• KIEAE Journal
• /
• v.17 no.5
• /
• pp.77-86
• /
• 2017

Purpose: Because of the growing concern over fossil fuel use and increasing demand for greenhouse gas emission reduction since the 1990s, the building energy analysis field has produced various types of methods, which are being applied more often and broadly than ever. A lot of research products have been actively proposed in the area of the building energy simulation for over 50 years around the world. However, in the last 20 years, there have been only a few research cases where the trend of building energy analysis is examined, estimated or compared. This research aims to investigate a trend of the building energy analysis by focusing on methodology and characteristics of each method. Method: The research papers addressing the building energy analysis are classified into two types of method: engineering analysis and algorithm estimation. Especially, EPG(Energy Performance Gap), which is the limit both for the existing engineering method and the single algorithm-based estimation method, results from comparing data of two different levels- in other words, real time data and simulation data. Result: When one or more ensemble algorithms are used, more accurate estimations of energy consumption and performance are produced, and thereby improving the problem of energy performance gap.

• Proceedings of the Korean Nuclear Society Conference
• /
• 2005.10a
• /
• pp.518-519
• /
• 2005

• Journal of the Korean Society for Nondestructive Testing
• /
• v.33 no.2
• /
• pp.212-218
• /
• 2013

A transfer method of neutron radiography was developed to measure the size of the end plug and a gap of an intact K102L-2, the irradiated fuel of a ballooned K174L-3, a ballooned and ruptured K98L-3. A typical irradiation time of 25 min. was determined to obtain a film density of between 2 and 3 of SR X-ray film with neutrons of $1.5{\times}10^{11}n{\cdot}cm^{-2}$. To validate and calibrate the results, a RISO fuel standard sample, Cd plate and ASTM-BPI/SI were used. An activated latent image formed in the $100{\mu}m$ Dy foil was subsequently transferred in a dark room for more than 8 hours to the SR film which is a maximum of three half-lives. Due to the L/D ratio an unsharpness of $9.82-14{\mu}m$ and a magnification of 1.0003 were given. After digitizing an image of SR film, the ballooning gap of the plug was discernible by an H/V filter of image processing. The gap size of the ballooned element, K174L-3, is equal to or greater than 1.2 mm. The development of a transfer method played a pivotal role in developing high burn-up of Wolsung and PWR nuclear fuel type.

• Nuclear industry
• /
• v.28 no.10
• /
• pp.55-63
• /
• 2008

• Journal of Power System Engineering
• /
• v.20 no.6
• /
• pp.99-104
• /
• 2016

In this study, we researched the energy load according to the change of the inner window area ratio, the distance of the air gap and the azimuth of the curtain wall building, which installed the multistory double-skin facade(DSF). and we compared the results with the no double-skin facade situation as follows. With the DSF, it is better than other case, when the window area ratio is 40% and the air gap is 1.2m on the west, south-45-west, south-45-east and east. And it's best when the window area ratio is 40% and the air gap is 0.4m on the south. And on the east or south-45-east, the window area ratio is 40% and the air gap is 1.2m is better than other case with the DSF. On south, it is best when the window area ratio is 100% without DSF. On the south-45-west or west, it is best when the window area ratio is 40% without the DSF.

• Journal of the Korean Vacuum Society
• /
• v.2 no.2
• /
• pp.220-226
• /
• 1993

An investigation was made of the dependences of the lattice constants and the energy gap on the composition of $TlGa_xIn_{1-x}Se_2$ single cystals grown by Bridgman method. It was found that a discontinuity in $TlGa_xIn_{1-x}Se_2$ solid solutions occurred in the composition range 0.25$0.0{\leq}X{\leq}0.25$) to the monoclinic structure ($0.65{\leq}X{\leq}1.0$) was observed in this composition range. The temperature dependences of the energy gap and the dielectric constant in $TlGaSe_2$ single crystal have shown that the anomalies appeared at 107 K and 120 K corresponding to first-order and second-order phase transitions, respectively.

