• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.193-198
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• 2005

The present experiments have been performed for obtaining the melting heat transfer characteristics of micro-encapsulated solid-liquid phase change material and water mixed slurry flow in a circular tube heated with constant wall heat flux. The phase change material having a low melting point was selected for a domestic cooling system in the present study. The governing parameters were found to be latent heat material concentration, heat flux, and the slurry velocity. The experimental results revealed that the increase of tube wall temperature of latent microcapsule slurry was lower than that of water caused by the heat absorption of fusion.

• 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.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.6
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• pp.518-525
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• 2006

The present experiments have been performed for obtaining the melting heat transfer characteristics of micro-encapsulated solid-liquid phase-change material and water mixture slurry flow in a circular tube heated with constant wall heat flux. The phase change material having a low melting point was selected for a domestic cooling system in the present study. The governing parameters were found to be latent heat material concentration, heat flux, and the slurry velocity. The experimental results revealed that the increase of tube wall temperature of latent microcapsule slurry was lower than that of water caused by the heat absorption of fusion.

• Korean Journal of Human Ecology
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• v.20 no.2
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• pp.285-298
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• 2011

The purpose of this study was to analyze in detail the employment characteristics of the elderly over 65 years old and to compare those that have experienced no job change in the last 10 years with another group that have experienced job change at least once in the last 10 years. From the 10th wave data(KLIP), participants who were over 65 years old were chosen and their employment status for the last 10 years was reviewed. The results of this study were as follows: first, the analysis of demographic profiles indicated that householders and elderly couples with low education levels and low socioeconomic status were more likely to be employed compared to others. Second, in terms of work-related characteristics, it was revealed that the elderly who were employed tended to be non-paid workers, employers, and self-employed workers, primarily in the farming, fishing, forestry, and the mining industries, these were the elderly workers who had experienced job change three times or more in the last 10 years. Third, the analysis of economic characteristics indicated that elderly who were employed tended to rely more on private income transfers. Last, when the elderly who had experienced no job change in the last 10 years were compared to the elderly who had experienced job change in the last 10 years, the two groups differed significantly in terms of employment status, type of business, and occupation category.

• Journal of Society of Preventive Korean Medicine
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• v.14 no.1
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• pp.1-12
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• 2010

This research was intended to delve into the diversity of life phenomenon and its characteristics. First of all, this research gave real examples to compare the differences in men's health, disease, and longevity in order to confirm the existence of diversity of life phenomenon. In addition, it also studied the process and mechanism of manifestation of life phenomenon, as well as the influence and problems of existing studies' results and implications. The results are as follow. 1. Differences in health, diseases, and longevity were very big and diverse in researches on different races, nations, ages, socioeconomic status, positions, and even (monozygotic) twins. 2. The basic foundation of all organisms is DNA, and environmental factors change DNA methylation and the structure of chromatin by constantly influencing DNA. Due to this, the manifestation, control, and phenotype of DNA change, resulting in diversified life phenomenon. Therefore, it is the environmental factors, not DNA, that has more influence on the diversity of life. 3. Looking at available studies, the most reasonable perspective on human requires focusing on the diversity of life phenomenon, holistic thinking, and reversible change instead of irreversible determinism. Considerable differences in life phenomenon between entities require a change in malformed perspective on life. Public health and medicine deals with live human beings, a more precise and accurate perspective on life is very important. Because management methods of health and disease, such as structure and approaches of medical research, prevention and cure, must be different by life perspectives.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.2
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• pp.27-38
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• 2008

This study aims to examine Japanese elementary school architecture in Meiji Era, in which Japanese modern education system was settled down and the school architecture flourished by mass construction of stereotyped school buildings. It is assumed that stereotyped school architecture is due to the influence of the standard drawings made by Japanese Ministry of Education, therefore standard drawings could be a key to understand the characteristics of the stereotyped school buildings in Meiji Era. In this perspective this study attempts to analyze 4 standard drawings and interpret it in relation to regulations and design guidelines for school architecture in that time. As results of this study the change and characteristics of stereotyped school architecture in Meiji Era are clarified in several categories. They are as follows : the deviation of classroom and corridor, the change of classroom size fixing to 4 kan(間) by 5 kan(間), the absolute use of north-lacing single corridor type block-plan, and the change of other space such as waiting room(控所), special instruction room, auditorium and gymnasium.

• Fire Science and Engineering
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• v.29 no.5
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• pp.57-66
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• 2015

This thesis is based on a research to investigate the electrical fire risk due to the single and composite cause in a terminal block. This paper analyzed the thermal characteristics depending on the screw torque change and contact resistance change to measure the fire risk due to the poor contact from single cause first. To measure the fire risk due to the composite cause, the acceleration tracking depending on the contact resistance change was experimented to check the correlation of poor contact and tracking to fire. The experiment result showed that the thermal characteristics were clearer as the screw torque in poor contact status and magnitude of contact resistance increased and that the thermal characteristics of terminal block depending on the contact resistance change was more reliable than the thermal characteristics depending on the screw torque change. Moreover, the terminal block poor contact and tracking were correlated in the case of the composite cause, and when two composite causes were interacted, the electrical fire risk was higher than the single cause.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.1
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• pp.70-74
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• 2004

We investigated transmittance, surface characteristics, and resistivity according to bending of ITO(indium tin oxide) film with four other multi -harrier film). Transmission data of ITO film with four ITO films showed there was about large 90％ transmission above 550nm wavelength at three multi-barrier structures. But, both-side hard coated structure showed relatively low 75％ transmission above 550nm wavelength. And, surface images measured from SEM (scanning electron microscope) showed both-side hard coated structure have a tendency of more roughness. Also, resistivity change of four other multi-barrier film showed there was the lowest change at one-side hardcoated structure. Subsequently, with result of resistivity change according to position, we knew the resistivity change of the center increased rapidly than that of the edge.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.05a
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• pp.385-388
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• 2007

In this paper approves AC high voltage by experimental GIS(Gas Insulated Switchgear) chamber and AC 300[kV] power source to study breakdown characteristics by pressure(P) change and change of electrode distance(d) at AC high voltage of Imitation Air(I-Air, $N_2$ : $O_2$ = 79[%] : 21[%]) to alternate $SF_6$ and achieved research. Gave P change of I-Air to study I-Air's breakdown characteristics using non-uniform fields(Needle--Plane electrode) and studied relations breakdown voltage ($V_B$) by each P different d.

• Journal of Broadcast Engineering
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• v.14 no.1
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• pp.81-84
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• 2009

This paper explores the possibility of describing objects from the change in the shape according to the change in viewpoint. Specifically, we sample the shapes from various viewpoints of a 3-D model, and apply dimension reduction by locally linear embedding. A low dimensional distribution of points are constructed, and characteristics of the object are described from this distribution. Also, we propose two 3-D retrieval methods by applying the iterative closest point algorithm, and by applying Fourier transform and measuring similarity by modified Housdorff distance, and present experimental results. The proposed method shows that the change of shape according to the change in viewpoint can describe the characteristics of an object.