• KIEAE Journal
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• v.3 no.2
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• pp.37-44
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• 2003

The aim of this study was to analyze the thermal performance through Test-Cell of TI-wall in domestic climate. This study was carried out as follows: 1) The TI-wall was studied for ability to reduce heat loss through the building envelope and analyzed to TIM properties. 2) Test models of TI-wall were designed through the investigation of previous paper and work, measured for winter and spring, and the thermal effects were analyzed. The type of the TIM used in test model is small-celled(diameter 4mm and thickness 50mm) capillary and cement brick(density $1500kg/m^3$) was used by thermal mass. 3) Test-cell of TI-wall was calibrated from measured data and the dynamic simulation program ESP-r 9.0. In these simulations, the measured climate conditions of TaeJon were used as outdoor conditions, and the simulation model of Test-cell was developed. 4) The sensitivity analysis is executed in various aspects with standard weather files and ESP-r 9.0, and then most suitable system of TI-wall are predicted. Finally, The suitable system of TI-wall was analysed according to sizes of air gap, kinds, thickness, and the surface absorption of therm wall. The result is following. In TI-wall, Concrete is better than cement brick, at that time the surface absorption is 95%, and the most efficient thickness is 250mm. As smaller of a air gap, as reducer of convection heat loss, it is efficient for heating energy. However, ensuring of a air gap at least more than 50mm is desirable for natural ventilation in Summer.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.19-20
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• 2015

Building exterior wall's energy loss is very high rate comparing to all part of a buildings. And it account for upper 40% of cooling and heating load. So many studies conducted improving insulation performance of building's exterior, appeared about sandwich insulation wall which could be gaining merit of traditional insulation method those are exterior insulation and interior insulation. In this study, we inform structural performance of sandwich insulation wall for RC wall. For this, first, we define each wall's role and design sandwich insulation wall. At last, analyze structural performance of sandwich insulation wall. This study can contribute to apply it safely where side wall which toilet, stair area, etc.

• Journal of the Korean Geotechnical Society
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• v.27 no.2
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• pp.53-62
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• 2011

During the construction of vertical cutoff walls, filtration of bentonite slurry into the adjacent soil formation fabricates a layer of bentonite filter cake on the wall surface. The bentonite filter cake possesses much lower hydraulic conductivity compared to that of backfill materials in the cutoff wall. Hydraulic conductivity of bentonite filter cakes formed with three different types of bentonites has been measured by performing the modified fluid loss test under various pressure levels. Three different mixture ratios, 4, 6, and 8%, were selected for fabricating bentonite filter cakes to represent common field conditions. Two analysis methods for interpreting the experimental data from the modified fluid loss tests were employed to estimate hydraulic conductivity of the bentonite cakes. The range of hydraulic conductivities of the three bentonite cakes is between $2.15{\times}10^{-11}\;m/s$ and $2.88{\times}10^{-10}\;m/s$ which is 1 to 2.7 orders of magnitude lower than that of the design cutoff wall backfill. The stress distribution and thickness of the bentonite cakes were also evaluated in this paper.

• Journal of Ocean Engineering and Technology
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• v.20 no.4 s.71
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• pp.17-23
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• 2006

Monotonic four-point bending tests were conducted on straight pipe specimens, 102 mm in diameter with local wall thinning, in order to investigate the effects of the depth, shape, and location of wall thinning on the deformation and failure behavior of pipes. The local wall thinning simulated natural erosion/corrosion metal loss. The deformation and fracture behavior of the straight pipes with local wall thinning was compared with that of non wall-thinning pipes. The failure modes were classifiedas local buckling, ovalization, or crack initiation, depending on the depth, shape, and location of the local wall thinning. Three-dimensional elasto-plastic analyses were carried out using the finite element method. The deformation and failure behavior, simulated by finite element analyses, coincided with the experimental results.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.1
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• pp.56-63
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• 2012

