• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.87-98
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• 2015

Geochemical characteristics, water quality, $NO_3{^-}$ contamination and the origin of $NO_3{^-}$ were analyzed for the groundwater located at Ogcheon, Korea. The water qualities were weakly acidic to weakly alkalic and redox potentials indicated reduction condition. Compared to granitic rocks, metamorphic sedimentary rocks with intercalations of limestones and dolomites tended to be more effectively dissolved, resulting in higher pH and higher concentrations of dissolved ingredients. Contamination of heavy metals was not revealed. Geochemical reactions of carbonate rocks and influxes of artificial contamination ingredients seemed to simultaneously determine the geochemical characteristics and water qualities in the study area. From the results of ${\delta}^{15}N$ isotope analysis, the origin of $NO_3{^-}$ was estimated to be influenced dominantly by agricultural activities and human feces and urine.

• The Journal of Engineering Geology
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• v.33 no.4
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• pp.587-598
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• 2023

To assess the distribution and temporal changes in radon concentration within a region in Yeonpung-myeon, Goesan-gun, known for elevated groundwater radon levels, we conducted a series of analyses, measuring radon concentration and DTW (Depth to water table) at 2-month intervals over 12 cycles. The investigation covered 10 groundwater wells and one stream within the designated area. The groundwater in the central part of the region exhibited high radon concentrations, ranging from 37.0 to 2,675.2 Bq/L. Conversely, the peripheral zones displayed comparatively lower radon concentrations, ranging from 10.6 to 37.9 Bq/L. This variation is attributed to the presence of granite porphyry that intruded into the Okcheon Formation, forming a fracture zone and contributing to elevated radon levels in the central part. In contrast, the peripheral locations, located within the Okcheon Formation and away from the granite porphyry intrusion, demonstrated lower radon concentrations. The observed significant fluctuation in radon concentration in the central area is associated with its low-lying topography. The pronounced seasonal changes in groundwater levels contribute to the migration of shallow, low-radon groundwater into areas with higher radon concentrations, explaining the observed variations in radon levels within the central part of the studied area.

• The Journal of the Petrological Society of Korea
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• v.12 no.2
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• pp.79-99
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• 2003

Muscovite and biotite from 52 metasediments and 5 granites in the Hwasan area, the southwest of the Okcheon metamorphic belt and the Miwon-Jeungpyeong area, central Okcheon metamorphic belt were dated by the K-Ar and $^{40}$ Ar/$^{39}$ Ar methods. Muscovite and biotite ages from metapelitic and psammitic rocks (metasediments) of the Boeun and Pibanryeong units in the Hwasan area are concentrated in the mid-Jurassic (149-180 Ma). K-Ar and $^{40}$ Ar/$^{39}$ Ar ages for metapelitic and psammitic rocks of the Boeun and Pibanryeong units in the Miwon-Jeungpyeong area show complicated age distribution. Muscovite and biotite ages are classified by three groups, 142-194 Ma, 216-234 Ma, and 241-277 Ma. Younger (Cretaceous) ages occur only in metasediments close to Cretaceous granitic rocks in the southeastern region and the older ages of 216-277 Ma are restricted to the middle Part of the Jeungpyeong area. Most ages in the other area of the central Okcheon metamorphic belt fall between 142-194 Ma (Jurassic). K-Ar and $^{40}$ Ar/$^{39}$ Ar ages for granite from the northern part in the both the southwest and central Okcheon metamorphic belt also gave middle Jurassic ages (156-168 Ma). The similar ages from both metasediments and granites in the study areas indicate simultaneous cooling of both rocks to 300-350$^{\circ}C$ during the middle Jurassic. The state of graphitization of carbonaceous material of all metasediments in the study areas Indicates fully ordered graphite falling within a small range, from 3.353 to 3.359 ${\AA}$, which indicate amphibolite facies regional metamorphism. In the southern sector of the Boeun unit from the Hwasan area, metamorphic grade indicated by mineral paragenesis during regional intermediate-P/T metamorphism is greenschist facies. Whereas, the $d_{002}$ values for carbonaceous materials in the same sector show fully ordered graphite (ca. 500$^{\circ}C$) indicating amphibolite facies. This result with the concentration of mica ages of metasediments into the middle Jurassic, the presence of low-P/T thermal metamorphic zone (>500$^{\circ}C$) in the metasediments close to the Jurassic granite and the regional intrusion of Jurassic granites and their middle Jurassic intrusion and cooling ages may indicate the low-P/T regional thermal event during the early(\ulcorner)-middle Jurassic after main intermediate-P/T metamorphism which formed main mineral assemblage regionally in the study area. The regional thermal event failed, however, to reset the mineral assemblage of regional intermediate-P/T metamorphism except for narrow aureole (1-2 km) around Jurassic granite because e duration of thermal effect was relatively short by repid cooling of the Jurassic granite. In the middle part of the Jeungpyeong area, central Ogcheon metamorphic belt, muscovite and biotite K-Ar ages from 5 samples are 263-277 Ma and 241-249 Ma, respectively. An intermediate-P/T metamorphism is currently accepted to have occurred between 280 and 300 Ma. Therefore, the muscovite and biotite ages can be interpreted as cooling ages after Ml metamorphism indicating rapid cooling to ca 350$^{\circ}C$ between 280-300 Ma and 263-271 Ma, and biotite ages indicate slower cooling to ca. 300$^{\circ}C$ between 263-277 Ma and 241-249 Ma. However, more detail study is needed to confirm why the Permian to Triassic ages occur only in the middle Part of the Jeungpyeong area.a.

