• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.844-847
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• 2006

In this work Topex/Poseidon altimeter data 1993 - 2002 were used. There are three altimetry tracks (one ascending and two descending) that cross Tatar Strait. The data were collected in the points of sub-satellite tracks with the step 0.25 degree. 10-years average values were calculated for each month. The seasonal sea level variations were compared with tide gauges data. The well expressed annual cycle (with maximum at July-August and the minimum at February-March) prevails in the Tartar Strait. However, the seasonal variations expressed much weakly in both the altimetry track points and Kholmsk - Nevelsk tide-gauges that locate close to La Perouse Strait because of Okhotsk Sea influence. The sea level slopes between the Sakhalin Island and the continent coasts were analyzed in different seasons. We found that sea level increases near Sakhalin coast in spring and summer that corresponds to the northward flow. In autumn, otherwise, the sea level decreases near Sakhalin Island that corresponds to southward current. This result is verified by the CTD data gathered on the standard sections. Well-expressed upwelling is observed near coastline of Sakhalin Island in fall season. This phenomenon is caused by the northerly and the northwesterly wind which are typical for cold season.

• Journal of Astronomy and Space Sciences
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• 제14권1호
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• pp.109-116
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• 1997

중간권 계면(고도 85km)은 중간권과 열권의 경계면으로 활발한 유체역학적 운동과 화학반응에 의한 대기 발광현상이 일어나는 흥미로운 곳이다. 그러나 직접 측정의 어려우으로 그 동안 많은 연구가 있지 못하였다. 본 연구에서는 중간계면 87km 고도에서 발생하는 수산기의 대기발광(843mm)을 지상 파브리-페로 간섭계로 측정하여 도플러 온도와 바람 속도를 측정하였다. 2년간에 걸친 장기간의 연구로 이 곳의 계절적 온도 변화가 지상의 온도 변화와 반대 경향인 것을 확인할 수 있었고, 남북.동서 방향의 바람 속도는 각각 연 1회, 연 2회 변화하는 것을 밝혀내었다. 이러한 온도와 바람의 계절적 변화는 대규모 반구간 대류 운동의 결과로 여겨진다.

• 대한원격탐사학회지
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• 제16권2호
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• pp.117-133
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• 2000

We studied the sea level variations at Kerguelen island in the South Indian Ocean with ARGOS data and meteorological data during about 1 year(May 1993~April 1994) through using filter, spectral analysis, coherency and phase, and found characteristics for the two oceanic signal levels(detided oceanic signal level, h$_{detided}$ and seasonal oceanic level, h$_{corr.ib}$). The forms of atmospheric pressure variations are good agreed to between ARGOS data and meteorological data in the observed periods. This Kerguelen area shows the inflow of an air temperature(gain of a radiant heat) into the sea water and the stagnation of high atmospheric pressure bands in summer, and the outflow of a sea water temperature(loss of sensible and latent heat) toward the atmosphere and the stagnation of low atmospheric pressure bands in winter. The seasonal difference of sea level between summer and winter is about 1.6cm. Both the detided oceanic signal level(h$_{detided}$) variation and the inverted barometer level(h$_{ib}$) variation have a strong correlation for T>1day period bands. The characteristics of h$_{detided}$ variation are not decided by the influence of any meteorological distributions (atmospheric pressure), but the influence of other factors(bottom water temperature) for T>2days periods bands. h$_{corr.ib}$ plays a very important role of sea level variation in the observed periods (especially T>about 180days period bands).

