• 한국작물학회지
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• 제53권spc호
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• pp.72-77
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• 2008

This study was carried out to determine the response of the rice yield and grain quality by rice leaf folder (RLF, Cnaphalocrocis medinalis G.) and identify the damages caused by different transplanting dates, nitrogen amounts and chlorophyll amounts (SPAD value) of rice leaf. As the damage degree of RLF was getting severer, the ripened grain rate and 1000-grain weight were decreased and due to the increasing of chalky rice rate the rate of head rice was reduced. Therefore, the yield of head rice was decreased by 36% in heavily damaged rice plant. Among the physicochemical characteristics, protein content of rice grain was increased but amylose content was reduced, consequently, the palatability was deteriorated in heavily damaged rice by RLF. The degree of damage of RLF was getting serious as transplanting date was delayed and as the amount of nitrogen was increased. In the relationship between the SPAD value and the damage degree of RLF, as the SPAD value was increased by nitrogen fertilizing, the damage degree was also increased exponential functionally.

• 대한공간정보학회지
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• 제19권4호
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• pp.71-80
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• 2011

우리나라는 홍수피해를 평가하기 위한 방법으로 간편법과 개선법을 사용하다가 현재는 2004년도에 개발된 다차원 홍수피해액 산정기법을 활용하고 있다. 본 연구에서는 GIS 자료를 기초로 다차원 홍수피해액 산정기법을 이용한 댐 하류지역의 홍수피해액 평가기법을 제시하였다. 먼저 배수강제알고리듬에 기초한 횡단측선 레이어에 FLDWAV 모델을 이용한 홍수위 자료를 입력한 후 DEM 자료와의 공간연산 처리를 통해 침수심 격자를 생성하였다. 그리고, 수치지형도에서 추출한 건물 레이어와 토지피복도에서 추출한 농경지 자료를 이용하여 지자체별 건물과 농경지 자산가치를 평가하였다. 또한 건축형태별 건축단가, 도시유형별 가정용품 평가액, 농작물 단가정보, 사업체의 유형 및 재고자산 평가액 자료를 건물, 농경지, 침수심 레이어와 연계하여 항목별로 피해액을 산정하였다. 홍수피해액 분석을 통해, 200년 빈도의 홍수피해액이 100년, 50년, 10년 빈도에 비해 각각 1.19배, 1.30배 그리고 1.96배 높게 나타났다.

• 한국농공학회논문집
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• 제57권4호
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• pp.143-151
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• 2015

Recently, flood has been increased due to climate change resulting in numerous damages for humans and properties. The main objective of this study was to suggest a methodology to estimate the flood vulnerability using Potential Flood Damage (PFD) concept. To evaluate the PFD at a spatial resolutions of city/county units, the 19 representative evaluation indexing factors were carefully selected for the three categories such as damage target ($F_{DT}$), damage potential ($F_{DP}$) and prevention ability ($F_{PA}$). The three flood vulnerability indices of $F_{DT}$, $F_{DP}$ and $F_{PA}$ were applied for the 162 cities and counties in Korea for the pattern classification of potential flood damage. It is expected that the supposed PFD can be utilized as the useful flood vulnerability index for more rational and practical protection plans against flood damage.

• 농업과학연구
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• 제50권3호
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• pp.497-505
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• 2023

This study evaluated the impact of rain shelters made of plastic film on spring frost damage and fruit quality in Asian pears ('Niitaka') over two years. In 2021, during the coldest spring days (between 0:00 am and 7:00 am), temperatures dropped to -1.20 - 0.43℃ at 120 cm and -1.33 - 0.57℃ at 200 cm above ground level in the control. Conversely, the rain shelter treatment maintained higher temperatures, -0.40 - 0.87℃ at 120 cm and -0.43 - 0.77℃ at 200 cm. Flower damage was significantly lower in the rain-sheltered group, with incidences of 1.3 and 6.9% at 120 and 200 cm, respectively, compared with 18.1 and 22.6% in the control group. Visual observations verified the prevention of frost adhesion on flower organs in the sheltered group, compared with noticeable pistil death and petal browning in the control group. In 2022, when temperatures remained above 0℃, fruitlet stalk length was 5 - 6 mm longer in the sheltered group. The cumulative impact of rain shelters was evident in the improved fruit quality over the two years. This study suggests resilient cultivation strategies in the face of climate change to reduce frost damage, increase productivity, improve fruit quality, and potentially increase incomes of the farmers.

• 한국농림기상학회지
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• 제18권3호
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• pp.162-169
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• 2016

