Chan Wang, Chao Qian, Hao Hu, Lian Shen, Zuojia Wang, Huaping Wang, Zhiwei Xu, Baile Zhang, Hongsheng Chen, Xiao Lin
Enhancing the scattering of light from subwavelength structures is of both fundamental and practical significance. While the scattering cross section from each channel cannot exceed the single-channel limit, it is recently reported that the total cross section can far exceed this limit if one overlaps the contribution from many channels. Such a phenomenon about enhancing the scattering from subwavelength structures in free space is denoted as the superscattering in some literature. However, the scatterer in practical scenarios is not always in free space but may be embedded in environments with non-unity refractive index n. The influence of environments on the superscattering remains elusive. Here the superscattering from subwavelength structures in the isotropic environment with near-zero index are theoretically investigated. Importantly, a smaller n can lead to a larger total cross section for superscattering. The underlying mechanism is that a smaller n can give rise to a larger singlechannel limit. Our work thus indicates that the scattering from subwavelength structures can be further enhanced if one simultaneously maximizes the single-channel limit and the contribution from many channels.
{"title":"SUPERSCATTERING OF LIGHT IN REFRACTIVE-INDEX NEAR-ZERO ENVIRONMENTS","authors":"Chan Wang, Chao Qian, Hao Hu, Lian Shen, Zuojia Wang, Huaping Wang, Zhiwei Xu, Baile Zhang, Hongsheng Chen, Xiao Lin","doi":"10.2528/pier20070401","DOIUrl":"https://doi.org/10.2528/pier20070401","url":null,"abstract":"Enhancing the scattering of light from subwavelength structures is of both fundamental and practical significance. While the scattering cross section from each channel cannot exceed the single-channel limit, it is recently reported that the total cross section can far exceed this limit if one overlaps the contribution from many channels. Such a phenomenon about enhancing the scattering from subwavelength structures in free space is denoted as the superscattering in some literature. However, the scatterer in practical scenarios is not always in free space but may be embedded in environments with non-unity refractive index n. The influence of environments on the superscattering remains elusive. Here the superscattering from subwavelength structures in the isotropic environment with near-zero index are theoretically investigated. Importantly, a smaller n can lead to a larger total cross section for superscattering. The underlying mechanism is that a smaller n can give rise to a larger singlechannel limit. Our work thus indicates that the scattering from subwavelength structures can be further enhanced if one simultaneously maximizes the single-channel limit and the contribution from many channels.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"37 1","pages":"15-23"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74072149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Zhang, Panpan Wang, Shuai Zhang, Long Li, Ping Li, W. Sha, L. J. Jiang
Electromagnetic-circuital-thermal multiphysics simulation is a very important topic in the field of integrated circuits (ICs), microwave circuits, antennas, etc. This paper presents a comprehensive review of the state of the art of electromagnetic-circuital-thermal multiphysics simulation method. Most efforts were focused on electromagnetic-circuital co-simulation and electromagnetic-thermal cosimulation. A brief introduction of related theories like governing equations, numerical methods, and coupling mechanisms is also included.
{"title":"ELECTROMAGNETIC-CIRCUITAL-THERMAL MULTIPHYSICS SIMULATION METHOD: A REVIEW (INVITED)","authors":"H. Zhang, Panpan Wang, Shuai Zhang, Long Li, Ping Li, W. Sha, L. J. Jiang","doi":"10.2528/pier20112801","DOIUrl":"https://doi.org/10.2528/pier20112801","url":null,"abstract":"Electromagnetic-circuital-thermal multiphysics simulation is a very important topic in the field of integrated circuits (ICs), microwave circuits, antennas, etc. This paper presents a comprehensive review of the state of the art of electromagnetic-circuital-thermal multiphysics simulation method. Most efforts were focused on electromagnetic-circuital co-simulation and electromagnetic-thermal cosimulation. A brief introduction of related theories like governing equations, numerical methods, and coupling mechanisms is also included.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"26 1","pages":"87-101"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87950027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Varshney, Rakesh Singh, V. Pandey, R. Yaduvanshi
A two port multi-input-multi-output (MIMO) dielectric resonator (DR) antenna (DRA) is proposed with circularly polarized radiation. The antenna geometry allows to find circular polarization and improved impedance bandwidth by reducing the separation between the DR elements. The isolation between the ports of the antenna remains more than 15 dB in the operating passband even after reducing the separation between the radiating elements. The antenna provides the 10-dB impedance and 3-dB axial ratio bandwidth of 34.85% and 4.55%, respectively. The MIMO performance of the proposed antenna is confirmed by calculating the parameters like envelop correlation coefficient, diversity gain, mean effective gain, channel capacity loss, and the total active reflection coefficient. The proposed antenna can be utilized for C-band applications.
