• Journal of Korean Society of Coastal and Ocean Engineers
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• v.14 no.4
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• pp.295-307
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• 2002

Water temperature, salinity, and DO concentration were measured vertically in the Chinhae-Masan Bay over the course of 1 year. The characteristics of the stratification were analysed using the measured water temperature and salinity data. The vertical DO concentration changes were also analysed through consideration of the degree of stratification and the level of sediment pollution. The results of the analyses show that the thermal stratification appears just before April and disappears after October. The salinity differences between the surface and the bottom were 3.9(equation omitted), 9.3 (equation omitted), 4.3(equation omitted) in April, August, and October, respectively. The DO concentration change averaged over water depth was 2.6(mg/L) in April; 8.3(mg/L) in June: 5.9(mg/L) in August; 7.2(mg/L) in September; and 4.4(mg/L) in October. The DO concentration changes were closely related to the levels of contamination and also to the effect of the mass-transfer inhibition between the surface and bottom layers due to the thermal and density stratification.

• Korean journal of applied entomology
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• v.20 no.1 s.46
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• pp.51-58
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• 1981

Hitherto 44 species belonging to 19 families of spiders have been reported at Ulreung-do on the East Sea. Korea. The authors have investigated spider fauna, through out the Ulreung-do, during July 25, August 3. 1975 and July 30, August 7, 1980. The foundings were as followings. 1) In this report, 132 species of 74 genera, including 3 undetermined species, belonging to 25 families of spiders are tabulated by the aid of published data and collections of the authors. Eighty six species are added to the fauna, of which 2 species are new to Korea. as follows; Porrhomma montanum Jackson. 1918, Clubiona neglecta O.P. Cambridge, 1862. The spider fauna of Ulreung-do includes 18 nothern species $(14.0\%)$, 8 southern species $(6.2\%)$. 7 cosmopolitan species $(5.4\%)$ and 84 Palaearctic temperate species $(65.1\%)$. The predominant species are Araneids. Thridiids, especially Cyclosa japonica Boes. et Str. are found in large numbers all over this island. Linyphiids and Lycosids are relatively few in number. 3) The common species to comparative area and foreign countries are as follows; Ulreung-do/Jookbyeon...76 species$(43.3\%)$ Ulreung-do/Jeju-do...95 species$(40.6\%)$ Ulreung-do/Heuksan do...61 species$(35.7\%)$ Ulreung-do/Deogjeog-do...51 species$(31.7\%)$ Ulreung-do/Tsushima Isl....71 species$(30.3\%)$ Ulreung-do/Japan...112 species$(11.3\%)$ Ulreung-do/main China...59 species $(6.5\%)$ 4) The ecological distribution are as follows; The seashore region...81 species$(62.8\%)$ The evergreens region...73 species$(56.6\%)$ The highiands region...64 species$(49.6\%)$ The valleys region...49 species$(38.0\%)$ The basin region...23 species$(17.8\%)$ 5) The noticeable one of geographical distribution in this island, are as follows; Nesticus quelpartensis Paik et Namkung, 1969, Conoculus simboggulensis Paik, 1971.

• Journal of Internet Computing and Services
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• v.22 no.2
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• pp.51-58
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• 2021

Three degrees of freedom plus(3DoF+) and six degrees of freedom(6DoF) system, which supports a user's movements in graphical and natural scene-based virtual reality, requires multiple high-quality and high-resolution videos to provide immersive media. Previous video quality assessment methods are not appropriate for the 3DoF+ and 6DoF system assessment because different types of artifacts occur in these systems which are not shown in the traditional video compression. This paper provides the performance assessments of several quality assessment methods in 3DoF+ system. Furthermore, this paper presents a super metric, which combines multiple quality assessment methods, thereby it showed a higher correlation coefficient with the subjective quality assessment than the previous methods. Experimental results on 3DoF+ immersive video showed 0.4513 gain on correlation coefficient with subjective quality assessment compared to that of peak signal-to-noise ratio(PSNR).

• Human Ecology Research
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• v.61 no.2
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• pp.233-245
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• 2023

The aim of this study was to identify community-level childcare infrastructure for infants and toddlers and to use the data to categorize community types using K-Means cluster analysis with spatial constraints. Seven indicators of childcare resource supply were used for the purpose of categorization and the results revealed six types of community cluster. Communities in the Type 1 cluster provided sufficient parks, libraries, and kindergartens, but lacked pediatric facilities and private education institutions. This cluster comprised small cities and rural areas in Gangwon-do, Gyeongsangbuk-do, Chungcheongbuk-do, and Jeollabuk-do. The Type 2 cluster had numerous pediatric facilities and childcare centers, but lacked other childcare infrastructure. This comprised small and medium-sized cities in Gyeonggi-do, some areas in Chungcheongnam-do, Chungcheongbuk-do, and Gangwon-do bordering Gyeonggi-do. The Type 3 cluster comprised Busan, Daegu, and Gyeongsangnam-do, but had insufficient childcare infrastructure as a whole. Type 4 had the largest number of childcare centers, libraries, and private education institutions and comprised Jeollabuk-do, areas near Gwangju, and Jeju-do. Type 5, consisting of Seoul, Incheon and the southern part of Gyeonggi-do had many pediatric facilities and certified childcare centers, but lacked other childcare infrastructure. Type 6, being the rural areas and islands in Jeollanam-do, had sufficient kindergartens, but other infrastructure was insufficient. These results are expected to provide local government with policy implications in terms of relieving the childcare burden on residents with infants and toddlers.

