• 한국제4기학회지
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• 제24권2호
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• pp.13-21
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• 2010

무안 피서리유적은 최근 서남해안 일대에서 확인되고 있는 구석기시대 유적들에 대한 의미 있는 자료들을 제공하고 있다. 무안 피서리유적에 대한 층위 및 지질학적 분석결과는 토양쐐기의 특성이 토양의 굳기나 토양내부의 성분 함량 및 고지표면의 기복에 따라 차이가 있을 수 있다는 것을 지시해주고 있다. 피서리유적에서 중기 구석기 늦은 단계 또는 후기 구석기 이른 단계의 석기들이 함께 출토되었는데 이는 이들 석기가 산출되는 문화층이 최대 빙하 발달시기 이후에 형성되었다는 것을 고려해 볼 때 활발한 침식과 재퇴적에 의해 여러 시기의 유물이 함께 재퇴적된 결과일 가능성을 지시해 주고 있다. 이번 연구를 통해 구석기 유물의 분포와 토양쐐기와 같은 토양층의 특성은 고지표면의 기복 및 기후환경과 같은 자연환경적 조건에 의해 영향 받을 수 있다는 것을 고찰하였다.

• 한국조경학회지
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• 제22권1호
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• pp.85-100
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• 1994

This study was to analyze the relationship between the community or species and environmental variables of the vegetation landscape in Naejangsan National Park. The analysis was performed by the ordination of DCA and CCA. The study was to compare and analyze the species composition status by the layer and the growth characterisics of the following vegetations ; Torreya nucifera community, Quercus variabilis - Acer palmatum community, Q. variabilis community, Q. variabilis - Sasa purpurascens community and Daphniphyllam macropodum community. The results are as follows; 1. The result of the study on the relationshkp between the stand scores of DCA ordination and environmental variables showed that the soil pH, the ammount of AV-P2O5 and the ammount of C.E.C. tend to increase while Pinus densiflora community changes to Q. variabilis - Q. serrata community and finally Carpinus laxiflora species community siginigicantly. The relation between the stand scores of CCA ordination and several enviromental variables suggested that the species of C. laxiflora and C. tschonoskii the species of Q. cariabilis and Q. serrata the species of C. pisifera, P. densiflora and Q. aliana in sequence grows in more fertile soil. 2. As the result of the analysis of the T. nucifera community showed, reproduction did not increase, and the characteristic of growth was not affected. The result is shown in the growth curve that was damaged by the climate and the human interference. 3. The A. palmatum was found to be as minor species in the middle layer and the crown areas did not have sufficient crown. 4. The result of the analysis of the relationship between Q. variabilis community and Q. variabilis - S. purpurascens community showed a decreasing tendency in the growth and number of species. 5. D. macropodum which constituted the dominance species in the middle layer had a nomal growth curve, and then the successional trend of D. macropodum species seems to be located in the climax species.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.347-351
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• 2012

본 연구는 기후변화로 인한 국내 낙동강 유역의 기온, 강수, 상대습도의 변동 경향을 파악하고자, 낙동강 본류의 상, 중, 하류 지역을 연구대상 지역으로 선정하여 분석을 실시하였다. 이를 위하여 기상요소인 평균, 최저, 최고 기온과 상대습도 및 강우 자료를 기상청의 관측 자료를 활용하여 수집하였다. 분석을 실시함에 있어서 연평균, 최고, 최저 기온과 연평균, 최고, 최저 상대습도를 분석하였으며, 강우량 관측 자료를 통해 총 강우량, 강우집중률, 일 최대강우량을 고려하였다. 분석방법은 기후변화로 인한 기상자료의 변동 경향을 파악하기 위하여 비모수적 경향성 검정인 Mann-Kendall Test, Hotelling-Pabst Test, Sen's Test 3가지의 검정방법을 사용하였으며, 표준정규변량의 크기를 통하여 변동 경향의 유의성을 비교해보았다. 또한, 각 요소별 관측 자료의 상위 10개, 하위 10개의 자료를 통하여 최근(1995~2011)과 과거(1973~1994)의 기상요소들을 비교하여 변동 특성을 파악하였다. 연구지역 중 낙동강 중류 지점에 위치하는 구미의 경우, 요소별 자료 중 연평균기온의 상위 9개의 자료가 최근 17년 이내에 포함되어 있으며, 연 최저 및 최고 기온의 6개의 자료가 포함되어 있어 기후온난화가 진행되고 있음을 확인하였다. 연 최저 상대습도의 경우 3가지 경향성 검정 방법을 통하여 과거자료에 비해 하강하는 추세를 보이고 있다. 강우자료 분석 결과 관측이 시작된 이래 연강수량 중 상위 10개의 자료에서 7개가 최근에 발생한 것으로 분석되었고, 일 최대강우량은 9개가 포함되어 있다. 위의 요소별 분석 결과 낙동강 유역의 연강수량 및 강우강도는 대체적으로 증가하고, 기온 또한 증가하는 등 기후 변화로 인한 지구온난화현상이 국내에서도 나타나는 것을 확인 할 수 있었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.197-197
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• 2016

