• Journal of Korea Water Resources Association
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• v.56 no.7
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• pp.461-470
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• 2023

The purpose of this research is to derive the optimal temperature, location, and heating control system for a tipping bucket rain gauge heating system used for observing snowfall during winter. We conducted indoor and outdoor experiments by manufacturing a tipping bucket rain gauge that can be variably controlled for heating at the funnel, exterior, and interior, and indoor and outdoor. The indoor experiments involved using a temperature and humidity chamber to compare the performance and derive the appropriate temperature of the precipitation gauge heating system. Subsequently, the outdoor experiments were carried out at the Cloud Physics Observation Center located in Daeguallyeong, heavy snowfall region, to validate the findings. The analysis result was derived that the heating temperature of the funnel should be set at the 10 to 30℃, while the internal heating temperature should be 70℃. Furthermore, the optimal locations for the heating devices, which aim to minimize measurement delay, were identified as the exterior of the rain gauge, the rim of the funnel, and the vertical surface of the funnel. Our result shows that used as the basis for the operating conditions of precipitation gauge heating systems for solid precipitation measurement in winter.

• Journal of Environmental Science International
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• v.29 no.1
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• pp.1-13
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• 2020

Recently, a heavy rainfall with high spatial variation occurred frequently in the Korean Peninsula. The meteorological event that occurred in Busan on 3 May 2016 is characterized by heavy rain in a limited area. In order to clarify the reason of large spatial variation associated with mountain height and location of low level jet, several numerical experiments were carried out using the dynamic meteorological Weather Research and Forecasting (WRF) model. In this case study, the raised topography of Mount Geumjeong increased a barrier effect and air uplifting due to topographic forcing on the windward side. As a result, wind speed reduced and precipitation increased. In contrast, on the downwind side, the wind speed was slightly faster and since the total amount of water vapor is limited, the precipitation on the downwind side reduced. Numerical experiments on shifting the location of the lower jet demonstrated that if the lower jet is close to the mountain, its core becomes higher due to the effect of friction. Additionally, the water vapor convergence around the mountain increased and eventually the precipitation also increased in the area near the mountain. Hence, the location information of the lower jet is an important factor for accurately predicting precipitation.

• Atmosphere
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• v.27 no.3
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• pp.277-290
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• 2017

Characteristics of precipitation in South Korea during the 2016 Changma period (6/18~7/30) are analyzed in great details. El $Ni{\tilde{n}}o$-induced tropical Indian Ocean (IO) basin-wide warming lasts from spring to early summer and induces the western North Pacific subtropical high (WNPSH) circulation anomaly through an equatorial Kelvin wave during the 2016 Changma period. Along the northern edge of the WNPSH, strong precipitation occurred, in particular, over eastern China and southern Japan. During the Changma period, South Korea had the near-normal mean precipitation amount (~332 mm). However, about 226 mm of rain fell in South Korea during 1 July to 6 July, which amounts to 67% of total Changma precipitation in that year. Upper-level synoptic migratory lows and low-level moisture transport played an essential role, especially from 1 July to 3 July, in triggering an abrupt development of fronts over the Korean Peninsula and the eastern continent China. The front over the eastern China migrates progressively eastward, which results in heavy rainfall over the Korean peninsula from 1 to 3 July. In contrast, from 4 to 6 July, the typhoon (NEPARTAK) affected an abrupt northward advance of the North Pacific subtropical high (NPSH). The northward extension of the NPSH strengthens the Changma front and induces the southerly flows toward the Korean peninsula, giving rise to an increase in heavy rainfall. The NEPARTAK is generated due to interaction of the Madden-Julian Oscillation (MJO), equatorial Rossby wave and Kelvin waves.

• Korean Journal of Remote Sensing
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• v.30 no.4
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• pp.465-480
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• 2014

In this study, we analyzed the spatio-temporal variations of satellite imagery for the two heavy rainfall cases (21 September, 2010, 9 August, 2011) occurred in the Korean Peninsula. In general, the possibility of strong convection can be increased when the region with plenty of moisture at the lower layer overlapped with the boundary between dark and bright area in the water vapor imagery. And the merging of convective cells caused by the difference in the moving velocities of two cells resulted in the intensification of convective activity and rainfall intensity. The rainfall intensity is more closely linked with the minimum cloud top temperature than the mean cloud top temperature. Also the spatio-temporal variations of rainfall intensity are impacted by the existence of merging processes. The merging can be predicted by the animation of satellite imagery but earlier detection of convective cells is almost impossible by using the infrared and water vapor imagery.

