• KIEAE Journal
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• v.2 no.3
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• pp.17-24
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• 2002

For sustainable building design, using day lighting is considered a variable technique to save energy and create comfort indoor environments. Specially, the lightself as a integrated daylighting system is one of the most important techniques due to it's durability, availability and lighting performance. This paper aims to analyze the development and architectural application of a lightself system to buildings as a integrated day lighting system. For the study, advanced lightself systems developed in abroad such as "Integrated Enveloped and Lighting System", "Anidolic Daylighting System" and etc. are analyzed. Also, the architectural examples are investigated. As results, the new technologies such as optically treated reflective and sun-tracking are adopted to improve daylight performance. And, lots of environmentally friendly buildings are installed on integrated lightself system.

• Journal of the Korean Institute of Educational Facilities
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• v.18 no.3
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• pp.35-41
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• 2011

Performance of a small-capacity solar absorption cooling system was investigated experimentally. Ten sets of evacuative-tube solar-heat collectors and a 5 kW single-stage absorption cooler were combined to produce a hybrid cooling system. The performance of the cooling system was measured using a tim-coil unit installed in a small plastic storage. It was found from the test on a sunny day of May that when the temperature of the hot water supplied from the solar collectors to the generator of the absorption cooler reached $60^{\circ}C$, the absorption cooler started cooling and the cold water temperature measured from the fan-coil unit reached $18^{\circ}C$. The COP, which is defined as the ratio of the cooling power to the total electrical power input was higher than 1.0.

• Journal of the Korean Institute of Educational Facilities
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• v.6 no.4
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• pp.16-23
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• 1999

The thermal and condensation performance of steel stud walls are monitored in steel-framed schools of Ee-Wol Elementary School and kindergarten using temperature and humidity sensors installed. The monitoring process carried out during the summer and winter period, shows decrement effect of the external heat flow to be quite remarkable and excellent. And steel stud walls provides a highly efficient time-lag effect in spite of its light weight property, with 30 minutes to 4 hours time-lag for external heat flow, which variation mainly depends on its location of each part of the wall. Any condensation phenomena are not observed in either external or internal surfaces.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.2
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• pp.209-214
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• 2009

The simulation software for predicting the performance of a wind turbine generator system (WTGS) is validated using the field measured data obtained from the idling test run of a dual rotor wind turbine recently developed and installed in Korea. Both steady-state and transient responses at low and high wind conditions are compared with the theoretically predicted ones from the simulation software WINSIM.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1245-1246
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• 2007

In present, as the various PV system have been installed and disseminated, research and development of photovoltaic(PV) system is the most important issues to establish usefulness of design, installation, supervision and maintenance of PV system with performance improvement. This paper presents evaluation and analysis method for estimating performance and losses of PV system and components using monitoring data.

• Journal of Power System Engineering
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• v.15 no.5
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• pp.5-9
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• 2011

The hydraulic piston using a hydrostatic bearing has been used widely due to its satisfying performance at very high pressurized circumstance and relative higher power density in comparison to conventional one. For high pressurization, enhanced efficiency and long durability of the hydraulic piston, the design of hydrostatic bearing is at issue, which is installed between piston shoe and swash plate. The performance of the hydrostatic bearing is influenced significantly by the assembly of the piston shoe consisting of circular land and recess. In this study, to estimate the performance of the hydrostatic bearing, the characteristics for lubrication of the assembly of the piston shoe were investigated by measuring a leakage rate of hydraulic fluid under an experimental condition, where a rotating velocity of the piston, hydraulic pressure and temperature of the hydraulic fluid were changed systematically. In addition, a film thickness of the hydraulic fluid on the piston shoe was measured and compared to theoretical one.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.719-724
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• 2006

The purpose of this study is on the performance evaluation of horizontally installed HGHEX(Horizontal-type Geothermal Heat Exchanger) in the summer season and the winter season. Followings are the results. By the result of data acquisition at the site, $2.5{\sim}2.7^{\circ}C$ temperature differences are gained between supply pipes and return pipes of HGHEX in the summer season. And $0.5{\sim}1.5^{\circ}C$ temperature differences are gained from HGHEX in the winter season. With these temperature differences, heat quantity of rejection and absorption is calculated and the performance of HGHEX is evaluated according to the seasons.

• The Journal of Korea Robotics Society
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• v.14 no.1
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• pp.14-21
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• 2019

In the ground environment, mobile robot research uses sensors such as GPS and optical cameras to localize surrounding landmarks and to estimate the position of the robot. However, an underwater environment restricts the use of sensors such as optical cameras and GPS. Also, unlike the ground environment, it is difficult to make a continuous observation of landmarks for location estimation. So, in underwater research, artificial markers are installed to generate a strong and lasting landmark. When artificial markers are acquired with an underwater sonar sensor, different types of noise are caused in the underwater sonar image. This noise is one of the factors that reduces object detection performance. This paper aims to improve object detection performance through distortion and rotation augmentation of training data. Object detection is detected using a Faster R-CNN.

• Geomechanics and Engineering
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• v.24 no.4
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• pp.337-348
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• 2021

Brillouin Optical Frequency Domain Analysis (BOFDA) is a distributed fiber optic sensing (DFOS) technique that has unique advantages for performance monitoring of piles. However, the complicated production process and harsh operating environment of offshore PHC pipe piles make it difficult to apply this method to pile load testing. In this study, sensing cables were successfully pre-installed into an offshore PHC pipe pile directly for the first time and the BOFDA technique was used for in-situ monitoring of the pile under axial load. High-resolution strain and internal force distributions along the pile were obtained by the BOFDA sensing system. A finite element analysis incorporating the Degradation and Hardening Hyperbolic Model (DHHM) was carried out to evaluate and predict the performance of the pile, which provides an improved insight into the offshore pile-soil interaction mechanism.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.59-60
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• 2021

To measure the effect of the stress-strain dispersion across the installed waterproofing layer on the concrete surface, a strain gauge was attached to the gap between the waterproofing layer and the concrete structure at specified points of upper, center and bottom of the load-displacement simulation specimen, and the peak stress-strain at the displacement interface were measured and compared with stress-strain at other areas to analyze each material types' stress-strain dispersion ratio properties. Based on the results of the testing, it was shown that materials with high load-displacement resistance performance accordingly had high stress-strain dispersion ratio results, and the materials from highest performance to lowest performance were; CAS, SAS, PUC and CSC.