• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.36-41
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• 2016

In this study, numerical analyses were used to investigate the performance of a coupling control method for the dynamic responses of adjacent buildings under multiple hazards. Numerical simulations were done using the earthquake loads of regions with strong seismicity in Los Angeles, California, and the wind loads in regions with strong winds in Charleston, North Carolina. The artificial earthquake and wind loads were made using SIMQKE and Kaimal Spectrum based on ASCE 7-10. Ten-story and twenty-story adjacent buildings were selected as example structures, and nonlinear hysteretic dampers were used to connect them. The Bouc-Wen model was used to model the nonlinear hysteretic dampers. The results show that the proposed control method could effectively reduce the dynamic responses, and the optimal control designs were different for each hazard.

• Atmosphere
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• v.31 no.4
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• pp.361-376
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• 2021

"Gangwon Yeongdong Wind Experiments (G-WEX) Pilot Study: Downslope windstorms in the Taebaek Mountains, South Korea" is promoted based on joint organization by Gangwon Regional Office of Meteorology and National Institute of Meteorological Research and participation by 12 institutions to understand the mechanism in development of Yeongdong wind phenomena. The special observation (G-WEX) involved total of 5 intensive observations in March 2020 and April 2020. To collect the data necessary for the research on Yeongdong wind phenomena, (1) high-resolution surface observation network was used to examine surface wind and (2) atmospheric soundings were observed by using Rawinsonde, Wind profiler, Wind Lidar, and Drone. This study covers the detailed information on the special observational experiments for downslope windstorms in the leeward of the Taebaek Mountains, named as the Yeongdong wind, including the observational strategies, experimental designs, and pilot studies during the Intensified Observing Period (IOPs). According to 2020 G-WEX observation results, downslope windstorms were observed in 2~3 km of upper atmosphere when the strong winds happened around the top of the mountain near Daegwallyeong. Also, dry adiabatic expansion related to downslope windstorms caused temperature rise and led to formation of an inversion layer in altitude below 2.5 km. Bands of strong wind were located right under the altitude where downslope windstorms are observed with temporal rise of the temperature. As these are preliminary observation results, there needs to be continuous related researches and high-resolution weather observation.

• KIPS Transactions on Computer and Communication Systems
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• v.11 no.11
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• pp.411-418
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• 2022

Incorrectly loaded containers can easily knock down by strong winds. Container collapse accidents can lead to material damage and paralysis of the port system. In this paper, We propose a deep learning-based container loading state and accident risk detection technique. Using Darknet-based YOLO, the container load status identifies in real-time through corner casting on the top and bottom of the container, and the risk of accidents notifies the manager. We present criteria for classifying container alignment states and select efficient learning algorithms based on inference speed, classification accuracy, detection accuracy, and FPS in real embedded devices in the same environment. The study found that YOLOv4 had a weaker inference speed and performance of FPS than YOLOv3, but showed strong performance in classification accuracy and detection accuracy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.101-103
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• 2022

CCTV is mainly used as a real-time detection system for critical facilities. In the case of CCTV, although the accuracy is high, the viewing angle is narrow, so it is used in combination with a sensor such as a radar. LiDAR is a technology that acquires distance information by detecting the time it takes to reflect off an object using a high-power pulsed laser. In the case of lidar, there is a problem in that the utilization is not high in terms of cost and technology due to the limitation of the number of simultaneous processing sensors in the server due to the data throughput. The detection method by the optical mesh sensor is also vulnerable to strong winds and extreme cold, and there is a problem of maintenance due to damage to animals. In this paper, by using the 1550nm wavelength band instead of the 905nm wavelength band used in the existing lidar sensor, the effect on the weather environment is strong and we propose to develop a system that can integrate and control multiple sensors.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.4
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• pp.125-132
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• 2022

It can be seen that Traditional house of Jeong Si-yeong is located in a place where Saenggi(good energy), which is important in Pungsu(Feng Shui), can be gathered and that energy can be properly maintained. According to the theory of feng shui, a place that is not easily exposed by the surrounding mountains and is well protected by the strong wind was selected, and the main room was placed on the south side so that the sunlight was adequate while facing the north, so that you can live a comfortable life for a long time. Located on such a relatively well-hidden site, it is a location that can cope well with the invasion of Japanese invaders through the sea in the past, and even today, it is seen as a reasonable base that can be properly protected from strong sea winds in reality. On the other hand, if we look at the Hyungguk theory, it was a house built in the late Joseon Dynasty, and we could see the hidden hopes of the nobles at the time. The mountain behind the house is a haebok-type with a crab lying on the seashore, and what the crab symbolizes is the past national exam for official. Considering that the name of the place where the house is located is also Oyat(cucumber tree)-ri, where many cucumber trees closely related to the royal family of the Joseon Dynasty were planted, it seems that the family wished for prosperity by producing many Sadaebu(upper class gentry) in the past and forming a good relationship with the royal family.