Forecasting future drought events in a region plays a major role in water management and risk assessment of drought occurrences. The creeping characteristics of drought make it possible to mitigate drought's effects with accurate forecasting models. Drought forecasts are inevitably plagued by uncertainties, making it necessary to derive forecasts in a probabilistic framework. In this study, a new probabilistic scheme is proposed to forecast droughts, in which a discrete-time finite state-space hidden Markov model (HMM) is used aggregated with the Representative Concentration Pathway 8.5 (RCP) precipitation projection (HMM-RCP). The 3-month standardized precipitation index (SPI) is employed to assess the drought severity over the selected five stations in South Kore. A reversible jump Markov chain Monte Carlo algorithm is used for inference on the model parameters which includes several hidden states and the state specific parameters. We perform an RCP precipitation projection transformed SPI (RCP-SPI) weight-corrected post-processing for the HMM-based drought forecasting to derive a probabilistic forecast that considers uncertainties. Results showed that the HMM-RCP forecast mean values, as measured by forecasting skill scores, are much more accurate than those from conventional models and a climatology reference model at various lead times over the study sites. In addition, the probabilistic forecast verification technique, which includes the ranked probability skill score and the relative operating characteristic, is performed on the proposed model to check the performance. It is found that the HMM-RCP provides a probabilistic forecast with satisfactory evaluation for different drought severity categories, even with a long lead time. The overall results indicate that the proposed HMM-RCP shows a powerful skill for probabilistic drought forecasting.

• 한국방재학회 논문집
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• 제11권3호
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• pp.175-182
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• 2011

재해의 위험으로부터 안전을 추구하는 시민들의 욕구는 계속 증가하고 있으며 이와 관련하여 최근 안전도시 만들기 등이 이슈가 되고 있다. 기후 및 기상특성이 상이한 세계 도시들을 대상으로 안전도시로서 평가를 받으려면 각 도시가 처한 재해위험성을 평가하는 과정이 필요하다. 본 연구에서는 이와 관련하여 세계 주요도시의 실제 관측 강우량을 수집하였다. 서로 다른 특성을 가지는 강우를 비교하기 위해 특정 지역에서 최대로 발생가능할 것으로 예상되는 가능최대강수량을 이용하여 빈도계수 등 여러 가지 지표를 계산해보았다. 이러한 지표를 이용한 결과 우리나라 주요 도시가 보여주는 강우특성을 고찰할 수 있었다. 우리나라 호우의 강수량은 변동성이 다른 세계 주요 도시와 비교할 때 상대적으로 큰 특성을 가지고 있었다. 이러한 비교 결과들은 세계도시를 대상으로 하는 수해위험도 평가방법의 개발뿐만 아니라 향후 수해방지대책의 방향설정에 유용하게 사용될 수 있을 것으로 판단된다.

• 대기
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• 제28권4호
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• pp.415-425
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• 2018

The roles of atmospheric heating formation and distribution on the global circulation are of utmost importance, and those are directly related to not only spatial but also temporal characteristics of monsoon system. In this study, before we clarify the characteristics of apparent heat source <$Q_1$> and moisture sink <$Q_2$>, comparisons of three reanalysis datasets (NCEP2, ERA-Interim, and JRA-55) in its global or regional patterns are performed to clearly evaluate differences among datasets. Considering inter-hemispheric difference of global monsoon regions, seasonal means of June-July-August and December-January-February, which is summer (winter) and winter (summer) in the Northern (Southern) Hemisphere are employed respectively. Here we show the characteristics of eight different regional monsoon regions and find contributions of <$Q_2$> to <$Q_1$> for the regional monsoon regions. Each term in apparent heat source and moisture sink is shown to come from the ERA-Interim dataset, since the ERA-Interim could be representative of three datasets. The NCEP2 data has a different characteristic in the ratio of <$Q_2$> and <$Q_1$> because it overestimates <$Q_1$> compared to the other two different datasets. The Australia monsoon has been performing better over time, while some regional monsoons (South America, North America, and North Africa) have been showing increasing data inconsistency. In addition, the three reanalysis datasets are getting different marching with time, in particular since the early 2000s over South America, North America, and North Africa monsoon regions. The recent inconsistency among the three datasets that may be associated with the global warming hiatus remains unexplored.

