497","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637337
L. Reichardt, T. Schipper, T. Zwick
Future mobile communications, in the mean of Car-to-Car (C2C), Car-to-Infrastructure (C2I) or Vehicle-to-Vehicle (V2V) communication, will make use of multiple antenna systems like diversity or MIMO. Especially in multiple antenna systems finding the optimal antenna configuration in order to ensure the best performance is a very difficult task. Presently antennas in mobile communications systems, especially in cars, are selected in a rather expensive and time consuming test-drives, if at all. This will not be technically possible and affordable for multiple antenna systems in the future. Here a solution for this problem is demonstrated defined as Virtual Drive. In the Virtual Drive the quality of the antenna system is determined by simulating the mobile, driving through the EM-fields radiated from the transmitter. The multi-path propagation from the transmitter is calculated by a 3D ray-tracing tool, which is based on the theory of geometrical optics (GO) and the Uniform Theory of Diffraction (UTD). The combination of both yields a “virtual drive” through any scenario and allows optimization of antenna configurations without extensive measurement campaigns and without prototyping all configurations to be investigated. Additionally Virtual Drive provides a perfect repeatability of the testing environment.
{"title":"“Virtual Drive” physical layer simulations for Vehicle-to-Vehicle communication","authors":"L. Reichardt, T. Schipper, T. Zwick","doi":"10.1109/URSI-EMTS.2010.5637337","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637337","url":null,"abstract":"Future mobile communications, in the mean of Car-to-Car (C2C), Car-to-Infrastructure (C2I) or Vehicle-to-Vehicle (V2V) communication, will make use of multiple antenna systems like diversity or MIMO. Especially in multiple antenna systems finding the optimal antenna configuration in order to ensure the best performance is a very difficult task. Presently antennas in mobile communications systems, especially in cars, are selected in a rather expensive and time consuming test-drives, if at all. This will not be technically possible and affordable for multiple antenna systems in the future. Here a solution for this problem is demonstrated defined as Virtual Drive. In the Virtual Drive the quality of the antenna system is determined by simulating the mobile, driving through the EM-fields radiated from the transmitter. The multi-path propagation from the transmitter is calculated by a 3D ray-tracing tool, which is based on the theory of geometrical optics (GO) and the Uniform Theory of Diffraction (UTD). The combination of both yields a “virtual drive” through any scenario and allows optimization of antenna configurations without extensive measurement campaigns and without prototyping all configurations to be investigated. Additionally Virtual Drive provides a perfect repeatability of the testing environment.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"202 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133794341","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637038
M. Ravan, R. Amineh, N. Nikolova
A new two-dimensional (2D) microwave holographic technique is proposed to reconstruct the 2D image of a target. It is based on the data recorded by two antennas scanning two rectangular parallel apertures on both sides of a target. In this method the reflection coefficients of the antennas are first processed to localize target in the range direction. Then, the 2D image of the target is reconstructed. There is no assumption for the incident field and both the back-scattered and forward-scattered signals can be used to reconstruct the image of the target. This makes the technique applicable to tomographic measurements where the near-field signal transmitted through the target is measured.
{"title":"Near-field microwave holographic imaging: Target localization and resolution study","authors":"M. Ravan, R. Amineh, N. Nikolova","doi":"10.1109/URSI-EMTS.2010.5637038","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637038","url":null,"abstract":"A new two-dimensional (2D) microwave holographic technique is proposed to reconstruct the 2D image of a target. It is based on the data recorded by two antennas scanning two rectangular parallel apertures on both sides of a target. In this method the reflection coefficients of the antennas are first processed to localize target in the range direction. Then, the 2D image of the target is reconstructed. There is no assumption for the incident field and both the back-scattered and forward-scattered signals can be used to reconstruct the image of the target. This makes the technique applicable to tomographic measurements where the near-field signal transmitted through the target is measured.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122223595","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637227
S. Rengarajan
We present a perturbation technique for improving the design parameters of a waveguide-fed planar slot array consisting of longitudinal radiating slots and centered-inclined coupling slots. Initial design is performed using the well-known Elliott technique. Subsequently a method-of-moments solution to the pertinent coupled integral equations of the aperture electric field of all slots in the array is employed to perturb the slot parameters. This process improves the slot aperture distribution and the return loss.
