• Journal of Korea Water Resources Association
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• v.40 no.6 s.179
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• pp.469-483
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• 2007

Nitrate and chloride are the most common contaminants in groundwater and their concentrations increase easily due to fertilizer consumption and urbanization. The number of time series data for groundwater quality at a single site was not sufficient to analyze trends on Jeju Island. Therefore rectangle grids were drawn for the whole island and single grid was determined to be $500m{\times}500m$ after considering similar stream density, homogeneous hydraulic coefficients, geologic features of volcanic rock and low topographic slopes. All data within each lattice were collected and arranged in time series order and analyzed using Sen's method. 10.6 % of the total lattices for chloride and 22.4% for nitrate showed upward trends from the early 1990's to the early 2000's. Especially, upward trends for nitrate concentration are distinct in the low mid-mountainous areas of western and southern watersheds. Many septic tanks and much domestic waste from the urbanization of the low mid-mountainous area have produced this upward trend. Additionally, the agricultural region has dramatically increased since the 1990's and this has led to an increase of fertilizer consumption and, as a result, nitrate concentration. Therefore, the target of any management plan for groundwater quality on Jeiu Island needs to be focused on careful land use decisions in the mid-mountainous areas which are near Halla Mountain.

• The Korean Journal of Mycology
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• v.40 no.4
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• pp.288-291
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• 2012

Korean oak wilt disease caused by Raffaelea quercus-mongolicae is vectored by the ambrosia beetle Platypus koryoensis. To prevent the spread of the disease, the beetle infested oak tree had been cut into logs, covered with plastic vinyl, fumigated with a pesticide, and stored for three years on the site where the tree was cut. This study was carried out to get information on the fungi colonizing the fumigated oak wood. Wood disk samples collected from the fumigated oak logs at two locations in the Taejo Mountain, Cheonan city, were used for fungal isolation. A total of 99 filamentous fungal isolates were obtained from the wood disk samples. Hypocrea spp., Trichoderma spp. and Penicillium spp. were identified based on morphological characteristics and nucleotide sequence analysis of translation elongation factor 1-alpha gene and ITS rDNA region. Trichoderma was the major fungal group. R. quercus-mongolicae, and P. koryoensis were not detected from the fumigated oak wood. Our work provided evidence that after three years of storage, the fumigated oak wilt-diseased logs should be no longer harmful source of oak wilt disease transmission.

• Research in Plant Disease
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• v.15 no.2
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• pp.63-67
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• 2009

Rice stripe virus (RSV) is one of Tenuivirus Group, which is carried by small brown planthopper. There is an outbreak of RSV in South Korea at 20Ot, and 2007. The infection caused by RSV had been investigated on weeds around the rice cultivated areas 13 region and 26 site including Jeonbuk Buan and Chungnam Seocheon. There have a doubt as to alternate host of RSV is total 15 Family and 50 Species including Gramineae 24 species of Duksaepul (Alopecurus aequalis), H. sativum var. vulgare etc.. There is identified the infected RSV in Festuca myuros, Alopecurus aequalis, Hordeum sativum var. vulgare, Trisetum bifidum, Echinochloa crus-galli var. crus-galli, Digitaria ciliaris among this species. Deulmuksae is the overwintering exotic weed which sprout in Autumn and wither in Spring and commonly growed as green manure crop or cover crop. In order to identify the infection rate furthermore, 111 samples which were collected at Buan Gyehwa-myeon region, and 50 samples from Seocheon Maseo-myeon in June, 2008, were ELISA tested. The results are 32 positives from Buan, 28.8% infection rate, 8 positives from Seocheon 16.0% infection rate. RSV infection of Deulmuksae is not reported currently, and follow report first describes the Deulmuksae as an alternate host of RSV.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.3
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• pp.390-400
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• 2010

