• 식물병연구
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• 제8권1호
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• pp.1-10
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• 2002

2001년 기상의 특징은 3월부터 5월까지 계속된 극심한 가뭄과 생육기간 내내 계속된 고온현상 그리고 별다른 태풍의 내습 없이 9, 10월 수확기 맑은날의 지속으로 요약할 수 있다. 벼는 순조로운 기상 때문에 잎, 이삭도열병, 세균성벼알마름병, 흰잎마름병, 잎집무늬마름병의 발생이 예년에 비해 경미하였으나, 감비추진 정책에 의해 생육후기 깨씨무늬병이 발생하여 전국적으로 문제시되었으며 그동안 발생이 적었던 줄무늬잎마름병이 경기, 충청, 호남 서해안지역을 중심으로 많이 발생하였다. 고추는 생육기 비가 많이 왔던 전남북 지역에서 역병 발생이 심하였으며 토마토와 오이는 대부분 예년에 비해 병발생이 적었다. 수박의 경우는 꽃자리 부분이 썩는 푸른곰팡이병이 전국적으로 발생하였으며 CGMMV는 전년에 비해 상당폭 발생면적이 감소하였고 노지재배의 경우 탄저병 발생이 예년에 비해 심하였다. 참외와 딸기도 전년에 비하여 병발생이 경미하였으며 예년에 발생이 많았던 참외의 급성위조증상도 발생이 대폭 감소하였다. 마늘·양파의 흑색썩음균핵병은 봄철의 가뭄과 고온현상으로 병발생의 전년의 절반수준으로 감소하였다. 감자의 풋마름병은 발병포장이 증가하는 경향이었으며 고구마의 덩굴쪼김병도 발생이 감소하였다. 사과의 경우 전반적으로 병 발생이 예년에 비해 경미하였으며 배는 흰가루병이 많이 발생하였다. 맥류의 붉은곰팡이병은 예년처럼 거기 발생이 없었다.

• 한국ITS학회 논문지
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• 제9권4호
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• pp.68-79
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• 2010

기상조건은 도로 및 운전조건을 열악하게 함으로써 교통사고와 정체의 원인이 되며, 운전자의 통행선택에 영향을 미쳐 기종점통행특성도 변화시킨다. 기종점 통행량은 교통계획에 있어 필수적으로 요구되는 자료이지만, 기상조건과 통행량과의 관련성을 검토한 연구는 거의 없는 실정이다. 본 연구는 강설조건이 기종점간 통행특성에 미치는 영향을 분석한 연구로, 1998년-2008년 기상자료와 TCS 통행량 자료를 이용하여 강설일과 비강설일의 차종별 일통행량, 평균통행거리를 비교 분석하였으며, 강설수준별 통행량 관계를 제시하였다. 분석결과 강설일 대비 비강설일의 통행량은 감소하며, 통행거리도 감소한다는 것을 확인하였으며. 강설시 주말/평일별 차종별로 통행특성의 차이가 있고, 강설수준에 따른 통행량의 차이도 있으나 그 정도는 크지 않다는 것을 제시하였다.

• 식물병연구
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• 제24권1호
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• pp.52-58
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• 2018

배를 유기재배하는 과원에서 문제가 되는 주요 병을 효과적으로 방제할 수 있는 친환경유기농자재 살포프로그램을 도출하기 위하여 친환경유기농자재 살포에 따른 검은별무늬병과 붉은별무늬병에 대한 방제효과를 관행재배와 비교 검정하였다. 석회유황합제와 석회보르도액을 10회 살포한 친환경방제구에서는 관행재배과원에 비해서 잎에 발생하는 검은별무늬병과 붉은별무늬병에 대해 40% 이상의 방제효과를 증대시켰다. 석회유황합제만을 기상조건을 고려하여 강우 전후에 8회 살포한 친환경방제구에서도 관행재배과원에 비해서 과실에 발생하는 검은별무늬병에 대해 30% 이상의 방제효과를 증대시켰다. 배 유기재배시 기상조건을 고려하여 친환경유기농자재 살포시기를 조절하는 친환경방제로 주요 병의 효율적 관리가 가능하리라 전망된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.539-541
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• 2009

A severely cold weather condition of King Sejong Station, Antarctica becomes a very severe condition for an installation/operation of wind generation system. When the existing wind generation system works, it may cause a damage and destruction of wind generation system and can bring about big problems in terms of the power quality. Accordingly, it is essential to obtain technologies for the installation and operation of small wind generation system for the polar region's wind generation, and to assess and demonstrate the performance in the severely-cold environment and the polar wind generation system's development, supplementation, alteration. Also, as the available power of King Sejong Station, Antarctica, the diesel generator has been mainly used, and the wind generator has been used in the hybrid form. Wind generation and diesel generation has the different load following control each other. In the wind generation, the generated power very rapidly changes according to the change of the velocity of the wind. On the other hand, the diesel generation shows very gentle change in the velocity of output. Therefore, the study is intended to analyze the 10kw small wind generator-diesel generator's power quality of King Sejong Station, Antarctica, which is the hybrid system installation area.

