• 한국태양에너지학회 논문집
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• 제31권3호
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• pp.133-144
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• 2011

The objective of this study is to analyze the characteristic of radiation environment in the urban and rural through the field observation in the summer. The radiation balance was compared through the measurement of the shortwave radiation and long-wave radiation in the urban, sub-urban, and rural. The following conclusion could be obtained from this research. (1)In the results of observation including the rain-day, it was found that the short wave radiance in the urban is lower about 10% than the rural. (2)The upper part of atmosphere layers in the urban are aabsorb much short wave radiation energies compared with the rural relatively. It can increase the temperature of the upper part of atmosphere layers and the emittance of long wave radiation. (3)The ratio of the downward short wave radiation to the downward long wave radiation was 1.24 for the urban, 1.28 for sub-urban and 1.35 for rural. It can be estimated that the atmosphere condition of the rural is better than that of other areas. (4)The net radiation of the rural was lower that of the urban. It was found that the energy in and outflow of the rural is easier than that of the urban. (5)The temperature variation for the long-wave radiation change of the rural showed more sensitive than that of the urban. It was came from the radiation characteristics of the surrounding environment and can be used as the important index to evaluate the thermal environment characteristic of urban.

• 한국재난정보학회 논문집
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• 제13권4호
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• pp.413-421
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• 2017

본 연구에서는 전국 실제 이재민 임시주거시설 지정 현황에 대한 면밀한 조사와 분석을 통하여 농촌지역과 도시지역의 이재민 임시주거시설의 격차를 해소하고자, 전국의 이재민 임시주거시설의 현황을 파악하였다. 분석결과, 도시지역의 지정된 이재민 임시주거시설이 농촌지역보다 시설면적이 크고 수용능력이 높은 시설 위주임을 추정 할 수 있으므로 농촌지역 역시 많은 인원을 수용할 수 있는 능력을 갖춘 새로운 시설 지정이 필요하다고 판단된다. 또한 농촌지역 대표지역 이재민 임시주거시설 분석결과 지자체마다 이재민 임시주거시설 종류가 상이하게 지정 되었으며, 개소수 역시 지자체별 편차가 크게 나타났다. 이에 지자체에서 이재민 임시주거시설을 지정하는 절차와 체계의 개선이 필요할 것으로 판단된다.

• 한국농공학회논문집
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• 제61권5호
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• pp.101-108
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• 2019

The domestic duck industry is the sixth-largest among the livestock industries. However, 34.3% of duck houses were the duck houses arbitrarily converted from plastic greenhouses. This type of duck house was difficult to properly manage internal air temperature and humidity environment. Humidity environment inside duck houses is an important factor that directly affects the productivity and disease occurrence of the duck. Although the humidity environments of litters (bedding materials) affect directly the inside environment of duck houses, there are only few studies related to humidity environment of litters. In this study, evaporation rates from litters were evaluated according to air temperature, relative humidity, water contents of litters, and wind speed. The experimental chamber was made to measure evaporation rates from litters. Temperature and humidity controlled chamber was utilized during the conduct of the laboratory experiments. Using the measured data, a multi linear regression analysis was carried out to derive the calculation formula of evaporation rates from litters. In order to improve the accuracy of the multi linear regression model, the partial vapor pressure directly related to evaporation was also considered. Variance inflation factors of air temperature, relative humidity, partial vapor pressure, water contents of litters, and wind speed were calculated to identify multicollinearity problem. The Multiple $R^2$ and adjusted-$R^2$ of regression model were calculated at 0.76 and 0.71, respectively. Therefore, the regression models were developed in this study can be used to estimate evaporation rates from the litter of duck houses.

• The Plant Pathology Journal
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• 제36권4호
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• pp.305-313
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• 2020

Host shifting and host expansion of fungal plant pathogens increases the rate of emergence of new pathogens and the incidence of disease in various crops, which threaten global food security. Magnaporthe species cause serious disease in rice, namely rice blast disease, as well as in many alternative hosts, including wheat, barley, and millet. A severe outbreak of wheat blast due to Magnaporthe oryzae occurred recently in Bangladesh, after the fungus was introduced from South America, causing great loss of yield. This outbreak of wheat blast is of growing concern, because it might spread to adjacent wheat-producing areas. Therefore, it is important to understand the host range and population structure of M. oryzae and related species for determining the evolutionary relationships among Magnaporthe species and for managing blast disease in the field. Here, we collected isolates of M. oryzae and related species from various Poaceae species, including crops and weeds surrounding rice fields, in Korea and determined their phylogenetic relationships and host species specificity. Internal transcribed spacer-mediated phylogenetic analysis revealed that M. oryzae and related species are classified into four groups primarily including isolates from rice, crabgrass, millet and tall fescue. Based on pathogenicity assays, M. oryzae and related species can infect different Poaceae hosts and move among hosts, suggesting the potential for host shifting and host expansion in nature. These results provide important information on the diversification of M. oryzae and related species with a broad range of Poaceae as hosts in crop fields.

