• 한국농공학회지
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• 제32권3호
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• pp.116-129
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• 1990

A rational management of water resources in estuary reservoirs necessiates the prediction of water quality. In this study, a multiple box model for the water quality prediction was developed as a tool for the purpose of examining an adequate way to improve and maintain the water quality. Some submodels that are suitable for simulating the mixing behavior of pollutant materials in a lake were considered in this model. The model was appiled for predicting water qualities of Haenam Esturay Reservoir. The result from this study can be summarized as follows : 1.A water quality simulation model that can predict the 10-day mean value of water qualities was developed by adding some submodels that simulate the concentrations of chlorophyll-a, BOD, T-P and T-N to the existing Multiple Box Model representing the mixing and circulating of materials by the hydarulic action. 2.As input data for the model developed, the climatic data including precipitation, solar radiation, temperature, cloudness, wind speed and relative humidity, and the water buget records including the pumping discharge and the releasing discharge by drainage gate were ollected. The hydrologic data for the inflow discharge from the watershed was obtained by simulation with the aid of USDAUL-74/SNUA watershed model. Also the water quality data were measured at streams and the reservoir. 3.As a result of calibration and verification test by using four comonents of water quality such as Chlorophyll-a, BOD, T-P and T-N, it was found that the correlation coefficeints between the observed and the simulated water qualities showed greater than 0.6, therefore the capability of the model to simulate the water quality was proved. 4.The result based on the model application showed that the water quality of the Haenam Estuary Reservoir varies seasonally with the harmonic trend, however the water quality is good in winter and get worse in summer. Also it may be concluded that the current grarde of water quality in the Heanam Esutary Reservoir is ranked as grade 4 suitable only for the agricultutal use.

• Water Engineering Research
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• 제6권3호
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• pp.131-147
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• 2005

Today, a trend that tries to return the artificial space of a river to a natural one is expanding. But in Korea, which lies in the monsoon climate zone, rivers endure flood damage every year. Moreover, climatic change from global warming causes severe variations in precipitation patterns. Until recently, river restoration practices in Korea have followed partial restoration. These restorative treatments transformed artificial structures of the stream to natural ones and introduced natural vegetation by imitating natural or semi-natural streams. Treatment transformed the riparian structure and increased the diversity of micro-topography and vegetation. Furthermore, restoration recovered species composition, increased species diversity, and inhibited the establishment of exotic species. In particular, the Suip stream, which was left to its natural process for approximately 50 years, recovered its natural features almost completely through passive restoration. An urban stream, the Yangjae, and a rural stream, the Dongmoon, were restored partially by applying ecological principles. On the contrary, technological treatment applied to recover flood damage induced species composition far from the natural vegetation and decreased species diversity. Additionally, this treatment increased exotic species. The same results were found also in benthic invertebrate and fish fauna. The above-mentioned results reflect the importance of ecological considerations in river management.

• 한국주거학회논문집
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• 제17권5호
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• pp.9-16
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• 2006

The researches on the environmental friendly buildings have carried out on the materials, environmental property, technical elements and etc., and various buildings with these green materials have built and under construction nowadays and became a new trend of the green building. And recently, new building technique which builds the wall with the soil and wood and very easy to construct (called M Earthen House) was introduced as the green building and rapidly propagated. But the research on the indoor climatic characteristics, the ability to control the environmental comfort and the influence to the human beings of these buildings are not sufficiently identified yet. In this paper, the indoor environmental characteristics and the temperature controlling ability of these buildings in summer season were measured and analysed by the Portable Indoor Air Quality Monitor(BABUC/A, LSI) measuring equipments, ana the subjective test on the thermal environment of the subjects were carried out to evaluate the thermal comfort. The results can be summarized as follows; 1) Compared to the outdoor dry bulb temp.($15.4{\sim}28.7^{\circ}C$), the indoor temp. was $19.5{\sim}26.8^{\circ}C$. It showed the temperature controlling ability of the M earthen house was outstanding. And the indoor relative humidity, compared to the outdoor($45.4{\sim}100%$), was $58.1{\sim}76.4%$, it showed the humidity controlling ability of the M earthen house was also outstanding. 2) The thermal environment was evaluated as 'comfort'(neutral-slightly warm) and the humidity was also evaluated as 'comfort'(neutral-slightly humid). So, the results of the physical and subjective evaluation on the indoor thermal comfort in summer season were 'neutral' and 'comfort' coincidently, it was confirmed that the controlling ability of the indoor temperature and humidity of the M earthen house was very excellent.