• The Plant Pathology Journal
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• 제34권2호
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• pp.93-103
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• 2018

Leaf blotch of wheat caused by Bipolaris sorokiniana is a major constraint to wheat production, causing significant yield reduction resulting in severe economic impact. The present study characterizes to determine and compare pathogenic variability exist/not based on components of leaf blotch disease development and level of aggressiveness due to agroclimatic condition of B. sorokiniana in wheat. A total of 169 virulent isolates of B. sorokiniana isolated from spot blotch infected leaf from different wheat growing agroclimate of Bangladesh. Pathogenic variability was investigated on a susceptible wheat variety 'kanchan' now in Bangladesh. A clear evidence of positive relationship among the components was recorded. From hierarchical cluster analysis five groups were originating among the isolates. It resolved that a large amount of pathogenic diversity exists in Bipolaris sorokiniana. Variation in aggressiveness was found among the isolates from different wheat growing areas. Most virulent isolates BS 24 and BS 33 belonging to High Ganges River Flood Plain agro-climatic zones considered by rice-wheat cropping pattern, hot and humid weather, high land and low organic matter content in soil. Positive relationship was found between pathogenic variability and aggressiveness with agro-climatic condition.

• Journal of Ginseng Research
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• 제4권2호
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• pp.197-221
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• 1980

Habitat observation, cultural experience of old and present plantation, weather factors in relation to crop stand and water physiology of root and leaf were reviewed. According to habitat observation ginseng plants love water but plate wit talus well grow at drained place with high moisture content in air and soil while ginseng plants were not found in dry or wet place. According to cultivation experience ginseng plants require abundant water in nursery and main field but most old planters believe that ginseng plaints are draught-loving thus require little water. The experience that rain especially in summer i.e unfavorable might be due to mechanical damage of leaves arid leaf disease infection, or severe leaf fall which is caused by high air temperature and coinsided with rain. According to crop stand observation in relation to weather factors abunsant water increased each root weight but decreased total yield indicating tile increase of missing root rate. Rain in summer was unfavorable too. Though rain in June was favorable for high yield general experience that cloudy day and rain were unfavorable might be due to low light intensity under shade. Present leading planters also do loot consider the importance of water in main field. Water content is higher in top than in root and highest in central portion of root and in stem of top. For seedling the heavier the weight of root is tile higher the water content while it reveries from two years old. Water potential of intact root appeared to be -2.89 bar suggesting high sensitivity to water environment. Under water stress water content severly decreased only in leaf. Water content of leaf appeared to be 78% for optimum, below 72% for functional damage and 68% for perm anent wilting. Transpiration or curs Principally through stomata in lower side of leaf thus contribution of upper side transpiration decreased with the increase of intensity. Transpiration is greater in the leaves grown under high light intensity. Thus water content is lower with high light inte nsity under field condition indicating that light is probable cause of water stress in field. Transpiration reached maximum at 10K1ut The decrease of transpiration at higher temperature seems to be due to the decrease of stomata aperture caused by water stress. Severe decrease of photosynthesis under water stress seems to be principally due to functional damage which is not caused by high temperature and Partly due to poor CO2 supply. Water potential of leaf appeared to be -16.8 bar suggesting weakness in draught tolerance. Ginseng leaves absorb water under high humidity. Water free space of leaf disc is %mailer than that of soybean leaf and water uptake appears to be more than two steps.

• 한국철도학회논문집
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• 제20권1호
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• pp.99-110
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• 2017

유라시아 이니셔티브의 일환으로 남북철도 연결사업을 실시하고 이를 통한 철도 물류망을 확보할 경우 대한민국은 또다른 경쟁력을 확보하고 이를 바탕으로 한 성장의 한 기틀이 마련될 수 있을 것이다. 남북철도 연결사업에서 철도노반분야의 가장 중요한 부분은 북한철도의 개량 또는 건설이다. 북한의 경우 지질학적으로는 대한민국과 큰 차이를 보이고 있지 않으나 특히 동절기 기후는 큰 차이를 보이고 있다. 동절기 기후에서 가장 철도 운행 안전에 피해를 주는 것은 동상이다. 동상은 선로구조물의 융기를 유발하여 철도차량의 운행안정성에 큰 위험요소로 작용한다. 하지만 대한민국은 북한에 비하여 상대적으로 온화한 기후로 인하여 극한의 조건에 대한 연구가 부족하며, 철도설계기준에도 구체적인 방안이 없는 실정이다. 따라서 본 연구에서는 극한조건에서의 철도지하횡단구조물의 동상에 대하여 연구하였으며, 국외기준 분석 및 현장시공을 통한 철도설계기준 개정방안에 대하여 분석하였다.