• Journal of Energy Engineering
• /
• v.1 no.1
• /
• pp.66-75
• /
• 1992

The performance of heat transfer through double pane window has been investigated using experimental and numerical methods. The range of the gap distance between glasses are 0.5-10 cm. The convection heat transfer plays the dominant role for the case of the wide gap distance together with the large Rayleigh number and thereby, reduces the enhanced thermal resistance due to the increased air gap, while the conduction heat transfer does the major role for the case of small gap distance. In order to enhance the thermal insulation of the double pane window, the heat transfer of triple pane window, which is constructed to put one more glass at the middle of the double pane, is investigated to check the reduction of the convection heat transfer together with the effect of the radiation shield due to the presence of the additional glass. Further, a spacer is installed at the middle height of the double pane, and the effect of which on the suppression of the convective heat transfer is analyzed carefully, using experimental and numerical methods. For the case of the spacer-installation, the amount of energy saving is considered about 10%, but the energy saving increases a lot to 30-50% for the case of triple pane window, due to the substantial radiation shield effect of the presence of the additional glass.

• Journal of the Korean Vacuum Society
• /
• v.1 no.2
• /
• pp.244-253
• /
• 1992

BiSI, BiSI : Co, BiSeI 및 BiSeI : Co 단결정을 고순도의 성분원소와 8.6mole% 과잉의 Iodine를 투명석영관내에 넣고 진공봉입하여 합성한 ingot를 사용하여 수직 Bridgman 방법으로 성장시켰다. 성장된 단결정은 orthorhombic 구조였고, energy band 구 조는 간접전이형으로 293K에서 광학적 energy gap은 각각 1.590eV, 1.412eV, 1.282eV 및 1.249eV로 주어지며, energy gap의 온도의존성은 Varshni 방정식으로 잘 표현된다. Cobalt 를 첨가할 때 나타나는 불순물 광흡수 peak는 Td symmetry점에 위치한 Co2+, Co3+ ion의 energy 준위들 사이의 전자전이에 의해서 나타난다.

• Journal of the Korean Vacuum Society
• /
• v.3 no.2
• /
• pp.239-246
• /
• 1994

Cd1-xCoxIn2Se4($\chi$=0.000, 0.001, 0.005, 0.10, 0.50) 단결정을 수직 Bridgman 방법으로 성장시키고 성장된 단결정의 조성 및 결정구조를 조사하고 광학적 특성을 연구하였다. 성장된 단결정은 pesudocubic 구조이고 격자상수는 조성$\chi$가 증가함에 따라 약간씩 감소하였다. 기초 흡수단 영역에서의 광흡수 spectra 측정에서 이 단결정들은 간접전이 및 직접전이 및 직접전이 energy gap을 갖고 있으며 이들 energy gap의 조성의존성은 조성이 $\chi$=0.00에서 $\chi$=0.016까지는 기울기가 같고 $\chi$=0.016에서 기울 기가 변화되어서 $\chi$=0.016에서 $\chi$=0.50까지는 같은 기울기를 갖고 있다. 이러한 현상은 $\chi$=0.016에서부터 CdIn2Se4 내에 cobalt를 포함한 새로운 물질이 형성되고 이 물질과 a-CdIn2Se4 사이에 고체고용체를 형 성하기 때문이다.

• Journal of Korea Foundry Society
• /
• v.20 no.2
• /
• pp.80-88
• /
• 2000

Continuous casting equipment was designed to cast the metallic uranium rods, and a thermal analysis was carried out to calculate the temperature and solidification profiles. Fluid flow and heat transfer analysis model including the effects of phase change was used to simulate the continuous casting process by finite volume method. In the design of continuous casting equipment, the casting speed, pouring temperature and cooling conditions should be considered as significant factors. In this study, the effects of casting speed, pouring temperature, and air gap between the uranium and mold were investigate. The results represented that the temperature and solidification profiles of continuous casting equipment varied with the casting speed, pouring temperature, and air gap.