• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.126-129
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• 2007

In order to ruduce traffic-jam, it is requested to extend road. As a result, the construction of tunnels is inevitable considering our mountatinous topography. In tunnel construction work, major contamination materials occur from rock drilling, blasting rock, rock transporting, and short-creat. After rock blasting, a very high concentration of particles over $5000{\mu}g/m^3$ is maintained for 4 h when air is supplied by pans, by which the construction work has to be delayed at least 30 min. Although dry dust collectors are used, the effective operation time span is limited to 3 h. In this work, the behavior of particles in air and use of particle removal instruments are investigated. As a result, it was important to compare efficiencies of dry and hydro dust collectors.

• Journal of Life Science
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• v.9 no.6
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• pp.671-676
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• 1999

RAPD analysis using random primers were tried to evaluate the genetic variation and diversity of the nine garlic cultivars including two foreign varieties. Thirty-two primers out of 70 primers screened were used to amplify genomic DNA of garlic cultivars using polymerase chain reaction(PCR). Among a total of 151 bands amplified by 32 primers, 125 polymorphic bands were subjected to analysis for genetic relationship of garlic cultivars. The estimated size of amplified PCR products were in the range of 932 to 4,060 base pairs. Nine garlic cultivars were classified into two groups, such as group I corresponded to Changnyung and Hungary cultivars, and group II, Namdo, Sandong from China, Yecheon, Euiseong, Youngweol, Danyang, Jeongsun cultivars, with the genetic distance value of 0.271. The major ecological types of garlics, so called southern and northern types, was grouped in the genetic distance value of 0.200. The results presented in this study suggest that RAPD analysis are likely to be useful for identification of cultivars and evaluation of genetic origin in garlics.

• Journal of Plant Biology
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• v.34 no.1
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• pp.77-90
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• 1991

Fresh fungi were obtained during collection trips to Ullung Island in October, 1989, and August, 1990. Among them, some corticioid fungi were identified. Ten fungi were confirmed new to Korea and are recorded here with descriptions. They are Athelia epiphylla, Grandinia alutaria, G. gran.utosa, G. stenospora. Cylindrobasidium evolvens. Hyphoderma rlldula, H setigerum, Hypochnicium eichleri, Trechispora Illbo-ochracea, and T. farinllcea.nllcea.

• Journal of Environmental Impact Assessment
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• v.8 no.3
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• pp.61-76
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• 1999

For the effective management of urban forest, a variety of informations on urban forest needs to be accurately measured and effectively used in decision-making processes. This study aims at developing an urban forest management system with reference to GIS and making it possible to effectively manage urban forests. A detailed forest type map were constructed with the help of aerial photograph and terrestrial inventory. A geographical map in terms of slope, aspect and altitude were also prepared by Digital Elevation Model(DEM). A soil type map containing chemical characteristics were also made through soil analysis. These thematic maps which contain informations on forest type, geography and soil were digitalized with reference to GIS, and an urban forest management system of user interface were developed. With the help of this urban forest management system, various spatial and attribute informations which need for urban forest management could be easily used in decision-making processes in relation to urban forest.

• Journal of Environmental Impact Assessment
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• v.22 no.6
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• pp.609-626
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• 2013

Air quality models have been widely used to study and simulate many air quality issues. In the simulation, it is important to raise the accuracy of meteorological predicted data because the results of air quality modeling is deeply connected with meteorological fields. Therefore in this study, we analyzed the effects of meteorological fields on the air quality simulation. This study was designed to evaluate MM5 predictions by using different initial condition data and different observations utilized in the data assimilation. Among meteorological scenarios according to these input data, the results of meteorological simulation using National Centers for Environmental Prediction (Final) Operational Global Analysis data were in closer agreement with the observations and resulted in better prediction on ozone concentration. And in Seoul, observations from Regional Meteorological Office for data assimilations of MM5 were suitable to predict ozone concentration. In other areas, data assimilation using both observations from Regional Meteorological Office and Automatical Weather System provided valid method to simulate the trends of meteorological fields and ozone concentrations. However, it is necessary to vertify the accuracy of AWS data in advance because slightly overestimated wind speed used in the data assimilation with AWS data could result in underestimation of high ozone concentrations.

