• 대기
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• 제19권4호
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• pp.331-344
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• 2009

A sensitivity study has been performed using ARPS (Advanced Regional Prediction System) version 5.2.10 in a downslope windstorm case of 12-13 February 2006. The purpose of this study was to find out the role of the inversion layer of temperature mainly in relation to the strength of the downslope winds over the Yeongdong region located downstream of the Taebaek mountains. Under the conditions of N (Brunt-$V{\ddot{a}}is{\ddot{a}}la$ frequency)=0.008 and N=0.016, the effects of the presence of the inversion layer, its variation of height of the layer, and the depth of the layer were identified. The sensitivity experiments suggested that the inversion layer effected the downstream wind speed of the mountains under both conditions of N=0.008 and N=0.016, and notably when the inversion layer was located near the mountain crest the downstream wind speed of the mountains was strong (~ $27ms^{-1}$) only under the condition of N=0.016. In addition, when the atmosphere was rather stable (N=0.016) and the depth of the layer was relatively thin (765 m) the downstream wind speed of the mountains was the strongest (~ $30ms^{-1}$) among the sensitivity experiments.

• 대기
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• 제19권1호
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• pp.9-36
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• 2009

Two heavy snowfall events occurred in Yeongnam and Yeongdong regions of the Korean Peninsula during the period from 4 to 6 March 2005 are analyzed. The events were developed by two different meso-scale snow clouds associated with an extratropical low passing over the Western Pacific. Based on synoptic data, GOES-9 satellite images, and precipitation amount data, the events were named as Sokcho and Busan cases, respectively. We analyzed the development mechanism of the events using meterological variables from the NCEP(National Centers for Environmental Prediction) /NCAR(National Centers for Atmospheric Research) reanalysis data such as potential vorticity(PV), divergence, tropopause undulation, static stability, and meridional wind circulation. The present analyses show that in the case of Sokcho, the cyclonic circulation in the lower atmosphere in the strong baroclinic region induced the cyclonic circulation in the upper atmosphere. The cyclonic circulation in the lower and upper atmosphere caused a heavy snowfall in the Sokcho region. In the case of Busan, the strong cyclonic circulation in the upper atmosphere was initiated by the stratospheric air intrusion with the high positive PV into the troposphere during the tropopause folding. The upper strong cyclonic circulation enhanced the cyclonic circulation in the lower disturbed atmosphere due to the extratropical low. This lower cyclonic circulation in turn, intensified the upper cyclonic circulation, that caused a heavy snowfall in the Busan region.

• 대기
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• 제25권2호
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• pp.261-270
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• 2015

Characteristics of snowfall and snow crystal habits have been investigated in the campaign of Experiment on Snow Storms At Yeongdong (ESSAY) using radiosonde soundings, Global Navigation Satellite System (GNSS), and a digital camera with a magnifier for taking a photograph of snowfall crystals. The analysis period is 6 to 14 February 2014, when the accumulated snowfall amount is 192.8 cm with the longest snowfall duration of 9 days. The synoptic situations are similar to those of the previous studies such as the Low pressure system passing by the far South of the Korean peninsula along with the Siberian High extending to northern Japan, which eventually results in the northeasterly or easterly flows and the long-lasting snowfall episodes in the Yeongdong region. In general, the ice clouds tended to exist below around 2~3 km with the consistent easterly flows, and the winds shifted to northerly~northwesterly above the clouds layer. The snow crystal habits observed in the ESSAY campaign were mainly dendrite, consisting of 70% of the entire habits. The rimed habits were frequently captured when two-layered clouds were observed, probably through the process of freezing of super-cooled droplets on the ice particles. The homogeneous habit such as dendrite was shown in case of shallow clouds with its thickness of below 500 m whereas various habits were captured such as dendrites, rimed dendrites, aggregates of dendrites, plates, rimed plates, etc in the thick cloud with its thickness greater than 1.5 km. The dendrites appeared to be dominant in the condition of cloud top temperature specifically ranging $-12{\sim}-16^{\circ}C$. However, the association of snow crystal habits with temperature and super-saturation in the cloud could not be examined in the current study. Better understandings of characteristics of snow crystal habits would contribute to preventing breakdown accidents such as a greenhouse destruction and collapse of a temporary building due to heavy snowfall, and traffic accidents due to snow-slippery road condition, providing a higher-level weather information of snow quality for skiers participating in the winter sports, and estimating more accurate snowfall amount, location, and duration with the fallspeed of solid precipitation.

