• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.7
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• pp.621-627
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• 2013

Field tests of hybrid desiccant cooling systems were conducted from July to August 2011. Data were monitored and transferred in real time over the Internet. The monitored variableswere analyzed to determine the performance characteristics under outdoor conditions. A series of system simulations has been conducted for outdoor conditions of the field tests. The results agree well with the experimental data in general. The system performance has been shown to deteriorate for wetter conditions, as predicted by the simulation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.211-218
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• 2006

From the development of residential flat plate system, continuously bended shear reinforcement is developed for the prevention of punching shear. To know the punching shear capacity of developed shear reinforcement in slab-column joint, structural test is performed. The testing parameters are shear reinforcement types, such as no reinforcement, bended shear reinforcement, and head stud reinforcement. To verify the lateral capacity, cyclic load is applied under the constant vertical load condition. The results of tests are compared to as global displacement, slab-column joint strength. From the test results, the resisting capacity of developed shear reinforcement system has a good performance in the story drift ratio.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.199-200
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• 2014

최근 국내에서는 경제적 여유와 함께 웰빙에 관심이 높아지며 도심생활에서 벗어나 수변공간, 해양레저활동 등이 주목받고 있다. 이에 따라 수상에서의 다양한 활동을 수용할 수 있는 플로팅 건축물에 대한 관심이 증가하고 있으며, 플로팅 건축물을 이용한 다양한 용도와 기능의 건축물들이 수상에 설치되고 있다. 플로팅 건축물 역시 사람들의 생활을 위한 공간으로 육상의 일반 건축물과 같이 쾌적한 거주환경 제공을 위하여 다양한 설비들이 설치되고 있다. 하지만 플로팅 건축물은 수상에 위치한 입지적 특성으로 인하여 육상의 일반건축물과 다른 환경적 요인을 고려한 설비시스템 도입이 필요함에도 불구하고 수상환경을 고려한 설비시스템의 설치는 이루어지지 않고 있다. 특히, 실내의 쾌적한 거주환경 유지를 위하여 중요한 요소인 냉난방설비는 충분한 성능을 발휘하기 위하여 시스템설계 전 충분한 환경적 요소를 고려한 부하산정이 필요하다. 따라서 본 연구에서는 플로팅 건축물의 입지적 특성을 고려하여 냉난방 시스템 설계 시 일반건축물에 적용되는 부하산정 요소 외 해수온도, 해수면 반사일사 및 창면적비를 부하산정 요소로 도입하고 각 요소별 특성을 고찰하여 플로팅 건축물 냉난방부하에 어떤 영향을 미치는지에 대하여 종합적으로 고찰하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.307-317
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• 2011

This paper is to investigate the possibility of the elastic seismic design for highrise buildings through seismic performance evaluation for potential earthquakes that wind-designed highrise buildings located in strong wind zone and low seismicity can be experienced. Highrise steel diagrid frames which is the most loved structural system in recent years were wind-designed and the substantial system overstrength due to wind design procedure is verified, For the highrise steel diagrid frames, the response spectrum analysis and the seismic performance evaluation by various soil sites were conducted. It was showed that highrise steel diagrid frames with slenderness of greater than 5.2 under strong wind and low seismic zones such as Korea peninsula can resist elastically for the 500 year return period earthquake and have the possibility of seismic design for the 2400 year return period earthquake. In the member level, highrise steel diagrid frames with slenderness of greater than 5.2 all presented the immediate occupancy level regardless of soil sites for the 500 year return earthquake and excluding the $S_E$ soil site for the even 2400 year return period earthquake. In the system level, highrise steel diagrid frames with slenderness of greater than 5.2 showed the immediate occupancy level for $S_A$ and $S_B$ soil sites and the life safety for $S_C$ to $S_E$ soil site in the 500 year return period. The seismic performance level of highrise steel diagrid frames for the 2400 year return period earthquake displayed one step lower than the 500 year return period earthquake.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.211-216
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• 2005

The authors carried out experiment, Computer Fluid Dynamics(CFD) and energy simulation of simulator. As a results of experiment and CFD, diffuser velocity is very important design factor for occupied zone air conditioning in Under Floor Air Distribution(UFAD) system. Then, in contrast to energy consumption of the Overhead system, the UFAD system could reduce 6.4% of the total energy because of occupied tone air conditioning. It concluded that tile UFAD system is more effective in energy Performance than the Overhead system.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2015.11a
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• pp.16-17
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• 2015

