• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.2
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• pp.174-177
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• 2009

In this paper, an oscillator using dielectric-rod loaded cavity resonators with HTS(High Temperature Superconductor) end-plates was presented. It was operated at X-band. A two port cavity resonator was incorporated into a basic feedback loop oscillator configuration. A rutile loaded cavity resonator with HTS thin film end-plates was used to provide the quality factor between $10^4$ and $10^6$. A parallel feedback oscillator was constructed with a dielectric loaded cavity resonator, an amplifier, and a directional coupler. At 300 K, the experimental results showed the phase noise of -108 dBc/Hz at a 100 kHz offset frequency. At 26 K, the results was -118.8 dBc/Hz at same offset frequency.

• Korean journal of food and cookery science
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• v.13 no.3
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• pp.369-378
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• 1997

The consumption frequency, preference, purchasing behavior and satisfaction degree for bean sprout were surveyed from the housewives living in Seoul and Kyungki-do area. Most of the subjects (84.3%) took bean sprout less than 4 times per 21 meals. Major reasons for the rare consumption were the poor safety, habitual, and long cooking time, in deceasing order. Packed bean sprout was purchased more in Kyungki-do but unpacked was preferred in Seoul. While the major reason for purchasing unpacked bean sprout was the cheap price (57.8%), that for the packed was the safety (82.00). The most unsatisfactory factor for packed bean sprout was the high price, however, unlabelled additives were the primary concern for the unpacked. The satisfaction degree for the quality was higher in packed bean sprout compared with the unpacked. The most unsatisfactory factor for the quality of both packed and unpacked bean sprout was the overall acceptability, followed by texture, taste, and color.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1071-1074
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• 2002

In this paper, power quality analysis system is proposed where voltage or current waveforms are nonsinusoidal. The proposed system relies on the FFT algorithm to compute real and reactive power. The advantage of system is that harmonic analysis is carried out on a period of the input signal. The proposed system is based on FFT processor which is designed using VHDL(Very high-speed integrated circuit Hardware Description Language). In the design of FFT processor, radix- $2^2$ is adopted to reduce several complex multipliers for twiddle factor. Complex multiplier is implemented as only shifters and adders. Therefore, the system is able to have both high hardware efficiency and high performance.

• Fashion & Textile Research Journal
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• v.9 no.6
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• pp.589-594
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• 2007

The purpose of this study was to investigate the effect of Chemyon(social-face) on wedding consumption behavior. To perform this study, the questionnaires were administered to 305 women in seoul and the data were analyzed by Frequency, Factor Analysis, and Multiple Regression Analysis. In the result of factors analysis, Chemyon factors were divided into being formal, being conscious of other people, and being ashamed. Consumption behaviors were divided into pursuit of high quality, pursuit of individuality, pursuit of actual profit, and pursuit of fashion. In the result of this study, the more people give an account of formality, the more they behave pursuit of high quality and the less they behave pursuit of individuality and fashion. The more they make much importance of being conscious of other people, the more they pursue consumption of individuality and fashion. Also the more high consumption of fashion, the less they have being conscious of other people. Therefore we can find through this study that Chemyon has an influence on wedding-beauty consumption behavior.

• 전기의세계
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• v.21 no.3
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• pp.41-47
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• 1972

The requirements of a successful design for single phase induction motors with a high efficiency have, in recent years, led to the use of non-quadrature stator windings motors in which a high starting torque is a prime requisite. The capacitor motor is one of above machines in which various possible forms of asymmetry can be occur. These forms of asymmetry in the stator phase windings, encountered in machine designs, are 1) an asymmetrical disposition in space of their magnetic axes, 2) a difference in their effective number of turns, 3) a difference in the distribution of their coil groups per pole and 4) amounts of capacitance of an auxiary winding. In order to apply the effective performance prediction of these form to motors, mading of lower quality-domestic magnetic materials, the analysis and the experimental investigations of its sample motors are described in this paper. The utility of such a motor is demonstrated and it is shown that the effects- a good efficiency, good power factor and high starting torque-of the motor mechanism with non-quadrature stator phase windings can development disadvantages by using the lower quality-domestis magnetic materials.

• Journal of Korean Society for Quality Management
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• v.20 no.2
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• pp.137-142
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• 1992

MODAPTS has been widely used for establishing the standard time of manual works because of easy application of the system. However this system was developed based on MTM, winch was one of the low task standard. Also in this system, it usually becomes a cause of error in accuracy that all the simultaneous motions(SIMO) should be analyzed in the sequent motions of two hands. In order to improve the weak points of MODAPTS, the structure of time unit and SIMO of MODAPTS was researched, and HITMAP was developed on the basis of Work Factor System which was one of the high task standard. HITMAP is composed of 26 standard elements and it's time unit is MD(1MD=0.1 second) and MGSRMPS is the motion pattern of HITMAP. In this study HITMAP shows more than 95% of accuracy to WF. Therefor, it is expected that HITMAP can be used for the improvement of productivity and incentive systems.

