• 대기
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• 제19권2호
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• pp.155-168
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• 2009

Characteristics of seasonal mean diurnal temperature range (DTR) and their causes over South Korea are investigated using the 60 stations data of Korea Meteorological Administration from 1976 to 2005. In general, the seasonal mean DTR is greatest during spring (in inland area) and least during summer (urban and coastal area). The spatial and seasonal variations of DTR are closely linked with the land surface conditions (especially vegetation activity and soil moisture) and atmospheric conditions (cloud amount, precipitation, local circulation). The seasonal mean DTR shows a decreasing trend at the major urban areas and at the north-eastern part of South Korea. Whereas, it shows an increasing trend at the central area of the southern part. Decreasing and increasing trends of DTR are more significant during summer and fall, and during spring and winter. The decrease (increase) of DTR is mainly caused by the stronger increase of daily minimum (maximum) temperature than daily maximum (minimum) temperature. The negative effects of precipitation and cloud amount on the DTR are greater during spring and at the inland area than during winter and at the coastal area. And the effect of daytime precipitation on the DTR is greater than that of nighttime precipitation.

• 농촌의학ㆍ지역보건
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• 제26권1호
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• pp.115-119
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• 2001

사회적 통계 작성할 때 계절변동효과는 자료에 많은 영향을 미친다. 농촌의 의료기관에 내원한 환자들의 수도 계절에 영향을 많이 받는다. 1994년에서 2000년까지 농촌 보건지소에 내원한 환자 수를 분석하여 계절지수를 구하였다. 의료고유의 요인을 제거하기 위하여 감기 환자를 제외하고 계절지수를 구하였다. 각각의 계절지수는 다음과 같다. 1. 전체지수는 1월에서 12월 0.96, 1.08, 1.23, 0.83. 0.82, 0.75, 1.01, 0.99, 1.02, 1.05, 1.13, 1.13이다. 2. 감기환자를 제외한 지수는 0.94, 0.90. 1.42, 0.94, 0.91, 0.77, 1.13, 0.92, 0.84, 1.07, 1.10, 1.06이다. 위의 결과를 보면 봄, 초여름에 환자 수가 감소하고 한여름과 겨울에 환자가 증가한다. 이것은 감기 환자를 제외하고 분석하여도 같은 결과이다. 또한 이것은 농사의 주기와도 일치한다. 계절변동 지수를 잘 활용한다면 농촌을 대상으로 한 보건 연구나 사업계획에 많은 도움이 될 것이다.

• Ocean and Polar Research
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• 제29권2호
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• pp.113-121
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• 2007

The sound wave in the sea propagates under the effect of water depth, sound speed structure, sea surface roughness, bottom roughness, and acoustic properties of bottom sediment. In shallow water, the bottom sediments are distributed very variously with place and the sound speed structure varying with time and space. In order to investigate the seasonal propagation characteristics of low-frequency sound wave in the Yellow Sea, propagation experiments were conducted along a track in the middle part of the Yellow Sea in spring, summer, and autumn. In this paper we consider seasonal variations of the sound speed profile and propagation loss based on the measurement results. Also we quantitatively investigate variation of bottom loss by dividing the propagation loss into three components: spreading loss, absorption loss, and bottom loss. As a result, the propagation losses measured in summer were larger than the losses in spring and autumn, and the propagation losses measured in autumn were smaller than the losses in spring. The spreading loss and the absorption loss did not show seasonal variations, but the bottom loss showed seasonal variations. So it was thought that the seasonal variation of the propagation loss was due to the seasonal change of the bottom loss and the seasonal variation of the bottom loss was due to the change of the sound speed profile by season.

• Fisheries and Aquatic Sciences
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• 제4권3호
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• pp.101-111
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• 2001

In an attempt to demonstrate the seasonal variation of the Ulleung Warm Eddy (UWE), in which the UWE changes its shape from a warm core ring in early spring to a warm lens in late summer under the effect of surrounding East Korean Warm Current (EKWC) Water, a simple geostrophic adjustment model is considered. Model results indicate that the buoyancy increase of the EKWC Water and the strengthening of the EKWC towards summer, both of which are typical of this region, are the major factors governing the seasonal variation of the UWE.

• 자원ㆍ환경경제연구
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• 제31권3호
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• pp.343-365
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• 2022

본 논문은 정부가 시행한 1차 계절관리제의 초미세먼지 농도 감소 효과를 통계적 기법을 통해 확인하는 것이다. 특히 본 논문은 이러한 정책효과가 지역별(서해안, 남해안, 동해안)로 차이가 발생할 수 있다는 가설을 검정하는 것이다. 이를 위해 본 논문은 이중차분법(DID, difference-in-difference)을 활용하여 정책 시행 기간(2019년 12월~2020년 3월) 지역과 무관하게 발생한 코로나19, 따듯한 겨울 등 시간적 특이성을 제거하여 순수한 정책효과만 분석하였다. 분석 결과 석탄화력발전소에 대한 정부의 1차 계절관리제는 초미세먼지 감소 효과가 있었으나, 지역별로 그 효과에 차이가 존재하였다. 특히 서해안 지역의 감소 효과가 가장 크고, 남해안 지역이 그다음으로 효과가 있었으나 동해안 지역의 경우 감소 효과가 통계적으로 확인되지 못했다. 결과적으로 본 논문은 현재와 같이 지역과 무관하게 계절관리제를 운영하는 방식은 개선될 필요가 있다는 시사점을 도출하였다.