• 한국환경과학회지
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• 제16권10호
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• pp.1157-1167
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• 2007

In an effort to interpret the characteristics of fine particle concentrations in Busan, time variations of hourly monitored concentrations $PM_{10}$ (Particulate Matter with aerodynamic Diameter ${\le}10\;{\mu}m$) in Busan are analyzed for the period from 2000 to 2005. The characteristics of aerosol second generation formation process is also interpreted qualitatively, by using the statistical analysis of the meteorological variables including temperature, wind speed, and relative humidity. The result shows some significant annual, seasonal, weekly and diurnal variations of $PM_{10}$ concentrations. In particular, seasonal(i.e., spring) variations are governed by frequency of yellow sand events even for the non-yellow sand cases where yellow-sand days are eliminated in our analysis. However, in seasonal variation, summer season predominate lower $PM_{10}$ concentrations due to the frequent precipitation, and weekly and diurnal variations are both found to be reflecting the emission rate from traffic amount. Correlation coefficients between $PM_{10}$ concentration and meterological variables for non-yellow sand days show overall negative correlation with visibility, wind speed, cloud amounts, and relative humidity. However for non-precipitation days, during non-yellow sand period positive correlation are found clearly with relative humidity, suggesting the importance of secondary aerosol formation in Busan that can be achieved by both homogeneous aerosol formation and heterogeneous transformations resulting from hygroscopic aerosol characteristics.

• 생약학회지
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• 제24권1호
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• pp.54-57
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• 1993

The seasonal variations of five biflavones from Ginkgo biloba leaves from May to November were investigated by a reversed phase HPLC method. The total amount of biflavones was increased with time to reach its maximum in yellow autumnal leaves. Each biflavone showed a similar tendency. It increased rapidly about 3.1-fold from May to June and thereafter gradually increased about 2.5-fold. The ratio of each biflavone content to the total amount of biflavones was in the order of as follows: isoginkgetin>sciadopitysin>bilobetin>ginkgetin>amentoflavone.

• 한국환경생태학회지
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• 제34권1호
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• pp.55-62
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• 2020

이 연구는 강원대학교 학술림 내의 산지계류를 대상으로 2년간(2017~2018)의 현지 모니터링에 기초하여 수온과 강우, 유량 및 기온 등 환경인자간의 관계를 분석하고, 계절별 산지계류의 수온변화 예측기법에 대하여 검토하였다. 동절기를 제외한 봄, 여름 및 가을철로 구분하여 단계적 다중선형회귀분석을 실시하였으며, 계절별 산지계류의 수온변화에 미치는 환경인자의 영향을 분석하였다. 그 결과, 산지계류의 일평균 수온은 봄철 6.9~17.7℃로 기온과 유의적 관계를 나타내었고, 여름철 12.2~26.3℃로 기온, 유량과 유의적 관계를 나타냈으며, 가을철 3.6~19.3℃로 기온 및 유량과 유의적 관계를 나타내는 등 계절별로 산지계류의 수온에 미치는 영향인자는 다르게 나타났다. 다중선형회귀식은 봄철 (0.553×기온)+(0.086×유량)+4.145(R²=0.505; p<0.01), 여름철 (0.756×기온)+(-0.072×유량)+2.670(R²=0.510; p<0.01), 가을철 (0.738×기온)+(0.028×강우)+2.660(R²=0.844; p<0.01)이었다. 도출된 모든 회귀식의 결정계수(R²)는 기온만으로 예측한 경우보다 높게 나타났고, 봄철에서 가을철로 갈수록 증가하였다. 향후 정밀도 높은 산지계류의 수온변화 예측을 위해서는 지속적인 현지 모니터링과 함께 시·공간적 데이터의 확보가 중요하다고 판단된다.

• 대기
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• 제17권4호
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• pp.421-433
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• 2007

We have investigated the seasonal characteristics of surface turbulent fluxes observed at Ieodo Ocean Research Station from 2005 to 2006. Both 10Hz and 30 minutes flux data are quality controled, and tilt correction is performed in 10Hz data before quality control. The turbulent fluxes of open sea shows clear seasonal variations, though diurnal variations are barely shown. The seasonal ratio of stable and unstable conditions are closely related to the temperature difference between sea surface and air. In stable and semi-stable condition, latent and sensible heat fluxes have very small values without any relationship with wind speed. Though friction velocity shows slightly increasing trend with wind speed, it has many outliers. In unstable condition, turbulent fluxes increased with wind speed. Especially, latent heat flux increased rapidly during DJF. The latent heat flux at high wind speeds is more scatter.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1134-1138
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• 2006