본 논문에서는 실내 환경 중 TV 시청환경에서 마이크로폰 어레이를 이용하여 다양한 다중 음원 방향을 추정하는 기법을 제안한다. 제안된 기법은 기존의 하나의 음원에 특화되어 있는 GCC-PHAT 기반의 방법을 GCC-PHAT 버퍼와 NMF를 도입하여 다중음원의 방향 추정을 가능하게 만들었다. 제안된 기법의 성능을 평가하기 위해서 실 거주 환경에서 발생하는 소음원과 TV 소리 방향 추정 결과에 대한 실측치와 추정치 간의 오차인 절대 평균오차를 측정하였으며, 실험 결과 제안한 기법이 기존의 방법인 GCC-PHAT보다 우수한 추정 성능을 보임을 확인하였다.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.5
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• pp.85-91
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• 2003

TLCD is a good alternative to TMD for control of structures because of its cost efficiency, ease of installation, little maintenance requirement, potential for multiple usage, and ease of re-tuning. In this study, the control performances of TMD and TLCD are evaluated and compared for seismically excited structures. Results show that TLCD is more effective than TMD for interstory drift control while TLCD is as effective as TMD for acceleration control. In special. it is shown that interstory drifts are maximally controlled in lower floors and accelerations are reduced most in upper floors. This indicates that TLCD is an effective controller for earthquake-induced structures in terms of structural safety as well as serviceability.

• Journal of the Korean Wood Science and Technology
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• v.40 no.1
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• pp.10-18
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• 2012

A high airtightness is required for the residential spaces constructed recently to save cooling and heating energy through improving insulation performance. Because the chances to release steam formed by human activity in building and inflow of water vapor in outdoor air to residential space are reduced, the natural humidity control performance of interior materials has become more important. In this study, hygroscopic performance of thermo-physically treated wood (Pinus koraiensis) was estimated. At various relative humidity condition, the water vapor adsorption and desorption rates of wooden materials were measured as well as equilibrium moisture content. Effects of roughness and surface microstructure as physical factors and functional groups as chemical factors on the hygroscopicity were analyzed. It is expected that the results from this study and further study of measuring moisture generation in residential spaces could contribute to install a system for evaluating the hygrothermal performance of wooden building.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.522-532
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• 2015

In the present study, a tunnel type soundproof wall with partial opening is proposed to reduce the environmental noise caused by railway vehicles traveling on bridges, which affects residents of high-rise apartment buildings; the study also attempts to minimize load due to wind and the weight of the wall. Applying the principles of computational fluid dynamics and structural mechanics, and the ray tracing method, a reduction in noise as well as of the overall weight of the soundproof walls is estimated. Analysis results show that the proposed soundproof wall with a partial opening weighs less, while reducing the wind loading by up to 30%. To prevent direct propagation of sound through openings in the wall, an acoustic louver, which is a type of silencer, could be considered for the opening. In order to achieve a similar noise effect with existing insulation material, the fluid flow and the insulation effect of the acoustic louver are analyzed. As the considered opening is in the range of 30~40% of the total length of the soundproof wall, the noise effect and wind load are reduced by 10dB and 25% respectively. Consequently, opening some part of tunnel type soundproof walls and installing louvers on the wall openings can have the effects of weight-reduction and reduced wind load. If a partial opening is applied with proper sound material application, a gain of an additional 5~10dB of noise reduction can be achieved.

• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.1
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• pp.55-63
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• 2013

In this study, seismic performance was evaluated considering the deterioration level for the low-rise and moderate buildings with non-seismic details which are most common in Korea. Evaluation results showed that the deterioration condition is relatively good even after 24 years of construction but the seismic performance did not satisfy the protection index in the first and second evaluation. In case of the third evaluation, the goal performance was satisfied based on the interstory drift ratio but reinforcement is found to be necessary. Seismic performance was evaluated after the target buildings were reinforced in the walls, bracing, and damper. Results showed the interstory drift ratio drastically reduced regardless of reinforcement methods and satisfied the level of immediate occupancy. In case of wall reinforcement, however, base shear increased more than double which requires review on the existing foundation.