• 한국지구과학회지
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• 제36권6호
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• pp.533-542
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• 2015

고창 해빈은 황해의 동편, 한국 서남해 연안에 위치하며, 북쪽에서 남쪽 방향으로 동호리, 광승리, 명사십리 해빈으로 구성된다. 고창 해빈은 대조차, 개방형, 직선형 해안, 모래 저질의 특징을 보인다. 본 연구는 고창 해빈에서 표층 지형 변화와 퇴적물 집적률의 연평균과 계절 특성을 연구하였다. 2014년 겨울(2월), 봄(5월), 여름(8월), 가을(11월)과 2015년 겨울(2월)의 5계절 동안, 3개 측선을 따라 총 315개 지점에서 지형 고도를 측정하였다. 해안선에 수직인 각 측선은 30 m 간격의 21 지점으로 구성된다. 고창 해빈의 2014년 연평균 집적률은 -0.081 m/yr로 침식이 우세하였다. 지역별 연평균 집적률은 동호리 해빈 -0.091 m/yr, 광승리 해빈 -0.051 m/yr, 명사십리 해빈 -0.10 m/yr로 나타났다.

• 한국해안해양공학회지
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• 제2권2호
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• pp.104-111
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• 1990

부산연안에서 태풍으로 인한 수위변화특성을 파악하고 수위예측을 위하여 태중 Thelma 통과 기간증 한국남해안에 위치한 6개 검조소의 조위관측자료와 기상자료를 분석하였다. 수치모델에 있어서는 해면기압의 공간분포로 인한 수위변화를 고려하였다. 폭풍해일(storm surge)의 계산결과 부산연안의 최대수위편차의 출현시각과 수위편차곡선은 가덕도의 조위실측치로부터 구한 수위편차곡선과의 상당히 유사한 결과를 나타냈다. 그러나 부산검조소 위치에서 조위실측치로부터 구한 수위편차곡선은 검조소가 수로에 위치한 관계로 일반적인 해일 곡선을 나타내지 못한다. 본 계산결과에 의하면 낙동강 하구역에서는 지형적인 영향으로 최대 2.5m 이상의 수위편차가 나타났으며, 그 밖의 해안에서는 약 60cm 전후의 수위편차가 나타났다.

• 자원환경지질
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• 제45권3호
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• pp.277-294
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• 2012

부산의 지역의 암석 종류에 따른 토양 내 라돈 농도의 시 공간적 변화 특성과 변화 요인에 대하여 연구하였다. 토양 내 라돈($^{222}Rn$)농도와 암석 및 토양의 모원소($^{226}Ra$,$^{228}Ra$ U, Th)의 농도를 부산지역 24개 지점에서 측정하였다. 모암과 토양 내 이들 모원소들의 분포와 거동 특징을 분석하고 라돈과의 상관성을 상세히 규명하였으며, 지형에 대한 영향도 평가하였다. 토양 내 라돈 농도 측정에는 두 가지 in-situ 방법(soil probe 방법과 지중매설튜브 방법)을 적용하여 측정의 정확성에 대하여 비교하였다. 토양 내 라돈의 공간적 분포는 모암의 암석 종류에 따른 U의 농도를 전반적으로 반영하여, 화산암에 비해 심성암에 높고, 산성암>중성암>염기성암 순으로 높은 변화양상을 보였다. 그러나 동일한 모암에서 유래된 토양내의 라돈 농도에서 큰 폭의 변화가 나타나며, 이는 라돈의 모원소인 U와 $^{226}Ra$의 암석과 토양에서의 현저한 방사능 비평형 결과이다. 따라서 토양 내 라돈 농도는 이들 모원소의 암석과 토양 내 농도와의 상관성은 매우 낮게 나타나며, 암석 내 농도에 비해 토양 내 농도와 더 높은 상관성을 보였다. Th과 $^{228}Ra$은 풍화작용과 토양 발달 특성에 따라 U와 지구화학적 거동 및 부하 특징을 달리하기 때문에, 동일한 모암에서 유래된 토양에서도 토양 특징에 따라 U와 현저히 다른 복잡한 농도 변화 양상을 나타내었다. 지형구배를 이루는 경사지의 동일 심도의 토양 내 라돈농도는 위치에 따라 차이를 나타내며, 모암을 같이하는 잔류토양(부산대 내 19개 지점)내에서는 소규모 지형 변화에 의해 토양 내 라돈 농도가 6.8~29.8Bq/L 범위로 변화하였다. 토양 내 라돈 농도는 토양 특성에 따라, 정반대의 계절적 변화 양상을 보인다. 지중매설튜브 방법이 soil probe 방법에 비해 더욱 정확히 토양 내 라돈농도를 측정할 수 있어, 토양 내 라돈의 시 공간적 변화 특성에 대한 분석에 매우 유용한 것으로 나타났다.