• 대한원격탐사학회지
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• 제37권1호
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• pp.85-95
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• 2021

Recently, as data mining and artificial neural network techniques are developed, analyzing large amounts of data is proposed to reduce the dimension of the data. In general, empirical orthogonal function (EOF) used to reduce the dimension in the ocean data and recently, Self-organizing maps (SOM) algorithm have been investigated to apply to the ocean field. In this study, both algorithms used the monthly Sea level anomaly (SLA) data from 1993 to 2018 around the East Asia Coasts. There was dominated by the influence of the Kuroshio Extension and eddy kinetic energy. It was able to find the maximum amount of variance of EOF modes. SOM algorithm summarized the characteristic of spatial distributions and periods in EOF mode 1 and 2. It was useful to find the change of SLA variable through the movement of nodes. Node 1 and 5 appeared in the early 2000s and the early 2010s when the sea level was high. On the other hand, node 2 and 6 appeared in the late 1990s and the late 2000s, when the sea level was relatively low. Therefore, it is considered that the application of the SOM algorithm around the East Asia Coasts is well distinguished. In addition, SOM results processed by SLA data, it is able to apply the other climate data to explain more clearly SLA variation mechanisms.

• 한국동물생명공학회지
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• 제37권4호
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• pp.298-302
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• 2022

South Korea has a temperate climate with four distinct seasons. However, summers are extremely hot and humid, which negatively affects industrial animal production. Hanwoo are native cattle that have traditionally been raised in the natural environment of Korea. The present study investigated the effects of birth and lactation season on the birth and weaning weights of Hanwoo calves. Data were collected from 100 local breeding farms between 2016 and 2021. A total of 56,970 (males, 29,530; females, 27,440) Hanwoo calves were classified according to sex or birth and weaning season (March-May, spring; June-August, summer; September-November, fall; and December-February, winter). The birth weight of Hanwoo calves differed according to the birth season. As such, birth weight of the summer-born calves was the lowest. Additionally, the 90-day weaning weight was positively correlated with birth weight. Interestingly, however, the 90-day weaning weight was not related to the birth season but was related to the 2-month seasonal effect during the lactation period. Furthermore, the 90-day weaning weight was the lowest during the summer lactation period. In the beef cattle industry, daily weight gain is an important economic characteristic related to feed efficiency and growth. Our findings will contribute the management of Hanwoo cattle and analysis of changes in economic characteristics due to high temperatures.

• 농업과학연구
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• 제49권2호
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• pp.215-226
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• 2022

This study aims to investigate the soil environment characteristics of the Abies koreana community, which is currently showing a continuous decline in its size, in order to provide fundamental data for the management and creation of a conservation plan for the Abies koreana communities at the Korean national parks of Sobaeksan, Deogyusan, and Jirisan. Soil depth investigations were conducted at depths deeper than 40 cm into the B horizon at most study sites, except for the Dwaejipyeongjeon and Byeoksoryeong sites. The soil water content exceeded 30% on average, and these soils showed low bulk density levels. The soil texture was found to be the loamy or silty loam type at most study sites. It was also found in a chemical characteristic assessment that the soil samples contained more than 10% organic matter at most study sites. The cation exchange capacity (C.E.C.) and total N concentration levels were also high at most study sites. However, the soil showed low exchangeable K⁺, Na⁺, Ca²⁺, and Mg²⁺ levels at most study sites. Finally, the pH values were 4.90, 4.53, and 4.60 at soil depths of 10 cm at the Sobaeksan, Deogyusan and Jirisan sites, respectively, outcomes that are notably lower than the average levels in soil from Korean forests according to the literature. This appears to be due to the cold and wet climate of these subalpine regions given the reduced leaf-litter decomposition rate and accumulation of organic acids.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.124-124
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• 2022

Wheat (Triticum aestivum L.) is the major staple foods and is in increasing demand in the world. The elevated temperature due to changes in climate and environmental conditions is a major factor affecting wheat development and grain quality. The optimal temperature range for winter wheat is between 15~25℃, it is necessary to study the physiological characteristic of wheat according to the elevated temperature. This study presents the effect of elevated temperature on the yield and quality of two Korean bread wheat (Baekkang and Jokyoung) in a temperature gradient tunnel (TGT). Two bread wheat cultivars were grown in TGT at four different temperature conditions, i.e. TO control (near ambient temperature), T1 control+1℃, T2 control+2℃, T3 control+3℃. The period from sowing to heading stage has accelerated, while the growth properties including culm length, spike length and number of spike, have not changed by elevated temperature. On the contrary, the number of grains per spike and grain yield was reduced under T3 condition compared with that of control condition. In addition, the. The grain filling rate and grain maturity also accelerated by elevated temperature (T3). The elevating temperature has led to increasing protein and gluten contents, whereas causing reduction of total starch contents. These results are consistent with reduced expression of starch synthesis genes and increased gliadin synthesis or gluten metabolism genes during late grain filling period. Taken together, our results suggest that the elevated temperature (T3) leads to reduction in grain yield regulating number of grains/spike, whereas increasing the gluten content by regulating the expression of starch and gliadin-related genes or gluten metabolism process genes expression. Our results should be provide a useful physiological information for the heat stress response of wheat.