• Research in Plant Disease
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• v.7 no.1
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• pp.8-10
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• 2001

A stem and root rot disease of kalanchoe (Kalanchoe sp.) which is a succulent plant that provides consumers with a durable flowering pot was found in Koyang, Kyounggi province, Korea in May 1998. We found that stems and roots of potted kalanchoe had dark brown spots at the soil level. The causal organism was identified as Pjytophtora nicotianae on the basis of mycological characteristics. The fungus produced markedly papillate, ovoid to spherical sporangia, and abundant chlamydospores. Sporangia were 20∼48$\times$24∼64㎛(avg. 35.0$\times$47.3㎛) in size, and optimum temperature for the mycelial growth of the isolate was 30$\^{C}$. The fungus showed relatively different pathogenicity to 14 kalanchoe cultivars including K. blossfelana cv. Florus. cultivars florsu, calypso, Maya, and Redsing were susceptible to thedisease in root dip inoculation. This is the first report demonstrating the stem rot on kalanchoe caused by P. nicotianae in Korea.

• Research in Plant Disease
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• v.10 no.2
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• pp.142-144
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• 2004

Effect of potassium phosphonate on control of potato basal stem rot caused by Pythium myriotylum in hydroponics system was evaluated at spring and fall cultivation in Jeju island in 2001. Potassium phosphonate 200 ppm treatment, which was directly supplemented into the nutrient solution, showed 90.5%, and 100 ppm treatment showed 50.5% control value in spring cultivation. Fall cultivation, potassium phosphonate 200 ppm treatment showed 100%, and 100 ppm treatment showed 69.9% control value. Potassium phosphonate 200 ppm treatment, basal stem rot of potato started to develop 10 days ofter inoculation into the hydroponics system showed 8.0% in infection rate. Potassium phosphonate 100 ppm treatment, after 5 days showed 10.0%, and after 10 days showed 20.0% infection rate, but the non-treated was after 5 days showed 56.7%, and after 10 days showed 96.9% infection rate.

• Research in Plant Disease
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• v.12 no.3
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• pp.287-289
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• 2006

Since 2004, a gray mold on Aerides japonicum Lindenb. & Reichb. caused by Botrytis cinerea occurred in a few greenhouses at Goseong and Tongyeong, Gyeongnam, Korea. The disease mainly started on the basal part of leaves, and often lead to severe rots of whole plant. Abundant grayish mycelia and conidial mats were visible on the lesions under a humid conditions. The light gray conidia were one celled and mostly ellipsoid or ovoid in shape. The conidia were $6{\sim}21{\times}4{\sim}13{\mu}m$ in size and conidiophores were $15{\sim}34{\mu}m$ in length. The fungus formed abundant sclerotia on potato-dextrose agar after 18 days incubation at $20^{\circ}C$. The fungus was identified as Botrytis cinerea Persoon: Fries. based on its pathogenicity and mycological characteristics examined in this study. This is the first report of gray mold of Aerides japonicum caused by B. cinerea in Korea.

• Research in Plant Disease
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• v.12 no.3
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• pp.294-297
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• 2006

Leafy lettuce(Lactuca sativa L.) is one of the most important vegetable crops in Korea, cultivated throughout the year in greenhouses. During the autumn of 2005, powdery mildew of lettuce that is a new disease caused by Podosphaera fusca occurred in several plantings grown in plastic houses near Suwon in central Korea. Further survey on commercial fields of the plant in central and southern Korea revealed its widespread occurrence and severe losses. Infections occur on upper part of mature leaves often cause leaf distortions, withering, and reduced vigor and growth. Among 184 greenhouses surveyed 121 were infested by the disease and 52 showed over 10% infection rate. Yields were greatly reduced by the disease reaching only 59% compared to healthy plants. About 60% leaves of infected plant were not marketable and fresh weight of the leaves was 73.6% compared to healthy leaves. Total yield of the greenhouses infested by the disease ranged from $100{\sim}140kg$, while it was 260 kg in a non-infested greenhouse at one time harvest. Since the disease represents a threat to safe cultivation of leafy lettuce in Korea, environmentally-friend control strategies should be urgently developed.

• Research in Plant Disease
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• v.12 no.3
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• pp.235-239
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• 2006

Since the cultivation of resistance cultivar is essential for organic agriculture, Phytophthora late blight resistance of 16 advanced potato clones obtained from the potato breeding laboratory at the National Institute of Highland Agriculture was evaluated. Resistance of the clone was examined through artificial inoculation in the laboratory and in the field. Dominant isolates of the pathogen in Gangwon province produced abundant sporangia on leaves of most clones showing susceptibility. The number of sporangia ranged from $10^{7{\sim}8}sporangia/ml$ in the susceptible clones at 7 days after inoculation. However, one clone is resistant in organic farming fields. Disease incidence was 2.3% using the resistant clone. The area under disease progress curve(AUDPC) was 75.5. Contrarily, disease incidence of the susceptible variety was 100% and the AUDPC was 1773.5 during the same cultivation period. The resistance clone named as 'Haryeong' is considered suitable for organic potato cultivation in Gangwon province in Korea.