• 응용통계연구
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• 제20권1호
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• pp.1-9
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• 2007

한국의 네 개 도시(서울, 대구, 춘천, 영천)의 일일 최고기온을 모형화하여, 이에 적합한 분포를 제안하고 분포의 적합성을 여러 가지 방법에 의하여 검토하였다. 제안된 분포는 극단간 분포의 일종이며, 적합성 검토는 카이제곱 적합도 검정, Q-Q plot,확률 그림과 5000번의 모의실험을 통하여 허용한계를 구하였다 그 결과 제안된 극단간 분포(Extreme Value Distribution)가 일일 최고기온을 잘 설명하고 있음을 확인할 수 있었다. 논문에서 나타난 실제 데이터의 그림은 서울의 1월과 6월을 중심으로 하였고, 대상지역의 2006년과 100년 후 2105년의 평균기온과, 제 안된 극단값 분포에 의해 95% 신뢰구간하에서 일일 최고기온의 평균 상한값을 예측하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.263-269
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• 1996

In indian agricultural , the energy use pattern has played dominant role in influencing the level of mechanization . Besides that the agro-climatic factors as well as the size of holdings do affect the degree of mechanization . Nearly 30 percent of total cultivated area is owned by l76 percent of the small and tiny land holders each owning even less than a hectare. On the other hand, about 2 percent of land owners cultivate land. These variabilitieshave greatly influenced the ownership of power sources on Indian farms. Small farmers, employ human and animal energies with the use of hand tools and animal drawn equipments. Whereases, the use of tractors, power tillers, electric motors, etc. on small farms is on a marginal scale. There are few pockets and also extensive wheat growing regions where mechanical and electrical power sources are extensively used in production agriculture leading to about 185% of cropping intensity . In that region, the animal energy is employed for on the farm transport of fertilizers, fodders and fuel to support milch animals and other household activities . Inspite of high degree of mechanization, the harvesting of crops is done by human labour with few exceptions of harvesting wheat crops by combines in few pockets. In overall assessment of mechanization, the following conclusions are drawn : ⅰ) Farm operation which show a growing trend of mechanization are (a) tillge, (b) seedling (c) Irrigation (d) Plant protection application (e) Threshing and (f) Transport . ⅱ) Crop cultivation system in respect of wheat, maize and sorghum have been greatly mechanized. ⅲ) The least mechanized cropping systems are (a) vegetable production and (b) cultivation of sugarcane, cotton, rice and pulses. ⅳ) Annual production of tractor has touched the figure of 280.000 by 1995 and the total number has crossed 1.5million on Indian farms.

• 아시안잔디학회지
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• 제23권2호
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• pp.361-368
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• 2009

Cenangium ferruginosum 은 소나무류의 피목가지마름병의 원인균으로 알려져 있다. 한국에서 이 병은 1989년 처음 보고가 된 이래 2007년 봄 서울, 경기, 강원과 충북지역에서 대발생하였다. 병원균인 C. ferruginosum은 병원성이 약한 내생균으로 알려져 있으나 나무가 상처나 가뭄, 극심한 추위나 온난한 겨울 기후 등으로 인한 스트레스를 받게 되면 병 발생을 유발하게 된다. 본 연구에서는 기후변화에 따른 병 발생 동향을 이해하고자 국 내외 피목가지마름병 발생 현황 및 병원균의 특성을 설명하였다. 또한 경기, 충청, 경상지역의 발병한 잣나무 및 소나무의 병든 가지를 수집하여 병원균의 발달 과정을 관찰하였으며, 병원균을 분리하여 이들의 형태학적인 특성과 분자수준에서의 특성을 분석한 결과 C. ferruginosum 임을 확인할 수 있었다.

• Journal of Animal Science and Technology
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• 제63권1호
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• pp.77-90
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• 2021

This study aimed to assess the impact of abnormal climate events on the production of Italian ryegrass (IRG), such as autumn low-temperature, severe winter cold and spring droughts in the central inland, southern inland and southern coastal regions. Seasonal climatic variables, including temperature, precipitation, wind speed, relative humidity, and sunshine duration, were used to set the abnormal climate events using principal component analysis, and the abnormal climate events were distinguished from normal using Euclidean-distance cluster analysis. Furthermore, to estimate the impact caused by abnormal climate events, the dry matter yield (DMY) of IRG between abnormal and normal climate events was compared using a t-test with 5% significance level. As a result, the impact to the DMY of IRG by abnormal climate events in the central inland of Korea was significantly large in order of severe winter cold, spring drought, and autumn low-temperature. In the southern inland regions, severe winter cold was also the most serious abnormal event. These results indicate that the severe cold is critical to IRG in inland regions. Meanwhile, in the southern coastal regions, where severe cold weather is rare, the spring drought was the most serious abnormal climate event. In particular, since 2005, the frequency of spring droughts has tended to increase. In consideration of the trend and frequency of spring drought events, it is likely that drought becomes a NEW NORMAL during spring in Korea. This study was carried out to assess the impact of seasonal abnormal climate events on the DMY of IRG, and it can be helpful to make a guideline for its vulnerability.

