• KIEAE Journal
• /
• v.15 no.5
• /
• pp.75-82
• /
• 2015

Purpose: The first grade of Korea's Building Energy Efficiency Rating System(BEERS) is required for new government office buildings as a mandatory measure to reduce greenhouse gas emission. However, there is no specific criteria about performance that which level should apply to energy-saving design element for obtaining Building Energy Efficiency Rating 1st grade. Therefore, Certification status should be analyzed firstly, about the office building which is certificated. Certification analysis for office buildings acquired certification therefore should be done first. Method: In this study, Certification status(Office buildings acquired Building Energy Efficiency Rating Certification)was analyzed by classified year, region, specific scale etc. And we analyzed statistically by eliciting an average value of each element influencing to the amount of energy. Result: Energy demands were gradually decreased due to revision of thermal insulation standards for enhanced u-value. Energy consumptions were different from the kind of equipment and yearly trends applied depending on the size of the building. Total primary energy consumptions were influenced by heat source types and the primary energy scale factors.

• KIEAE Journal
• /
• v.17 no.3
• /
• pp.45-50
• /
• 2017

Purpose: There have been more researches focused on eco-friendly construction practices in order to save energy consumed and these practices have been extensively applied for constructing buildings. However, researches on energy consumption saving and efficiency for hospital facilities have been still insufficient. This research aims to draw factors that affect energy efficiency of hospital buildings through literature reviews and perform an expert-survey using AHP(Analytical Hierarchy Process) method in order to analyze the importances and priorities of these energy efficient factors. Method: Using the AHP method, this paper suggests the importances and priorities of factors to affect energy efficiency in hospital buildings. The survey of experts at a architectural design and a construction management companies was conducted via e-mail and mail. Result: As a result, factors of window and door, insulation, ventilation, and natural lighting turned out relatively important as respectively 0.104, 0.102, 0.101, and 0.095 n the energy efficiency in hospital buildings, while factors of artificial lighting, geothermal, solar heat, and control did unimportant as 0.027, 0.033, 0.043, and 0.053.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2011.04a
• /
• pp.526-531
• /
• 2011

A dash panel component, close to passengers, plays a very important role to protect heat and noise from a power train. Meanwhile, it is also a main path that transfers vibration energy and eventually radiates acoustic noise into the cavity. Therefore, it seems important to provide an optimal design scheme incorporating sound packages such as dash isolation pad and carpet, as well as structures. The present study is the extension of the previous investigation how design variables affect sound radiation, which was carried out using the simple plate and framed system. The system taken into account in this paper is a dash panel component of a sedan, which includes A pillar, front side member, dash panel and the corresponding sound packages. Design variables such as panel thickness and sound package layers are investigated how they are related for the better radiation performance (i.e. structure-borne) and sound transmission loss (i.e. air borne).

• Fire Science and Engineering
• /
• v.23 no.1
• /
• pp.33-39
• /
• 2009

In this study, the combustion properties, which are called the reaction-to-fire's performance, of sandwich panels were tested and analyzed according to both ISO 5660 (cone calorimeter method) and EN 13823 (SBI). Several variables including ignition time, mass loss, heat release rate, smoke production rate and $O_2$ density about four sandwich panels and four core materials (thermal insulation material) were evaluated. Combustion properties' similarity and difference of sandwich panels and core materials were compared by materials and test methods respectively. Finally test results were evaluated by Japanese standard building code, National Building code of Canada and EN 13501-1 as well.

• Journal of Sensor Science and Technology
• /
• v.15 no.1
• /
• pp.53-57
• /
• 2006

This paper describes a novel processing technique for fabrication of polymer-derived SiCN (silicone carbonitride) microstructures for super-temperature MEMS applications. PDMS (polydimethylsiloxane) mold is fabricated on SU-8 photoresist using standard UV photolithographic process. Liquid precursor is injected into the PDMS mold. Finally, solid polymer structure is cross-linked using HIP (hot isostatic pressure) at $400^{\circ}C$, 205 bar. Optimum pyrolysis and annealing conditions are determined to form a ceramic microstructure capable of withstanding over $1400^{\circ}C$. The fabricated SiCN ceramic microstructure has excellent characteristics, such as shear strength (15.2 N), insulation resistance ($2.163{\times}10^{14}{\Omega}$) and BDV (min. 1.2 kV) under optimum process condition. These fabricated SiCN ceramic microstructures have greater electric and physical characteristics than bulk Si wafer. The fabricated SiCN microstructures would be applied for supertemperature MEMS applications such as heat exchanger and combustion chamber.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.18 no.2
• /
• pp.273-282
• /
• 1994

