• Proceedings of the KOR-BRONCHOESO Conference
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• 1982.05a
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• pp.11.1-11
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• 1982

Foreign bodies in the esophagus is a common problem encountered in the ENT field. Small toys were the most common type of esophageal foreign body found in Korea until the government started making coins. Although 10 won coins are most commonly found, there is a tendency for an increased percentage of 100 won coins parallel with the economic development of the country. Recently, the authors experienced a very intersting case in which a 7 year-old child had a 5 won coin lodged horizontally at a level of the third esophageal constriction portion for 4 years, which eventually resulted in esophageal dilatation. A review of the literature of this subject is included.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.9
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• pp.849-854
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• 2006

In this study, the hybrid electrodes, composed of the activated carbon powders and $LiCoO_{2}$ powders, were prepared as a cathode for the high-capacitance type hybrid capacitor, and the electrochemical properties of the hybrid electrodes were examined in terms of the weight composition and the milling time of $LiCoO_{2}$ powders. The specific volumetric capacities were increased with increasing of the composition of $LiCoO_{2}$ powders in the hybrid electrodes. On the other hand the coin cell capacitors, using the hybrid electrodes with $LiCoO_{2}$ poweders milled for 200 h, have exhibited the lower internal resistivities and the better capacity retention after 100 charge-discharge cycle than those of the coin cell capacitors using the hybrid electrodes with raw $LiCoO_{2}$ powders.

• Journal of the Korean Electrochemical Society
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• v.15 no.3
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• pp.198-205
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• 2012

Carbon-supported manganese oxide composite were fabricated as an air cathode material for Li-air batteries by hydrothermal method. The composite materials of carbon and manganese oxide were investigated by the implementation of X-ray diffraction, FE-SEM and BET surface area measurer. The manganese oxide synthesized at $170^{\circ}C$ for 12 h has a rod like shape morphology with 40-50 nm long in size. A Lithium-air battery with coin type, of which electrodes are composed of cathode composite materials synthesized $170^{\circ}C$-12 h and lithium metal anode, reveals its first discharge capacity of 3,852 mAh/g and four discharge-charge cycles.

• Korean Journal of Materials Research
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• v.33 no.10
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• pp.430-438
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• 2023

In this study, we synthesized pH-controlled resorcinol-formaldehyde (RF) gels through the polymerization of two starting materials: resorcinol and formaldehyde. The prepared RF gels were dried using an acetone substitution method, and they were subsequently carbonized under nitrogen atmosphere to obtain carbon xerogels (CX_Y) prepared at different pH (Y). The carbon xerogels were utilized as active materials for coin-type organic supercapacitor electrodes to investigate the influence of pH on the electrochemical properties of the carbon xerogels. The carbon xerogels prepared at lower pH (CX_9.5 and CX_10) exhibited sufficient particle growth, with a three-dimensional network of particles during the RF gel formation, resulting in the development of abundant mesopores. Conversely, the carbon xerogels prepared at higher pH (CX_11 and CX_12) retained densely packed structures of small particles, leading to pore collapse and low specific surface areas. Consequently, CX_9.5 and CX_10 showed high specific surface areas, and provided ample adsorption sites for the formation of electric double layers with electrolyte ions. Moreover, the three-dimensional particle network in CX_9.5 and CX_10 significantly enhanced electrical conductivity. The presence of well-developed mesopores in these materials further facilitated the effective transport of electrolyte ions, contributing to their superior performance as organic supercapacitor electrodes. This study confirmed that pH-controlled carbon xerogels are one of the promising active materials for organic supercapacitor electrodes. Furthermore, we concluded that pH during RF gel formation is a crucial factor determining the electrode performance of the carbon xerogels, highlighting the need for precise pH control to obtain high-performance carbon xerogel electrodes.

• Journal of the Korea Society of Computer and Information
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• v.28 no.5
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• pp.49-56
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• 2023

Currently, e-commerce is changing from a digital twin to a metaverse world. The metaverse world is an intermediate form between virtual and real worlds and is operated as a coin-based meta-commerce. In this meta-commerce world, blockchain-based NFT coins are used when trading items (contents). In this study, we studied how to issue a large number of NFT coins (certification) rather than issuing a single type of NFT. The research method was designed to produce content layer-based and automatically create the desired quantity using a mass NFT index and automatic generation method. In this study, a layer overlap method (background, body, etc.) was used with a Phyton-based program for mass minting. As a result, it can be used as a blockchain-based certificate that can prove a group of many people. In addition, the content created with the NFT index was registered on the NFT sales site to confirm its utilization and value.