• 한국환경농학회지
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• 제37권3호
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• pp.160-165
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• 2018

BACKGROUND: Mixed cropping of legume and grass was effective system in view point of providing organic matter and nitrogen or reducing the nitrogen starvation of following crop. The relation of the change of N and P constituents depending on the cropping types and those effects on the growth and nutrient uptake of the following crop were observed. METHODS AND RESULTS: Three cropping types, hairy vetch mono cropping, barley mono cropping, and mixed cropping of hairy vetch and barley were applied. Soil properties, growth characteristics, and nitrogen production of green manure crops were observed. In additions, the effect of cropping types on the growth pattern of corn as the following crop was observed. In the mixed cropping system, creeping type hairy vetch climbed to the erect type barely for light utilization resulting in improvement of light interception rate and higher LAI (Leaf Area Index) than in mono cropping. Mixed cropping showed higher biomass production and soil nitrogen availability among the cropping types, indicating relatively much more nutrient supply and higher yield production of following crop. CONCLUSION: Mixed cropping showed relatively higher LAI (dry matter) mainly because of intense competition for light utilization usually after flowering stage. Mixed cropping also showed relatively higher yield of corn, the following crop rather than other types, mainly due to the more biomass production potential and higher N and P production ability. Therefore, mixed cropping was adaptable method to reduce or replace chemical fertilizer application for environmentally-friendly agriculture.

• 한국농촌건축학회논문집
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• 제15권4호
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• pp.17-24
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• 2013

Rural community in Korea being changed to aging community, declining population and income loss by the industrialization and the urbanization. The weak class in rural is confronted with more poorly environment. So it is needed to check the quality of the weak class's house in rural. Basically proposes of this paper is to find ways about rural housing improving and the vitality of rural community. This paper contents rural housing problems through the paper review and house repair characteristics for the weak class. Data for statics analysis were obtained from house repair support program for the weak class in Jeonnam province from 2011 to 2012. The results of this paper are as follow: First, house repair items ranking for the weak class in rural was insulation & heating, toilet, structure, indoor environment, electricity, outside and kitchen & waterproof. This result was reflected that weak class's energy bills is high ratio compared with income. Second, health facilities were improved for the socially disadvantaged's convenience in considering that most of weak class is a senior. Last, most of houses for weak class in rural are old clay wall and block wall. So these houses are reinforced the wall for structural safety.

• 한국농촌건축학회논문집
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• 제14권1호
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• pp.67-74
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• 2012

As the rural economy is worsening day by day due to rapidly declined population and increase of aging generation, the emptiness in the rural areas are becoming increasingly intensifying. In particular, urban runoff of young adults and middle-aged people and the decrease in birth rate have shrunk the rural population reaching to raise concerns on the stage of emptiness. On the other hand, people in the urban areas with rapid industrialization and overcrowding call for the variety of housing needs moving away from monolithic housing types. In order to solve problems of rural communities such as emptied out rural society as well as the problems of urban communities in overcrowdings, environment, and housing, it is required to develop an urban-countryside village complex pursuing advantages of the rural environment and convenience of urban living. Of this time, there needs a change in rural development policies which can make the urban residents migrate and settle in the rural areas as they are naturally embracing the rural life according to the social background and demand.

• 식물병연구
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• 제22권3호
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• pp.190-193
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• 2016

In 2010 and 2012, damping-off symptoms were found on melon seedlings grown in Yeongam and Suncheon, Korea. Water-soaked and discolored lesions appeared on the lower stems of the infected plants. The diseased plants became wilted and stunted, and eventually collapsed. On the basis of morphological characteristics and molecular analyses of internal transcribed spacer (ITS) rDNA and cytochrome oxidase II (cox2) sequences, the causal organism was identified as Pythium spinosum. The isolates were pathogenic to melon under pot conditions. To our knowledge, this is the first report of P. spinosum causing damping-off on melon in Korea.

• Mycobiology
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• 제43권3호
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• pp.343-346
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• 2015

In 2006~2010, leaf spot symptoms, that is, small, yellow spots that turned into dark brown-to-black lesions surrounded by a yellow halo, were observed on Cymbidium spp. in Gongju, Taean, and Gapyeong in Korea. A Fusarium species was continuously isolated from symptomatic leaves; in pathogenicity testing, isolates caused leaf spot symptoms consisting of sunken, dark brown lesions similar to the original ones. The causal pathogen was identified as Fusarium subglutinans based on morphological and translation elongation factor 1-alpha sequence analyses. This is the first report of F. subglutinans as the cause of leaf spot disease in Cymbidium spp. in Korea.

• 한국농공학회논문집
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• 제60권2호
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• pp.75-84
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• 2018

Thermal stress of livestock has been issued due to recent climate change trends and this causes reproductive disorders, decreased feed consumption, immunosuppression, and increased mortality of animals. Concept of THI has been widely used to quantitatively evaluate the degree of thermal stress for animals, however use of this concept is restricted for animals living in the enclosed facilities such as mechanically ventilated broiler houses. In this study, time-based internal energy flow and variation trends of temperature and humidity were analyzed based on BES technique. Local weather data, insulation characteristics of building materials, heat and moisture generation rate from broilers according to age, algorithm of ventilation operation were adopted for boundary condition of the model to accurately compute THI values inside the mechanically ventilated broiler house. From the BES computation, excess frequency of THI threshold in Jeju city was highest on the assumption that air conditioning equipments were not installed. When general raising density ($39kg\;m^{-2}$) was adopted, total 2,191 hours were exceeded. Excess hours of THI threshold were strongly related to the cumulative air temperature ($R^2=0.87$).