Forest tree leaves (12 different species) of semi hilly arid region of Punjab State were collected at 30-day interval throughout the year to assess the seasonal variations in tannin profile. Tannins were extracted and fractionated from fat free samples and data were analyzed statistically by $12{\times}12$ factorial design. The leaves of Anogeissus latifolia had the highest (p<0.05) concentration of total phenols (17.4%), net (15.9%) and hydrolysable (16.9%) tannins, followed by leaves of Acacia nilotica. Majority of the tree leaves selected had moderate levels (2-5%) of net tannins. Leaves of Carrisa had the highest (p<0.05) concentration of condensed tannins (CT), whereas the leaves of Anogeissus had the lowest (p<0.05) concentration of condensed tannins. The protein precipitable phenols (PPP) corresponded well with the net tannin content present in different tree leaves. Seasonal variation data revealed that in summer, net tannins and PPP decline in leaves of Bauhinia and Zizyphus whereas the net tannin content of Anogeissus and that of Carrisa increased during summer. The CT and PPP content in the leaves of Pheonix, Leucaena, Zizyphus and Ougenia increased in winter till spring season. Tree leaves generally had higher concentration of HT during summer months. It was concluded that leaves of leaves of A. nilotica, A. latifolia and L. leucocephala could serve as an excellent alternate feed stuffs for ruminants. However, leaves of Phoenix, Carrisa, Bauhinia and Dodonea should be avoided.

• Ocean and Polar Research
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• 제37권2호
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• pp.127-140
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• 2015

A continuous series of 60 snow samples was collected at a 2.5-cm interval from a 1.5-m snow pit at a site on the Styx Glacier Plateau in Victoria Land, Antarctica, during the 2011/2012 austral summer season. Various chemical components (${\delta}D$, ${\delta}^{18}O$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^2-}$, $NO_3{^-}$, $F^-$, $CH_3SO_3{^-}$, $CH_3CO_2{^-}$ and $HCO_2{^-}$) were determined to understand the highly resolved seasonal variations of these species in the coastal atmosphere near the Antarctic Jang Bogo station. Based on vertical profiles of ${\delta}^{18}O$, $NO_3{^-}$and MSA, which showed prominent seasonal changes in concentrations, the snow samples were dated to cover the time period from 2009 austral winter to 2012 austral summer with a mean accumulation rate of $226kgH_2Om^{-2}yr^{-1}$. Our snow profiles show pronounced seasonal variations for all the measured chemical species with a different pattern between different species. The distinctive feature of the occurrence patterns of the seasonal variations is clearly linked to changes in the relative strength of contributions from various natural sources (sea salt spray, volcanoes, crust-derived dust, and marine biogenic activities) during different short-term periods. The results allow us to understand the transport pathways and input mechanisms for each species and provide valuable information that will be useful for investigating long-term (decades to century scale periods) climate and environmental changes that can be deduced from an ice core to be retrieved from the Styx Glacier Plateau in the near future.

• 한국습지학회지
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• 제17권3호
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• pp.311-319
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• 2015

국토의 균형적인 개발과 수계 수질 보호를 목적으로 한국 정부는 농촌 지역 하수도 보급 사업을 진행하고 있다. 본 연구는 농촌 지역 하수도 보급 사업의 하나인 A 하수종말처리장의 연간 운전결과를 분석하였다. 농촌 지역 하수종말처리장 유입 하수 농도는 계절에 따라 변화하며, 여름철에 가장 낮은 것으로 나타났다. 계절 변화에 따른 생물반응조의 처리 효율은 유기물질에 비해 영양염류가 계절에 따라 처리 효율의 변화가 큰 것으로 나타났으며 겨울철에 가장 낮은 것으로 나타났다. 또한 영양염류는 체류시간과 F/M ratio에 대해 유기물보다 민감하게 반응한 결과를 보였다. 농촌 지역 하수종말처리장 공법 선정 시 계절에 따라 변화하는 유입 하수의 특성을 고려해야 한다. 또한 겨울철 영양염류의 안정적인 처리 효율을 위한 유지관리가 필요하다.