• Journal of the Korea institute for structural maintenance and inspection
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• v.17 no.5
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• pp.130-135
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• 2013

Anti-icing system can reduce traffic accidents and congestion by quickly removing the frozen road surface area. there is no decision criteria for determining application of the Anti-icing system in Korea. In this study, we proposed the decision criteria for determining application of the anti-icing system based on weather and road conditions, i.e., geometric and topographic conditions. Regional climate survey, Solar Radiation analysis, and dynamic vehicle simulation considered road geometry was conducted to standardize the installation method of anti-icing system. Also, we have developed a software that can be determined an installation of anti-icing system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.23 no.3
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• pp.293-301
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• 2005

In case of the roads that pass the mountain area, the cut sections or the tunnels are constructed. And In winter season it appears sunshine few in the specific segment, the shade is continued last and the freezing sections occur. So, the attention is necessary in traffic safety. This study was to evaluate the influence of sunshine and surface freezing sections expected in route plans of roads using GIS and makes alternative ideas in road stability security. After selecting 29 km sections of Donghae highway and creating a 3 dimensional terrain surface through the digital conversion of design plan data, it reflects the road alignment data of the same coordinates and a 3 dimensional road modeling is created. It set shadow time of road surface for the solar trace in the winter solstice in 20 minute interval. Shade areas are displayed and inputed in polygon data by manual vertorizing. Graphic and attribute data of this shade section is constructed in geodatabase of ArcCatalog. And it extracted the freezing section using intersect fuction of the GIS spatial analysis. By analyzing the winter meteorological data of temperature, rainfall, snowfall, humidity, and etc. and grasping dangerous freezing section of the road surface effectively, it will be able to make alternative ideas of the preliminary stability evaluation reflected in basic design.

• Journal of the Korean earth science society
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• v.32 no.7
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• pp.761-769
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• 2011

Daily minimum temperature and freezing data of the Seoul weather station ($37^{\circ}$34'N, $126^{\circ}$57'E, Songwol-dong Jongno-gu Seoul, hereinafter Songwol) and freezing data of the Han River station ($37^{\circ}$30'N, $126^{\circ}$57'E, hereinafter Han River) were used to study the long-term variation of the freezing climate for Seoul, Korea, for the period of 100 years from 1907 to 2006. 'Freezing' of Songwol is defined that the water in outdoor fields is frozen, and 'freezing' of the Han River located 6 km away from Songwol is defined as the region 100 meters upstream of the second and fourth piers in the south end of the Han River Bridge is fully frozen. The mean first freezing date for Songwol was October 28, and one for Han River was December 28; these showed a late tendency, with the rate of 0.78 days $decade^{-1}$ and 3.47 days $decade^{-1}$, respectively. The mean annual freezing days was 159.06 days for Songwol and 50.33 days for Han River; each showed a $decade^{-1}$shorter tendency, with rates of 2.01 days $decade^{-1}$ and 5.24 days $decade^{-1}$, respectively. All the seven no-freezing years (1960, 1971, 1972, 1978, 1988, 1991, and 2006) for Han River came after 1950. The mean daily minimum temperatures of the first freezing dates for Songwol and Han River were $0.55^{\circ}C$ and $-12.22^{\circ}C$. The first freezing occurred after 6.43 days for Songwol and after 8.94 days for Han River with daily minimum temperature below $0^{\circ}C$. The annual minimum temperatures of Songwol and Han River exhibited positive correlations with the first freezing date and negative correlations with freezing days. The result shows that the freezing climate change is relevant to temperature change and is a part of overall climate change. By conducting additional studies with various methods and wider region, we will be able to monitor the freezing climate.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.117-132
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• 2021

