Publications by authors named "Jae Young Chung"

This paper presents the introduction, design, and experimental validation of two small helical antennae. These antennae are a component of the surface acoustic wave (SAW) sensor interrogation system, which has been miniaturized to operate at 915 MHz and aims to improve the performance of wireless passive SAW temperature-sensing applications. The proposed antenna designs are the normal-mode cylindrical helical antenna (CHA) and the hemispherical helical antenna (HSHA); both designed structures are developed for the ISM band, which ranges from 902 MHz to 928 MHz.

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Intermediate phase shifting is a footprint- and cost-reduction technique for reconfigurable feed networks. These feed networks are utilized in antenna arrays to perform electrical beam steering. In intermediate phase shifting, a phase shifter is shared between two adjacent antennas.

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To demonstrate that the silicone-based polymer polydimethylsiloxane (PDMS) is suitable as a substrate for flexible/wearable antennae and sensors, an investigation of its various properties was carried out. The substrate was first developed in compliance with the requirements, and then its anisotropy was investigated using an experimental bi-resonator approach. This material exhibited modest but discernible anisotropy, with values of ~6.

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An adjustable 4×4 antenna array with electrical beam steering and polarization control is presented. Here, adjustability means the ability to correct the beam steering angle post-calibration. The objective is to improve the steering accuracy which is critical in point-to-point communication as inaccuracy will cause transmission failure due to a missed target.

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An end-fire radiating implantable antenna with a small footprint and broadband operation at the frequency range of 3-5 GHz is proposed for high-data-rate wireless communication in a brain-machine interface. The proposed Vivaldi antenna was implanted vertically along the height of the skull to avoid deformation in the radiation pattern and to compensate for a gain-loss caused by surrounding lossy brain tissues. It was shown that the vertically implanted end-fire antenna had a 3 dB higher antenna gain than a horizontally implanted broadside radiating antenna discussed in recent literature.

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High pharmacokinetic variability of voriconazole is mainly explained by CYP2C19 phenotype, but there are still unknown factors affecting the variability. In this study, the effect of solute carrier organic anion transporter family member 2B1 (SLCO2B1) genotype on the pharmacokinetics (PKs) of voriconazole was evaluated in 12 healthy CYP2C19 poor metabolizers after a single administration of voriconazole 200 mg intravenously and orally. In addition, the influence of CYP3A4 enzyme activity was also explored.

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This paper proposes a novel in vitro exposure system operating at millimeter-wave (mmWave) 28 GHz, one of the frequency bands under consideration for fifth generation (5G) communication. We employed the field uniformity concept along cross-sectional observation planes at shorter distances from the radiation antenna for better efficiency and a small-size system. A choke-ring antenna was designed for this purpose in consideration of a wider beamwidth (BW) and a symmetric far-field pattern across three principal planes.

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Background: Mandibular angle reduction surgery is widely used for aesthetic purposes. Because inferior alveolar nerve injury is a common complication of this surgery, the anatomical location of this nerve must be known before surgery. This study investigated the relative location of the inferior alveolar nerve in mesofacial and brachyfacial groups.

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Background: Although interest in flap surgery has increased, a satisfactory research study on supportive drugs or methods for flap surgery has not been seen in the literature thus far. Despite several studies using botulinum toxin A for flap surgery being reported, their efforts to clarify the mechanisms are not sufficient. Therefore, the authors have studied the effect of botulinum toxin A on random cutaneous flap survival in a rat model under the hypothesis that it affects the microvascular system.

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Cephalhematoma is a collection of blood beneath the periosteum of the bones in the cranial vault. The treatment strategy of most cephalhematoma is conservative. However, in cases of ossified cephalhematoma causing deformities of skull, surgical management is indicated.

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The infracture technique for reduction malarplasty has been widely used as an aesthetic surgical procedure in northeast Asia. Since 1988, the authors' original method of infracture technique was performed through the combined approach of intraoral and temporopreauricular incision, which may leave a rather long scar on the temporal region. To shorten the external scar, a new technique using a short preauricular incision instead of a long temporopreauricular incision was developed.

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Gene cassettes of class 1 integrons in Escherichia coli isolates from urine specimens collected in Korea during the last 2 decades were characterized. intI1 was detected in 54% of the isolates, yet gene cassette regions were amplified in only 43% of the isolates. intI2 was detected in 29 (5%) isolates, and no intI3 was detected in this study.

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