• 한국해양학회지
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• 제29권3호
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• pp.258-268
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• 1994

황해 남부해역에서 1993년 4월 25일부터 30일까지 안정동위원소인 /SUP 15/N 질 산염과 암모니아를 이용하여 질소 신생산과 재생산을 측정하였다. 질소생산은 155∼ 688 mg N m/SUP -2/d/SUP -1/의 값을 보였는데 이는 중영양 또는 부영양 해역의 특성 이다. 탄소량으로 한산하면 C:N Redfield비 5.7:1을 가정하였을 때 881∼3909 mg C m/SUP -2d/SUP -1/에 해당된다. 기초생산 중 신생산이 차지하는 비율인 f-ratio의 범 위는 0.12∼0.26으로 기초생산의 74∼88%가 수층 내에서 순환되는 암모니아에 의하여 유지된다는 것을 시사한다. 이러한 낮은 f-ratio 값은 빈영양 또는 중영양 해역의 특 징이다. 영양염의 농도는 예상했던 바와 달리 이 해역에서 의 조사기간에는 생산성을 조절하는 중요한 요인이 아니었으며, 정점간 생산성의 차이는 수괴에 따른 생물 현존 량의 차이에 주로 기인하는 것으로 보인다.

• 한국태양에너지학회 논문집
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• 제29권6호
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• pp.81-87
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• 2009

The purpose of this study is to evaluate of the outdoor thermal environment by building scale and block type as variable factors. In this study, 18 cases of office in central business district that have different condition are compared about their surface temperature, HIP(Heat Island Potential), and MRT(Mean Radiant Temperature). They are simulated with 3-dimension numerical simulation software named Hoyano-model. The output results contain visualized distribution chart and numerical data. The results of evaluation are as follows. (1)The surface temperature of the building becomes higher as building coverage ratio is higher but floor area ratio is lower. In same conditions, unified block type is maximum $3.2^{\circ}C$ higher than divided block type. (2)HIP shows different daily pattern as block type. During daytime, divided block type is much higher than unified block type but after sunset, it is changed. (3)MRT shows different distribution pattern as sunlight moves expecially at noon. (4)As the results of this study, cases that have high floor area ratio condition show lower surface temperature by tendency to stay low indoor temperature in office building and big rate of windows on building surface.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.728-731
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• 2006

Ground subsidence near abandoned underground coal mines has become a serious social problem in Korea. The purpose of this study is to perform a comparative analysis between the ground subsidence area and the electrical resistivity measured by field survey at Samcheok City. A raster database composed of ground subsidence areas and electrical resistivity data was constructed for GIS. To analyze correlation between the two constructed raster datasets, we used a frequency ratio model. The results show that low and high electrical resistivity anomaly zones coincide with the existing subsidence areas. We infer that the high anomaly zone means saturated and low anomaly zone means vacant. It suggests that electrical resistivity might be a useful factor for analyzing ground subsidence hazard zone.

• Bulletin of the Korean Chemical Society
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• 제18권12호
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• pp.1249-1256
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• 1997

Single phase La1-xSrxCoO3 (x≤0.2) was synthesized as a uniform sized 100 nm particulates with relatively high surface area of 20-30 m2/g, at low temperature (≥600 ℃), from a polymeric gel precursors prepared by using poly(vinyl alcohol) as homogenizer. No minor phase developed during the crystallization when polymer/metal mole ratio was higher than 3. As the polymer/metal mole ratio was raised in the gel, the amount of carbonaceous residues in the amorphous solid precursor prepared by heating the gel at 300 ℃ increased. Most of the residues were eliminated by exothermic thermal decomposition around 400 ℃. The amount of residual carbon (less than 1%) left in the crystalline La1-xSrxCoO3 decreased as more polymer was used, eliminating detrimental effect which might be posed by using large amount of organic homogenizer. The crystal structure of La1-xSrxCoO3 synthesized at temperature lower than 800 ℃ was observed to be shifted from rhombohedral to more symmetric cubic. The structure shifted back to rhombohedral as the cubic sample was annealed at 1000 ℃.