• Journal of Forest and Environmental Science
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• 제28권4호
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• pp.232-241
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• 2012

We investigated the relationship between vegetation type and soil carbon dynamics in even-aged alder (Alnus hirsuta) and Korean pine (Pinus koraiensis) plantations in central Korea. Both forests were located on the same soil parent material and occupied similar topographic positions. Soil $CO_2$ efflux in the two plantations was determined using a dynamic chamber method accompanied by measurements of soil moisture content and temperature. Mean soil temperature was similar in the two plantations, but mean soil water content was significantly higher in the alder plantation than in the pine plantation. In both plantations, seasonal patterns in soil $CO_2$ efflux exhibited pronounced variation that corresponded to soil temperature. Soil water content did not affect the seasonal variation in soil $CO_2$ efflux. However, in summer, when soil temperature was above $17^{\circ}C$, soil $CO_2$ efflux increased linearly with soil water content in the alder plantation. Estimated $Q_{10}$ was 3.3 for the alder plantation and 2.7 for the pine plantation. Mean soil respiration during the measurement period in the alder plantation was 0.43 g $CO_2\;m^{-2}\;h^{-1}$, which was 1.3 times higher than in the pine plantation (0.33 g $CO_2\;m^{-2}\;h^{-1}$). Higher soil $CO_2$ efflux in the alder plantation might be related to nitrogen availability, particularly the concentration of $NO_3{^-}$, which was measured using the ion-exchange resin bag method.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.32-32
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• 2019

The aim of this study was to provide basic guidelines for conservation and management of endangered plants in the national parks of Korea. Iris dichotoma Pall. (Iridaceae), which is a popular garden plant, is considered a second-class endangered species by Korean government and it is listed as a EN (Endangered) species in Red Data Book of Korea. We analyzed ecological conditions of I. dichotoma habitats based on vegetation properties and soil characteristics. This species which is known to inhabit in grassland adjacent to the ocean of lowlands slope and its population was located at an elevation of 8 m to 11 m. In the study sites, the mean of soil organic matter, total nitrogen and soil pH were 6.16%, 0.234% and 5.39 respectively. Additionally, the genetic variation and structure of three populations were assessed using ISSR (Inter Simple Sequence Repeat) markers. The genetic diversity of I. dichotoma (P = 59.46%, H = 0.206, S = 0.310) at the species level was relatively high. Analysis of molecular variance (AMOVA) showed 82.1% of the total genetic diversity was occurred in within populations and 17.9% variation among populations. Lastly, we developed predicted distribution model based on climate and topographic factors by applying SDMs (Species Distribution Models). Consequently, current status of I. dichotoma habitats is limited with natural factors such as the increase of the coverage rate of the herbs due to ecological succession. Therefore, it is essential to establish in situ and ex situ conservation strategies for protecting natural habitats and to require exploring potential and alternative habitats for reintroduction.

• 한국환경과학회지
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• 제15권6호
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• pp.527-532
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• 2006

The purpose of this study is to clarify the characteristic of urban heat island intensity in urban area formed at a basin. Thermal environments for basin-type cities are influenced by significant topographic relief winds. In this study, we analyzed the diurnal variations of the heat island intensity according to meteorological condition and season using AWS(Automatic Weather observation System) data in Daegu Metropolitan area for 1 year(3/April, 2003 $\sim$ 2/April, 2004). In this study, we defined the urban heat island intensity as the air temperature difference between two points, the downtown and the suburban area. The suburban area is located at valley mouth around the western tip of Daegu. The results are summarized as follows; 1. The maximum heat island intensity was recorded at early morning under the meteorological conditions, calm and clear 2. The heat island intensity was strong in the order of winter, fall, spring and summer. 3. The heat island intensity came out minus values in the afternoon. This phenomenon is known as a com mon for basin-type cities. 4. The heat island intensity was twice or more in clear and calm than not so.