{"title":"A perturbation technique for improving the design of a planar slot array","authors":"S. Rengarajan","doi":"10.1109/URSI-EMTS.2010.5637227","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637227","url":null,"abstract":"We present a perturbation technique for improving the design parameters of a waveguide-fed planar slot array consisting of longitudinal radiating slots and centered-inclined coupling slots. Initial design is performed using the well-known Elliott technique. Subsequently a method-of-moments solution to the pertinent coupled integral equations of the aperture electric field of all slots in the array is employed to perturb the slot parameters. This process improves the slot aperture distribution and the return loss.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131026966","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637287
Chih-Yu Wang, Shih-yung Chung, C. Teng, Chung-Ping Chen, Hung-chun Chang
A pseudospectral frequency-domain (PSFD) method with multi-domain approach and based on Legendre polynomials is developed for solving Maxwell's equations. One aim of the proposed method is to more accurately model problems in plasmonics in which electromagnetic waves interact with metallic structures at optical frequencies. Calculation of light scattering by a silver circular cylinder demonstrates that the accuracy of the obtained field strength can be as good as on the order of 10−9 of the incident field strength.
{"title":"A legendre pseudospectral frequency-domain method for solving Maxwell's equations","authors":"Chih-Yu Wang, Shih-yung Chung, C. Teng, Chung-Ping Chen, Hung-chun Chang","doi":"10.1109/URSI-EMTS.2010.5637287","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637287","url":null,"abstract":"A pseudospectral frequency-domain (PSFD) method with multi-domain approach and based on Legendre polynomials is developed for solving Maxwell's equations. One aim of the proposed method is to more accurately model problems in plasmonics in which electromagnetic waves interact with metallic structures at optical frequencies. Calculation of light scattering by a silver circular cylinder demonstrates that the accuracy of the obtained field strength can be as good as on the order of 10−9 of the incident field strength.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128417384","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637174
A. Hirata, K. Sugiura, Y. Kanai, O. Fujiwara
The present study investigates the correlation between maximum temperature elevation and peak mass-averaged specific absorption rates (SARs) in layered one-dimensional model and layered cubical model. The resolution of the model is 0.5 mm or less in order to calculate the correlation in frequencies up to 10 GHz. Our computational investigation in the one-dimensional model showed that the variability due to the thickness is several dozen percents or more, which is dependent on the frequency. In the three-dimensional homogeneous model, SARs averaged over 10 g provides reasonable correlation with maximum temperature elevation for frequencies up to 6 GHz. For the layered cubical model, the SAR averaged over 1g provides better frequency characteristics of the correlation with the maximum temperature elevation, while the variability of the ratio for different tissue thickness remains future work.