• 천문학회보
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• 제45권1호
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• pp.58.2-58.2
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• 2020

We present a method for determining the abundance ratio of nitrogen to iron ([N/Fe]) from low-resolution (R~2000) stellar spectra from large spectroscopic surveys such as Sloan Digital Sky Survey (SDSS) and Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). The basic idea of the method is to match a grid of synthetic spectra with an observed spectrum in the CN band region around 3883 Å. To calibrate our estimate of [N/Fe], we make use of the giants observed in Apache Point Observatory Galaxy Evolution Experiment (APOGEE), which are also observed in the SDSS. This method will be applied to the Galactic halo stars to determine [N/Fe], and the measured nitrogen abundance ratios will be used to investigate the C-N anti-correlation, which is observed in globular clusters, to trace their origin with their kinematic properties.

• 한국지리정보학회지
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• 제17권4호
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• pp.129-143
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• 2014

본 연구는 경상남도 창원시를 대상으로 도시 침수문제를 개선하기 위해 GIS 분석을 활용하여 침수 취약성을 평가하였다. 평가 요인은 물순환 면적률과 표면 유출특성, 강우량 분포이며, GIS 프로그램을 활용하여 평가요인에 대한 정보 구축과 침수 취약성 평가를 분석하였다. 물순환 면적률과 표면 유출특성은 도시지역에서 취약하였다. 강우량 분포는 북쪽의 농촌지역에서 많았다. 침수 취약성 평가 결과 북쪽의 농업지역과 산림지역에서 낮았다. 반대로 도시지역은 불투수 재질로 포장되어 있어 취약성이 높았다. Hotspot 공간군집분석을 이용하여 침수 취약지역의 밀집도를 분석한 결과는 도시지역에서 매우 높은 밀집도를 보였다. 그리고 이들 지역은 대부분 하천의 하류에 위치해 있어 실제 침수가 빈번히 발생하는 것으로 확인되었다. 따라서 본 연구의 침수 취약성 평가는 도시 및 환경계획 차원에서 침수 피해를 예방하기 위해 투수성 포장재질의 조성과 빗물관리 시설의 설치위치를 선정하는데 효율적인 자료로 활용 가능할 것으로 판단된다.

• 한국대기환경학회지
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• 제27권5호
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• pp.558-568
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• 2011

Hazardous volatile organic compounds (HVOCs) have been increasingly getting concern in urban air chemistry due to photochemical smog as well as its toxicity or potential hazards. In this study, we investigated their concentrations and the properties in tunnel, urban roadside and residential area. As a result, among 36HVOCs measured in this study, BTEX (benzene, toluene, ethylbenzene, xylene) and dichlorodifluoromethane, 1,2,4-trimethylbenzene, trichlorofluoromethane were detected above the concentration of $1{\mu}g/m^3$ in every sampling site and the most abundant compound was toluene. The other compounds were detected at trace level or below the detection limit. In addition, we found that three CFCs (chlorofluorocarbons), such as CFC-12, CFC-11, CFC-113, were persistently detected because of the emission in the past. Toluene to benzene ratio (T/B) at tunnel and roadside were calculated to be 4.3~5.3 and at residential area 15.4, suggesting that the residential area had several emission sources other than car exhaust. The ratio of X/E (m,p-xylene to ethylbenzene) ratio was calculated to be 1.8~2.1 at tunnel, 1.7 at roadside and 1.2 at residential area, which means this ratio reflected well the relative photochemical reactivity between these compounds. Good correlation between m,p-xylene and ethylbenzene ($r^2$ > 0.85) were shown in every study sites. This indicated that correlation between $C_2$-alkylbenzenes were not severely affected by 3-way catalytic converter. In this study, it was demonstrated that the concentration of benzene was very low, compared with national air quality standard (annual average of $5{\mu}g/m^3$). Its concentration were $2.52{\mu}g/m^3$ in roadside and $1.34{\mu}g/m^3$ in residential area. We thought this was the result of persistent policy implementation including the reduction of benzene content in gasoline enforced on January 1, 2009.

