• Journal of the Korean earth science society
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• v.28 no.5
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• pp.613-619
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• 2007

Mesoscale low is often observed over the downstream region of the East Sea (or, northwest coast off the Japan Islands) during East-Asia winter monsoon. The low system causes a heavy snowfall at the region. A series of numerical experiments were conducted with the aid of a regional model (MM5 ver. 3.5) to examine the formation mechanism of the mesoscale low. The following results were obtained: 1) A well-developed mesoscale low was simulated by the regional model under real topography, NCEP reanalysis, and OISST; 2) The mesoscale low was simulated under a zonally averaged SST without topography. This implies that the meridional gradient of SST is the main factor in the formation of a mesoscale low; 3) A thermal contrast ($>10^{\circ}C$) of land-sea and topography-induced disturbance served as the second important factor for the formation; 4) Paektu Mountain caused the surface wind to decelerate downstream, which created a more favorable environment for thermodynamic modification than that was found in a flat topography; and 5) The types of cumulus parameterizations did not affect the development of the mesoscale low.

• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.259-270
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• 2009

The objective of this study is to provide systematic design of the Korea's Integrated Road Transport System in intelligent transport systems. Integrated Road Transport System services support safety driving and traffic information for travellers, and rapid response of the system for emergency status not only dissemination of traffic for traffic but also flood, heavy snowfall, falling rocks, closed-road, collapse, accident and so on. Therefore, integrated road transport system service contributes national highway safety management system to the voice of the nation of integrated road transport system center service for user friendly.

• Journal of the Korea Society of Computer and Information
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• v.14 no.6
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• pp.153-164
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• 2009

The objective of this study is to provide systematic design of the Korea's highway advisory radio system in intelligent transport systems. Highway advisory radio services support safety driving and traffic information for travellers, and rapid response of the system for emergency status not only dissemination of traffic for traffic but also flood, heavy snowfall, falling rocks, closed-road, collapse, accident and so on. Therefore, highway advisory radio service contributes national highway safety management system to the voice of the nation of user-centered traffic information service.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.3
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• pp.7-14
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• 2023

Recently, the importance of impact-based forecasting has increased along with the socio-economic impact of severe weather have emerged. As news articles contain unconstructed information closely related to the people's life, this study developed and evaluated a binary classification algorithm about snowfall damage information by using media articles text mining. We collected news articles during 2009 to 2021 which containing 'heavy snow' in its body context and labelled whether each article correspond to specific damage fields such as car accident. To develop a classifier, we proposed a probability-based classifier based on the ratio of the two conditional probabilities, which is defined as I/O Ratio in this study. During the construction process, we also adopted the n-gram approach to consider contextual meaning of each keyword. The accuracy of the classifier was 75%, supporting the possibility of application of news big data to the impact-based forecasting. We expect the performance of the classifier will be improve in the further research as the various training data is accumulated. The result of this study can be readily expanded by applying the same methodology to other disasters in the future. Furthermore, the result of this study can reduce social and economic damage of high impact weather by supporting the establishment of an integrated meteorological decision support system.

• The Korean Journal of Quaternary Research
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• v.14 no.2
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• pp.117-123
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• 2000

This study examined the spatial distribution of precipitation in Sokcho area. The hourly, daily and monthly precipitation on the 2 stations, 5 AWS in Sokcho area were analyzed by daily, monthly, altitudinal distribution and synoptic environment. The results of the Study are as follows. The amount of Yearly precipitation, 1970~1999 in Sokcho area is gradually increasing. The amount of monthly precipitation 1970~1999 at Sorak weather observation station (altitude 148m), Compared with that in 7 Stations is greatest in spring, Summer and autumn. Because the valleys near Ssangcheon river are funnels for sea wind into Sorak weather observation station. The amount of Summerly precipitation at Mishiryong(1993~1999), the highest altitude in 7 weather observations stations is more 95.2mm than that of Sokcho airport, the lowest altitude, but the amount of winterly precipitation at Sokcho airport is more 89.6mm than that of Mishiryong. When the heavy rainfall and the heavy Snowfall occured in Sokcho area, wind systems were mainly a sea wind (north-north-eastly wind, north-westly wind) and daily mean wind speed was respectively 4.4㎧, 3.6㎧. The amount of the heavy rainfall and heavy snow fall in Sokcho area is closely associated with the north-eastly stream at the lower and the upper level toward the coast of East sea(Sokcho area).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2447-2453
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• 2013

In this study, the effects of weather conditions such as rainfall, discomfort index, snowfall, and sensible temperature on public transport demand in Seoul were analyzed using statistical data. The reasons were also derived from the survey. The data for the analysis were collected over the weekdays and weekends, and seasonal data of summer and winter were also gathered separately. Rainfall amount, discomfort index, and sensible temperature except snowfall amount, whose samples were insufficient, decreased the public transport demand by 2-7%. Rainfall amount and sensible temperature were statistically significant. Correlation analysis also showed that rainfall amount and sensible temperature are highly correlated with the demand. To find the reasons, the survey was conducted on citizens living in the Seoul Metropolitan Area. About 30% of the respondents wished to give up using bus when rainfall was heavy or temperature was low. On the contrary, auto and subway users increased by 10%. The results of this study could be used as the basic data when the public transportation planning or operation related policies according to the weather condition are concerned.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.3
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• pp.127-134
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• 2018

