• The Korean Journal of Mycology
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• v.38 no.2
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• pp.208-209
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• 2010

Downy mildew commonly occurred in six of seven locations investigated in Korea during disease survey performed in 2007 and 2008. This report provides screened results on resistance of Korean varieties of rape to downy mildew in the field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.3
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• pp.170-175
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• 2001

This study was carried out to investigate the distribution and characteristics of off-type rice plant in farmer's paddy field. The ratio of the field contaminated by off-type rice was highest in the southwestern area, followed by the southeastern area, the central area in Korea. The occurrence density of off-type rice was higher in the southern area than the central area. The short-grain red rice was the most dominant off-type rice group, followed by extremely late and sterile rice group and long-grain red rice group in Korea. The long-grain red rice group was dominant in Jeonnam and Kyongnam, and the extremely late and sterile rice group was dominant in Jeonbuk, and the short-grain red rice group in the other provinces. The culm length of most off-type rice groups growing in the farmer's paddy fields was longer than the farmer's cultivars, and the long-grain red rice group and the short-grain red rice group were especially longer. The number of spikelets per panicle of the off-type rice groups were generally greater than the farmer's cultlvars, and in particular, the extremely late and sterile rice group and the long-grain normal rice group had more spikelet per panicle. Most of the off-type rice groups were extremely sterile.

• Research in Plant Disease
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• v.7 no.1
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• pp.11-15
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• 2001

Root rot of Cucurbitaceae plants, caused by Monosporascus cannonballus, is one of the recently described diseases in Korea. The distribution and pathogenicity of M. cannonballus were examined by field and in vitro experiments. Root rot caused by M. cannonballus occurred on melon, oriental melon, watermelon and cucumber plants. In two years of disease survey, the disease occurred at 10 and 32 fields in 1997 and 1998, respectively, which were located at Kimhae, Chinju, and Namhae in Kyeongnam province, at Kwangyang in Chonnam province, at Kwangju city, and at Yeoju and Inchon in Kyeonggi province. The disease progress in a melon field at Namhae was not observed until the middle stage of plant growth, but rapidly increased at the fruit maturing stage, resulting in more than 50% yield loss. Isolation rate of M. cannonballus was 36.7% from wilted hosts. Fusarium oxysporum and Rhizoctonia solani were also frequently isolated. In vitro test, seedlings wilted after 7∼14 days of inoculation, and perithecia were formed in infected roots 21 days later. Two cucumber cultivars, Baekbong and Eunhwa, were resistant to the disease.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.43-47
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• 2011

Korea has seasonal weathers which result in the frosting of soil in winter times, and the thawing of soil in spring. These climate characteristics result in the damaging of pavements, due to the repeated freezing and thawing of road pavements during winter and spring. In order to reduce these pavement damages, anti-frost heave layers are being specially installed, however it is being applied based on foreign researches, and therefore result in the waste of national budget. With this study, a database system was constructed for effective management and monitoring of measured temperatures and function data of 2 meters below the embankment, cut slope, and the cutting-embankment boundary, which are 15 regions picked by the frost index diagram. As the study result, an effective storage and management-purpose database was established for easy data searching and downloading for the pavement design engineers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.6
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• pp.577-584
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• 1994

A field trial was carried out to select suitable crops for diverted upland from paddy field and to investigate response of several forage crops to soil properties and ground water levels of the diverted upland at Suwon area of Korea in 1992 and 1993. Experiments were conducted in sandy loam plot and comparatively clay loam plot having higher ground water level. Rye (Paldang), triticale (Shinki), italian ryegrass (Tetraflorum) were used as wintering forage crops and maize(Suwon 19), sorghum-sudangrass hybrid(Pioneer855F), pearl millet(Suwon 6), japanese millet (King) were used as summer forage crops. Growth and yield of forage crops were better and higher in sandy loam soil having low ground water level. Among wintering forage crops, triticale recorded the highest forage yield. Rye showed high forage yield in sandy loam soil and italian ryegrass hardly survived in diverted upland of Suwon area during winter. Among summer forage crops, forage yield of sorghum-sudangrass hybrid was highest. Yield of japanese millet was not affected by soil conditions in both plots. Yields of pearl millet and maize remained relatively low in both plots.