Due to the terrain in Korea, there are many road sections passing through mountainous areas. During the winter, there is a higher risk of traffic accidents, due to black ice caused by the lack of sunlight. Despite domestic road freezing safety measures, accidents caused by road freezing results in severe traffic accidents. Under these considerations, this study analyzed whether traffic safety signs that change in response to the external temperature help drivers recognize frozen road segments. The study was conducted through analysis of the effect of the signs on a driver's perspective. For the signs under development, out of the signs designed by experts, the sign design which received the highest visibility and effectiveness evaluation ratings from the general public was selected. The sign was implemented through Virtual Reality (VR) and installed on the right side of the road to analyze the effect on gazing and driving behavior. As a result of analyzing the driver's driving behavior, a speed reduction of about 7km/h or more was found in the sign section. Therefore, It was found that the existence of the sign had a strong relationship with the rate of the drivers' speed reduction.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2004.05a
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• pp.69-72
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• 2004

본 연구에서는 한라산 유역에서의 적설이 지하수 함양에 미치는 영향조사를 위해 물수지 분석을 통한 유출, 침투, 증발산량을 규명하였으며 그 결과는 다음과 같다. 1.‘03년 12월~’04년 2월 까지의 적설자료를 수집하여 선형모델인 Clark 모델 및 SCS 모델에 의해서 유출해석을 실시한 결과 융설에 의한 직접유출은 일어나지 않았다. 2. 증발산량을 Thornthwait 공식에 의해.산정한 결과 9.6cm가 발생하며, 침투량은 196.8cm가 발생하였다. 3. 본 연구기간내에 발생한 적설에 대한 물수지 분석 결과 한라산 적설이 지하수 함양에 미치는 영향은 30,186,365톤으로 나타났다. 4. 연구대상지역에서 현장 관측조사의 결과 표고 1,700m이상의 적설은 2월까지는 동결된 결빙상태로 남아 있고, 표고 1000m까지는 해빙과 결빙이 반복적으로 일어나고 있어 융설에 의한 부분적인 지하수 침투가 일어나며, 표고 1,000m에서부터 표고 600m까지의 지역인 경우 융설되어 지하침투가 활발히 일어나는 지역으로 나타났다.

• The Korean Journal of Quaternary Research
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• v.8 no.1
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• pp.43-68
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• 1994

전곡리 일대는 화산지형, 단층지형, 구석기 문화연구 등 여러 분야의 학문적 관심이 집중된 지역이다. 본 연구는 박편 분석, 물리화학 광물분석등이 수단을 활용하여 전곡리 용 암대지를 덮고 있는 피복물의 형성과 퇴적 후의 변화과정을 밝히려고 한 것이다, 여기서 다 음과 같은 사실을 밝힐수 있었다. 전곡리 용암대지는 Riss-Wrm 간빙기에는 별로개석되 지 않았다가 Wrm 빙가에 들어와 인근 황해의 해수면이 낮아지면서 개석된 것으로 추정 된다. 그리고 Wrm빙기 전기간에 걸쳐 용암대지에는 건육화된 황해와 인근 하천(한강, 임 진강) 범람원에서 바람에 의해 날려온 미립물질이 약 8m 이상 퇴적되었다. Wrm 빙기후 기에는 이풍적토(Loess)가 여름에도 녹지 않는 결빙층이 발달했을정도의 한랭 습윤했던 기 후의 영향을 받았다, 이로 인해 일련의 크랙(엽상구조를 이루는 수평크랙과 불규칙한 수직 방향크랙)들이 발달했고 풍적 물질의 미시적 조직과 구조도 많이 변화했다. 또한 결빙작용 으로 변형된 구조의 규제를 받으며 gleyzation 이 진전되었다. 단면 관찰에서 회백색 얼룩과 붉은 또는 검붉은 얼룩이 복잡하게 섞여 있는 모습은 바로 이것이 진전된 결과이다, 그간 발굴된 구석기 유물들은 결빙구조 및 gleyzation의 흔적이 잘 나타나는 부의에서 출토되었 다, 이사실은 본 지역의 구석기 인류가 생활했던 시기는 Wrm 빙기에서도 이러한 한랭 기후가 있기 이전이었음을 시사한다.