The physiological significances of the upper and lower body on thermoregulation and sensation were studied in this paper. Experiments were carried out on 4 females in a climatic chamber conditioned at 1) $25^{\circ}C\rightarrow35^{\circ}C\rightarrow25^{\circ}C$, 2) $25^{\circ}C\rightarrow15^{\circ}C\rightarrow25^{\circ}C$, both with 50% R.H., covering the upper body (U) or lower body (L) with garments. 1. When the upper or lower body is covered or exposured respectively, the mean skin tempterature of upper body is higher than that of lower body. And upper body is more easily influenced by the environmental temperature than lower body. It means the skin temperatures of the upper body change faster than those of the lower body following the environmental changes. 2. In U and L, the skin temperatures of the upper limbs (thighs, upper arms) are lower than those of the peripherals (hands, feet). 3. Warm sensations and skin temperatures of the upper body showed high correlation and it was the case with cold sensations and skin temperatures of the lower body. 4. In high temperature condition $(25^{\circ}C\rightarrow35^{\circ}C\rightarrow25^{\circ}C)$, mean skill temperature and rectal temperature in L were lower than in U. This lower rectal temperature in L is probably due to the insulation of the lower body with garments that promotes the heat radiation only in the high temperature environment.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2012.11a
• /
• pp.179-180
• /
• 2012

Aluminum alloys are widely known as non-ferrous metal with light weight and high strength. Consequently, these materials take center stage in the aircraft and automobile industry. The Al7075 aluminum alloy is based on the Al-Zn-Mg-Cu and one of the strongest wrought aluminum alloys. Aluminum nitride has ten times higher thermal conductivity($319W/m{\cdot}K$) than Al2O3 and also has outstanding electric insulation($1{\times}1014{\Omega}{\cdot}cm$). Furthermore, it has high mechanical property (430 MPa) even though its co-efficient of thermal expansion is less than alumina For these reasons, it has great possibilities to be used for not only the field which needs high strength lightweight but also electronic material field because of its suitability to be applied to the insulator film of PCB or wafer of ceramic with high heat conduction. This paper investigates the mechanical properties and corrosion behavior of aluminum alloy Al7075 deposited with aluminum nitride thin films To improve the surface properties of Al7075 with respect to hardness, and resistance to corrosion, aluminum nitride thin films have been deposited by pulsed DC reactive magnetron sputtering. The pulsed DC power provides arc-free deposition of insulating films.

• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2274-2276
• /
• 1999

In this work, temperature rise and eddy current distribution on the enclosure and conductor of 3 pole gas insulated switchgear were investigated using analytical and experimental measures. The design of the diameters of the conductors and the enclosures of a meal clad gas insulated switchgear is primarily based on the insulation requirements. It is very difficult problem to predict the temperature rise of enclosed switchgear due to the complexity of the phenomena of heat transfer and existence of eddy current loss. To overcome this situations, we focused on the eddy current distribution on the enclosure of switchgear caused by high current 3 pole conductor as a fundamental basis. The experimental results about temperature distribution of 3 pole gas insulated switchgear were reported and measurements are compared with predictions of three-dimensional thermal model for eddy current analysis. As a result, three dimensional numerical analysis found to be in close relationship with experimental results and thermal model is efficient to predict the abnormal temperature rise in switchgear.

• Korean Journal of Materials Research
• /
• v.27 no.7
• /
• pp.353-358
• /
• 2017

Recycled cenosphere, which is a hollow shaped particle from fly ash, has become attractive as a building material due to its light weight and excellent heat insulation and soundproof properties. In this paper, we investigated the effect of cenosphere size on the physical and optical properties. High brightness of cenosphere as raw material is required for a wide range of ceramics applications, particularly in fields of building materials and industrial ceramic tiles. Cenospheres were sorted by particle size; the microstructure was analyzed according to the cenosphere size distribution. Cenospheres were generally composed of quartz, mullite, and amorphous phase. Colour measurement corresponding to chemical composition revealed that the contents of iron oxide and carbon in the cenospheres were the major factors determining the brightness of the cenospheres.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.8 no.2
• /
• pp.27-35
• /
• 2012

Five zero energy house models developed in Korea for the purpose of the energy performance were compared and analyzed in the study. The standard passive house model applying common technology and efficient energy performance elements was proposed. Standard passive house 5 models have been developed commonly aiming at 100% energy saving, applying high-performance and high-efficiency exterior thermal insulation, using 3 low-e coated window system, and targeting average 0.65 ACH to enhance privacy. Energy recovery ventilators and dry and cold radiant heating floor has been partially applied. Eco-design techniques such as the awning device, heat insulating door, using natural light have been used. Solar and geothermal systems as the application of renewable energy technologies have been commonly applied. And fuel cells were applied to a partial model. The standard model based on common technical elements and average performance of each element and obtained from five model analysis has been proposed in the study.