기준기상위험이란 한 지역의 평년기후조건이 작물재배에 미칠 수 있는 '농업기상학적 피해가능성'으로서, 동일 작물 재배 시 지역에 따른 재해위험을 비교하는 기준이 된다. 지구온난화로 인하여 겨울 온도는 상승할 것으로 예상되지만, 기상이변의 빈도 또한 늘어날 것으로 전망되기 때문에 미래 기후조건에서 과수의 동해, 상해 등 저온에 의한 재해위험이 주목 받고 있다. 그러나 기후의 변화는 과수 생물계절도 변화시키므로 기상조건에 근거한 단순한 재해위험 전망은 기후변화적응의 실용측면에서 별 도움이 되지 못한다. 본 연구에서는 전국 주요 지역의 과거 및 기후변화시나리오를 이용하여 배, 복숭아, 사과의 생물계절을 예측하고 생육단계별 기온과의 상호작용에 근거하여 저온 유래 기준기상위험을 계산함으로써 미래의 재해가능성을 전망하였다. 휴면해제일은 미래로 갈수록 늦어질 것으로 전망되었으며, 발아일과 개화일의 경우 빨라질 것으로 예상되었다. 대구, 전주, 목포의 경우 휴면해제일의 지연 정도가 미래로 갈수록 커졌으며 발아일과 개화일의 경우 서울, 인천 지역이 다른 지역에 비해 늦게 나타났다. 서울과 인천, 대구와 전주, 부산과 목포가 서로 비슷한 양상을 나타내었다. 휴면기 동안에는 전 지역이 동해에 안전하였으나 휴면해제-발아기 동안에는 전 지역이 동해에 취약하였고, 발아기-개화기의 위험은 미래로 갈수록 대체로 낮아졌지만 지역에 따라 위험이 커지는 곳도 있었다.

• 한국작물학회지
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• 제44권1호
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• pp.38-43
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• 1999

Over 2,000 ha of rice fields in the western and southern coastal region of Korea were flooded with sea water during the spring tide, on August 19-21, 1997, and the rice plant at heading stage was injured. The field surveys were undertaken at the sea water flooded paddy fields in Chonbuk Province, to identify the injury symptoms and rice yield damage subjected to different flooding condition and desalinization methods. Five days after sea water flooding at heading stage, the flag leaves of rice plants flooded with 30 ㎝ deep sea water withered from the tip, the withering progressed to the lower leaves in deeper flooding. The spikelets were spotted black and discolored from the tip at 50 ㎝ deep flooded rice, and some panicles changed to white at 80 ㎝ deep flooded rice. Most of the rice leaves submerged completely for an hour were withered and most of panicles changed to white. The milled rice yield, percentage of ripened grain, and 1000 grain weight of flooded rice decreased with deeper flooding water, higher water salinity and longer flooding time. Even under the same flooding conditions, the damage of rice yield varied with the growth stage: heading stage>dough stage>booting stage. Rice yield damage was less in the fields on the upper riverside than those of the fields on the estuary and seaside, because of lower water salinity. In a flooded field, the rice yield damages were reduced as the distance increased from the levees where the sea water inflowed and increased as the distance increased from the fresh water irrigation gate. The desalinization treatments consisting of frequent exchange of irrigation water and spraying with fresh water soon after flooding effectively reduced the rice yield damage.

• 농촌지도와개발
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• 제15권1호
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• pp.113-144
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• 2008

The objective of this study aims to explore the situation of damage from wild animals in Korea. Through case study on two villages in Injae, Kangwon province and Cheongyang, Chungnam province. This overview summarises the current issues and trends in wild animals damage through two case studies. We found that there are not only to get economic damage but also not to be able to sleep to protect their farm land from animal invading. We suggest to develop physical and chemical instruments not to access their plants in farmland and to increase central and local government's damage repayments.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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• pp.200-204
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• 1994

Low temperature associated damage mechanism is not well known for asphalt concrete. Many studies have related the thermal cracking of pavement in the roadway in cold region with overall shrinkage of the pavement surface under assumption of homogeneous material. This study, however, was intiated based on the assumption that thermal incompatibility of materials (heterogeneous) in asphalt concrete mixture would be the primary cause of the damages. Acoustic emission technique and microscopic obsevation were employed to evaluate damage mechanism of asphalt concrete due to low temperature. The first method showed the sufficient evidence that asphalt concrete could be damaged by lowered temperature only. The second method showed that the damage by temperature resulted in micro-cracks at the interface between asphalt matrix and aggregate particle. It was concluded that these damage mechanisms were the primary cause of major thermal cracking of asphalt pavement in cold region.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.878-885
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• 1996

The brown rice drying is effective for energy saving and cost reduction. However, deterioration after drying is one problem, because the skin damage occurs during the drying. So, the measures to preserve the quality has been investigated. One of major quality deteriorations is the oxidation of fat which is contained in the bran layer. So, milling should be carried out to remove the fat as soon as possible after brown rice drying. And the low temperature storage is also worth to be examined for prevention of oxidation. The effect of skin damage on the increase of fat oxidation was clarified. For the grain of skin damage, the increased of fatty acid vaule was remarkable after 70 days elapsed from occurrence of skin damage even in $15\;^{\circ}C$ condition. Therefore it is impossible to keep grain as brown rice form after brown rice drying. For the clean rice and excessively milled rice, the quality can be preserved even in high temperature of $30\;^{\circ}C$. Therefore the brown rice drying can b applied practically using the clean rice technique.

• 한국농공학회논문집
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• 제52권3호
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• pp.113-120
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• 2010

Reduction factor for installation damage required to calculate design strength of geogrid used in MSEW(mechanically stabilized earth wall) design is usually obtained in the field test simulating real construction condition. However, damages occurred in geogrid during backfill work are influenced by many factors such as polymer types, unit weight per area, backfill construction method and gradation of backfill material and field test considering these factors demand lots of time and costs. In this study, factors affecting installation damage are analyzed and empirical method to evaluate reduction factor for installation damage using maximum particle size in backfill material is suggested.