• Journal of The Geomorphological Association of Korea
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• v.26 no.4
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• pp.33-45
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• 2019

The shore platforms at Dok-do could be an important and clear indicator showing dimensional reduction of Dok-do. Especially flat type shore platforms are distributed in the southern coast of Dok-do island, composed of weak rocks against erosional resistance like interbedded lapilli tuff and massive tuff breccia. The distribution of shore platform is partially related to the wind direction at Dok-do island. The primary SW- and secondary SE winds are representative among wind directions at Dok-do, maintaining from spring to the autumn. Therefore, wide shore platforms could be developed by waves approaching from SW and SE directions in the southern coast of Dok-do. The sea stacks like Gunham-rock, Neopdeok-rock, Keungaje-rock and Jakeungaje-rock on the western coast are also considered to be formed by wave erosion from the SE direction. The shore platforms in the southern coast of Dok-do island were developed since ca. 7,000 yr. BP, when sea level raised almost to the present level. The average extension speed of shore platform was calculated to 4.0mm/y, because the broadest shore platform with the width ca. 28m was extended for ca. 7,000 years. The width's dimension of shore platform at Dok-do reflects a slow extension rate in the present, although erosional process will be faster with the sea level rise in the future.

• The Journal of the Petrological Society of Korea
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• v.15 no.2 s.44
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• pp.72-80
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• 2006

We report new K-Ar ages of volcanic rocks from Ulleung-do and Dok-do islands located at the middle of the Korea Sea; $3.67{\pm}0.40\sim1.89{\pm}0.29$ Ma for the Dok-do and $8.07{\pm}0.39\sim0.51{\pm}0.07$ Ma for the Ulleung-do. Such ages reveal that igneous activities of both Dok-do and Ulleung-do extend longer than previously reported. It is likely that igneous activity of Ulleung-do started as early as $8.07{\pm}0.39$ Ma which is much older than age known currently, and latest eruption and intrusion of trachyte of Dok-do lasted until $1.89{\pm}0.29$ Ma, which overlaps previously reported igneous activity of Ulleung-do. However, it seems that the main volcano-building stage of Ulleung-do started after 2.7 Ma and igneous activities of Dok-do were finished mostly before then, which suggests that Dok-do was farmed before Ulleung-do in the respect of main stages of volcano-building. Such explanation agrees well with the hypothesis that southeastern seamounts, Dok-do and Ulleung-do were sequentially generated by relatively fixed hotspot.

• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.303-309
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• 2021

Background: Humidifier disinfectant is a biocidal product used in the water tanks of humidifiers to prevent the growth of microorganisms. Although there are a huge number of cases of reported humidifier disinfectant-related health effects across the entire Korean population, their numbers are distributed differently depending on the region. Objectives: This study aimed to investigate the regional distribution of enrollment cases who reported humidifier disinfectant-related health effects. Methods: This study used data on 6,240 subjects who experienced humidifier disinfectant-related health effects and who enrolled their cases which is conducted by the Korea Ministry of Environment. We examined the regional distribution of the enrolled cases based on sixteen administrative divisions and assessed the: 1) crude number; 2) proportional rate; and 3) age-standardized proportional rate of enrollment by region. Results: When we examined the crude number of enrollments by region, the highest number were in Gyeonggi-do Province (n=1,896), followed in order by Seoul (n=1,405), Incheon (n=436) Busan, Daegu, Gyeongsangnam-do Province, Daejeon, Chungcheongnam-do Province, Gyeongsangbuk-do Province, Jeollabuk-do Province, Gwangju, Chungcheongbuk-do Province, Gangwon-do Province, Jeollanam-do Province, Ulsan, and Jeju-do. When we examined proportional rate of the regional enrollment (cases per 100,000 population), Daejeon (n=16.2) was the region with the highest rate, followed in order by Gyeonggi-do Province (n=16.1), Incheon-do Province (n=15.9), Seoul, Daegu, Gwangju, Jeollabuk-do Province, Chungcheongnam-do Province, Busan, Chungcheongbuk-do Province, Gangwon-do Province, Gyeongsanbuk-do Province, Gyeongsangnam-do Province, Ulsan, Jeju-do, and Jeollanam-do Province, which is inconsistent with the order in terms of crude numbers. However, when we examined the age-standardized proportional rate of regional enrollment (cases per 100,000 population), their ranked distribution is consistent with the crude rate. Conclusions: This study observed that the regional distribution of the enrolled cases who reported humidifier disinfectant-related health effects is inconsistent with the regional distribution of the proportional rate of enrollment cases, which may be caused in part by the volume of the inherent population of each region.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.278-279
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.09a
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• pp.53-53
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• 2019

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.156-156
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• 2022