• 대기
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• 제20권4호
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• pp.437-449
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• 2010

The relocation effect of observation station (REOS) on the homogeneity of seasonal mean of maximum and minimum temperature, diurnal temperature range (DTR) and relative humidity (RH) was investigated using surface observation data and document file. Twelve stations were selected among the 60 stations which have been operated more than 30 years and relocated over one time. The data from Chunpungryeong station were used as a reference to separate the impacts of station relocation from the effects caused by increased green house gases, urbanization, and others. The REOS was calculated as a difference between REOS of relocated station and REOS of reference station. Although the REOS is clearly dependent on season, meteorological elements, and observing stations, statistically significant impacts are found in many stations, especially the environment of observing station after relocation is greatly changed. As a result, homogeneity of seasonal mean of meteorological elements, especially DTR and RH, is greatly reduced. The results showed that the effect of REOS, along with the effect of urbanization, should be eliminated for the proper estimation of climate change from the analysis of long-term observation data.

• 대한교통학회지
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• 제18권5호
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• pp.7-16
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• 2000

본 논문은 고속도로사고의 시간-공간적 반복성을 검증하고 이러한 현상의 원인을 규명하는 연구이다. 이를 위해 중부고속도로를 대상으로 계절성 유무검증과 계절성인자의 요인분석을 위한 계절군집별 모형을 개발, 해석하였다. 먼저 자가조직지도와 사고지표(월평균 사고율과 월평균 대물피해환산치) 분석을 통해, 국내 고속도로사고의 계절성이 존재하는 것을 확인하였으며, 집합적 계층적 군집분석기법을 사용하여 적정 계절군집수를 분석한 결과 겨울군집 봄가을군집, 여름군집의 3개 군집으로 분리되었다. 또한 해당 군집의 대표값은 겨울군집이 사상 자수와 사고차량수는 적은 반면 사고의 치명도는 매우 높은 것으로 나타났으며, 여름군집은 사상자수와 사고차량수는 많은 반면, 사고의 치명도는 다소 낮은 것으로 나타났다. 또한 계절군집별로 회귀모형식을 개발하여 계절군집별 사고특성을 검토한 결과, 계절성 유발인자(교통량, 안개, 결빙일수, 강설량, 강우량)와 계절군집의 사고가 매우 밀접한 관계를 가지고 있었으며 이들의 차이에 따라 국외 또는 지역별로 계절성의 특성이 다소 달라지는 것으로 분석되었다. 아울러, 이러한 연구결과는 사고다발지점선정기법, 사고예측 및 기술 모형 개발, 안전 관리를 위한 재원의 배분문제 등의 사고안전관리계획을 합리화하는 기초자료로 활용되리라 판단된다.

• 한국환경과학회지
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• 제20권9호
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• pp.1141-1149
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• 2011

The three-dimensional hydrodynamic model was simulated to understand coastal sea front of formation and seasonal variation in the Southern Sea of Korea. In this study, we used to concept of stratification factor, to realize seasonal distribution of stratification coefficient which of seasonal residual flow, considered with, tide, wind and density effect. Tidal current tends to flow westward during the flood and eastward during ebb. The current by the wind stress showed to be much stronger the coastal than the offshore area in the surface layer. And the current by the horizontal gradient of water density showed to be relatively weak in the coastal area, with little seasonal differences. On the other hand, the flow in the offshore area showed results similar to that of the Tsushima Warm Current. The stratification factor (SHv) was calculated by taking into account the total flow of tide, wind and density effect. In summer, the calculated SHv distribution ranged from 2.0 to 2.5, similar to that of the coastal sea front. The horizontal temperature gradient showed to be strong during the winter, when the vertical stratification is weak. On the other hand, the horizontal gradient became weak in summer, during which vertical stratification is strong. Therefore, it is presume that the strength of vertical stratification and the horizontal temperature gradient affect the position of the coastal sea front.

• 아동학회지
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• 제37권5호
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• pp.101-116
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• 2016

Objective: This study aimed to investigate how the eco-centered early childhood education by seasonal divisions influences the child's nature-friendly attitude and emotional intelligence. Methods: Forty 5-year-olds from 2 preschools in Gyeonggi were selected through convenience sampling and were divided into the experimental group (21) and the comparative group (19). The experimental group received eco-centered childhood education by seasonal divisions 2 or 3 times a week (33 in total). Pre-post data were collected on both groups and analyzed via t-test and ANCOVAs. Results: The key result was as follows: eco-centered childhood education by seasonal divisions influenced positively the nature-friendly attitude and emotional intelligence of children. Conclusion: Based on the result, it is recommended that eco-centered early childhood education be applied in childhood education and that relevant program be developed. Eco-centered education by seasonal divisions is meaningful in early childhood so that children can be harmonious with the nature. Furthermore, the study should be continued for the development of qualified eco-centered education.

• 한국해안해양공학회지
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• 제6권3호
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• pp.309-325
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• 1994

알라스카 만의 해수순환은 바람응력의 큰 계절적 변동에도 불구하고 큰 변화를 보이지 않는다. 그 역학적 원인을 알아보기 위해 일련의 수치모델 실험을 행하였다. 먼저, 관측밀도장으로부터 구한 진단모델 결과에 의하면 알라스카 난류의 계절적 변동은 거의 없으며, 여러 종류의 예보모델 결과에 의하면 해저지형과 경압성이 바람의 계절변동에 대한 해양반응에 영향을 미침을 보여준다. 모델 결과의 비교에 의해 경압해양의 바람의 계절변동에 대한 반응은 주로 순압성이며 순압 해수순환은 해저지형의 분만효과에 의해 약해지기 때문에 해수순간의 계절적 변동이 거의 나타나지 않는다.