• Journal of the Society of Disaster Information
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• v.8 no.2
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• pp.119-137
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• 2012

In this study, the damages and condition of road pavement were analyzed using pavement management system (PMS) for the structural improvement. Problems of road pavement management were issued by in-depth interview with workers in charge of plant, construction and supervision. By surveying advanced road pavement management, the way how to improve road pavement management in Seoul was discussed. In conclusion, it is necessary to take measures against road heavy traffic and heavy rain in summer. It was found that the problem of early damages of road pavement due to uniform layout with analyzing life cycle cost (LCC). According to the results of survey, it was suggested to strength practical training and to control precisely the temperature of pavement in the process of production and construction.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.70-82
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• 2020

Recently, a lot of damages have been caused by urban flooding, and heavy rainfall that temporarily occur are the main causes of these phenomenons. The damages caused by urban flooding are identified as the change in the water balance in urban areas. To indirectly identify it, this research analyzed the change in the remote sensing indices on each land cover before and after heavy rainfall by utilizing daily precipitation data and multi-temporal Sentinel-2 satellite imagery. Cases of heavy rain advisory and warning were selected based on the daily precipitation data. And statistical fluctuation were compared by acquiring Sentinel-2 satellite images during the corresponding period and producing them as NDVI, NDWI and NDMI images about each land cover with a radius of 1,000 m based on the Seoul Weather Station. As a result of analyzing the maximum value, minimum value, mean and fluctuation of the pixels that were calculated in each remote sensing index image, there was no significant changes in the remote sensing indices in urban areas before and after heavy rainfall.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.173-180
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• 2019

This study was conducted to understand factors affecting TSS and heavy metals transport on the road, parking lot and roof. During storm events, heavy metals, which were mostly attached to TSS, were also transported when TSS was washed off in the road, parking lot and roof. This finding may be supported by the significant correlations between TSS load and total and soluble heavy metals load including Cr, Fe, Cu, and Pb (Pearson r value: 0.52 to 0.73; probability p value<0.01). Generation and transport of TSS and heavy metals were greater in the road and parking lot compared to the roof due to vehicular activities, slope and greater catchment areas of these sites. It was found that TSS transport during peak flows of storm events ranges from 65% to 75% implying that by controlling peak flows, TSS transportation to nearby water bodies may be decreased. Depending on the target TSS and heavy metal reduction, sizing of low impact development (LID) technologies and green infrastructures (GI) such as infiltration trench, tree box filter, and rain garden may be calculated. Future researchers were recommended to assess the limitations of the systems and determine the design considerations for these types of facilities.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.3
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• pp.343-345
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• 1993

Eight hundred and seventy on goats from Naikhongchari FSR site in Bandarban district were examined for gastro-intestinal nematodes. The parasites encountered in the region were Haemonchus Sp, Bunostomum Sp, Oesophagostomum Sp and Strongyloides Sp. The overall infection rate was 78.41%. Among various species found. Haemonchus Sp emerged as the most prevalent, although Oesophagostomum and Bunostomum were also found in this studies. The seasonal fluctuation in infection was assessed by monitoring the fecal egg count. The maximum values for the prevalence and overall mean EPG were observed after the heavy rain fall season and remained at a relatively high level from June to November. Haemonchus Sp and Oesophagostomum Sp appeared to be of major important parasites in the goats of this climatic zone which deserved proper treatment to attain higher production from goat.

• Smart Structures and Systems
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• v.11 no.5
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• pp.453-476
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• 2013

DuraMote is a remote sensing system developed for the "NIST TIP project: next generation SCADA for prevention and mitigation of water system infrastructure disaster". It is designed for supervisory control and data acquisition (SCADA) of ruptures in water pipes. Micro-electro mechanical (MEMS) accelerometers, which record the vibration of the pipe wall, are used detect the ruptures. However, the performance of Duramote cannot be verified directly on a water distribution system because it lacks an acceptable recordable level of ambient vibration. Instead, a long-span cable-stayed bridge is an ideal test-bed to validate the accuracy, the reliability, and the robustness of DuraMote because the bridge has an acceptable level of ambient vibration. The acceleration data recorded on the bridge were used to identify the modal properties of the structure and to verify the performance of DuraMote. During the test period, the bridge was subjected to heavy rain, wind, and a typhoon but the system demonstrates its robustness and durability.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.327-331
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• 2007

Inundation of substation and underground power equipment(pad-mounted transformers & switches) breaks out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. In case inundation of substation and underground power equipment, it occurs a great economic loss owing to recovery time and events of electric shock occur by inundation electrical facility. So we search the damage situation and installation situations. Therefore we propose the necessity of protection of flood at low-lying downtown and low-tying shore. This paper will be used to present a reform proposal of electrical related law about flood protection of existing power equipment.