This study is aimed to test physiological and hematological actions of Rheum palmatum through clinical pilot study optimized for usual oriental medicine prescription. Thirty-one cases were finally collected and the sample extract 100 $m{\ell}$ of Rheum palmatum (ERP) was administered two times in a day during 3 days and checked with blood CBC test, urinalysis, liver function test, abdominal X-ray as well as general diagnostic process of oriental medicine; pattern identification, assessment of shapes and constitution. The total toxic effective rate of ERP was 9.68% in 3 cases of the whole in case of consistent uneasy state in the subjective symptomatic assessment and aggravation of blood and urine examination. The relevant diagnostic factors were so-eum constitution and essence type subject, carapaces species, lung type in the aspect of Jisan shape theory. On the other hand, the positive effective rate of ERP was 29.03% manifesting improvement of vital signs or present illness and no abnormal changes of blood chemistry and urinalysis and simple abdomen radiology. The relevant diagnostic factors were tae-eum constitution, energy type subject, aves species, heart and liver type in Jisan's shape theory. And the other cases were manifesting no specific change through the administration of ERP. The ratio of the numbers of decrease and increase was 44:5 in the tenderness and hardness of abdominal palpation. But if the pattern identification doesn't comply with the aim of rhubarb application despite of constipation and abdominal pain, the tendeness and biochemical report was shown in abnormal change. The mean number of diarrhea by ERP was $16.77{\pm}6.95$ during 3 days after administration, and the frequent areas of abdominal pain were lower>middle>upper in order, and it meant the target site of ERP too. Besides, the toxic reaction against ERP was expressed highly in case of decrease in blood cell count and hemoglobin, hematocrit having blood deficiency syndrome. Likewise, the toxicity of ERP was influenced by pattern identification manifesting present disease condition and diagnostic factors of four constitutions, Jisan's shape theory collaterally. In conclusion, evaluation of herbal toxicity in order for using as a clinical guideline, various diagnostic pattern information and shape features like the above should be studied together with other pharmacologic toxicology test for the future.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.539-547
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• 2012

Volume survey for earthwork is conducted periodically at every month at large scaled construction sites for request payment for the construction. Currently, the earthwork volume is calculated on the overlapped drawing for two cross sections which were created by new and previous surveying data observed by GPS and TS. However the survey is required lots of time and expenses as it is a pin-point surveying method thus surveyors intend to get data only for the heavy undulated topographic features chosen by himself to save time and expenses. Consequently, it causes poor results due to low dense measurement as well as it's not matched with the results by another surveyors. As a result, the conflicts related in earthwork volume calculation often arises among the owner, contractors and sub contractors. In this study, we developed a method to get surveying data for fast and accurate volume calculation using 3D Mobile Laser System and conducted an application test. Also we carried out experiments for topographic survey using MLS to judge for the application additionally. The results showed that we could reduce a time for cross section survey from 48 hours to 2 hours and collected high dense data which have 0.2m interval instead of 3m interval compare with existing method. Also we could make a map which has high accuracy within 10cm in horizontal through topographic survey using MLS.

• Journal of the Mineralogical Society of Korea
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• v.16 no.4
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• pp.321-331
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• 2003

We researched the variation of mineral composition with depth and the Cu adsorption behavior of Hwangto in the Okjong area, Hadong. The 4 Hwangto samples were collected from depth 10 cm, 25 cm, 2∼3 m and under 3 m from surface, and analyzed using the X­ray Diffractometer. The Hwangto samples were mostly composed of clay minerals such as kaolinite and halloysite. Two samples from 10 cm and 25 cm contained Fe or Al hydroxide minerals, for example goethite or gibbsite. As depth increases, the content of quartz decreases but that of kaolinite increases. The amount of Cu removal was rapidly rised from pH 4, and reached about 90％ at pH 6 and above 90％ at pH 7. It is regarded that the trend of Cu removal was affected by the difference in mineral composition. It was relatively well matched between experimental value and calculated value by MINTEQA2 program in the case of high Cu concentration. From this study the precipitation has important role for the removal of Cu ions, particularly in the case of high Cu concentration. However, it was discord between experimental value and calculated one in the dilute concentration circumstances. The reason may be the mistake in parameters, insufficient reaction time, and inadequate consideration of reaction site in mineral surface.