• 대기
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• 제30권2호
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• pp.183-193
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• 2020

In this study, Yeongdong cold air damming (YCAD) cases that occur in winters have been selected using automatic weather station data of the Yeongdong region of Korea. The vertical and horizontal scales of YCAD were analyzed using rawinsonde and numerical weather model. YCAD occurred in two typical synoptic patterns such that low pressure and trough systems crossing and passing over Korea (low crossing type: LC and low passing type: LP). When the Siberian high does not expand enough to the Korean peninsula, low pressure and trough systems are likely to move over Korea. Eventually this could lead to surface temperature (3.1℃) higher during YCAD than the average in the winter season (1.6℃). The surface temperature during YCAD, however, was decrease by 1.3℃. The cold air layer was elevated around 120 m~450 m for LP-type. For LC-type, the cold layer were found at less than approximately 400 m and over 1,000 m, which could be thought of combined phenomena with synoptic and local weather forcing. The cross-sectional analysis results indicate the accumulation of cold air on the east mountain slope. Additionally, the north or northeasterly winds turned to the northwesterly wind near the coast in all cases. The horizontal wind turning point of LC-type was farther from the top of the mountain (52.2 km~71.5 km) than that of LP-type (20.0 km~43.0 km).

• 고문화
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• 69호
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• pp.63-89
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• 2007

본고는 지금까지 조사된 강원지역의 점토대토기 출토 유적의 양상을 바탕으로 그 상한연대 및 전개과정과 성격을 고찰하였다. 이를 위해 그동안 발굴조사된 유적을 중심으로 입지와 분포, 유구의 규모와 구조, 그리고 출토 유물의 양상을 분석하였다. 강원지역 점토대토기 출토 유적의 양상을 살펴보면 영서지역과 영동지역 간에는 입지 및 유구의 규모와 구조는 차이가 없으나, 점토대토기의 형태 등 출토 유물의 양상에 다소 차이가 있다. 필자는 유구와 유물의 양상에 대한 분석을 바탕으로 강원지역의 점토대토기문화는 영서에서 영동지역으로의 단선적인 전파가 아니라 여러 전파경로를 통해 유입되었을 가능성을 제시하였다. 그리고 유적의 탄소 연대 측정결과를 검토해 보았을 때, 점토대토기문화의 상한연대를 기원전 4세기 후반에서 2세기 전반으로 보고 있는 기존의 연구 결과보다 시기가 앞서고 있으며, 지석묘의 하부구조에서 확인되는 사례도 있어 강원지역의 점토대토기문화는 이전의 지석묘를 축조하던 무문토기문화와 일정 기간동안 병존하였던 것으로 보인다.

• 한국치위생학회지
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• 제11권1호
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• pp.69-79
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• 2011

Objectives : The purpose of this study was to examine the curriculum, educational facilities and employment guidance of the departments dental hygiene in junior colleges in different regions and the satisfaction level of students with their major in an effort to provide some information on the improvement of educational environments and satisfaction level with the major. Methods : The subjects in this study were 315 dental hygiene students in several junior colleges located in Seoul, Gangwon Province and South Jeolla Province. A survey was conducted during a 15-day period from April 15 to March 1, 2010. Results : As for educational environments and satisfaction level with the major, they gave 3.18, 2.95 and 3.11 respectively to satisfaction level with curriculum, facilities/employment guidance and the major. In terms of satisfaction with educational environments by academic year, the juniors and seniors expressed much satisfaction with the qualifications of professors, the preparation of labs and practice devices, the utilization of labs and practice devices and a supply of employment information. By region, the students from the metropolitan area were satisfied a lot with curriculum, the qualifications of professors, practice-centered curriculum, the preparation of labs and practice devices, the utilization of labs and practice devices, the system of employment guidance and a supply of employment information. By credit, the students tho got A expressed lots of satisfaction with the quality of instruction. Concerning satisfaction level with their major by academic year, the juniors and seniors were highly satisfied with relationship with dental hygiene professors and social status of dental hygienists. By school location, the students from the metropolitan area expressed a lot of satisfaction with the content of major courses and social status of dental hygienists. Conclusions : In order to boost the satisfaction level of students in non-metropolitan areas, colleges should try to improve educational environments, and full-fledged assistance should be provided to them.

