• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.105-113
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• 1977

In this paper have been examained the relation of tssk performance to body size. the variation of venation of males, sex ratio, breeding by forms of worker's pupae and structure by forms of workers's colony to nest size in polymorphism of polydomous red wood ant, Formica rufa truncicola var. yessoensis Forel in Korea. 1. The workers are classified into three forms, in which small form mainly performs itself the task of nursing in the nest and the visit to aphid from the outside of the nest, medium and large form mainly do not only the stinct of prey carrying from the outside of the nest and nest structure, but the task of protecting colony of outside. But the small forms visiting to aphid is not always fixed but seems to be changed with season. 2. The variation forms of venation of males are fourteen, generally, they have various variations of the discoidal. 3. Generally, sex ratio of Formica rufa truncicola var. yessoensis Forel is the same proportion, but it seems that there are some difference according to its characteristic of colony in each nest and polydomous colony structure in its habitat. 4. In summer season the medium form makes a colony in high proportion without any relations with the size of nest but. during hibernation, small form coasists in small nest, medium in medium nest and large in large nest. And so the structure of worker's colony by forms according to their nest size seems to be changed with season.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.11-21
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• 1996

Comparing hibernation with active periods, the regional distribution and relative frequencies of gastrointestinal endocrine cells were studied immunohist-ochemically in the GITs of the Rana dybowskii. Six kinds of endocrine cells were identified in this study. In this study, several novel findings were emerged: in hibernation period, the perdominant presence of immunoreactive cells; the widely distributional regions of glucagon-, Gas/CCK- and BPP-immunoreactive cells; the intense reaction of immunostaining against the antiserum; and the existence of 5-HT- and somatostat-in-immunoreactive cells in upper regions of the fundic glands. These results suggest that the gastro-entero-endocrine cells in hibernation period synthesize continuously its gut hormones and accumulate in their cytoplasms.

• The Korean Journal of Ecology
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• v.21 no.5_1
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• pp.457.2-486
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• 1998

Ecological success of introduced species is frequently attributed to the reproductive characters of those species. We examined the relationship between both flowering season and plant size and reproductive characters in two introduced species of Taraxacum, e.g., T. officinale and T.laevigatum. Seventy six plants of T. officinale and 23 plants of T. laevigatum were randomly tagged from a population at the sungshin Women's University in April of 1997. The size and number of vegetative characters such as rosette diameter, leaf number, and the largest leaf length and width were measured for each plant at the onset of flowering. The infructescence was collected continually from each plant before seed dispersal from April to August of 1997. The number of infructescence per plant, and seed number and total seed weight per infructescence were measured. Mean individual seed weight per infructescence was also obtained. T. officinale possessed larger sized, but smaller number of, leaves than T. laevigatum, thereby resulting in no significant difference in total leaf area. There was a trend that vegetatively larger plants in both of these species produced reproductive characters larger in size or greater in number, except for seed number and total seed weight per infructescence in T. laevigatum. All reproductive characters examined in T. officinale decreased toward the end of flowering season. In T. laevigatum, infructescence number per plant also declined during a flowering season: however, mean seed number per infructescence increaed toward the end of flowering season with no significant seasonal change in the total seed weight per infructescence. T. officinale produced on average about twice as many seeds per plant as T. laevigatum during a growing season. These two Taraxacum species produced quite small seeds in size compared to the endemic species, exhibiting a far better dispersal ability of introduced species. These data demonstrate that most reproductive characters decline in size and number in both species during a long flowering period, but the two species appear to employ different strategies to achieve reproductive success in disturbed habitats.

• Journal of Climate Change Research
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• v.2 no.4
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• pp.269-281
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• 2011

In this review, numerical model results from global and regional climate models are introduced to regional detailed climate changes over East Asia and Korea. In particular, regional climate change scenarios in this region, which are created by several research groups in Korea based on Special Report on Emissions Scenarios (SRES) of IPCC 4th assessment report are introduced and characteristics of the scenarios are investigated. Despite slight differences in intensity, all scenarios reveal prominent warming over the Korean peninsula in future climate. Changes in precipitation amount vary with given scenarios and periods, but the frequency and intensity of heavy precipitation generally tend to increase in all scenarios. South Korea except for mountainous regions is expected to change into subtropical climate in future, which accompanies distinct changes in ecosystems and seasons.