Electric transmission towers are facilities to transport electrical power from a plant to an electrical substation. The towers are connected using power lines that are installed with a proper sag by loosening the cable to lower the tension and to secure the sufficient clearance from the ground or nearby objects. The power line sag may extend over the tolerance due to the weather such as strong winds, temperature changes, and a heavy snowfall. Therefore the periodical mapping of the power lines is required but the poor accessibility to the power lines limit the work because most power lines are placed at the mountain area. In addition, the manual mapping of the power lines is also time-consuming either using the terrestrial surveying or the aerial surveying. Therefore we utilized multiple overlapping images acquired from a low-cost drone to automatically reconstruct the power lines in the object space. Two overlapping images are selected for epipolar image resampling, followed by the line extraction for the resampled images and the redundant images. The extracted lines from the epipolar images are matched together and reconstructed for the power lines primitive that are noisy because of the multiple line matches. They are filtered using the extracted line information from the redundant images for final power lines points. The experiment result showed that the proposed method successfully generated parabolic curves of power lines by interpolating the power lines points though the line extraction and reconstruction were not complete in some part due to the lack of the image contrast.

• Atmosphere
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• v.22 no.1
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• pp.57-71
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• 2012

Influences of orographic and ocean effect, which depend on the detailed geographic characteristics, upon winter time (December-February) precipitation in the Yeongdong region are investigated. Most of precipitation events in the Yeongdong region during the wintertime are associated with moist northeasterly (coming from the northeast direction) winds and also the spatial distribution of precipitation shows a great difference between Mountain area (Daegwallyeong) and Coastal area (Gangneung). The linear correlation coefficient between the meteorological variables obtained from NCEP/NCAR Reanalysis Data and precipitation amount for each precipitation type is calculated. Mountain type precipitation is dominated by northeasterly wind speed of the low level (1000 hPa and 925 hPa) and characterized with more precipitation in mountain area than coastal area. However, Coastal type precipitation is affected by temperature difference between ocean and atmosphere, and characterized with more precipitation in coastal area than mountain area. The results are summarized as follows; In the case of mountain type precipitation, the correlation coefficient between wind speed at 1000 hPa (925 hPa) and precipitation amount at Daegwallyeong is 0.60 (0.61). The correlation is statistical significant at 1% level. In the case of coastal type precipitation, the correlation coefficient of temperature difference between ocean and 925 hPa (850 hPa) over the East sea area and precipitation amount at Gangneung is 0.33 (0.34). As for the mountain type precipitation, a detailed analysis was conducted in order to verify the relationship between precipitation amount at Daegwallyeong and low level wind speed data from wind profiler in Gangneung and Buoy in the East Sea. The results also show the similar behavior. This result indicates that mountain type precipitation in the Yeongdong region is closely related with easterly wind speed. Thus, the statistical analysis of the few selected meteorological variables can be a good indicator to estimate the precipitation totals in the Yeongdong region in winter time.

• Journal of Navigation and Port Research
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• v.31 no.6
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• pp.555-562
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• 2007

The environs of Korea in winter season are influenced by the distribution of atmospheric pressure, namely, the typical east-low and west-high pattern that is formed from both the Siberian continental high pressure and the Aleutian oceanic low pressure. In this reason, the violent West or North-West monsoon, the billows with the strong wind, and the tremendous heavy snowfall are encountered very frequently in the West Sea. In this study, the trajectories of the extratropical cyclone are analysed to choose the safe refuge areas of National Fishery Supervision Vessel using the surface analysis weather chart for 11 years from 1994 to 2004. The safe refuge areas according to the trajectories of the extratropical cyclone in the West Sea are decided using data that contain the topographical properties of island, the depth of water, the state of low quality, the influence of tidal current, and the distribution of fishing-net.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.2
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• pp.109-117
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• 2012

Recently, large-scale multi-hazards have been occurred in the various areas of the world. A variety of Earth observation sensors such as satellite EO, aerial and terrestrial LiDAR have been utilized for global natural disaster monitoring. Especially, commercial satellites which observe the Earth regularly and repeatedly, and acquire images with cm-level high spatial resolution enable its applications to extend in the fields of disaster management from advanced disaster monitoring to timely recovery. However, due to existing satellite operation systems with some limitations in almost real-time and wide regional disaster response, close international collaborations between satellite operating organizations like NASA, JAXA, KARI etc. have been required for collecting satellite images in time through a satellite platform with multi-sensors or satellite constellation. For responding domestic natural disaster such as heavy snowfall and extreme rainfall in 2011, this paper proposes a disaster management system for timely decision-making; rapid acquisition of satellite imagery, data processing, GIS analysis, and digital mapping through cooperation with NDMI in Korea and International Charter-Space and Major disasters.