• Journal of Advanced Marine Engineering and Technology
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• v.26 no.1
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• pp.23-29
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• 2002

Solid-liquid phase change (i.e. melting or solidification) occurs in a number of situations of practical interest. Some common examples include the melting of edible oil, metallurgical process such as casting and welding, and materials science applications such as crystal growth. Therefore, due to the practical importance of the subject, there have been a large number of experimental and numerical studies of problems involving phase change during the past few decades. Also, this study presented the effective way to enhance phase change heat transfer.

• International Journal of Quality Innovation
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• v.2 no.1
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• pp.30-49
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• 2001

This paper considers a recent environment in the manufacturing process in which data in large amounts can be obtained on-line in real-time. Under this environment an on-line real-time Statistical Process Control (SPC) scheme equipped with detection of a process change, change-point estimation, and recognition of the change pattern is proposed. The proposed SPC scheme is composed of a Cusum chart, filtering methods and Akaike Information Criterion (AIC). We examine the performance of this scheme by Monte Carlo simulation and show its usefulness.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1995.06a
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• pp.59-61
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• 1995

An adaptive code rate change scheme in DS-SSMA systems is proposed. In the proposed scheme, the error correcting code rate is changed according to the channel state, the effective number of users. The channel state is estimated based on retransmission requests. The criterion for the change of the code rate is to maximize the throughput under given error bound.

• Journal of The Korean Digital Architecture Interior Association
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• v.2 no.1
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• pp.1-8
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• 2002

Purpose of this study is studying direction that change of design by development of new digital technology. And with new technology, find direction of architectural design. Digital technology for architectural design demonstrates hightechnology or is not limit. Must recognize change for our idea and necessity. We can know change in relation of photography and impressionism. Idea and hitting on a thought which is arts by new technology changed. Finally, we must develop techniques of design on the basis of technology and look for possibility of new expression. Digital medium expands communication with designer and customer because there is special quality of nonlinearity, interactivity and audiovisuality unlike old medium. Digital medium can take advantage of techniques of new design. Can construct R&D and database of design and improve quality of design. Designer must master use skill to take advantage of digital technology in design. Because quality of design becomes different according to degree that use. Also, developer of digital technology must supply design tool such as previous design method. Creativity that architectural design that allow fetters in digital technology can understand design in new viewpoint is required. Architectural design may be magnified by architectural design that allow fetters in multimedia. We may see experience between new time and space of architectural design and reappearance space reappeared in cyberspace. Architect is going to run role as developer of culture. Value and technology of digital design may offer more more possibility and an opportunity since Intustrial-Revolution.

• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.154-163
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• 2017

Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. However, the head characteristics are different under different guide vane openings. In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings. Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. The results reveal that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic loss (power dissipation) in the guide and stay vanes. It is also found that the hydraulic loss mainly comes from the flow separation and vortices. In addition, in some operating conditions, the change of guide vane opening will change the flow angle at the runner inlet and outlet, which will change the Euler momentum (power input). The joint action of Euler momentum and hydraulic loss results in the change of the head characteristics.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.126-129
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• 2005

Change detections is carried out under the assumption that pixel boundaries of geometrically corrected time series satellite images cover the same location. However that assumption can be wrong when shifts in the pointing direction of a satellite sensor occurs. Currently, although the influence of misregistration on landcover change detection has been investigated, there has been little research on the influence of pointing direction shifts of a satellite sensor. In this study, a simple method for reducing the effects of pointing direction shifts of a satellite sensor is proposed: the classification of two ASTER images was carried out using the linear spectral mixture analysis, the two classification results were resampled into a geometrically fixed grid, and then the change detection of the two ASTER images was carried out by comparing the resampled classification results of the two images. The proposed method showed high performance in discriminating between changed areas and unchanged areas by removing the pointing direction shifts of a satellite sensor.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.6
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• pp.731-738
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• 2010

Cavitation is described by formation and collapse of the bubbles in a liquid when the ambient pressure decreases. Formed bubbles grow and collapse by change of pressure, and when they collapse, shockwave by high pressure is generated. In general, bubble behavior can be described by Rayleigh-Plesset equation under adiabatic or isothermal condition and hence, phase shift by the pressure change in a bubble cannot be considered in the equation. In our study, a numerical model is developed from the mathematical model considering the phase shift from the previous study. In the developed numerical model, size of single spherical bubble is calculated by the change of mass calculated from the change of the ambient pressure in a liquid. The developed numerical model is verified by a case of liquid flow in a narrow channel.

• International Journal of Advanced Culture Technology
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• v.7 no.3
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• pp.103-110
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• 2019

The purpose of this study was to investigate the relationship between psychosocial factors, such as self-esteem, stress coping, and social support, and motivation for change in alcohol dependent inpatients. This study included 179 inpatients in the 7clinics for alcoholic in Chonbuk. For the analysis of the study questions, this study utilized the structural equation modeling. The results show that self-esteem was related to motivation for change with mediating role of problem-focused stress coping strategy in alcohol dependent inpatients. The study also reveal that self-esteem and social support was directly associated with the motivation for change. Based on the findings, the importance of programs to promote self-esteem and the involvement of family and acquaintances in the treatment process has been suggested.

• Journal of Korea Technology Innovation Society
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• v.5 no.2
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• pp.189-211
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• 2002

The research shows how the technological change of 'Information and Communication Technology' (ICT) is accompanied with the usage change. It aims to provide a better conceptualization with empirical findings about the fact that the technological development of ICT is a convergence process of ICT factors with the usage of ICT moving from a limited coverage toward a general-purpose. The research adapts a descriptive methodology on a historical matter and demonstrates how it can be conducted through analytical description of Input-Output tables (I/O) the over periods. The case is about the UK with sequential I/O during 1970s- 90s.

• Journal of Broadcast Engineering
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• v.20 no.6
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• pp.871-879
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• 2015

With the increase of mass contents data, a method of a scene change detection is required for analysis, indexing and editing. Although many researchers are studying a variety of scene change detection method, it is too difficult to accurately detect various movements of the cameras and scene changes. Also, earlier scene change detection methods take too much time to apply to UHD video contents. That is because the UHD video contents with 4K (3820x2160) resolution or higher have greater amount of data. Therefore a method for detecting a scene change by using the next-generation codec, HEVC, is required. In this paper, we propose four scene change detection methods using the coding additional information of HEVC, and a new pixel-based scene change detection system. Furthermore, through the experimental results, we check the possibility of detecting the scene changes of UHD videos encoded in HEVC format.