{"title":"Correlation between peak spatial-average SAR and maximum temperature elevation in layered cubical model in the frequency range above 3 GHz","authors":"A. Hirata, K. Sugiura, Y. Kanai, O. Fujiwara","doi":"10.1109/URSI-EMTS.2010.5637174","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637174","url":null,"abstract":"The present study investigates the correlation between maximum temperature elevation and peak mass-averaged specific absorption rates (SARs) in layered one-dimensional model and layered cubical model. The resolution of the model is 0.5 mm or less in order to calculate the correlation in frequencies up to 10 GHz. Our computational investigation in the one-dimensional model showed that the variability due to the thickness is several dozen percents or more, which is dependent on the frequency. In the three-dimensional homogeneous model, SARs averaged over 10 g provides reasonable correlation with maximum temperature elevation for frequencies up to 6 GHz. For the layered cubical model, the SAR averaged over 1g provides better frequency characteristics of the correlation with the maximum temperature elevation, while the variability of the ratio for different tissue thickness remains future work.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134084676","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637011
V. Timchenko, E. Heyman, A. Boag
We present a software package INDOOR-GBS (Gaussian Beam Summation) designed to simulate indoor electro-magnetic field propagation in the ultra wideband (UWB) regime. The package is based on the GBS method where the field of the transmitting antenna is expanded into a superposition of GBs that emerge from the source in a discrete set of directions. Thereafter the beams are traced in the configuration through multiple reflections and transmissions at the walls/ceilings/floors and the field is calculated by summing the contributions of the beams that pass near the zone of interest. The algorithm consists mainly of two phases: a processing phase where the beams are traced through the medium, and a post-processing phase where the field and the channel parameters are calculated for the given source and receiver antennas. The processing phase utilizes a dyadic electromagnetic formulation so that the antennas' properties are used only in the post-processing phase, thus facilitating efficient post-processing calculations for antenna and channel optimization. The algorithm also employs a particular set of isodiffracting GBs (ID-GB), whose propagation characteristics are frequency independent and lead to efficient UWB calculations.
{"title":"Gaussian beam summation algorithm for ultra wide band indoor channel characterization","authors":"V. Timchenko, E. Heyman, A. Boag","doi":"10.1109/URSI-EMTS.2010.5637011","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637011","url":null,"abstract":"We present a software package INDOOR-GBS (Gaussian Beam Summation) designed to simulate indoor electro-magnetic field propagation in the ultra wideband (UWB) regime. The package is based on the GBS method where the field of the transmitting antenna is expanded into a superposition of GBs that emerge from the source in a discrete set of directions. Thereafter the beams are traced in the configuration through multiple reflections and transmissions at the walls/ceilings/floors and the field is calculated by summing the contributions of the beams that pass near the zone of interest. The algorithm consists mainly of two phases: a processing phase where the beams are traced through the medium, and a post-processing phase where the field and the channel parameters are calculated for the given source and receiver antennas. The processing phase utilizes a dyadic electromagnetic formulation so that the antennas' properties are used only in the post-processing phase, thus facilitating efficient post-processing calculations for antenna and channel optimization. The algorithm also employs a particular set of isodiffracting GBs (ID-GB), whose propagation characteristics are frequency independent and lead to efficient UWB calculations.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133215259","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637035
S. Kidera, T. Sakamoto, Toru Sato
Near field radar employing UWB (Ultra Wideband) signals with its high range resolution is promising as various sensing applications. It enables robotic or security sensors that can identify a human body in invisible situations. As one of the most promising radar algorithms, the RPM (Range Points Migration) is proposed. This offers an accurate 3-D (3-dimensional) surface extraction for various target shape. However, in the case of a complicated target surface whose variation scale is less than wavelength, it still suffers from image distortion caused by multiple interference signals with different waveforms. As a substantial solution, this paper proposes a novel range extraction algorithm by extending the Capon, known as frequency domain interferometry (FDI). This algorithm combines reference signal optimization with the original Capon to enhance the accuracy and resolution for an observed range into which a deformed waveform model is introduced. The results obtained from numerical simulations and an experiment prove that super-resolution UWB radar imaging is achieved by the proposed method, even for an extremely complex-surface target, including edges.