• Journal of Korean Society of societal Security
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• v.3 no.1
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• pp.43-50
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• 2010

Sliding accidents on the road have a high percentage by road freezing, especially, they often have appeared at bridges and Tunnel of freezing areas. Thus, the stability of road operations is enhanced by preventing partial freezing phenomenon. According to the geothermal snow melting system analysis, a pattern of thermal conductivity is found out; pavement materials of concrete and asphalt where the system is buried. The heat transfer simulation is essential when the geothermal snow melting system is applied according to heating exchanger pipe placed in the lower pavements. The model tests are conducted on low temperature in freezer using the manufactured test model which is equal to pavement materials. Many variables are discovered from numerical analyses under the same conditions with model test.

• Journal of Aerospace System Engineering
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• v.15 no.3
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• pp.45-56
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• 2021

Demand for UAM (Urban Air Mobility) aircraft is rapidly increasing in countries around the world due to the problem of traffic congestion in urban areas. Through research and development, various e-VTOL aircraft concepts are being prepared for commercialization, for which airworthiness certification is required, since it is a manned transportation mode for people to board. Factors that pose a fatal threat to the safe operation of UAM aircraft include lightning strikes that can cause damage to structures and disturb the navigation system, as well as icing that impairs flight stability. Since the current UAM aircraft-related lightning and icing certification technology development is insufficient, there is need to develop appropriate airworthiness certification guidelines. In this study, after analyzing the laws and regulations related to aircraft by the FAA and the EASA, we tried to incorporate the lightning and icing certification guidelines for the UAM aircraft. We also analyzed the effects of lightning and icing on UAM aircraft using computational simulation, and presented the basis for establishing practical guidelines for the certification of UAM aircraft to be adopted in the future.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.414-414
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• 2021

유역 상류의 지표수는 급경사로 인해 빠른 흐름을 나타냄으로써 유역의 저류기능은 하류부에 비해 부족한 형편이다. 또한 광역상수도의 공급이 불가능한 지역이 많아 소규모 급수시설을 이용하여 물공급에 대처하고 있다. 샌드댐은 이와 같은 물공급 소외지역의 저류기능을 높이기 위해 활용될 수 있으며 주된 특성은 증발에 의한 손실 방지와 겨울철 결빙에 따른 대처가 가능하다는 점이다. 본 연구에서는 춘천 물로리 지역을 중심으로 샌드댐의 공급기여도를 평가하기 위해 SWAT-MODLFOW모형을 이용한 수문성분 분석을 수행하였다. 그 결과 연구 지역의 수문성분 중 상당한 양의 측방 흐름이 발생하는 것을 알 수 있었다. 월평균 지하수 함양 분포는 유역의 제한된 지역에서만 발생했고, 토양 유형과 밀접한 관련이 있었다. 전체 지하수 함양량의 약 85 %는 지역의 여름과 봄철에 발생했고 연평균 함양률은 강수량의 약 6 %내외로 저조하였다. 하천과 대수층은 연결성을 나타냈으며 유역 출구 부근에서 하천유출량이 증가하는 양상을 나타냈다. 대수층과 샌드댐 저류지에서 이용 가능한 물의 양은 수위저하를 야기하지 않으면서 약 30m³/일의 물을 공급할 수 있음을 보여주었다. 현재 이 지역의 물 공급 수요는 15.4m³/일임을 감안하면 샌드댐 설치후 이 지역의 공급은 비교적 안정적일 것으로 기대된다.

• Journal of Korea Multimedia Society
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• v.14 no.3
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• pp.392-402
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• 2011

Snow fall and icing on traffic roads in the winter season cause not only inconvenience but unexpected traffic accidents, so the proper measures are needed. The existing road information system is being installed for steep slope roads in mountain areas, however, it is not widely adopted because it is too expensive. In this paper, a novel and cost-effective road weather information system especially for snow fall and icing on roads is proposed. The system consists of digital temperature and relative humidity sensor, infrared temperature sensor, ultrasonic sensor, CMOS camera, and two types of control/communication board for ubiquitous sensor network to send the data to server. The server program including the decision making method with received data is also described. Experimental results are provided to prove the feasibility of the proposed system.