• 한국작물학회지
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• 제50권4호
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• pp.276-280
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• 2005

Low temperature is one of the most severe abiotic stress factors limiting growth, productivity and distribution of winter cereals. Reliable field screening method, which can detect small differences in winter survival, is important for the effective selection and development of plants to identity superior cold tolerant winter cereal genotypes. This study was undertaken to provide improved screening method of winter hardiness in the field by increasing the accuracy in evaluating winter hardiness of barley (Hordeum vulgare L.). We introduced furrow in field screening of winter survival. By sowing the plants at the ridge and base, we could minimize the effect of topographic variation in a field by giving higher and lower level of stress at the same time. This method could be used by breeders to conduct accurate evaluation of winter hardiness by selecting the better treatment, which shows close to normal distribution, among the winter survival rate from the ridge, base and mean survival rate of the two in a screening field.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.634-639
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• 2003

It has been studied the flow near a rotating disk with surface topography. The system Ekman number is assumed very small, i.e., $E[{\equiv}\frac{\nu}{{\Omega}^{\ast}L^{\ast2}}]<<1$ in which $L^{\ast}$ denotes a disk radius, ${\nu}$ kinematic viscosity of the fluid and ${\Omega}^{\ast}$ angular velocity of the basic state. Disk surface has a sinusoidal topographic variation along radial coordinate, i.e., $z={\delta}cos(2{\pi}{\omega}r)$, where ${\delta}$ and ${\omega}$ are, respectively, nondimensional amplitude and wave number of the disk surface. Analytic solutions, being useful over the parametric ranges of ${\delta}{\sim}O$( $E^{1/2}$ ) and ${\omega}{\leq}O$ ( $E^{1/2}$ ), are secured in a series-function form of Fourier-Bessel type. An asymptotic behavior, when $E{\rightarrow}0$, is clarified as : for a disk with surface roughness, in contrast to the case of a flat disk, the azimuthal velocity increases in magnitude, together with the thickening boundary layer. The radial velocity, however, decreases in magnitude as the amplitude of surface waviness increases. Consequently, the overall Ekman pumping at the edge of the boundary layer remains unchanged, maintaining the constant value equal to that of the flat disk.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.424-437
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• 2003

This study was observed the variations in skin color, hydration, sebum content according to age groups at the forehead, both cheeks, and chin in 154 healthy Korean women subjects with aged 30 to 59. We selected four face sites (forehead, right cheek, left cheek, and chin) and measured with chromameter, corneometer, and sebumeter. All statistical analysis was performed on the computer software package SPSS 8.0. There was no significant difference of lightness between facial four regions in age groups but lightness showed to tend to age-related decrease on each regions. Redness and yellowness showed the highest values on chin and forehead respectively but there was no tendency to steady changes according to age variation. Both cheeks showed the highest hydration level and the lowest sebum content compared with forehead and chin in all age groups and there was tendency to age-related changes of sebum content on both cheeks. So we concluded there was decreasing tendency in lightness and sebum content according to the increase of age and there was no age-related change of skin hydration level at least in facial skin.(omitted)

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1997년도 학술발표회 논문집
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• pp.192-198
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• 1997

포화도의 공간적 변화인 지형지수를 계산하기 위한 다중흐름 알고리듬이 지형정보시스템인 GRASS와 연계되어 개발되었다. 본 연구는 소규모 농경지 배수구역에 대하여 적용하였다. 지하수위에 대한 타일 시스템의 영향이 DEM모형과 Laplace식에 의해서 효과적으로 고려될 수 있었다. 본 연구결과, 타일시스템을 고려한 유역은 타일시스템을 고려하지 않는 경우와 비교하여 높은 포화도를 가지고 있는 것으로 나타났으며, 예측된 riparian 유역은 실제의 유역조건과 잘 일치되고 있다. 본 연구에서는 지형지수를 산정함에 있어 타일 시스템의 효과를 고려해야 함을 제안하였다.