• Korean Institute of Interior Design Journal
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• v.25 no.1
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• pp.142-150
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• 2016

This study examined the general housing awareness and awareness on house sharing of college students who are present residents as well as potential residents of shared houses. To achieve this purpose, structured questionnaires were used as a survey tool to understand students' awareness on housing and opinions on house sharing including a range of space sharing, preferences on house mates, and demands on services and facilities. The survey was conducted of college students in Busan, and the data were analyzed by the PASW Statistics 18.0 program. The findings of this study are as follows: 1) The housing awareness was categorized into seven factors by factor analysis. The subjects valued 'personality factor' in the housing awareness. 2) Regarding preference of house mate type, participants preferred a person who has similar lifestyle and in the same gender. 3) As for the space sharing, the subjects didn't want to share a bathroom and shower. Also, they preferred medium or large scale dormitory layout type to small sized apartment type. 4) The most positive aspect of house sharing was 'Reduction of rental and maintenance cost'. On the other hand, 'Difference of daily life pattern' was the most negative aspect of house sharing. 5) In case of services and community spaces, they preferred 'delivery storage service' and 'coin-operated laundry facility'.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2915-2918
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• 2003

The increase of vehicles stagnations leads to the increasing attention to the way customers pay and a large number of projects on electronic cash system. Tranport system is comprised of a number of advanced technologies, including information processing, communications, control, and electronics. Recently many research on a system which provides contact in order to protect driver's vehicle passage have been carried out. And some potential problems from that system are being reviewed by electronic cash system. In this papers, we suggest RF protocol developing technology using the concept of electronic cash. ATM electronic cash developing is consist of component of pre-developed coin throw, Integration of component using its, and production of more requirement-satisfactory ITS solution. Result increase 15∼40％ pre-type vehicles stagnations. Especially, we expect this proposed concept would be well adapted to our national environments.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.133-136
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• 2003

The increase of vehicles stagnations leads to the increasing attention to the way customers pay and a large number of projects on electronic cash system. Tranport system is comprised of a number of advanced technologies, including information processing, communications, control, and electronics. Recently many research on a system which provides contact in order to protect driver's vehicle passage have been carried out. And some potential problems from that system are being reviewed by electronic cash system. In this papers, we suggest Rf protocol developing technology using the concept of electronic cash. ATM electronic cash developing is consist of component of Pre-developed coin throw, integration of component using its, and production of more requirement-satisfactory ITS solution. Result increase $15{\sim}40%$ pre-type vehicles stagnations. Especially, we expect this proposed concept would be well adapted to our national environments.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.128-132
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• 2003

The increase of vehicles stagnations leads to the increasing attention to the way customers pay and a large number of projects on electronic cash system. Transport system is comprised of a number of advanced technologies, including information processing, communications, control, and electronics. Recently many research on a system which provides contact in order to protect driver's vehicle passage have been carried out. And some potential problems from that system are being reviewed by electronic cash system. In this papers, we suggest RF protocol developing technology using the concept of electronic cash. ATM electronic cash developing is consist of component of pre-developed coin throw, integration of component using its, and production of more requirement-satisfactory ITS solution. Result increase 15-40% pre-type vehicles stagnations. Especially, we expect this proposed concept would be well adapted to our national environments

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.557-560
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• 2003

The increase of vehicles stagnations leads to the increasing attention to the way customers pay and a large number of projects on electronic cash system. Tranport system is comprised of a number of advanced technologies, including information processing, communications, control, and electronics. Recently many research on a system which provides contact in order to protect driver's vehicle passage have been carried out. And some potential problems from that system are being reviewed by electronic cash system. In this papers, we suggest RF protocol developing technology using the concept of electronic cash. ATM electronic cash developing is consist of component of pre-developed coin throw, integration of component using its, and production of more requirement-satisfactory ITS solution. Result increase 15~40% pre-type vehicles stagnations. Especially, we expect this proposed concept would be well adapted to our national environments.