• Research in Plant Disease
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• v.13 no.3
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• pp.131-136
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• 2007

Occurrence of popcorn disease on mulberry fruits was surveyed in several locations in Korea from 2005 to 2007. The diseased fruits turned grayish white and changed to hard and black sclerotia during overwintering after falling onto the ground. Apothecia produced from overwintered sclerotia in the fields of mulberry trees were observed in early May. Two types of apothecia were produced from the sclerotia, which were cup-shaped or club-shaped. The fungus with cup-shaped apothecia was identified as Ciboria shiraiana, and that with club-shaped apothecia as Scleromitrula shiraiana. C. shiraiana occurred at the ratio of about 6 vs. 4 in the fields. Occurrence of the disease differed remarkably depending on years, locations, and varieties of mulberry trees investigated. Field survey of the disease incidence showed that Baekhahyeongsang, Dahojosaeng, Hasusang, a native variety and Sawonppong 22 were resistant to the disease, Cheongilppong, Daeseongppong, Guksang 20 and Turkey-D were moderately susceptible, and Cateneo, Moreji and Sanggwa were highly susceptible. Disease incidence in the fields mulched with nonwoven fabrics or plastic films was much lower than that in the non-mulched fields. Disease incidence in the fields mulched with rice straws was similar to that in the non-mulched fields.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.41-49
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• 2018

This study is to analyze and evaluate water resource development potential in North Korea. The study was conducted to analyze selected potential hydropower as an indicator to evaluate water resource development potential. Potential hydropower means theoretical value about the potential capacity of river. It is used to evaluate the amount of development through the hydropower generation. For calculating potential hydropower, monthly average and annual average of rainfall for each river basin were calculated by using the data of 27 rainfall stations in North Korea. As a result of the calculation of theoretical potential hydropower by rainfall in the seven major basins in North Korea, the Aprok River basin was analyzed to be the largest with $7,562.2{\times}10^3kW$. The efficiency and utilization rate of theoretical potential hydraulic power in South Korea and North Korea was 42.3% and 36.2%, respectively. The Daedong River basin's potential hydropower utilization rate is 12.3%, which is the lowest in North Korea. In the case of Daedong River basin, more than 40% of the total population is inhabited, so demand for water and electricity is expected to be the largest. Therefore, the Daedong River basin is considered as a priority area for water resource development. The results of this study are expected to be used as basic data for future water resource development projects and research activities in North Korea.

• The Korean Journal of Community Living Science
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• v.16 no.4
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• pp.3-13
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• 2005

This study was conducted to investigate the changes in some physicochemical properties of Codonopsis lanceolata cultivated on a wild hill, which were packed with woven polypropylene (WP) or low density polyethylene (LDPE, thickness 0.04 mm) bags and stored at $4^{\circ}C$ or $20^{\circ}C$ for 30 days. Those characteristics of fresh samples were as follows. pH : 5.3, moisture and ash content $86\%$ and $5.5\%$ respectively, Ca, Mg, Na and K content Per Ins dry matter : 427.3mg, 203.4 mg, 10.2mg, 619mg, respectively and crude saponin and codonoposide : 29.7mg and 3.82mg. Among the physicochemical properties, the pH, color parameters and Ca and Mg contents decreased or changed significantly during the storage period, but the content of crude saponin and codonoposide were almost maintained as a fresh sample for 30 days except for the condition of the WP packaging and room temperature. We could conclude that both of the LDPE packaging and chilled conditions were necessary for the best storage of Codonopsis lanceolata cultured on a wild hill for a long time.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.1-12
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• 2009

Objectives: The aim of this study was to characterize the community health indicators affecting standardized mortality rate of cerebrovascular diseases(CVD) and to identify the relationship between CVD mortality and community health indicators in Gangwon-do. Methods: The community health indicators included material deprivation index, medical resource, rates of road pavement and local tax. CVD mortality and the material deprivation index were calculated in the registered death data and the 2000 census which were obtained from the Korean National Statistics Office. The community health indicators were measured using 2001 statistical year book of Ganwon-do. Data were analyzed by using Excel 2003, SAS 9.1. CVD mortality and material deprivation index were visualized by Arcview 9.1. Results: CVD mortality varied by region and sex in Gangwon-do. The highest CVD mortality in male and female were noted at Goseong-gun, the lowest CVD mortality in male was at Yangyang-gun as it of female at Pyeongchang-gun. In Taebaek city where material deprivation index was also the highest; in Pyeongchang-gun was the lowest. Also the higher material deprivation index in some regions was the higher CVD mortality was. CVD mortality was not related with community health indicators. Conclusions: The results showed the regional difference of mortality of CVD among counties and cities in Gangwon-do. It is recommended that other community health indicators besides material deprivation index, road pavement rate, medical resources and local tax affecting CVD mortality need to be considered to improve the preventive strategies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.2057-2067
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• 2013

Traffic demand forecasting for pavement management in the present can be estimated using the past trends or subjective judgement of experts instead of objective methods. Also future road plans and local development plans of a target region, for example new road constructions and detour plans cannot be considered for the estimate of future traffic demands. This study, which is the fundamental research for developing objective and accurate decision-making support system of maintenance management for the national highway, proposed the methodology to predict future traffic demands according to 4-step traffic forecasting method using EMME in order to examine significance of future traffic demands affecting pavement deterioration trends and compare existing traffic demand forecasting methods. For the case study, this study conducted the comparison of traffic demand forecasting methods targeting Daejeon Regional Construction and Management Administration. Therefore, this study figured out that the differences of traffic demands and the level of agent costs as well as user costs between existing traffic demand forecasting methods and proposed traffic demand forecasting method with considering future road plans and local development plan.