{"title":"CIRCULARLY POLARIZED TWO-PORT MIMO DIELECTRIC RESONATOR ANTENNA","authors":"G. Varshney, Rakesh Singh, V. Pandey, R. Yaduvanshi","doi":"10.2528/pierm20011003","DOIUrl":"https://doi.org/10.2528/pierm20011003","url":null,"abstract":"A two port multi-input-multi-output (MIMO) dielectric resonator (DR) antenna (DRA) is proposed with circularly polarized radiation. The antenna geometry allows to find circular polarization and improved impedance bandwidth by reducing the separation between the DR elements. The isolation between the ports of the antenna remains more than 15 dB in the operating passband even after reducing the separation between the radiating elements. The antenna provides the 10-dB impedance and 3-dB axial ratio bandwidth of 34.85% and 4.55%, respectively. The MIMO performance of the proposed antenna is confirmed by calculating the parameters like envelop correlation coefficient, diversity gain, mean effective gain, channel capacity loss, and the total active reflection coefficient. The proposed antenna can be utilized for C-band applications.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"56 1","pages":"19-28"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81048983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we present the design and fabrication of a sectoral beam slotted antenna in substrate integrated waveguide (SIW) technology able to achieve a high roll-off sectoral pattern in the horizontal plane and a very narrow beam in the vertical plane, as required in surveillance applications in the band 76–77 GHz. The proposed antenna is designed and fabricated in multi-layer PCB technology, which allows to integrate both the corporate feeding network and the radiating aperture in the same planar and lightweight device. To achieve a remarkable roll-off (> 5.5 dB/deg) and a reduced ripple (< 1.5 dB), the antenna has been designed by synthesizing a sinc-shaped (uniform) aperture distribution along x-direction (y-direction). The synthesis and optimization of so tapered aperture distributions is not easy to be found in the literature, especially for planar devices. A prototype of such an antenna has been fabricated with a horizontal half-power beamwidth (HPBW) of 30◦, by embedding both the feeding network and the radiating aperture in three stacked dielectric substrates. Measurements of the prototype show a fair agreement with numerical simulations.
{"title":"DESIGN AND FABRICATION OF A SECTORAL BEAM SLOTTED ANTENNA IN SIW TECHNOLOGY FOR SURVEILLANCE APPLICATIONS AT MILLIMETER WAVES","authors":"S. C. Pavone, M. Albani","doi":"10.2528/pier20012102","DOIUrl":"https://doi.org/10.2528/pier20012102","url":null,"abstract":"In this paper, we present the design and fabrication of a sectoral beam slotted antenna in substrate integrated waveguide (SIW) technology able to achieve a high roll-off sectoral pattern in the horizontal plane and a very narrow beam in the vertical plane, as required in surveillance applications in the band 76–77 GHz. The proposed antenna is designed and fabricated in multi-layer PCB technology, which allows to integrate both the corporate feeding network and the radiating aperture in the same planar and lightweight device. To achieve a remarkable roll-off (> 5.5 dB/deg) and a reduced ripple (< 1.5 dB), the antenna has been designed by synthesizing a sinc-shaped (uniform) aperture distribution along x-direction (y-direction). The synthesis and optimization of so tapered aperture distributions is not easy to be found in the literature, especially for planar devices. A prototype of such an antenna has been fabricated with a horizontal half-power beamwidth (HPBW) of 30◦, by embedding both the feeding network and the radiating aperture in three stacked dielectric substrates. Measurements of the prototype show a fair agreement with numerical simulations.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"9 1","pages":"55-65"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79780196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents an overview and review of the fundamental implicit finite-difference time-domain (FDTD) schemes for computational electromagnetics (CEM) and educational mobile apps. The fundamental implicit FDTD schemes are unconditionally stable and feature the most concise update procedures with matrix-operator-free right-hand sides (RHS). We review the developments of fundamental implicit schemes, which are simpler and more efficient than all previous implicit schemes having RHS matrix operators. They constitute the basis of unification for many implicit schemes including classical ones, providing insights into their inter-relations along with simplifications, concise updates and efficient implementations. Based on the fundamental implicit schemes, further developments can be carried out more conveniently. Being the core CEM on mobile apps, the multiple one-dimensional (M1-D) FDTD methods are also reviewed. To simulate multiple transmission lines, stubs and coupled transmission lines efficiently, the M1-D explicit FDTD method as well as the unconditionally stable M1-D fundamental alternating direction implicit (FADI) FDTD and coupled line (CL) FDTD methods are discussed. With the unconditional stability of FADI methods, the simulations are fast-forwardable with enhanced efficiency. This is very useful for quick concept illustrations or phenomena demonstrations during interactive teaching and learning. Besides time domain, many frequency-domain methods are well-suited for further developments of useful mobile apps as well.