• Korean Journal of Environment and Ecology
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• v.37 no.4
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• pp.289-301
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• 2023

Forests within watersheds are essential in maintaining ecosystems and are the central infrastructure for constructing an ecological network system. However, due to indiscriminate development projects carried out over past decades, forest fragmentation and land use changes have accelerated, and their original functions have been lost. Since a forest's structural pattern directly impacts ecological processes and functions in understanding forest ecosystems, identifying and analyzing change patterns is essential. Therefore, this study analyzed structural changes in the forest landscape according to the time-series land cover changes using the FRAGSTATS model for the dam watershed of the Geum River upstream. Land cover changes in the dam watershed of the Geum River upstream through land cover change detection showed an increase of 33.12 square kilometers (0.62%) of forests and 67.26 square kilometers (1.26%) of urbanized dry areas and a decrease of 148.25 square kilometers (2.79%) in agricultural areas from the 1980s to the 2010s. The results of no-sampling forest landscape analysis within the watershed indicated landscape percentage (PLAND), area-weighted proximity index (CONTIG_AM), average central area (CORE_MN), and adjacency index (PLADJ) increased, and the number of patches (NP), landscape shape index (LSI), and cohesion index (COHESION) decreased. Identification of structural change patterns through a moving window analysis showed the forest landscape in Sangju City, Gyeongsangbuk Province, Boeun County in Chungcheongbuk Province, and Jinan Province in Jeollabuk Province was relatively well preserved, but fragmentation was ongoing at the border between Okcheon County in Chungcheongbuk Province, Yeongdong and Geumsan Counties in Chungcheongnam Province, and the forest landscape in areas adjacent to Muju and Jangsu Counties in Jeollabuk Province. The results indicate that it is necessary to establish afforestation projects for fragmented areas when preparing a future regional forest management strategy. This study derived areas where fragmentation of forest landscapes is expected and the results may be used as basic data for assessing the health of watershed forests and establishing management plans.

• Journal of agricultural medicine and community health
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• v.43 no.4
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• pp.258-269
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• 2018

Objectives: There was an outbreak of foodborne and waterborne disease among high school students at Okcheon in June, 2018. First attack occurred June $5^{th}$ but seven days later it was notified. The purpose of this investigation was to evaluate the pathogen of outbreak and cause of delayed notification. Methods: First, we did a questionnaire survey for 61 cases and 122 controls to find what symptoms they had and whether they ate foods or drank water from June $2^{nd}$ to June $12^{th}$. Second, we investigated the environment of cafeteria and drinking water. Third, we examined specimen of cases and environment to identify bacteria or virus. Results: Attack rate of this outbreak was 7.8%. Drinking water was strongly suspected as a source of infection in questionnaire survey but we could not find the exact time of exposure. Norovirus was identified in specimen of cases (2 students), drinking water (at main building and dormitory) and cafeteria (knife, dishtowel, hand of chef) Conclusions: We decided norovirus as the pathogen of this outbreak based on the clinical features of cases with diarrhea vomiting, abdominal pain and recovery within 2 or 3 days after onset, outbreak due to drinking water and microbiologic examination, And the cause of delayed notification might be the non-existence of the nurse teacher at that time and the lack of understanding of teachers on immediate notification under the outbreak. To prevent the delayed notification, notification system about outbreak of foodborne and waterborne disease in school is needed to be improved.

• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.95-102
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• 2003

Microalgae are a diverse group of photosynthetic organisms and abundant in every ecosystem in the biosphere. They are common in aqueous environments including marine, brackish and fresh waters and in some habitats that lack eukaryotic life such as some hot springs and highly alkaline lakes. Microalgal biotechnology that is focused on the microalgae-based production of a variety of useful materials such as pharmaceutical comfounds, health foods, natural pigments, and biofuels is considered as an important discipline with the development of biotechnology. In addition, the mass cultivation of microalgae can also contribute to improving the environmental quality by reducing the concentration of $CO_2$ which is one of major gases lead to global warming. Consequently, it seems that the microalgae can be used as an efficient, renewable, environmentally friendly source of high-value biomaterials such as chemicals, pigments, energy, etc. and the microalgal biotechnology will most likely represent a larger portion of modern biotechnology.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.540-547
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• 2011

This study was conducted to compare classification accuracy by tree species using QuickBird imagery for pixel- and segment-based classifications that have been mostly applied to classify land covers. A total of 398 points was used as training and reference data. Based on this points, the points were classified into fourteen land cover classes: four coniferous and seven deciduous tree species in forest classes, and three non-forested classes. In pixel-based classification, three images obtained by using raw spectral values, three tasseled indices, and three components from principal component analysis were produced. For the both classification processes, the maximum likelihood method was applied. In the pixel-based classification, it was resulted that the classification accuracy with raw spectral values was better than those by the other band combinations. As resulted that, the segment-based classification with a scale factor of 50% provided the most accurate classification (overall accuracy:76% and ${\hat{k}}$ value:0.74) compared to the other scale factors and pixel-based classification.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.203-215
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• 2015

The study aims to identify the degree and types of spatial recessions in Si/Gun and Eup/Myun units within Chungcheong region in South Korea to contribute to the efforts being made to diagnose the rural recession and the potentials. To this end, we analyzed 27 Sis and Guns to identify the degree of recession and potentials of rural areas in Chungcheong region. We also carried out the diagnosis and K-Means Clustering on 274 Eups and Myuns, smaller administrative units, to figure out the types and characteristics of the rural recessions. In case of the analysis targeting the Sis and Guns, a relatively high degree of rural recession was found in Cheongyang, Seocheon and Taean for Chungcheongnam-do, and in Danyang and Goisan, as well as in Boeun, Okcheon and Youngdong - which are collectively called as 'Southern 3 Areas in Chungcheongbuk-do' as they are conventionally known by their high degree of rural recession. According to the results of the clustering analysis carried out on the 166 Eups and Myuns, there were five outstanding clusters. They were; areas with housing deterioration (29), areas with poor economic foundation (16), areas with poor accessibility to central areas (42), areas with poor residential environment (51) and areas with aged population (28). The findings and results of the present study are likely to serve as a basis for the design and enforcement of forthcoming rural area activation policies. Also, it would be highly recommended that a more comprehensive diagnosis is taken from a community-level perspective and policy suggestions and strategies tailored for rural communities are further discussed.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.1
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• pp.88-95
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• 2021

Aucklandia lappa Decne., a traditional herbal medicine, has been used to treat various diseases, including asthma, coughs, rheumatism, and diarrhea. In the present study, the effects of the oral administration of Aucklandia lappa Decne. extract on hair growth was investigated in hair-removed mice. A 70% ethanol extract of Aucklandia lappa Decne. (ALD) was prepared, and the extraction yield and total polyphenol content of ALD were measured as 27.30±0.01 and 28.39 mg gallic acid equivalent (GAE)/g, respectively. The oral administration of ALD to hair-removed CL57BL/6 mice for six weeks had no significant effects on food intake and body weight changes. Biochemical and histological examinations also showed that the oral administration of ALD for six weeks had no significant effect on the liver and kidney functions. On the other hand, hair growth was significantly higher in the ALD group than the control group and the Pancidil group (positive control). In addition, the number of hair follicles and the degree of collagen production in the dermis were significantly higher in the ALD group than in the control and pancidil groups. These results suggest that ALD is a potential source of nutricosmetics with hair growth-promoting effects.

