• KIEAE Journal
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• v.15 no.3
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• pp.43-48
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• 2015

Purpose: Recently, many countries around the world are actively looking for the ways to make full use of natural energy sources and also develop and apply an environmentally friendly system designed to save building energy consumption. Under these circumstances, this study intended to determine the applicability and energy saving effect by deriving the indoor thermal performance characteristics and the PCM temperature appropriate for a double skin façade to reduce indoor energy consumption through the application of different PCM temperatures to double skin façade and perform a performance evaluation depending on the application or non-application of PCM to a double skin façade. Method: For this study, the physical variables of the double skin façade with PCM were configured through a preliminary examination based on an experimental measurement, and experimental measurements were taken with a total of 7 types of mockup cases: Type-1 (Basic), the basic double skin façade, Type-2 (PCM $18^{\circ}C$) which was applied to the inner skin of the double skin façade depending on the phase-change temperature of PCM, Type-3 (PCM $20^{\circ}C$), Type-4 (PCM $22^{\circ}C$), Type-5 (PCM $24^{\circ}C$), Type-6 (PCM $26^{\circ}C$), and Type-7 (PCM $28^{\circ}C$) with reference to the data analysis of the basic double skin façade which preceded this study, to analyze the indoor thermal performance of the double skin façade depending on PCM temperature and the installation or non-installation of a double skin façade applying PCM based on the selected unit space. Result: Indoor thermal performance was analyzed depending on the PCM temperature applicable to double skin façade, and the analysis of heating energy reduction showed that Type-2 (PCM $18^{\circ}C$) gained 15.9% more heat compared with Type-1 (Basic) and secondly, Type-3 (PCM $20^{\circ}C$) gained 11.5% more heat. Based on these findings, it is deemed possible that the use of energy for heating can be reduced when heat coming indoors increases during the heating period, and the appropriate temperature for PCM applied to the inner skin of a double skin façade to reduce heating energy in winter, Type-2 (PCM $18^{\circ}C$) showed the highest efficiency and Type-3 (PCM $20^{\circ}C$) was also deemed appropriate.

• Archives of Plastic Surgery
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• v.50 no.2
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• pp.142-147
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• 2023

Some of Asian eyelids have double fold and some do not. Many people tend to prefer double eyelid in aesthetic and functional reasons. Since the mechanism of double eyelid is bonding the eyelid skin to the eye-opening tissue, the principle of double eyelid surgery is also connecting the eyelid skin to levator component. Double eyelids are differentiated by their shape according to the height and curvature. The double eyelid surgery procedure is divided into incision method and nonincision method. And the incision method is subdivided into double fold line design, skin and oculi muscle incision or excision, pretarsal or preaponeurotic soft tissue excision, fixation of posterior lamella to anterior lamella, and skin suture. The nonincision method is to connect the posterior lamella and the anterior lamella as a thread only without an incision. A successful double eyelid surgery creates a fold well-balanced in height, curvature, and depth of the fold based on patient's preference. In this article, the author's own methods of performing surgery are described, with a step-by-step guide and surgical tips.

• Journal of the Korean housing association
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• v.14 no.3
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• pp.119-126
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• 2003

The purpose of this study is to evaluate the natural ventilation performance for variable external wind speed as a preliminary step to determining the seasonal operating modes of the Double-skin Facade System applied to apartment buildings. For this purpose, two simulation programs are used to compare the Double-Skin Facade System with the Double Sash Window. First, TAS is used to plan a schedule for natural ventilation during the intermediate season and to analyze the cooling loads. Second, CFD is used for a more detailed airflow analysis on a typical floor plan of the model building. The results of the simulations on natural ventilation performance show that the Double-Skin Facade System can reduce the cooling load by 10.5% compared to the Double Sash Window.

• KIEAE Journal
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• v.15 no.4
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• pp.29-35
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• 2015

Purpose: Double skin facade is a representative advantageous passive technology of building skin in the aspect of energy saving and environment improvement, reduces heat loss with buffer space in winter season and enhances indoor air and comfort of residents by activating natural ventilation in mid-season. However, in summer season, temperature increase in the intermediate space due to solar energy from exterior transparent skin could be a potential problem; also, relatively weak buoyancy of air caused by low density difference between double-skin facade could increase cooling load as air of intermediate space in high temperature hangs. However, proof data is insufficient to objectify such phenomenon. Method: In this study, researchers surveyed air temperature of intermediate space and airflow and diagnosed its cause targeting on applied multistory facade in the building which gives thermal uncomfort to residents. Also, the researchers produced Solar-air heat transfer coefficient meter, measured thermal boundary condition of double-skin facade, and presented the result of measurement as an objectified verification material regarding overheating phenomenon in the intermediate space of double-skin facade in summer season. Result: Inefficient condition was verified that total heat increases and overheating due to insufficient natural ventilation in multistory facade. In addition, logic behind preceding research was objectified and verified regarding high temperature phenomenon in the intermediate space which could increase cooling load in summer season.

