• Journal of the Society of Naval Architects of Korea
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• v.47 no.2
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• pp.196-209
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• 2010

For the analysis of Acoustic Target Strength(TS) that indicates the scattered acoustic intensity from the underwater vehicles, an analysis program that is applicable to scatterers insonified by spherical wave source in near field is developed. In this program, the Physical Optics(PO) method is embedded as a base component. To increase the accuracy of the program, multiple bounce effects based on Geometrical Optics(GO) method are applied. To implement multiple bounce effects, GO method is used together with PO method. In detail, GO method has a concern in the evaluation of the effective area, and PO method is involved in the calculation of Acoustic Target Strength for the final effective area that is evaluated by GO method. For the embodiment of near field spherical wave source originated multiple bounce effects, image source concept is implemented additively to the existing multiple bounce algorithm which assumes plane wave insonification. Various types of models are tested to evaluate the reliability of the developed program and finally, a submarine is analyzed as an arbitrary scatterer.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.53-56
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• 2000

An Electrical equipment is the noise source which makes a noise. So the optimally designed filter should be inserted in the equipment in order to reduce the noise. The noise source impedance is varied according to the frequency It effects on the CE noise. Knowing the magnitude of its impedance and inserting an EMI filter in the equipment we can estimate the insertion loss of the filter. SO it helpful in designing the EMI filter. The measurement method of a noise source impedance is proposed and verified by experiment.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.11B no.4
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• pp.164-168
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• 2001

In this paper voltage source FEA for hysteresis motor considering magnetic hysteresis characteristics is presented. The Preisach model is used as a hysteresis model. System matrix whose unknown variables are vector potentials and currents is formulated for voltage source. The stiffness matrix is maintained constant by using M-iteration method. Therefore the calculation time and efforts are reduced with Choleski direct method. Current waveform can be calculated for arbitrary voltage vaveform considering hysteresis effects.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.211-223
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• 2000

The atmospheric dispersion of a pollutant emitted from a hypothetical source located in the middle of the Yochon Industrial Estate was simulated by using the Regional Atmospheric Modeling System (RAMS). Four horizontally nested grids were employed: the coarsest one covered the southern part of the Korean Peninsula including Mt. Chiri and the finest one covered the Yochon Industrial Estate and the surrounding area. Wind fields were initially assumed horizontally homogeneous with a wind speed of 4m/s, the average for the Yosu area, and were developed without both external forces and diurnal changes in order to investigate the terrain-induced phenomena. Wind directions that could emphasize the terrain effects on the pollutant transport and that could carry pollutants to a highly-popluated area were selected for the dispersion study. A pollutant was released for 24hours from a grid-base volume source after a 24-h blank run for developing the wind field. The dispersion study showed that the pollutant from the present source location did not directly affect the Yosu City, but showed high concentrations at locations behind the hills 5 to 6 km away from the source according to wind directions. When the wind speed was low, close to calm condition, the pollutant was detected at upstream locations 6 to 7 km from the source. In comparison with the results from the RAMS simulation, the Industrial Source Complex Short-Term Model(ISCST3) predicted a narrow dispersion that was sensitive to the wind direction. When the wind velocity was affected by the local environment, the ISCST3 calculation using that data also gave a lop-sided result, which was different from the distribution of the pollutant reproduced by RAMS.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.3
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• pp.134-140
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• 2002

Deep submicron NMOSFETs with elevated source/drain can be fabricated using self-aligned selective epitaxial growth(SEG) of silicon for enhanced device characteristics with shallow junction compared to conventional MOSFETs. Shallow junctions, especially with the heartily-doped S/D residing in the elevated layer, give hotter immunity to Yt roll off, drain-induced-barrier-lowering (DIBL), subthreshold swing (SS), punch-through, and hot carrier effects. In this paper, the characteristics of both deep submicron elevated source/drain NMOSFETs and conventional NMOSFETs were investigated by using TSUPREM-4 and MEDICI simulators, and then the results were compared. It was observed from the simulation results that deep submicron elevated S/D NMOSFETs having shallower junction depth resulted in reduced short channel effects, such as DIBL, SS, and hot carrier effects than conventional NMOSFETs. The saturation current, Idsat, of the elevated S/D NMOSFETs was higher than conventional NMOSFETs with identical device dimensions due to smaller sheet resistance in source/drain regions. However, the gate-to-drain capacitance increased in the elevated S/D MOSFETs compared with the conventional NMOSFETs because of increasing overlap area. Therefore, it is concluded that elevated S/D MOSFETs may result in better device characteristics including current drivability than conventional NMOSFETs, but there exists trade-off between device characteristics and fate-to-drain capacitance.

