• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.5
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• pp.54-63
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• 2011

This paper presents the improving impedance charactersitics of a planar monopole antenna with a vertical ground plane. For improving impedance characteristics, we used the effect of a vertical ground plane. To analyze the effect of vertical ground plane, we proposed the dipole antenna mode. the impedance characteristics of planar monopole antenna are improved by correlation between monopole antenna and vertical ground plane, based on each operating mode. Our analysis indicates can improve the impedance characteristics of varying planae monopole antennas.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.24 no.3
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• pp.109-114
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• 2024

The effect of inter-channel coupling in multi-channel monopulse receiver is expected to increase by miniaturization trend of receiver. Therefore, in this paper, calibration method is proposed to compensation for inter-channel coupling in receiver of monopulse radar. And it can prevent distortion of angle information of target. Hardware configuration that consists of switch, directional coupler, matched load, ADC(Analog to Digital Converter), signal source of calibration is proposed to calibration. Total nine scattering parameters are obtained by controlling the switch and signal source of calibration. After that, method for restoring the undistorted signal is proposed using the mathematical relationship between the monopulse signal output from the antenna and the monopulse signal passing through the multi-channel receiver in the presence of inter-channel coupling.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.21-26
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• 2005

Experimental researches on the preparation of porous polymeric monoliths in supercritical carbon dioxide have been performed and the effects of monomer and polymerization parameters on the physical properties of the monolith prepared were examined. Polymerizations were carried out in the high pressure stainless steel reactor with sapphire window to show the phase change during the polymerization reaction, and continuous and dry porous monolithic polymer could be obtained. The specific surface area of monolithic polymer increased with monomer contents in reaction mixture and reaction pressure. The Rockwell hardness could be enhanced by the addition of co-monomer MMA in reaction mixtures.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.1
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• pp.18-26
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• 2007

A development of monopropellant thruster for microsatellite that uses concentrated hydrogen peroxide is described. Catalyst, the most important component in the thruster, was prepared and coated on a monolith honeycomb. Performance evaluation of thruster was peformed by considering the efficiency of characteristic velocity and ignition delay. As a result, 96.0% of $C^*$ efficiency was obtained at designed propellant flowrate and steady state operating condition.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.1
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• pp.107-114
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• 2021

In this paper, a planar transistor oscillator for X-band using a newly proposed L-shaped monopole slot resonator is proposed. For planar design, an L-shaped monopole slot with an open-end is used as a resonator for a transistor oscillator. As a result of the simulated design of the resonator in three stages, a high Q value of 1169.84 and a high insertion loss of 49.934 dB were identified. The results of the final design and manufactured oscillator measurements confirmed that the oscillation output is greater than 7 dBm and has good phase noise characteristics of -58 dBc/Hz at 100 kHz offset. The proposed oscillator is planar and has the advantage of being directly applicable to microwave integrated circuit technology. It also has the advantage of being able to reduce its size as it can only be implemented in microstrip form without additional devices such as metal cavities and tuning screws in 3D structures, as in the case of a DRO (dielectric resonance oscillator).

• Journal of IKEEE
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• v.8 no.1 s.14
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• pp.39-46
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• 2004

This paper presents the realization schemes for a multipurpose coherent mono-pulse radar Simulator with extendable features. We developed and installed the TSG(Timing Signal Generator) board which can simulate a mechanically rotate signal of antenna, an operation timing signal of pulse radar and target signal, to operate the simulator without real target in the indoor environment. Also, with the insertion of the radar signal processor, it came to be easy to achieve the addition of radar function algorithms, to rebuild or extend the multi-DSP Architecture into the simulator. Throughout the simulation results, we verified that the designed coherent mono-pulse radar simulator can exactly display a moving target on the realistic monitor(RD 9800).

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.6
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• pp.47-53
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• 2023

In this paper, We designed a waveguide-type feed structure that converts millimeter wave dual-polarized signals into monopulse signals and presented a manufacturing method. At millimeter-wave such as the W band, the size of the waveguide is very small, making it very difficult to manufacture complex structures. Therefore, because manufacturability is important for the waveguide-type feed structure in the millimeter-wave, electro forming and diffusion bonding were proposed and verified in this study. The designed monopulse feed structure consists of eight 180° hybrids that combine 90° hybrids and self-compensating phase shifters, and four OMTs to separate dual polarization. The designed feed structure was designed to facilitate electro forming and diffusion bonding, and the manufactured feed structure was verified through a network analyzer. It was confirmed that the two proposed production methods produce a monopulse signal well through the measured magnitude and phase of the port.

• KOMUNHWA
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• no.62
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• pp.87-112
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• 2003

The purpose of this study is to know about history and significance of Kosode elementally. Kosode the original form of Kimono, and it was dressed by the upper class in the Heian Period$(794\~857)$. Everyone could wear Kosode after the Onin's wa

• The Research Journal of the Costume Culture
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• v.23 no.4
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• pp.595-603
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• 2015

The influence of Japonism, which is the post-mid-$19^{th}$ century phenomenon of appreciating and preferring the Japanese style that manifested all across Western art, started to grow as a result of the active open-door policy of Japan at this time. As all areas of Japanese arts and culture, such as paintings, sculptures and theater plays, influenced Europe and America, this influence developed into a cultural phenomenon that was reflected even in fashion. The characteristic elements of the kimono first expanded from Paris and showed a similar silhouette to that of the traditional kimono in the early $20^{th}$ century, but towards the middle and the end of the century, kimono sleeves that were connected as one piece without a connecting seam line between the sleeve and bodice started to appear. The foundation of this research focuses on the design characteristics of kimono sleeves that can be seen in $20^{th}$-century fashion, and five varying kimono sleeve jackets and coats based on these formative characteristics were designed. Each design had a gusset design added, which improved the external and mobility problems inherent in kimono sleeve patterns, while at the same time serving as a proposal for new design element applications. Additionally, through various changes to and attempts at designs using the kimono sleeve as a limiting factor, new design possibilities were explored.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.1018-1024
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• 2001

In this paper, an array antenna is designed far base station of a street micro-cell in urban areas. It has a rectangular radiation pattern. The current distribution of the array is decided by using a modified Woodward-Lawson sampling pattern synthesis method. To confirm the realization of the array antenna with rectangular pattern, 12 array antenna with a planar type monopole fed by stripline is fabricated and measured. In the results of the measured values, H-plane pattern of the antenna nearly yields a rectangular radiation pattern.