• Fire Science and Engineering
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• v.23 no.5
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• pp.110-116
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• 2009

This study is related with fire risk assessment for fire and smoke spread of double skin facade system by use of FDS (Fire Dynamics Simulator) which is a computational fluid dynamics (CFD) model of fire-driven fluid flow. For the study, fire scenario is intended to evaluate the impact of a fire spread for glazed office building. The major purpose of this study is to analyze the fire risk depending on the width of between inner skin and outer skin and to present fire prevention method regarding double skin facade system. The result of analysis presents fire spread more vertically as intermediate space becomes narrow. It is anticipated that fire can spread upper 2 stories above the fire floor if intermediate space with not more than 1m width. Therefore, prevention of vertical fire spread is required.

• Journal of the Korean housing association
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• v.15 no.2
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• pp.11-18
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• 2004

The purpose of this study is to evaluate the sound insulation performance and present fundamental data for sound insulation plan about open and close windows of inner facade and outer facade of Double-skin Facade system applied to multi-story type. The Headquarter of Green Building and the Energy Saving Building in the Korea Institute of Energy Research was selected for experiment. Measurement method which are specified in the Korea Standard 2235 were selected for this study. As the result of this study, 1) Sound insulation performance of Multi-layer type of Double-skin Facades is very excellent about outdoor noise. 2) Vertical level is higher, it shows that more decreases sound pressure level.

• KIEAE Journal
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• v.17 no.1
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• pp.69-75
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• 2017

Purpose: Heat transfer analysis of recently developed 'slim type double-skin system window' were presented. This window system is designed for curtain wall type façade that main energy loss factor of recent elegant buildings. And the double skin system is the dual window system integrated with inner shading component, enclosed gap space made by two windows when both windows were closed and shading component effectively reflect and terminate solar radiation from outdoor. Usually double-skin system requires much more space than normal window systems but this development has limited by 270mm, facilitated for curtain wall façade buildings. In this study, we estimated thermophysical phenomena of our double-skin curtain wall system window with solar load conditions at the summer season. Method: A fully 3-Dimentional analysis adopted for flow and convective and radiative heat transfer. The commercial CFD package were used to model the surface to surface radiation for opaque solid region of windows' frame, transparent glass, fluid region at inside of double-skin and indoor/outdoor environments. Result: Steep angle of solar incident occur at solar summer conditions. And this steep solar ray cause direct heat absorption from outside of frame surface rather than transmitted through the glass. Moreover, reflection effect of shading unit inside at the double-skin window system was nearly disappeared because of solar incident angle. With this circumstances, double-skin window system effectively cuts the heat transfer from outdoor to indoor due to separation of air space between outdoor and indoor with inner space of double-skin window system.

• KIEAE Journal
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• v.8 no.1
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• pp.11-18
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• 2008

The purpose of this study is to analyze application methods and structural characteristics of each element of environment-friendly European housing through classification of skin types. The results of the study are following. 1) The skins are classified by three types; single skin with multi layers, double skin with single layer and double skin with multi layers. 2) Most single skins with multi-layer are composed with wooden louvers, sun blinds and insulating windows. There are introduction of atrium and balcony, and variation sectional space composition according to cases. 3) There are two types of double skins; to put cavity between inner skin and outer skin and more extensional spaces such as balconies, corridors and stair halls. Solar walls and mechanical ventilators are often introduced to double skins with multi-layer. 4) The functions of the latest environment-friendly skins are vary from controllers and buffers of indoor environmental elements such as temperature, light, air and sound to equipments to perform essential functions to efficiently operate HVAC systems.

• Journal of the Korean Solar Energy Society
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• v.30 no.5
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• pp.32-37
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• 2010

In order to handle the crisis about energy-environment problem, it is necessary to develop the future-oriented and innovative energy technology in architecture area. So the development of new technology for energy saving and alternative energy use has been spurred in this area. Double skin window system, which is an active covering to respond to the exterior change of the environment, is the skill that can reduce the indoor cooling and heating load and the environmental architecture can be realized. This study works out U-value of windows using the window-simulation program with the development and study of the double skin. In addition, the effect of the double skin insulation on the efficiency rating has been analyzed, applying to the certification system of the building energy efficiency rating which has implemented.

• Korean Journal of Human Ecology
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• v.12 no.2
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• pp.253-263
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• 2003

The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.