{"title":"FUNDAMENTAL IMPLICIT FDTD SCHEMES FOR COMPUTATIONAL ELECTROMAGNETICS AND EDUCATIONAL MOBILE APPS (INVITED REVIEW)","authors":"E. L. Tan","doi":"10.2528/pier20061002","DOIUrl":"https://doi.org/10.2528/pier20061002","url":null,"abstract":"This paper presents an overview and review of the fundamental implicit finite-difference time-domain (FDTD) schemes for computational electromagnetics (CEM) and educational mobile apps. The fundamental implicit FDTD schemes are unconditionally stable and feature the most concise update procedures with matrix-operator-free right-hand sides (RHS). We review the developments of fundamental implicit schemes, which are simpler and more efficient than all previous implicit schemes having RHS matrix operators. They constitute the basis of unification for many implicit schemes including classical ones, providing insights into their inter-relations along with simplifications, concise updates and efficient implementations. Based on the fundamental implicit schemes, further developments can be carried out more conveniently. Being the core CEM on mobile apps, the multiple one-dimensional (M1-D) FDTD methods are also reviewed. To simulate multiple transmission lines, stubs and coupled transmission lines efficiently, the M1-D explicit FDTD method as well as the unconditionally stable M1-D fundamental alternating direction implicit (FADI) FDTD and coupled line (CL) FDTD methods are discussed. With the unconditional stability of FADI methods, the simulations are fast-forwardable with enhanced efficiency. This is very useful for quick concept illustrations or phenomena demonstrations during interactive teaching and learning. Besides time domain, many frequency-domain methods are well-suited for further developments of useful mobile apps as well.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"26 1","pages":"39-59"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72861209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Tabatadze, K. Karaçuha, E. Veliyev, E. Karaçuha
In this article, the diffraction of plane electromagnetic waves by double half-planes with fractional boundary conditions is considered. As particular cases, the diffractions by wedges and corners are considered for different values of fractional orders. The results are compared to the analytical ones. The interesting properties of wedge diffraction are outlined for intermediate fractional orders.
{"title":"THE DIFFRACTION BY TWO HALF-PLANES AND WEDGE WITH THE FRACTIONAL BOUNDARY CONDITION","authors":"V. Tabatadze, K. Karaçuha, E. Veliyev, E. Karaçuha","doi":"10.2528/pierm20020503","DOIUrl":"https://doi.org/10.2528/pierm20020503","url":null,"abstract":"In this article, the diffraction of plane electromagnetic waves by double half-planes with fractional boundary conditions is considered. As particular cases, the diffractions by wedges and corners are considered for different values of fractional orders. The results are compared to the analytical ones. The interesting properties of wedge diffraction are outlined for intermediate fractional orders.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"28 1","pages":"1-10"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79191659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Metasurfaces enable a new avenue to create electrically thin multi-layer structures, on the order of one-tenth the central wavelength (λc), with engineered responses. Altering the subwavelength spatial features, e.g., λc/80, on the surface leads to highly tunable electromagnetic scattering characteristics. In this work, we develop an ultra-wideband frequency selective metasurface (FSmS) that completely encompasses the Ku-band from 12–18 GHz with steep band edges. The geometrical structure of the metasurfaces is optimized by a multi-objective genetic algorithm mimicking evolutionary processes. Analysis is performed from oneto four-layer metasurface structures with various thicknesses. Computational electromagnetic simulations for these frequency selective metasurfaces are presented, discussed, and experimentally validated. The concepts presented in this work can be applied to design metasurfaces and metamaterials from the microwave to the optical regimes.
{"title":"MULTI-OBJECTIVE GENETIC ALGORITHM OPTIMIZATION OF FREQUENCY SELECTIVE METASURFACES TO ENGINEER KU-PASSBAND FILTER RESPONSES","authors":"K. Allen, D. Dykes, D. Reid, Richard Lee","doi":"10.2528/PIER19112609","DOIUrl":"https://doi.org/10.2528/PIER19112609","url":null,"abstract":"Metasurfaces enable a new avenue to create electrically thin multi-layer structures, on the order of one-tenth the central wavelength (λc), with engineered responses. Altering the subwavelength spatial features, e.g., λc/80, on the surface leads to highly tunable electromagnetic scattering characteristics. In this work, we develop an ultra-wideband frequency selective metasurface (FSmS) that completely encompasses the Ku-band from 12–18 GHz with steep band edges. The geometrical structure of the metasurfaces is optimized by a multi-objective genetic algorithm mimicking evolutionary processes. Analysis is performed from oneto four-layer metasurface structures with various thicknesses. Computational electromagnetic simulations for these frequency selective metasurfaces are presented, discussed, and experimentally validated. The concepts presented in this work can be applied to design metasurfaces and metamaterials from the microwave to the optical regimes.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"26 1","pages":"19-30"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78243156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mingxing Du, Yuxiao Zhang, Hongbin Wang, Ye Tian, Z. Ouyang, Kexin Wei
This paper proposes an improved method for calculating static capacitance between two conductors with circular cross-sections in inductor windings. It considers the effects of electric field coupling and energy distribution on static capacitance. In this paper, the capacitance between two conductors in inductor windings is calculated by the improved calculation method and finite-element method (FEM), respectively. The relative error of the improved calculation method is between 0.11% and 4.51% compared to the FEM. In order to verify the effectiveness of this method for inductor winding, the orthogonal stacking winding and staggered stacking winding are chosen as calculation examples to accurately predict the static capacitance of multi-layer circular-section induction coils. Finite element models for the two types of windings are built to determine the capacitances for our 3 × 3 array arrangement winding. The results show that the improved calculation method proposed in this paper highly conforms to FEM. Finally, we adopt an air-cored cylindrical inductor winding for experimental verification, and the improved calculation method is proved to be correct.