• Journal of Haehwa Medicine
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• v.14 no.1
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• pp.15-22
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• 2005

Source : sources used by Qianghuo is Ostericum koreanum Maximowicz, Notopterygium incisum Ting and Notopterygium forbesii Boissier etc. in Korea and China. And we cirulate a Qianghuo dividing Nanqianghuo and Beiqianghuo. Thought source of Korea Qianghuo is different from china's we use a same name. And source of Beiqianghuo has not made clear yet. According to research accomplished 2002, we have to use Nanqianghuo producted at Jinbu in aspect of aspect. but, Beiqianghuo the outside form of Beiqianghuo similar to china so we think that we have to more make clear source of domestic Qianghuo, verify a source Beiqianghuo and re-establish about effects and functions of domestic Qianghuos. Culture : A term of culture is an nearly one year. so to product Qianghuo of good quality, we must plant directly in autumn or raise seedlings and transplant in spring. Processing : To protect turning to brown, Qianghuo are cirulate mostly as the original form without washing in water, To proteet crushing of Qianghuo when we cut off, Qianghuo were cut off after being soaked in water or steamed by heat. So when we wash and cut off, it has to be made processes which have no decreases of medical effects and be suggested a proper index which verify a medical effects. In summury, after harvesting Qianghuo the first washing $\rightarrow$ the first dry $\rightarrow$ selection $\rightarrow$ the second washing $\rightarrow$ the second dry $\rightarrow$ selection $\rightarrow$ cutting off $\rightarrow$ the third dry.

• The Research Journal of the Costume Culture
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• v.29 no.4
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• pp.554-571
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• 2021

The purpose of this study is to investigate the mediating effect of trust when a media broadcaster (such as a disc jockey [DJ]) acting as an information source and the content they provide during live commerce streaming affect acceptance intention. Live commerce is increasing rapidly, offering a new fashion distribution channel by supplementing possible shortcomings of existing online shopping. Data was collected for the empirical study from female consumers in their 20s who actively accepted fashion technology. Statistical analysis of the data was conducted using IBM SPSS Macro Process 3.5. First, the reliability and validity of the variables for information source characteristics, content informativeness, trust, and acceptance intention were verified, and each variable was confirmed as a single factor. Bootstrap analysis was performed using Macro Process Model 4 to reveal the effects of information source characteristics and content informativeness on acceptance intention. As a result of analyzing the mediating effect for each path model with trust as a parameter, it was found that both the direct and indirect effects of the mediating path were significant. This result means that the characteristics of information sources and content informativeness are partially mediated by trust. Therefore, to promote consumer behavior in a live commerce shopping environment, it is necessary to enhance trust. This can be achieved by a media broadcaster with fashion expertise to increase the perception of the attractiveness of the information source and to improve the usefulness of the fashion information being delivered.

• Journal of Fashion Business
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• v.26 no.4
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• pp.52-63
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• 2022

As live commerce, mobile sales platforms based on real-time content and text are drawing attention as a new marketing channel. In particular, the fashion industry also using live commerce as a new fashion distribution channel, requiring marketing strategies to utilize it efficiently. This study attempted to verify the effect of information source, sales promotion, and impulse buying tendency characteristics on fashion live commerce purchase intention. The experimental design of this study was 2(characteristics of information source: expertise vs attractiveness) × 2(sales promotion type: value-added vs price discount) × 2(impulse buying tendency: high vs low) three-way mixed analysis of variance(ANOVA). A convenience sampling of 264 women in their 20s and 50s living in Seoul and the Gyeonggi area who had purchased products through Live Commerce was conducted. For the final analysis, 240 questionnaires were used. Data were analyzed by the SPSS 26 program and three-way ANOVA. Simple main effects analysis was conducted. The results of this study follow. First, there were statistically significant differences in purchase intention according to consumers' impulse buying tendencies and sales promotions. Second, information source and sales promotion showed statistically significant interaction effects on purchase intention. Lastly, information source, sales promotion, and impulse buying tendency showed significant three-way interaction effects on fashion live commerce purchase intention. Therefore, conducting appropriate marketing analysis can result in positive attitudes regarding live commerce products and substantive increases in sales.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.4
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• pp.223-231
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• 2015

Enclosures are widely used to alleviate the contribution of machinery noise. It has been long concerned with the noise transmission through the access openings of the enclosures. In this study, we investigate active noise control technology for reduction of the transmission. A numerical model based on the acoustic boundary element method is first established. Using the numerical model, the acoustic transfer functions of the field points over the opening to the primary source at arbitrary locations are estimated. The feedforward control to minimize the acoustic power through the opening is then numerically implemented. The controller drives the secondary source to destructively interfere the noise transmission through the opening. Finally, a parametric study is conducted to evaluate the effects of the location and the number of the microphones on the control performance. Furthermore, the effects of the location of the secondary source on the performance of active noise control are investigated. It is followed that the control system implemented in this study leads to a significant reduction of about 31.5 dB in the sound power through the opening using only one secondary source located at the optimized position.

• The Journal of the Acoustical Society of Korea
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• v.16 no.6
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• pp.100-105
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• 1997

To analyze the multipath propagation effects on the source bearing detection of HLA(Horizontal Line Array), the conversion mechanism of the multipath into the bearing is described, and the bearing is estimated from the multipath modeled with typical sound velocity structures of the East and the South Sea of Korea. The erroneous bearing is observed from the beamforming outputs simulated with the modeled multipath, and the erroneous phenomena are analyzed. In case of the East Sea, since the multipath propagation with a high receiving angle occurs due to strong inverse slope of the sound velocity structure, it is possible that the estimated source bearing is different from the real source bearing, and that the number of the source is misrecognized.