• Journal of Conservation Science
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• v.29 no.4
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• pp.297-309
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• 2013

Iron objects become corroded at fast speed from the moment when they are excavated, so it is needed to control corrosion through processes of conservation treatment. However, re-corrosion mostly takes place in excavate iron objects, although they have already gone through the process of conservation treatment, and it is more difficult to carry out the second conservation treatment of re-corroded excavated iron objects than the first conservation treatment, and it requires a longer period of time to treat them as well. In this study, aims to discover factors of re-corrosion by scientifically analyzing corrosion products generated during the process of storage after the process of conservation treatment. The finished on conservation treatment of the iron artifacts, which were unearthed from three ancient site in Gyeongju by using the same conservation method between 2002 and 2009, re-corrosion condition observed on the packaging-iron artifacts. Focused on 9 target forged iron artifacts among them, this study analyzed the physical changes by mass measurement, naked-eye and microscopic observations and the chemical changes by SEM-EDS, XRD, IC and ICP analysis. The results show that the yellowish brown corrosion products formed on the facing surface of part dropped from the artifacts had different associated forms but acicular shape. In addition, the acicular shape became clearer as the color changed from red to yellowish brown. According to the process when the conservation treatment was completed, the mass of the artifacts increased in proportion to the corrosion products and the chloride ion ($Cl^-$) concentration had a tendency to increase relatively. ${\beta}$-FeOOH (akaganeite) was confirmed in the XRD analysis for the corrosion products of all the collected samples. As a result of ICP analysis, $Na^+$ and $Ca^{2+}$ components were confirmed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.261-269
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• 1989

Agricultural activities in Chejudo require more specialized weather services in this region. The meteorological information available from the Korea Meteorological Service (KMS) is limited in its areal coverage because the KMS stations are located along the narrow band of coastal area. topoclimatological technique which makes use of empirical relationships between the topography and the weather can be applied to produce reasonable estimates of the climatic variables such as air temperature and precipitation over remote land area where routine observations are rare. Presentation of these estimates in a from of fine-mesh grid map can also be helpful to upgrade the quality of weather services in this region. Altitude values of the 250 m grid points were read from a 1: 25000 topographic map and the mean altitude, the mean slope, and the aspect of the slope were determined for each 1 km$^2$ land area from these altitude data. Daily minimum air temperature data were collected from 18 points in Chejudo during the winter period from November 1987 to February 1988. The data were grouped into 3 sets based on synoptic pressure pattern. Departures from the KMS observations were regressed to the topographical variables to delineate empirical relationships between the local minimum temperature under specific pressure patterns and the site topography. The selected regression equations were used to calculate the daily minimum temperature for each 1 km$^2$ land area under the specific pressure patterns. The outputs were presented in a fine-mesh grid map with a 6-level contour capability.

• Economic and Environmental Geology
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• v.19 no.3
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• pp.231-237
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• 1986

Samples of porphyries, andesites, decites and sandstones were collected from 14 sites in order to study paleomagnetism and to determine K-Ar age in Guryongpo area. K-Ar age dating indicates that porphyries and volcanic rocks formed 41.7 and 22.7~19.4Ma, respectively. The mean direction of remanent magnetization for each site was generally well grouped after alternating field demagnetization. Both normal and reversed directions are present. The mean magnetic direction of the porphyries of Late Eocene and that of the volcanic rocks of Late Oligocene to Early Miocene have similar, easterly declinations. Overall magnetic direction is $Dm=43.8^{\circ}$, $Im=53.5^{\circ}$, ${\alpha}95=12.2^{\circ}$. the reliability of the observed paleomagnetic directions is ascertained by the presence of normal and reversed polarities. This is also conformed by the similarity of the declinations of the normal and reversed polarities. Observed easterly declinations in this area are attributed to local clockwise rotation of the land mass by approximately 40~50 degrees since early Miocene.

• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.42-49
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• 2008

For this study, we collected fishes of four times at the four site during June 2006 ${\sim}$ September 2007. In the result, the tolerance and omnivore species like a Carassius auratus and Pseudorasbora parva were largely dominated over all, and the sensitive species was not appeared at all except S4 in Shingu reservoir. This reservoir was appeared the simplified of trophic guild was shown in Shingu reservoir. Demonstrating that the omnivore species was occupied 78% of whole. According to the water chemistry data set obtained from the Korea Rural community & Agriculture corporation during $2002{\sim}2005$, the Shingu reservoir showed severe eutrophication and water pollution, therefore the increase of primary production and frequent algal blooms had been occurred. On the other hand, ecosystem health of reservoir was appeared "Fair${\sim}$Poor", and we judged that eutrophication and water pollution were due to this. Consequently, we thought that interception of nutrients and organic matters from the farmland and village and management of reservoir would be need, after this.