• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.894-903
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• 2014

Insertion loss prediction of large acoustical enclosures using Statistical Energy Analysis (SEA) method is presented. The SEA model consists of three elements: sound field inside the enclosure, vibration energy of the enclosure panel, and sound field outside the enclosure. It is assumed that the space surrounding the enclosure is sufficiently large so that there is no energy flow from the outside to the wall panel or to air cavity inside the enclosure. The comparison of the predicted insertion loss to the measured data for typical large acoustical enclosures shows good agreements. It is found that if the critical frequency of the wall panel falls above the frequency region of interest, insertion loss is dominated by the sound transmission loss of the wall panel and averaged sound absorption coefficient inside the enclosure. However, if the critical frequency of the wall panel falls into the frequency region of interest, acoustic power from the sound radiation by the wall panel must be added to the acoustic power from transmission through the panel.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.11-16
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• 2005

This study is for the insulation construction of inner wall in a bathroom facing on the outside in the housings. This new dry construction method can be constructed by a dry panel which is bonded tiles on the extruded and expanded poly-ethylene panel in stead of the existing wet construction method. Compared to the existing method, this panel is light movably and is constructed simply. These representative construction merits are getting wide span in a bath due to reducing wall thickness and saving construction period.

• Nuclear Engineering and Technology
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• v.32 no.1
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• pp.67-76
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• 2000

Significant wall thinning due to flow accelerated corrosion(FAC）was recently reported in main feedwater pipes in 3 Korean pressurized water reactor(PWR) plants. The main feedwater pipes in one plant were repaired using overlay weld method at the outside of pipe, while those in 2 other plants were replaced with new pipes. In this study, the effect of the wall thinning in the main feedwater pipes on piping integrity was evaluated using finite element method. Especially, the effects of both the overlay weld repair and the stress concentration in notch-type thinned area on the piping integrity were investigated. The results are as follows : (1) The piping load carrying capacity may significantly decrease due to FAC. In special, the load carrying capacity of the main feedwater pipe was reduced by about 40% during about 140 months operation in Korean PWR plants. (2) By performing overlay weld repair at the outside of pipe, the piping load carrying capacity can increase and the stress concentration level in the thinned area can be reduced.

• Journal of the Korea Institute of Building Construction
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• v.5 no.3 s.17
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• pp.125-129
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• 2005

The waterproofing in slab and wall of underground structure, have a couple of construction methods which are inside waterproofing methods for inner surface, and outside waterproofing methods for out wall and slab surface waterproofing. In resent years, however, it has been adapted the inside waterproofing construction method, as increasing of construction expenses cost and low workability and technology, nevertheless, outside waterproofing has set a most high value construction method. In inside waterproofing construction method, it is difficult to repair and assure durability and safety for concrete which has direct water-press. So, It is necessary for adopt the outside waterproofing method. For that reasons, this study based on the application for outside waterproofing method on the under ground structure, to more increase durability, to introduce mono adhesive sheet waterproofing materials. as considering chemical, physical properties.

• Korean Architects
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• s.637
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• pp.126-131
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• 2022

• Korean Institute of Interior Design Journal
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• no.25
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• pp.103-110
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• 2000

The material world around human is normally composed of opaque one, with which human has made the spaces. The opaque material to make space has played a role to control the relationship among people and has produced socio-cultural things since the history started. The opening of opaque material(wall) connects one space with the other. Therefore, the meaning of opening is a connection among people who are in different spaces in terms of sociology. In conjunction with this, socio-cultural situation has been deployed differently. In the traditional european domestic space, the glass has been applied to this opening since they found the glass. It disconnects two spaces physically but connects them visually. Therefore, without blocking the opening visually, the glass became to protect people with their interior space from outside environment. The important thing is that the application of the glass in a building had been restricted because of opening size. However, after Industrial Revolution with the advanced technology of architecture, the glass came to be applied to the building and it became widen. So, the concept of glass window became to be the one of glass wall. This change made a transformation of visual character between two spaces which are separated with glass wall. This means that the glass wall gave two directional visibility while the glass window gave one directional visibility from inside to outside of space. This is because the amount of the natural light to the interior space increased due to widen glass in a space. This gave a change of visual authority and the space of surveillance(interior space) became to the one of communication. The space of surveillance, Michel Foucault mentioned in his book surveillance and punishment, is a very private one that is not visually permeable from the people outside, while the space of communication is a public one which needs other eyes. In the space of publicity, there needs a rationality, morality and ethics because of public surveillance and in the space of privacy, there restores a desire for sex and assaults.

• Journal of architectural history
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• v.29 no.3
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• pp.7-14
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• 2020

It can be meaningful that this study attempted to analyze the use cases and forms based on the literature on the painting walls of the J oseon Dynasty, and attempted basic research to prevent disaster damage using traditional elements. This study summarizes the use of the Hwabangbyeok wall of J oseon Dynasty as follows. First, Hwabangbyeok wall was used from the early J oseon Dynasty and was adopted by palaces and other major state facilities to cope with fire and theft. Second, the Hwabangbyeok Wall was also referred to as the wall below the lower part of the wall, and was constructed with the purpose of preventing disasters from outside. Third, in an analysis of the Daeseongjeon shrine of Hyanggyo, many construction cases were identified mainly in the Gyeonggi area, which is assumed to be based on production and construction conditions along with local climatic factors. Fourth, it can be said that the Hwabangbyeok wall was basically adopted to prevent comprehensive disaster risk reduction in case of external intrusion and fire.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.3
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• pp.65-71
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• 2003

In this research, we make the thin wall chamber to the measurement of heat flux of using a Kerosene/LOx liquid rocket engine's thrust chamber. The wall thickness is one millimeter. We measured outside wall temperature of thrust chamber by nine thermocouple. We suppose the system to the one-dimension unsteady state, and so the heat flux and heat transfer coefficient of thurst chamber are calculated using one-dimensional the transient energy equation by outside wall temperature. In this case, O/F ratio is 2.0, experimental variation is chamber pressure and we got the heat transfer coefficient of the proportion relation of 0.88 times for the chamber pressure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.5
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• pp.525-532
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• 2000

Evaporation heat transfer characteristics have been investigated experimentally when distilled water is sprayed on the outside wall of horizontal tubes in a evaporator. This problem is of particular interest in the design of evaporator of an absorption system. Hydrophilic surface treatment was employed to increase the wettability on copper tubes. The results indicate that evaporation heat transfer with hydrophilic tubes is shown to be 25-44% higher than that with bare tubes at evaporation pressure of 31.8 Torr(evaporation temperature$ 30^{\circ}C). Evaporation heat transfer rates of hydrophilic treatment tubes are improved substantially, comparing with those of conventional copper tubes in the wide range of operating parameters, such as water inlet temperatures, water mass flow rates and evaporation pressures.

• Journal of Environmental Science International
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• v.13 no.10
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• pp.929-938
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• 2004

Sludge discharger applied the principle of the air lift pump was investigated experimentally for the different design( diameter of discharge pipe, diameter and height of the inside and outside wall) and operating parameters(air flow rate, water level). And it was conducted that performance comparison about sludge discharger and conventional air lift pump. The result indicated that discharged liquid were increased with the increase of air flow rate and water level and decrease distance between inside and outside wall. The discharge pressure was increased with an increase of air flow rate and a decrease of the diameter of the discharge pipe, for both the sludge discharger and the airlift pump. The discharge pressures of the sludge discharger were 3-6 times higher than those of the air lift pump.