• Progress in Superconductivity and Cryogenics
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• v.18 no.1
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• pp.46-49
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• 2016

The wireless power transfer (WPT) system using a magnetic resonance was based on magnetic resonance coupling of the transmission and the receiver coils. In these system, it is important to maintain a high quality-factor (Q-factor) to increase the transmission efficiency of WPT system. Our research team used a superconducting coil to increase the Q-factor of the magnetic resonance coil in WPT system. When the superconductor is applied in these system, we confirmed that transmission efficiency of WPT system was higher than normal conductor coil through a preceding study. The efficiency of the transmission and the receiver coil is affected by the magnetic shielding effect of materials around the coils. The magnetic shielding effect is dependent on the type, thickness, frequency, distance, shape of materials. Therefore, it is necessary to study the WPT system on the basis of these conditions. In this paper, the magnetic shield properties of the cooling system were analyzed using the High-Frequency Structure Simulation (HFSS, Ansys) program. We have used the shielding materials such as plastic, aluminum and iron, etc. As a result, when we applied the fiber reinforced polymer (FRP), the transmission efficiency of WPT was not affected because electromagnetic waves went through the FRP. On the other hand, in case of a iron and aluminum, transmission efficiency was decreased because of their electromagnetic shielding effect. Based on these results, the research to improve the transmission efficiency and reliability of WPT system is continuously necessary.

• Journal of Korean Society on Water Environment
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• v.29 no.5
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• pp.656-665
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• 2013

This research was conducted to investigate pollutant load unit factor from aquacultural farms. Pollutant load unit factors were investigated on the 13 kinds of fish type, i.e., Trout, Leather Carp, Eel, Carp, Cartfish, Freshwater Eel, Crucian Carp, Colored Carp, Sturgeon, Marsh Snail, Sweetfish, Pond Snail, Eriocheir Sinensis. Water qualities in aquacultural farms were investigated wide range of values by fish type and pollutant items. High BOD and COD values were observed at the Leather Carp (Ponded water system), Cartfish (Ponded water system) and Freshwater Eel (Recirculating System). TOC and DOC values were relatively high at the Freshwater Eel (Recirculating System) and Eriocheir Sinensis (Extensive). Eel (Ponded water system) and Freshwater Eel (Recirculating System) produced high concentrated nutrient pollutants, i.e., T-N, T-P. Pollutant load unit factors are dependent on fish type, aquacultural type, water quality items, etc. If some fishes have similar basic unit values, those could be applied for TMDLs as a group of fish having same pollutant load unit. The water quality concentrations of post treatment facilities' (mainly reservoir tank) effluent were higher than those of fish raising bath because of extracting pollutant from sediment in the reservoir tank. Therefore, it needs to the management and regulations about post treatment facilities.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.1
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• pp.72-81
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• 2009

This paper presents quasi-resonant type high power factor ac power supply for atmospheric pressure plasma cleaning system adopting three phase PFC boost converter and it's control method. The presented ac power supply consists of single phase H-bridge inverter, step-up transformer for generating high voltage and three phase PFC boost converter for high power factor on source utility. Unlikely to the traditional LC resonant converter, the propose one has an inductor inside only. A single resonant takes place through the inside inductor and the capacitor from the plasma load modeled into two series capacitor and one resistance. The quasi-resonant can be achieved by cutting the switching signal when the load current decrease to zero. To obtain power control ability, the propose converter controlled by two control schemes. One is the changing output pulse period scheme in the manner of PFM(Pulse Frequency Modulation) control. On the other, to provide more higher power to load, the DC rail voltage is directly controlled by the 3-phase PFC boost converter. The significant merits of the proposed converter are the uniform power providing capability for high quality plasma generation and low reactive power in AC and DC side. The proposed work is verified through digital simulation and experimental implementation.

• Journal of Korean Society for Quality Management
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• v.31 no.3
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• pp.37-61
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• 2003

The purpose of this study is to identify (1) the successful quality management activities of domestic enterprises contribute to enhancing both corporate and national competitiveness and that the corporate and national competitiveness are related each other; (2) and to have the government and the citizens as well as enterprises re-recognize the importance of quality management and encourage them to make aggressive investments on quality management. It was found in this study that the enterprises with quality management scheme showed better performance that those without quality management activities. It was also found that quality competitiveness is a key factor for the enhancement of the national competitiveness, and that although quality improvement is normally realized through efforts of private enterprises (a conventional paradigm), active government support and participation are absolutely necessary for the competitiveness of the nation and industries. Accordingly, the quality management should be recognized not only as part of business improvement activities, but as nationwide activities where public sectors including government enterprises, hospitals, schools, regional governments, media companies and citizens groups are involved. In order to build a high-quality nation in the 21st century, the quality improvement should be realized through concerted efforts of the people, enterprises and the government.