{"title":"AN IMPROVED CALCULATION METHOD FOR STATIC CAPACITANCE IN INDUCTOR WINDINGS","authors":"Mingxing Du, Yuxiao Zhang, Hongbin Wang, Ye Tian, Z. Ouyang, Kexin Wei","doi":"10.2528/PIERC20051203","DOIUrl":"https://doi.org/10.2528/PIERC20051203","url":null,"abstract":"This paper proposes an improved method for calculating static capacitance between two conductors with circular cross-sections in inductor windings. It considers the effects of electric field coupling and energy distribution on static capacitance. In this paper, the capacitance between two conductors in inductor windings is calculated by the improved calculation method and finite-element method (FEM), respectively. The relative error of the improved calculation method is between 0.11% and 4.51% compared to the FEM. In order to verify the effectiveness of this method for inductor winding, the orthogonal stacking winding and staggered stacking winding are chosen as calculation examples to accurately predict the static capacitance of multi-layer circular-section induction coils. Finite element models for the two types of windings are built to determine the capacitances for our 3 × 3 array arrangement winding. The results show that the improved calculation method proposed in this paper highly conforms to FEM. Finally, we adopt an air-cored cylindrical inductor winding for experimental verification, and the improved calculation method is proved to be correct.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"1 1","pages":"25-36"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88483176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Combeau, N. Noé, F. Gaudaire, Steve Joumessi Demeffo, J. Dufour
With the increasing number of mobile phone users, new services, and mobile applications, the proliferation of radio antennas has raised concerns about human exposure to electromagnetic waves. This is now a challenging topic to many stakeholders such as local authorities, mobile phone operators, citizen, and consumer groups. Thus, the prediction of exposure map at urban scale is a very important requirement to find a relevant indicator of the real exposure. In this paper, we propose a monitoring solution for electromagnetic field (EMF) exposure based on a numerical modeling of the radio wave propagation radiated by mobile telephony base stations. The accuracy of this tool directly depends on the input data precision, such as location of base station antennas or their radiation pattern, which are often poorly known. These data are therefore refined by an optimization algorithm fed by a lot of information, such as the indication of the received signal strength (RSSI) measured directly from users’ smartphones, which are used as probes. Results show that this method significantly improves the precision of unknown data concerning mobile base stations and the accuracy of exposure maps at urban scale.
{"title":"A NUMERICAL SIMULATION SYSTEM FOR MOBILE TELEPHONY BASE STATION EMF EXPOSURE USING SMARTPHONES AS PROBES AND A GENETIC ALGORITHM TO IMPROVE ACCURACY","authors":"P. Combeau, N. Noé, F. Gaudaire, Steve Joumessi Demeffo, J. Dufour","doi":"10.2528/pierb20020404","DOIUrl":"https://doi.org/10.2528/pierb20020404","url":null,"abstract":"With the increasing number of mobile phone users, new services, and mobile applications, the proliferation of radio antennas has raised concerns about human exposure to electromagnetic waves. This is now a challenging topic to many stakeholders such as local authorities, mobile phone operators, citizen, and consumer groups. Thus, the prediction of exposure map at urban scale is a very important requirement to find a relevant indicator of the real exposure. In this paper, we propose a monitoring solution for electromagnetic field (EMF) exposure based on a numerical modeling of the radio wave propagation radiated by mobile telephony base stations. The accuracy of this tool directly depends on the input data precision, such as location of base station antennas or their radiation pattern, which are often poorly known. These data are therefore refined by an optimization algorithm fed by a lot of information, such as the indication of the received signal strength (RSSI) measured directly from users’ smartphones, which are used as probes. Results show that this method significantly improves the precision of unknown data concerning mobile base stations and the accuracy of exposure maps at urban scale.","PeriodicalId":54551,"journal":{"name":"Progress in Electromagnetics Research-Pier","volume":"37 1","pages":"111-129"},"PeriodicalIF":6.7,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80103584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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