In this study, a field applicability of reboiler tube was evaluated by comparing ECT signal with IRIS signal about wall loss rate and remaining wall thickness using worked austenite STS 316L ASME standard calibration tube. In the case of wall-loss rate, as a result, tolerance about $20%{\times}4$ flat bottom hole and 10% O D groove(ECT), 80% defect and 10% O D groove(IRIS) occurred up to ${\pm}15%$. In the case of remaining wall thickness, ECT was satisfied with the both tolerance, but tolerance about 80% defect occurred up to ${\pm}15%$ in IRIS. Therefore, if the IRIS is performed for interpretation of non-relevant indication and measurement of wall-loss rate after ECT, reliability is supposed to be improved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.942-945
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• 2006

In order to measure the sound transmission loss(STL) of a test specimen such as windows, which is smaller than the test opening, a special partition is built into the test opening and the specimen is placed in that partition. This paper discusses how the measured STL is changed by the partition when a small-size window of high sound insulation is mounted. Theoretical and experimental investigations are carried out to quantify the effect of the filler wall. The results reveal that the smaller the window size is, the higher sound insulation performance of the filler wall is required in order to measure the accurate STL of the specimen. It is found that the insufficient sound insulation of the filler wall leads to the lower measured value of the window's STL.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1315-1317
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• 2008

The plasma display panel is an image expression display using gas discharge. However gas discharge characteristics vary with temperature. Furthermore, the potential difference among three electrodes appears in sustain period due to external applied voltages. It affects to the wall charge state accumulated on the electrodes. This research aims at identifying that the discharge characteristics depend on the potential difference and temperature. The results show that the wall charge loss increases with increase of the number of applied pulse during sustain period and it severely appears at high temperature.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.221-225
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• 2007

Recently, on account of stress relief and settlement of a healthy drinking culture, many people are visiting a song practice room. In case of such song practice room, since the mechanical voice through a loud accompaniment-music and microphone is on using, there has made a very loud noise, and it influences a lot to the adjacent other space and song practice room booth. Consequently, from the designing stage an efficient measures for soundproof and sound-insulation should be arranged. However, as most of the song practice room wall-bodies that already built up or under construction step were constructed merely with consideration on an interior-wise factor only, it is suffering at the soundproof and sound-insulation. Reflecting such viewpoint, this Study has measured Sound Transmission Loss on the subject for the song practice room wall-body recently built up, and based on the actually measured data, by practice of comparison?analysis on it using various evaluation methods, would intends to present a fundamental material for establishment an efficient sound-insulation measure.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.59-60
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• 2019

Thermal bridge on a building envelope causes additional heat loss which increases the heating energy consumption. As the higher building insulation performance is required, heat loss through thermal bridge becomes higher proportion among total building heating energy consumption. For the exterior insulation and finish system, thermal bridge between window frame and concrete wall should be constidered as one of main reasons of heat loss. In this study, the thermal bridge barrier between window frame and concrete wall(STAR) was proposed as the best practice for reducing thermal bridge. The STAR was confirmed that the use of thermal bridge barrier imporved the annual heat energy capacity by 35% or more and the innitial construction cost by 7.4% or less because of additional interior insulation against condensation. Finally the life cycle cost during 20 year by heating energy of a building reduced by 25% or more compared with the exist technology. This STAR thermal bridge barrier will be used as the main technology to improve the energy efficiency of building.

• Journal of the Korean Solar Energy Society
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• v.28 no.1
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• pp.75-81
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• 2008

Thermal performance of passive solar Trombe wall system which is applied on the south wall of KIER Zero energy Solar House has been monitored for 6 months of heating season. Based upon the long-term measurement results, extensive statistical analysis was conducted to investigate temperature profiler and heat flow pattern in Trombe wall system under actual operating condition. Heat flow characteristics depending on the time variation of day and month was clearly revealed. Heat gain and loss on the inner surface of the Trombe wall was calculated base upon measured temperature data. Those results would be utilized to improve the efficiency of new type solar storage wall system.