• 한국해양학회지
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• v.18 no.2
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• pp.149-160
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• 1983

Extensive wind, sea level and sea surface temperature (SST) data collected along the east coast of Korea in 1973-1979 were used to ascribe the variations of sea level and SST associated with wind forcing during summer. Alongshore components of wind were dominant but the offshore components were little significance in the southeast coast in summer. The variations in SST and sea level adjusted barometricallyagreed with the upwelling-downwelling processes and showed a rapid response to wind.Appearance of cold water to the surface in the upwelling region concurred well with te periods of positive y-component wind when the tangential line at Ulgi was takem as the y-axis. In general, SST at Ulgi and Gampo as well as the adjusted sea level at Pohang, Ulsan and Busan decreased significantly when strong winds favorable for upwelling persisted for more then three days whereas they increased during the relaxation or unfavorable periods. The period of an upwelling event, on the average, was about 10 days and the mean speed of alongshore sind was 4.0m/sec.

• Journal of the Korean Solar Energy Society
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• v.32 no.spc3
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• pp.185-193
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• 2012

Recently rapid urbanization facilitates development of high-rise building complex including apartment and office building in urban area. Many problems related with high -rise building are reported. Especially, unpleasant strong winds in pedestrian area are frequently encountered around the high-rise building. CFD simulation methods are used to analyze the wind environment of pedestrian level in high-rise building block. However, the results show differences between CFD and measurement. This difference is attributed to improper use of CFD. Conventional CFD simulation for wind environment around high-rise building does not describe the effect of trees, shrubs and plants near ground which affect the wind environment of pedestrian level. Canopy model can be used to reproduce the aerodynamic effects of trees, shrubs and plants near ground. In this paper, CFD simulation methods coupled with the tree canopy model to predict wind environment of pedestrian level in high-rise residential building block were suggested and the validity was analyzed by comparison between measurement and CFD results.

• Smart Structures and Systems
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• v.11 no.5
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• pp.435-451
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• 2013

High-rise buildings are a common feature of urban cities around the world. These flexible structures frequently exhibit large vibration due to strong winds and earthquakes. Structural control has been employed as an effective means to mitigate excessive responses; however, structural control mechanisms that can be used in tall buildings are limited primarily to mass and liquid dampers. An attractive alternative can be found in outrigger damping systems, where the bending deformation of the building is transformed into shear deformation across dampers placed between the outrigger and the perimeter columns. The outrigger system provides additional damping that can reduce structural responses, such as the floor displacements and accelerations. This paper investigates the potential of using smart dampers, specifically magnetorheological (MR) fluid dampers, in the outrigger system. First, a high-rise building is modeled to portray the St. Francis Shangri-La Place in Philippines. The optimal performance of the outrigger damping system for mitigation of seismic responses in terms of damper size and location also is subsequently evaluated. The efficacy of the semi-active damped outrigger system is finally verified through numerical simulation.

• Ocean and Polar Research
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• v.34 no.4
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• pp.395-401
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• 2012

Ten-year AVHRR sea surface temperature data obtained in the Yellow Sea are put into EOF analyses. Temperature variation is predominated by the first mode which is associated with the seasonal fluctuation of temperature with annual range decreasing with the bottom depth. Since such a strong annual signal may mask the upwind or downwind flows occurring intermittently during the winter, only the data obtained during this season are put into EOF analyses. Every winter shows similar results. The first mode, explaining more than 90% of total variance, appears to be a part of the seasonal variation of temperature mentioned above. In the second mode, the time coefficient is well correlated with northerly winds to which the responses of the trough and shallow coastal areas are opposite to each other. A simple theoretical consideration suggests the following physical explanation: The northerly wind stress anomaly creates an upwind (downwind) flow over the trough (coastal) areas, which then induces a temperature increase (decrease) by advection of heat, and vice versa for the southerly wind stress anomaly. Hence, this paper provides further evidence of the intermittent upwind or downwind flows occurring in the Yellow Sea every winter.

• Journal of Environmental Science International
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• v.15 no.6
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• pp.527-532
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• 2006

The purpose of this study is to clarify the characteristic of urban heat island intensity in urban area formed at a basin. Thermal environments for basin-type cities are influenced by significant topographic relief winds. In this study, we analyzed the diurnal variations of the heat island intensity according to meteorological condition and season using AWS(Automatic Weather observation System) data in Daegu Metropolitan area for 1 year(3/April, 2003 $\sim$ 2/April, 2004). In this study, we defined the urban heat island intensity as the air temperature difference between two points, the downtown and the suburban area. The suburban area is located at valley mouth around the western tip of Daegu. The results are summarized as follows; 1. The maximum heat island intensity was recorded at early morning under the meteorological conditions, calm and clear 2. The heat island intensity was strong in the order of winter, fall, spring and summer. 3. The heat island intensity came out minus values in the afternoon. This phenomenon is known as a com mon for basin-type cities. 4. The heat island intensity was twice or more in clear and calm than not so.