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Yecheon, South Korea

Son H.-W.,Kyungpook National University | Kim B.-M.,Gyeongbuk Provincial College | Hong J.-P.,Kyungil University | Cho Y.-K.,Kyungpook National University
Journal of Electrical Engineering and Technology | Year: 2015

In this paper, a rectangular waveguide probe with a ridge-loaded straight slot (RLSS) is presented for a near-field scanning microwave microscope (NSMM). The RLSS is located laterally at the end wall of the cavity and is loaded on double ridges in a narrow straight slot to improve the spatial resolution compared with a straight slot. The probe consists of a rectangular cavity with an RLSS and a feed section of a WR-90 rectangular waveguide. When the proposed NSMM is located at distance of 0.1mm in front of a substrate without patches or strips, the simulated full width at half maximum (FWHM) of the probe improve by approximately 31.5% compared with that of a straight slot without ridges. One dimensional scanning of the E-plane on a sample under test was conducted, and the reflection coefficient of the near-field scanning probe is presented. © The Korean Institute of Electrical Engineers. Source

Kim B.-M.,Gyeongbuk Provincial College | Son H.-W.,Kyungpook National University | Cho Y.-K.,Kyungpook National University | Hong J.-P.,Kyungil University
Journal of the Korean Physical Society | Year: 2014

We present a simple method for efficient modeling of the tunneling effect in an Epsilon Near Zero (ENZ) channel waveguide based on a transmission-line model. The proposed ENZ channel uses a double-ridge rectangular waveguide (RWG) and is located in the middle of the input-output standard rectangular waveguides (IORWG). The height of the channel waveguide is much smaller than that of the IORWG. The detailed design of the ENZ channel is presented, and the optimum length for tunneling phenomena is calculated. These theoretical studies highlight the substantial differences between this unique tunneling phenomenon and higher-frequency Fabry-Perot resonances. We perform a simulation for the designed ENZ channel by using a commercial FEM simulator. The simulated and the measured results for the fabricated ENZ channel structure are in good agreement. © 2014, The Korean Physical Society. Source

Lee J.H.,Gyeongbuk Provincial College | Lee Y.M.,Yeungnam University | Oh S.-H.,North Carolina A&T State University | Son H.J.,Gyeongbuk Livestock Research Institute | And 3 more authors.
Asian-Australasian Journal of Animal Sciences | Year: 2014

The purpose of this study was to estimate genetic parameters of ultrasound measurements for longissimus dorsi muscle area (LMA), backfat thickness (BFT), and marbling score (MS) in Hanwoo cows (N = 3,062) at the ages between 18 and 42 months. Data were collected from 100 Hanwoo breeding farms in Gyeongbuk province, Korea, in 2007 and 2008. The cows were classified into four different age groups, i.e. 18 to 22 months (the first pregnancy period), 23 to 27 (the first parturition), 28 to 32 (the second pregnancy), and 33 to 42 (the second parturition), respectively. For each age group, a multi-trait animal model was used to estimate variance components and heritabilities of the three traits. The averages of LMA, BFT, and MS measurements across the cows of all age groups were 50.1 cm2, 4.62 mm, and 3.04, respectively and heritability estimates were 0.09, 0.10, and 0.08 for the respective traits. However, when the data were analyzed in different age groups, heritability estimates of LMA and BFT were 0.24 and 0.47, respectively, for the cows of 18 to 22 months of age, and 0.21 for MS in the 28 to 32 months old cows. When the cows of all age groups were used, the estimates of genetic (phenotypic) correlations were 0.43 (0.35), ±0.06 (0.34) and 0.21 (0.32) between LMA and BFT, LMA and MS, and BFT and MS, respectively. However, in the cow age group between 28 and 32 (18 and 22) months, the estimates of genetic (phenotypic) correlations were 0.05 (0.29), ±0.15 (0.24) and 0.38 (0.24), for the respective pairs of traits. These results suggest that genetic, environmental, and phenotypic variations differ depending on cow age, such that care must be taken when ultrasound measurements are applied to selection of cows for meat quality. © 2014 by Asian-Australasian Journal of Animal Sciences. Source

Kim B.M.,Gyeongbuk Provincial College | Hwang K.-P.,Samsung | Cho Y.K.,Kyungpook National University
IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) | Year: 2011

In this paper, a small planar bow-tie antenna fed by a flanged rectangular waveguide is investigated using the finite element method (FEM). The bow-tie antenna has two triangular conductive strips separated by a gap and each strip has an inverted triangular hole. Numerical results show that this bow-tie antenna can generate intense electrical field spots below the diffraction limit with transmission efficiency approaching unity. Antenna characteristics of the bow-tie antenna with holes are compared with those of the bow-tie antenna without holes as well as the flanged rectangular waveguide feed only. © 2011 IEEE. Source

Lee H.G.,Yonsei University | Cho N.-C.,Korea Institute of Science and Technology | Jeong A.J.,Seoul National University | Li Y.-C.,Daejeon University | And 9 more authors.
Journal of Investigative Dermatology | Year: 2016

T-cell-mediated immune responses play an important role in body protection. However, aberrantly activated immune responses are responsible for inflammatory and autoimmune diseases. The regulation of pathologic immune responses may be a potential therapeutic strategy for the treatment of these diseases. Despite that multiple pharmacologic properties of benzoxathiole derivatives have been defined, the molecular mechanisms underlying these properties remain to be clarified. Here, we demonstrated the benzoxathiole derivative 2-cyclohexylimino-6-methyl-6, 7-dihydro-5H-benzo[1, 3]oxathiol-4-one (BOT-4-one) regulated immune responses and ameliorated experimentally induced inflammatory skin diseases both in vitro and in vivo. BOT-4-one inhibited the differentiation of CD4+ T-cell subsets by regulating the expression and production of T-cell lineage-specific master transcription factors and cytokines and activating the signal transducer and activator of transcription proteins. In addition, BOT-4-one inhibited TCR-mediated Akt and NF-kB signaling. Topical application of BOT-4-one ameliorated experimentally induced inflammatory skin diseases in mice models such as 2, 4, 6-trinitrochlorobenzene-induced contact and atopic dermatitis and IL-23-induced psoriasis-like skin inflammation. Our study demonstrated that BOT-4-one ameliorates inflammatory skin diseases by suppressing the pathogenic CD4+ T cell differentiation and overall immune responses. © 2015 The Authors. Source

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