• Korean Journal of Geomatics
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• 제3권1호
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• pp.33-41
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• 2003

Every year, several typhoons hit the Korean peninsula and cause severe damage. For the prevention and accurate estimation of these damages, real time or almost real time flood information is essential. Because of weather conditions, images taken by optic sensors or LIDAR are sometimes not appropriate for an accurate estimation of water areas during typhoon. In this case SAR (Synthetic Aperture Radar) images which are independent of weather condition can be useful for the estimation of flood areas. To get detailed information about floods from satellite imagery, accurate classification of water areas is the most important step. A commonly- and widely-used classification methods is the ML(Maximum Likelihood) method which assumes that the distribution of brightness values of the images follows a Gaussian distribution. The distribution of brightness values of the SAR image, however, usually does not follow a Gaussian distribution. For this reason, in this study the ANN (Artificial Neural Networks) method independent of the statistical characteristics of images is applied to the SAR imagery. RADARS A TSAR images are primarily used for extraction of water areas, and DEM (Digital Elevation Model) is used as supplementary data to evaluate the ground undulation effect. Water areas are also extracted from KOMPSAT image achieved by optic sensors for comparison purpose. Both ANN and ML methods are applied to flat and mountainous areas to extract water areas. The estimated areas from satellite imagery are compared with those of manually extracted results. As a result, the ANN classifier performs better than the ML method when only the SAR image was used as input data, except for mountainous areas. When DEM was used as supplementary data for classification of SAR images, there was a 5.64% accuracy improvement for mountainous area, and a similar result of 0.24% accuracy improvement for flat areas using artificial neural networks.

• KIEAE Journal
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• 제4권3호
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• pp.203-210
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• 2004

This dissertation identifies and investigates the possible control modes of hybrid ventilation system in applying to general apartments. It evaluates range of hybrid ventilation control modes in terms of indoor air quality, thermal comfort, and energy consumption in a living room and a kitchen of the $1000m^2$ apartment. The TRNSYS simulation program was used for evaluating the following four ventilation types : A ventilation mode relying on only infiltration for supplying air, A natural ventilation mode considering with weather condition, A hybrid ventilation (natural + mechanical ventilation) mode allowing minimum ventilation with no heat exchange, and a hybrid ventilation mode with heat exchange. This study shows the following results. As temperature being controlled by heating cooling equipments, there is without significant difference in thermal performance among ventilation types. Regarding Indoor Air quality, Indoor air contamination level of the hybrid ventilation case consistently keep the lower levels. The hybrid ventilation modes consume more energy by a 49% as compared to the A ventilation mode relying on only infiltration for supplying air. It is caused by the continuous ventilation for keeping good indoor air quality; the increase of energy consumption can be attributable to the increase of the heating energy. Therefore, the heat exchange between indoor and outdoor air is required during heating season in severe weather conditions. During the cooling seasons, Introducing natural ventilation can achieve energy saving by 40 ~ 45%. Thus, it can be an effective strategies for energy saving. Based on these results, a hybrid ventilation system can be suggested as an effective ventilation strategy for archiving high level of indoor air quality, thermal comfort, and energy consumption.

• 수산해양기술연구
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• 제58권3호
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• pp.230-240
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• 2022

In general, a high tension on the anchor and chain is placed when a ship at anchor is subjected to heavy weather. Mariners have to pay attention to whether dragging anchor occurs to keep the safety of the ship at anchorage since it is difficult to maintain the stable motion of ship and it causes collisions with other ships nearby. In this paper, the ship motion against the external forces was shown to obtain the fundamental data about characteristic of holding power due to nature of seabed at anchor, so practical trials were carried out in rocky area and muddy area using a trial ship around coastal area of South Korea. In muddy seabed, holding power showed reasonable tension values depending on the distance from anchor position of continuing swing motions of a ship corresponding to wind force. Meanwhile in rocky seabed, tension values on the chain appeared very high occasionally regardless of the distance from the anchor position and seemed to exceed its holding power to be the breaking strain of the chain although weather was not in a severe condition. Therefore, some of the cables laid on the seabed were presumed to be caught in a crack on the rock. It is assumed that even a small amount of external force may cause the chain to break in a moment in rocky seabed. Additionally, wind and current forces had a somewhat contradictory effect on holding power of the ship between them.