• Journal of the Semiconductor & Display Technology
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• v.15 no.2
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• pp.6-10
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• 2016

In RF plasma processing, when the plasma is generated, there is the difference of impedance between RF generator and plasma source. Its difference is normally reduced by using the matcher and the RF power is transferred efficiently from the power generator to the plasma source. The generated plasma has source impedance that it can be changed during processing by pressure, frequency, density and so on. If the range of source impedance excesses the matching range of the matcher, it cannot match all value of the impedance. In this research, we studied the elevation mechanism of the RF power delivery efficiency between RF generator to the plasma source by using the transmission line and impedance tuning of the plasma source. We focus on two plasma sources (capacitive coupled plasma (CCP), inductive coupled plasma (ICP)) which is most widely used in industry recently.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.617-624
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• 2010

Line heating is a manufacture method, which was widely used to machining a curved surface in the ship construction. The qualities using by line heating are very difference compare to the proficiency level of the engineer. So it's mainly depend on the automation equipment instead of the proficiency level engineer. In this study, it would be investigate the temperature distribution of the heating plate, which was used by the automation equipment according to line heating. The main factors are the moving velocity of the heating source, strength and the heating method separately, in temperature distribution while line heating. In this paper, it was investigated the temperature change with the vary of each three variables. The numerical result showed that peak temperature decrease if the moving velocity of the heating source increased. It can also calculate the change quantitatively that the peak temperature and temperature distribution changed linearly with the vary of the heating source.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.1
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• pp.1-7
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• 2020

Directivity control technology of sound system is a key technology for improving sound quality. Providing a line source rather than a point source in an acoustic system can reduce the effects of attenuation interference at long distances, thereby providing high quality sound. In particular, A line-array speaker system can be used to provide coherent, high-quality sound over long distances. However, high frequencies have shorter wavelengths, so the distance between the speakers of a line array system must be shorter, but there are physical limitations. In this paper, we designed a wave guide and installed it in the speaker's compression driver to solve this problem. We measured and tested various acoustic characteristics to verify the performance of the speaker. As a result, when the line array sound system is constructed using the developed speakers, it is possible to provide a line source in all areas including the treble range, thereby achieving the same effect as a single extended source and providing high quality sound up to far distances.

• Journal of Korean Society of Steel Construction
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• v.8 no.3 s.28
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• pp.97-105
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• 1996

A Stochastic line source model is developed to simulate the seismic wave field generated during the rupture propagation process along a fault plane of which length is much larger than its width. The fault plane is assumed to consist of randomly distributed slip zones and barriers and each slip zone is modeled as a point source. By combining the newly developed source model with wave propagation analysis method in a layered 3-D visco-elastic half space, synthetic seismograms are obtained. The calculated accelerograms due to vertical dip slip and strike slip line sources are presented.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.33-35
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• 2016

In this study, a new plasma source was used in the ALD process. Line type plasma sources were analyzed by electric and magnetic field simulation. And the results were compared with plasma density and electron temperature measurement results. As a result, the results of the computer simulation and the diagnosis results of plasma density and electron temperature showed similar tendency. At this time, the plasma uniformity is 95.6 %. $Al_2O_3$ thin film was coated on 6 inch Si-wafer, using this plasma source. The uniformity of the thin film was more than 98% and the thin film growth rate was 0.13 nm/cycle.

• Journal of electromagnetic engineering and science
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• v.9 no.4
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• pp.175-181
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• 2009

The measurements were performed to verify experimentally that the voltage arising on a telecommunication line by a power line is due to the induction phenomena because there has been an opinion that the arising voltage on a telecommunication line is not by induction, but by other causality. The voltage appeared on the telecommunication line by way of an electric field or magnetic field generated by the source apparatus that had been artificially made to provide intentional constant high-voltage or current in ELF, that is, 60 Hz as an emulated commercial power.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.1112-1115
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• 2004

Recently, KTX start service 2004 and speed up the Chung-ang line and Ho-nam line using tilting train. When the train speed up at curve the vibration environment are changed. It is the reason of the wave propagation problem in the curved source. In this research, using SSI Program SASSI, Predict the vibration propagation around the curved source of vibration. The curved source of vibration propagation is different from straight source of vibration propagation. In this study, made a curved vibration source model and compared with straight model.

• Journal of Distribution Science
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• v.14 no.11
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• pp.117-128
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• 2016

Purpose - In order to collect information needed for the establishment of more effective marketing strategies of on-line purchasing agent services targeting Chinese consumers, the study investigated the relationship among Chinese selection criteria. They included fashion products, use of information source, and satisfaction with on-line purchasing agent services. The study also identified the differences in the Chinese selection criteria of fashion products, use of information source, and the satisfaction level with on-line purchasing agent services according to their age and gender. Research design, data, and methodology - The study was implemented through a normative-descriptive survey method using a self-administered questionnaire. Data were collected from February 9 to 28, 2016, and analyzed by factor analysis, ANOVA and Duncan test, t-test, and multiple regression analysis. Results - Differences were found in selection criteria of fashion products and use of information sources among groups. Thirty's age group was concerned about price/brand more than the twenty's were. Twenty's were concerned about practicality/quality of the products more than the thirty's. Hallyu/broadcasting was used by men more than by women as an information source of Korean fashion. SNS/WOM(word of mouth) was used more by women than by man. Twenty's showed lower level of satisfaction with customer services/credibility than other factors. The thirty's showed lower level of satisfaction with informational role of the service than other factors. Those who utilize each type of fashion information source more showed higher satisfaction level with on-line purchasing agent service of Korean fashion products.. In general, according to the selection criteria and use of information, there were differences in satisfaction with on-line purchasing agent service of Korean fashion products. Conclusions - Considering the findings of the study, as well as age, gender, selection criteria and use of information source, Chinese consumers could be used as a criteria of market segmentation for on-line purchasing agent services of Korean fashion products. The results manifested that there is a need to differentiate marketing strategies according to the satisfaction levels with each satisfaction factors of on-line purchasing agent service of Korean fashion products.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.5
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• pp.371-381
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• 2021

A machine vision inspection system consists of a camera, optics, illumination, and image acquisition system. Especially a scanning system has to be made to measure a large inspection area. Therefore, a machine vision line scan camera needs a line scan light source. A line scan light source should have a high light intensity and a uniform intensity distribution. In this paper, an offset calibration and slope calibration methods are introduced to obtain a uniform light intensity profile. Offset calibration method is to remove the deviation of light intensity among channels through adding intensity difference. Slope calibration is to remove variation of light intensity slope according to the control step among channels through multiplying slope difference. We can obtain an improved light intensity profile through applying offset and slope calibration simultaneously. The proposed method can help to obtain clearer image with a high precision in a machine vision inspection system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.10
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• pp.453-459
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• 2014

This paper presents an analysis on the initial ignoring time of SCW type GHX using Mean Square Error method. Line source method is a useful method for estimating the ground thermal conductivity for the vertical type and SCW type GHX in Korea. The line source method for ground thermal conductivity of geothermal in-site test is the basis of linear approximation between the temperature of a borehole and logarithmic time in a GHX. To apply the line source method to the estimation of SCW type GHX, it is necessary to ignore the initial time of data at the stage of a linear approximation. This paper proposed a new initial ignoring time of SCW type GHX among various initial ignoring time at the time for reaching MSE of $0.02^{\circ}C^2$.