{"title":"Experimental study on super-resolution 3-D imaging algorithm based on extended capon with reference signal optimization for UWB radars","authors":"S. Kidera, T. Sakamoto, Toru Sato","doi":"10.1109/URSI-EMTS.2010.5637035","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637035","url":null,"abstract":"Near field radar employing UWB (Ultra Wideband) signals with its high range resolution is promising as various sensing applications. It enables robotic or security sensors that can identify a human body in invisible situations. As one of the most promising radar algorithms, the RPM (Range Points Migration) is proposed. This offers an accurate 3-D (3-dimensional) surface extraction for various target shape. However, in the case of a complicated target surface whose variation scale is less than wavelength, it still suffers from image distortion caused by multiple interference signals with different waveforms. As a substantial solution, this paper proposes a novel range extraction algorithm by extending the Capon, known as frequency domain interferometry (FDI). This algorithm combines reference signal optimization with the original Capon to enhance the accuracy and resolution for an observed range into which a deformed waveform model is introduced. The results obtained from numerical simulations and an experiment prove that super-resolution UWB radar imaging is achieved by the proposed method, even for an extremely complex-surface target, including edges.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133146597","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637137
P. M. van den Berg, A. Abubakar
Optical Imaging of the permittivity profile from optical diffraction tomography data is discussed. In order to arrive at sub-100 nm resolution it is necessary to employ nonlinear inversion methods that yield quantitative information of the permittivity distribution. Therefore, the so-called multiplicative regularized contrast source inversion (MR-CSI) method is adopted to solve the problem at hand. For a two-dimensional representative example, it is demonstrated that, using a wavelength of 400 nm, resolutions of the order of 20 to 30 nm can be achieved.
{"title":"Digital optical microscopy using the MR-CSI method","authors":"P. M. van den Berg, A. Abubakar","doi":"10.1109/URSI-EMTS.2010.5637137","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637137","url":null,"abstract":"Optical Imaging of the permittivity profile from optical diffraction tomography data is discussed. In order to arrive at sub-100 nm resolution it is necessary to employ nonlinear inversion methods that yield quantitative information of the permittivity distribution. Therefore, the so-called multiplicative regularized contrast source inversion (MR-CSI) method is adopted to solve the problem at hand. For a two-dimensional representative example, it is demonstrated that, using a wavelength of 400 nm, resolutions of the order of 20 to 30 nm can be achieved.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115786454","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 : 2010-11-15DOI: 10.1109/URSI-EMTS.2010.5637272
M. Furqan, L. Vietzorreck
In this contribution new developments in the Methods of Lines (MoL) are shown, which make the method to a competitive tool for the analysis of cascaded structures with repetitive sections. The MoL is very well suited for the analysis of layered or cascaded elements, as it uses only a two-dimensional discretization, within the layers or sections analytic calculation is used. Nevertheless, due to the required eigenmode analysis the needed computation time needed is still high compared to commercial tools. Several approaches have been developed in order to make the MoL more efficient, here some of these features have been combined to a new algorithm. First Floquet`s theorem is efficiently used to analyze structures with repeating sections without significant increase in computation time. The number of employed modes is reduced by applying the principle of localized and accessible modes. Last an additional but fast 2D analysis is used to increase the accuracy in determining the loss of lossy conductors. A comparison is made for a distributed MEMS transmission line (DMTL) with up to 20 sections, comparing the results of the new MoL algorithm with commercial tools.
{"title":"New modelling aspects in the Method of Lines","authors":"M. Furqan, L. Vietzorreck","doi":"10.1109/URSI-EMTS.2010.5637272","DOIUrl":"https://doi.org/10.1109/URSI-EMTS.2010.5637272","url":null,"abstract":"In this contribution new developments in the Methods of Lines (MoL) are shown, which make the method to a competitive tool for the analysis of cascaded structures with repetitive sections. The MoL is very well suited for the analysis of layered or cascaded elements, as it uses only a two-dimensional discretization, within the layers or sections analytic calculation is used. Nevertheless, due to the required eigenmode analysis the needed computation time needed is still high compared to commercial tools. Several approaches have been developed in order to make the MoL more efficient, here some of these features have been combined to a new algorithm. First Floquet`s theorem is efficiently used to analyze structures with repeating sections without significant increase in computation time. The number of employed modes is reduced by applying the principle of localized and accessible modes. Last an additional but fast 2D analysis is used to increase the accuracy in determining the loss of lossy conductors. A comparison is made for a distributed MEMS transmission line (DMTL) with up to 20 sections, comparing the results of the new MoL algorithm with commercial tools.","PeriodicalId":404116,"journal":{"name":"2010 URSI International Symposium on Electromagnetic Theory","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115977981","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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