• Journal of the Korean Wood Science and Technology
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• v.31 no.2
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• pp.38-44
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• 2003

This study was carried out to evaluate the feasibility of using HDF as surface panels as well as core materials for flush door manufacturing. Six core constructions were developed and applied to manufacture door specimens and conventional skin door specimen was also manufactured for comparison. Door specimens were tested under changing interior environmental condition for 3~4 months during winter and summer seasons. During the test period, deformation of doors were measured weekly, and temperature and relative humidity of testing area were also recorded. From this study, it was concluded that HDF can be used to manufacture quality flush doors and core construction developed in this study showed good quality compared to conventional skin door. Deformation of doors increased as temperature and relative humidity of the surrounding environment increased. Flush doors generally showed less deformation than skin doors, and evaluated to be stable and good quality when compared to skin door.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.12
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• pp.1756-1761
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• 2021

Although the COVID-19 outbreak that occurred in Wuhan, Hubei around December 2019, seemed to be gradually decreasing, it was gradually increasing as of November 2020 and June 2021, and estimated confirmed cases were 192 million worldwide and approximately 184 thousand in South Korea. The Central Disaster and Safety Countermeasures Headquarters have been taking strong countermeasures by implementing level 4 social distancing. However, as the highly infectious COVID-19 variants, such as Delta mutation, have been on the rise, the number of daily confirmed cases in Korea has increased to 1,800. Therefore, the number of cumulative confirmed COVID-19 cases is predicted using ARIMA algorithms to emphasize the severity of COVID-19. In the process, differences are used to remove trends and seasonality, and p, d, and q values are determined and forecasted in ARIMA using MA, AR, autocorrelation functions, and partial autocorrelation functions. Finally, forecast and actual values are compared to evaluate how well it was forecasted.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.198-198
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• 2020

기후 내적 변동성(Climate Internal Variability, CIV)은 기후를 이해하는 데 중요한 역할을 하며 기후예측에 있어 주요 불확실성 원인들 중 하나이다. 본 연구는 다양한 이산화탄소 배출 시나리오에 대해 CIV와 기후학적 평균(Climatological Mean, CM)을 추정하는 것을 목표로 한다. 확률론적 날씨생성기(Stochastic Weather Generator)를 이용하여 국내 40개 기상 관측소에 대해, 30년에 해당하는 시단위 시계열 100개 앙상블을 생성하였다. CIV는 Detrend 방법과 Differenced 방법을 이용하여 추정되었으며, noise 계산값과 비교하였다. 그 결과, CIV 값과 noise 값들 사이의 correlation이 매우 높았으며, 제시된 방법론이 신뢰할 수 있음을 검증하였다. 국내 40개 지역에 적용하여 계산된 CIV와 CM의 주요 결과는 다음과 같다. (1) 국내의 대부분의 지역에 있어 평균적으로 CM과 CIV는 미래에 증가할 것이며, 그 증가 정도는 RCP 8.5의 경우와 먼 미래END(2071-2100년) 기간에서 더 커질 것이다; (2) CM과 CIV의 미래 변화의 특성은 강수의 특성 지수에 따라 다르다. 강수량의 양을 나타내는 3개의 지수(총 강수량, totPr, 일 최대 강수량, maxDa 및 시간당 최대 강수량, maxHr)와 강수량의 발생일수를 나타내는 지수(무강우 일수, nonPr)의 특성은 크게 다르다. (3) CIV와 CM의 변화 요인들 사이의 관계를 조사하면 maxDa와 maxHr에 대해서는 그들 사이에 높은 상관관계가 있지만 다른 지수에는 그렇지 않다. (4) 국내에서 CIV 값이 공간적으로 변동성이 큰 경우는 계절적으로 여름이며, 이는 totPr 및 maxDa에서만 유효하다. 시단위 시계열 앙상블을 생성하여 추정된 기후내적변동성 정보는 기후 변화의 영향을 평가하고 적절한 적응 및 대응 전략을 개발하는 데 도움이 될 것이다.