• Journal of Plant Biology
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• 제12권2호
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• pp.28-42
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• 1969

Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

• Journal of the Korean Wood Science and Technology
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• 제36권6호
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• pp.69-76
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• 2008

탄화온도별로 제조한 신갈나무(Quercus mongolica Fischer)목탄과 낙엽송(Larix leptoepis)수피탄에 의한 유해가스 흡착성능 평가를 하여 본 결과, 탄화온도가 증가하면 비표면적과 탄소함량이 증가하는 경향이 있으나, $600^{\circ}C$이상의 온도에서는 상승폭이 둔화하였다. 또한 신갈나무탄과 낙엽송수피탄에 의한 유해가스 제거율 차이는 뚜렷하지는 않았으나, 탄화온도는 가스흡착성능에 큰 영향을 주는 것으로 나타났다. 즉, $300^{\circ}C$에서 탄화한 저온 목질탄화물은 목탄 또는 수피탄의 종류에 관계없이 50% 이하의 매우 낮은 악취가스 및 VOC 물질 제거율을 나타낸 반면, $600^{\circ}C$이상의 고온 탄화물은 목질의 종류에 관계없이 악취물질인 트리메틸아민, 메틸메르캅탄, 황화수소의 제거율과 VOC물질인 벤젠, 톨루엔, 자일렌 제거율이 거의 100%를 나타낼 정도로 높았으며, 흡착 10분 이내에 흡착평형에 이를 정도로 빠른 흡착성을 나타내었다. 한편 아세틸렌이나 $SO_2$, $NO_2$ 가스 제거율은 고온탄화물이라도 흡착 4시간 후인 흡착평형이 이루어지더라도 40% 이하로 매우 낮아 가스 종류에 따라서 흡착거동에 차이가 있었다. 이와 같이 탄화온도와 가스 종류에 따라 흡착성능이 달라지는 것은 비표면적과 같은 물리적인 요인뿐만 아니라 목탄의 관능기 종류 및 양에 의한 화학적 변화가 영향을 미치는 것으로 판단되며, 화학적 요인에 대한 구명이 필요할 것으로 생각된다.

• 한국환경생태학회지
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• 제26권5호
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• pp.801-811
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• 2012

본 연구는 도시공원의 토지피복 및 식재구조에 따른 온도 영향요인을 규명하는데 목적이 있다. 성남시 분당구 중앙공원을 대상으로 전 지역에 대한 토지피복 및 식재현황을 파악하였으며 30개의 조사구를 설정하여 정밀 토지피복 및 식재구조를 파악하고 온도는 10회 반복 측정하였다. 온도 영향요인은 토지피복유형, 식재유형, 층위구조, 녹지량(녹피율, 녹지용적계수)을 선정하여 실측 온도와의 통계분석을 실시하였다. 토지피복유형, 식재유형, 층위구조와 실측 온도와의 분산분석 결과, 토지피복유형에서 목본 식재지는 저온역으로 초지와 포장지는 고온역으로 구분되었다. 식재유형은 침엽수 및 활엽수 식재지는 저온역으로, 초지와 포장지는 고온역으로 구분되었다. 층위구조는 교목층과 교목층+하부식재 유형은 저온역으로, 초지와 포장지는 고온역으로 구분되었다. 녹지량과 실측 온도와의 상관관계 분석 결과 녹피율과 녹지용적계수는 모두 실측 온도값과 고도의 음(-)의 상관관계가 인정되었다. 녹지량과 실측 온도와의 회귀모형에 의하면 녹피율은 1% 증가할 때마다 $-0.002^{\circ}C$, 녹지용적계수는 $1m^3/m^2$ 증가할 때마다 $-0.122^{\circ}C$의 온도저감 효과가 있을 것으로 예측되었다.