• 대기
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• 제28권2호
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• pp.187-200
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• 2018

The heavy snowfall phenomenon with thunder and lightning occurred in Yeongdong coastal region on 20 January 2017. Amount of snow on that day was a maximum of 47 cm and was concentrated in a short time (2 hours) at the Yeongdong coastal area. The mechanism of thundersnow was investigated to describe in detail using observational data and numerical simulation (Weather Research and Forecast, WRF) applied lightning option. The results show that a convective cloud occurred at the Yeongdong coastal area. The east wind flow was generated and the pressure gradient force was maximized by the rapidly developed cyclone. The cold and dry air in the upper atmosphere has descended (so called tropopause folding) atmospheric lower layer at precipitation peak time (1200 LST). In addition, latent heat in the lower atmosphere layer and warm sea surface temperature caused thermal instability. The convective cloud caused by the strong thermal instability was developed up to 6 km at that time. And the backdoor cold front was determined by the change characteristics of meteorological elements and shear line in the east sea. Instability indexes such as Total totals Index (TT) and Lightning Potential Index (LPI) are also confirmed as one of good predictability indicates for the explosive precipitation of convective rainfall.

• 한국지역지리학회지
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• 제13권4호
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• pp.381-395
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• 2007

한국 사회의 민주화와 소선거구제로의 변화로 또한 지역기반 정당의 출현으로 13대 총선 이후 전국적인 투표 행태가 종래 여촌야도에서 지역주의적인 양상으로 바뀌었다. 충북 전북 경북의 접경지역인 영동군, 무주군, 김천시를 대상으로 지역적 정당정체성의 변화를 검토하고, 각 후보자 선택 기준의 중요도를 비교하여 투표 행태를 규명해 보고자 하였다. 시군 단위로 볼 때, 타도와의 문화적 친화성으로 인해 영동군은 전면적으로 무주군은 부분적으로 지역당에 대한 지지가 약화되는 반면, 김천시는 지역당에 대한 지지가 확고한 것으로 나타났다. 읍면 단위로 본 이웃효과는 3 시군 모두에서 부분적으로만 확인되었다. 후보자의 정치적, 사회적 특성이 유권자의 투표행위라 할 수 있는 득표율에 어느 정도 영향을 미치는지를 선형근사식을 통해 살펴 본 결과, 여러 설문조사와는 다르게 후보자의 소속 정당이나 출신지역 등 지역적인 선택 기준을 중시하고 있다. 지난 17대 총선을 기점으로 지역정당이 쇠퇴하고 있어 향후 정치적 지역주의에 어떠한 변화가 초래될지 주목된다.

• 대기
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• 제30권2호
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• pp.169-181
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• 2020

We conducted a study on the impact of observation station density; this was done in order to enable the accurate estimation of spatial meteorological variables. The purpose of this study is to help operate an efficient observation network by examining distributions of temperature, relative humidity, and wind speed in a test area of a three-dimensional meteorological observation project in the Yeongdong region in 2019. For our analysis, we grouped the observation stations as follows: 41 stations (for Step 4), 34 stations (for Step 3), 17 stations (for Step 2), and 10 stations (for Step 1). Grid values were interpolated using the kriging method. We compared the spatial accuracy of the estimated meteorological grid by using station density. The effect of increased observation network density varied and was dependent on meteorological variables and weather conditions. The temperature is sufficient for the current weather observation network (featuring an average distance about 9.30 km between stations), and the relative humidity is sufficient when the average distance between stations is about 5.04 km. However, it is recommended that all observation networks, with an average distance of approximately 4.59 km between stations, be utilized for monitoring wind speed. In addition, this also enables the operation of an effective observation network through the classification of outliers.

• 대기
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• 제33권1호
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• pp.21-32
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• 2023

Characteristics of downslope windstorm (DW) has been examined mainly based on 1-min average wind and the other meteorological conditions in the Yeongdong region for 2000~2020. First, a classification procedure for the downslope windstorm is proposed using surface wind speed (greater than 99 percentile), 1-hour longevity of strong wind (SW), westerly wind direction, low humidity (less than 20 percentile), and leeside warming. The number of DW days satisfying the proposed criteria is 221 (2.9% of total days and 47.5% of SW days) while the number of SW days is 465 (6.1% of total days) for 2000~2020. The occurrences of both SW and DW shows distinctive annual variation with its peak in April. In addition, mean wind speed of DW days is 8.2 m s^-1 with its duration of 2 hr 30 min and relative humidity of 28% at Gangneung. An episode (7 May 2021) was selected by applying the proposed criteria to SW days of 2021. The sounding shows that the layer of wind speed greater than 25 m s^-1 was lowered down to 925 hPa at Gangneung (leeside) relative to 850 hPa at Hoengseong (Wonju), in the afternoon along with significant warming and drying. Froude numbers of Wonju and Gangneung for the DW events were increased 4 and 5 times greater than those of normal days, respectively. This kind of DW long-term statistics in the leeside of the mountains is thought to build a foundation of further understanding DW mechanism.