• Journal of National Security and Military Science
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• s.13
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• pp.137-658
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• 2016

1. Movement of the leaders of the Silla army The leaders of the Silla army traveled from Gyeongju(경주) to Icheon (이천), Deokjeokdo(덕적도) Island, and Hwangsanwon(황산원) during the period of the Against Baekje(백제) War that began in 660. Movement route between Gyeongju and Icheon : Gyeongju(경주)-Daegu(대구)-Gumi(구미)-Gimcheon(김천)-Chupungryeong(추풍령)-Geumdol Fortress(금돌성)-Boeun(보은)-Jincheon(진천)-Juksan(죽산)-Bubal-eup(부발읍) Movement route between Bubal-eup and Deokjeokdo Island : Bubal-eup(부발읍)-Ipo(이포) Ferry-Haengju(행주) Ferry-Palmido (팔미도) Island-Seonjaedo(선재도) Island-Yeongheungdo(영흥도) Island-Pido(피도) Island-Soyado(소야도) Island-Deokjeokdo(덕적도) Island Movement route between Deokjeokdo Island and Hwangsan: Deokjeokdo(덕적도) Island-Danghangpo(당항포)-Jincheon(진천)-Boeun (보은)-Okcheon(옥천)-Geumsan(금산)-Tanhyeon(탄현)-Hwangsan (황산)-Ganggyeong(강경)-Buyeo(부여) 2. Movement of the combat units of the Silla army Jincheon area : 4,325 persons of the Geupdang unit(急幢) and 611 persons of the Kaegeumdang unit(罽衿幢) were deployed. These units moved from Jincheon to Cheongju, Yeongi, and Gongju, and contained Ungjin Fortress(熊津城) (6,650 Baekje troops). Boeun area : 4,763 persons of the Daedang(大唐) unit, 3,548 persons of the Hajujeong unit(下州停), 3,017 persons of the Namcheonjeong unit(南川停), and 4,500 persons of the Saseoldang unit(四設幢) were deployed. These units moved from Boeun(보은) to Okcheon(옥천), Geumsan(금산), Tanhyeon,(탄현) and Hwangsan(황산). Geumdol Fortress area : 3,753 persons of the Sangjujeong unit(上州停), 5,762 persons of the Seodang unit(誓幢), 3,753 persons of the Guidang unit(貴幢), and 5,562 persons of the Nangdang uni(郎幢)t were deployed. These units moved from Geumdol Fortress to Hwanggan(황간), Yeongdong(영동), Geumsan(금산), Tanhyeon(탄현), and Hwangsan(황산). Jirye area: 3,017 persons of the Eumrihwajeong unit(音里火停) and 3,017 persons of the Ehwahyejeong unit(伊火兮停) were deployed. These units moved from Jirye(지례) to Juchiryeong(走峙嶺), Mupung (무풍), Muju-eup(무주읍), and Bunam-myeon(부남면) in Muju-gun. Goryeong area: 3,017 persons of the Samryanghwajeong unit(三良火停) and 3,017 persons of the Sosamjeong unit(召參停) were deployed. These units moved from Goryeong(고령) to Geochang(거창), Hamyang(함양), Namwon(남원), Sunchang(순창), and Jeongeup(정읍). 3. Movement of the Tang army Dangjin area(당진 방면) : 1,000 persons were deployed. These units moved from Dangjin(당진) to Myeoncheon(면천), Yesan(예산), and Imjon Fortress(임존성). Garijeo area(가리저 방면) : 1,000 persons were deployed in the Garijeo(加里渚) area. These units moved from Garijeo(가리저) to Myeoncheon(면천), Yesan(예산), and Imjon Fortress(임존성). Geumganggu area(금강구 방면) : 000 persons were deployed. These units moved from Geumganggu(금강구) to Ganggyeong(강경) and Sabi Fortress(사비성). 4. Baekje military deployment Total troops of the Baekje army : There were 60 thousand Baekje troops according to the Old Book of Tang(舊唐書). Troop deployment by the Baekje army: 62,230 persons were deployed in 15 regions: 1,000 in Dangjin(당진), 1,000 in Garijeo(가리저), 6,120 in Imjon Fortress(임존성), 1,120 in Namjam Fortress(남잠성), 1,350 in Dooryangyun Fortress(두량윤성), 870 in Wangheungsajam Fortress(왕흥사잠성), 6,650 in Ungjin Fortress(웅진성), 1,120 in Jinhyeon Fortress(진현성), 1,000 in Dooshiwonak(두시원악), 1,000 in Irye Fortress(이례성), 5,000 in Gosaburi Fortress(고사부리성), 5,000 in Gujiha Fortress(구지하성), 3,000 plus 3,000 in Gibeolpo and Yangan(기벌포 양안), 5,000 in Deukan Fortress(득안성), and 20,000 in Sabi Fortress(사비성).