• Journal of the Korean earth science society
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• v.21 no.2
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• pp.128-136
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• 2000

To understand the variation and transport pattern of suspended matters, salinity, tidal current and suspended matters in semiclosed Muan Bay have been monitored during winter and summer. The suspended matters show considerably seasonal variations with low concentration and homogeneity in the water column during winter season, but with high concentration and layering during summer season. Particularly, during summer season, the freshwater and the suspended matters influxed by the gate operation of the Youngsan River sea-dike are transported northward in accordance with the would flow into the inner-bay by relaxed flood currents after the construction of sea-dike and sea-walls in the Mokpo coastal zone. But, in the south bay-mouth, those matters outflow through the bay-mouth, resulting from tidal ebb dominance and asymmetry in the west bay-mouth. The residual suspended matter flux is much higher in the south bay-mouth(-0.0955kg/m ${\cdot}$ sec) than that of west bay-mouth(0.0078kg1m ${\cdot}$ sec). Accordingly, The Muan Bay is interpreted as erosion-dominated environments, and the erosion somewhat progresses in the intertidal flat of the bay.

• Korean Journal of Ecology and Environment
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• v.34 no.4 s.96
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• pp.277-284
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• 2001

Since a substantial part of the total planktonic primary production is due to the activity of the picoplankton, seasonal change of chlorophyll a in the picoplankton, nanoplankton and microplankton was determined at four locations in Daechung Reservoir from September in 1998 to September in 1999. Chlorophyll a concentration (<$200\;{\mu}m$) was $0.7{\sim}36.9\;{\mu}g/l$ In TAE (Taejeon site), $0.5{\sim}23.5\;{\mu}g/l$ in MAN (Man site), $1.9{\sim}20.1\;{\mu}g/l$ in HOE (Hoenam site), and $0.5{\sim}17.4\;{\mu}g/l$ in DAM (Dam site). Generally it was observed the highest concentration of chlorophyll a was in September and the lowest in April to June. The relative contribution of chlorophyll a of each fraction was changed dramatically through the year. Relative contribution of chlorophyll a of microplankton was high from June to October, and low in March in all locations except HOE. However chlorophlyll a concentration of picoplankton fraction was $2.0{\sim}24.3%$ of total chlorophyll a (<$200\;{\mu}m$) through the year and did not show any dramatic changes at all locations.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.291-300
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• 2010

This study was carried out in the Chungnam National University grassland experimental field from October, 2007 to December, 2009 in order to find out the growth characteristics of the wildflowers, the seasonal anthesis distribution of the wildflowers and the botanical composition of the wildflowers which were altogether composed of 50% sheep fescue and 50% wildflowers. The experimental species contained 34 species in total consist of sheep fescue (fundamental turfgrass), 4 native wildflowers, and 29 introduced wildflowers belonged. At the time of the anthesis of the wildflowers, the average length was 30.0 cm one year later and 35.6 cm two years later. They bloomed out into ten colors, but into simplified colors during August, September, and October. The peak of the blooming was May and June and blooming pattern leant from August to October. Especially, at the age of two (2009) the color, seasonal distribution, and consistency emerged as problems owing to the reduction of annual wildflowers after winterization. The annual botanical composition of wildflowers, sheep fescue, and weed came to 28%, 55%, and 17% each one year later (2008) and 24%, 60%, and 17% each two years later (2009). Based on this result, cultivating wildflower grassland (sheep fescue 50% + wildflowers 50%) is the proper method for making up such flatlands as parks and riversides in a short period (one year) for the purpose of commanding a fine view.