• Journal of Sensor Science and Technology
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• v.22 no.4
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• pp.276-280
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• 2013

The purpose of this paper is to diagnose osmidrosis visually and quantify the extent of osmidrosis. To achieve this, we designed the diagnosis method of osmidrosis using electronic nose system. The developed electronic nose system use principal component analysis for visualization of osmidrosis and fuzzy c-means algorithm for quantification. To confirm the efficiency of electronic nose system for osmidrosis diagnosis, we obtained samples from 34 volunteers and compared our experiment results with the doctor's diagnosis, and we met with successful results.

• Transactions on Electrical and Electronic Materials
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• v.8 no.1
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• pp.46-50
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• 2007

We have studied the nematic liquid crystal (NLC) alignment effects on a nitrogen-doped diamond-like carbon (NDLC) thin film layer with ion beam irradiation. The pretilt angle for NLC on the NDLC surface with ion beam exposure was observed below 1 degree. Also, we had the good LC alignment characteristics on the NDLC thin films with ion beam exposure of 1800 eV. In thermal stability experiments, the alignment defect of the NLC on the NDLC surface with ion beam irradiation above annealing temperature of $250^{\circ}C$ can be observed. Therefore, the good thermal stability and LC alignment for NLC by ion beam aligned NDLC thin films can be achieved.

• Nuclear Engineering and Technology
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• v.56 no.4
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• pp.1538-1543
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• 2024

The importance of determining the radon exhalation rate from water surface is emphasized by the increased use of radon and its daughter products as tracers in large-scale circulation studies of the atmosphere. There were many methods to measure radon exhalation from water surface. With the development of radon exhalation rate measurement methods and instruments on the surface of the soil, the rock and building materials, so the radon exhalation rate from water surface can be more accurately measured by applying these improved methods and instruments. In this paper, a cuboid accumulation chamber surrounded by foam boards and a RAD7 were used to measure the radon exhalation rate on the water surface at three different positions by Yixin lake. Each measurement was performed 2 h. The radon exhalation rate from the water surface was about 6 × 10^-3 Bq m^-2s^-1. The thoron exhalation rate from the water surface also can be estimated, it is about 0.16 Bq m^-2s^-1. These results hint that the radon transmission from the lake bottom soil to water and then into the atmosphere.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.7
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• pp.438-442
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• 2014

Channel length dependence of NBTI (negative bias temperature instablilty) and CHC (channel hot carrier) characteristics in PMOSFET is studied. It has been considered that HC lifetime of PMOSFET is larger than NBTI lifetime. However, it is shown that CHC degradation is greater than NBTI degradation for PMOSFET with short channel length. 1/f noise and charge pumping measurement are used for analysis of these degradations.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1777-1781
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• 2003

• Journal of the Korean Physical Society
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• v.73 no.9
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• pp.1362-1369
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• 2018

A method aimed at improving the beam-wave interaction efficiency by changing the coupling slot configuration has been proposed in the study of extended interaction oscillators (EIOs). The dispersion characteristics, coupling coefficient and interaction impedance of the high-frequency structure based on different types of coupling slots have been investigated. Four types of coupled cavity structures with different layouts of the coupling slots have been compared to improve the beam-wave interaction efficiency, so as to analyze the beam-wave interaction and practical applications. In order to determine the improvement of the coupling slot to a coupled cavity circuit in an EIO, we designed four nine-gap EIOs based on the coupled cavity structure with different coupling slot configurations. With different operating frequencies and voltages takes into consideration, beam voltages from 27 to 33 kV have been simulated to achieve the best beam-wave interaction efficiency so that the EIOs are able to work in the $2{\pi}$ mode. The influence of the Rb and the ds on the output power is also taken into consideration. The Rb is the radius of the electron beam, and the ds is the width of the coupling slot. The simulation results indicate that a single-slot-type EIO has the best beam-wave interaction efficiency. Its maximum output power is 2.8 kW and the efficiency is 18% when the operating voltage is 31 kV and electric current is 0.5 A. The output powers of these four EIOs that were designed for comparison are not less than 1.7 kW. The improved coupling-slot configurations enables the extended interaction oscillator to meet the different engineering requirements better.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.175-175
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.164-164
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.90-90
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• 2003

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.306-306
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• 2003