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This article proposes a novel compact wideband dielectric resonator antenna design that incorporates inhomogeneous material distribution in a cubic structure. Specifically, in this design, the cubic dielectric resonator antenna is divided into multiple small blocks, and a continuous genetic algorithm is employed to optimize the material property of each block in order to maximize the radiation bandwidth. As a result, a cubic dielectric resonator antenna with inhomogeneous material distributions is designed and tested. In measurement, the proposed compact dielectric resonator antenna design exhibits 64.9% impedance bandwidth (4.08–8 GHz), considerably higher than the bandwidth of the initial homogeneous dielectric resonator antenna. The maximum system gain achieved over the frequency range is 9 dB at 7 GHz, with a peak measured system efficiency of 90.6%.
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The Benjamin-Ono approximation for 2D gravity water waves with constant vorticity
This article is concerned with infinite depth gravity water waves with constant vorticity in two space dimensions. We consider this system expressed in position-velocity potential holomorphic coordinates. We show that, for low-frequency solutions, the Benjamin-Ono equation gives a good and stable approximation to the system on the natural cubic time scale. The proof relies on refined cubic energy estimates and perturbative analysis.
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- PAR ID:
- 10502242
- Publisher / Repository:
- Ars Inveniendi Analytica
- Date Published:
- Journal Name:
- Ars Inveniendi Analytica
- ISSN:
- 2769-8505
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.15781/chkn-sn69