• 대기
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• 제32권1호
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• pp.1-15
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• 2022

Recently, Japan's Meteorological Research Institute presented the d4PDF database (Database for Policy Decision-Making for Future Climate Change, d4PDF) through large-scale climate ensemble simulations to overcome uncertainty arising from variability when the general circulation model represents extreme-scale precipitation. In this study, the change of precipitation characteristics between the historical and future climate conditions in the Yongdam-dam basin was analyzed using the d4PDF data. The result shows that annual mean precipitation and seasonal mean precipitation increased by more than 10% in future climate conditions. This study also performed an analysis on the change of the return period rainfall. The annual maximum daily rainfall was extracted for each climatic condition, and the rainfall with each return period was estimated. In this process, we represent the extreme-scale rainfall corresponding to a very long return period without any statistical model and method as the d4PDF provides rainfall data during 3,000 years for historical climate conditions and during 5,400 years for future climate conditions. The rainfall with a 50-year return period under future climate conditions exceeded the rainfall with a 100-year return period under historical climate conditions. Consequently, in future climate conditions, the magnitude of rainfall increased at the same return period and, the return period decreased at the same magnitude of rainfall. In this study, by using the d4PDF data, it was possible to analyze the change in extreme magnitude of rainfall.

• Journal of Forest and Environmental Science
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• 제40권2호
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• pp.99-110
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• 2024

According to the REDD+ program, it is necessary to monitor, quantify, and report forest conditions in protected land areas. The objectives of this work were to quantify the average monthly aerial net primary productivity (ANPP_MONTH) of semi-arid Chaco Forest at Copo National Park (CNP), Santiago del Estero, Argentina, during the period 2000-2023, as well as its spatial distribution and relationship, and its use efficiency (RUE) of average monthly rainfall (AMR). The ANPP_MONTH model accounted for 90% of the seasonal variability from October to May, the average seasonal ANPP_MONTH was 145 tons of dry matter per hectare (t dm/ha), being the maximum in January with 192 t dm/ha and the minimum in May with 91 t dm/ha. The surface area covered by ANPP_MONTH exhibited a consistent positive trend from October to May (t test=15.65, p<0.01). Strong and significant direct relationships were found between ANPP_MONTH and AMRs, linear models explaining 90% and 96% of the variability, respectively. The results obtained become reference values for assessing the capacity of the forest systems to stock carbon for global warming mitigation and for monitoring and controlling their response to extreme climatic adversities. The average ANPP_MONTH reduces uncertainty when defining the thresholds to monitor and quantify ANPP and forest area, thus facilitating the detection of negative changes in land use in CNP. Such results evidence the National Parks Administration's high effectiveness for the maintenance of protected area and for the high ANPP of the FCHS of CNP in the period 2000-2023.

• 대한지리학회지
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• 제33권3호
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• pp.395-409
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• 1998

미국남부지방의 5개 도시를 연구지역으로 도시의 영향에 의한 강수특성변화를 파악하고 종관기상유형에 따른 특성을 규명하기 위하여 2 인치(50.08 mm) 이상의 일강수량을 가지는 강수일을 선택하여 3가지 강수유형(기단성 강수, 전선성 강수, 열대저기업성 강수)으로 구분하여 분석하였다. Houston, Dallas, 그리고 San Antonio에서는 기단성 강수가 발생할 때, 도시직역과 풍하측에 호우로 인한 강수량과 강수빈도의 증가가 나타나고 있으나 New Orleans와 Memphis에서는 종관적 분석을 통해서 볼 때 현저한 증가현상을 보이지 않는다. 경향면 분석겨로가는 전선성 강수와 열대저기업성강수 발생시 기단성 강수로 인한 호우보다 강한 경향성을 가지는 것을 보여주고, 호우로 인한 통강수량은 강수일수빈도보다 강한 경향성을 가진다. 잔차도 분석결과는 기단성 호우 발생시 도시지역과 풍하지역에 양의 잔차가 나타나는 것을 보여준다. 미국 남부의 5개도시에서 강수특성변화에 미치는 도시화의 영향에 대한 연구는 도시기후는 종관적으로 유사한 조건하일지라도 도시의 규모, 공간구조, 수체의 유무, 산업구조 등 다양한 특성에 따라 상이하게 반응함을 알 수 있었다.