• Economic and Environmental Geology
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• v.52 no.5
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• pp.459-469
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• 2019

We present a quantitative evaluation of density, vesicularity and microtextures for coarse lapilli collected from the Jugam Scoria Deposits, northeastern Ulleung Island. Lapilli from the deposits have modal vesicularities of 61% in the lower part and 67% in the upper part, and vesicle populations dominated by non-interconnected subround vesicles. Clasts of modal vesicularity have margin-parallel zonation, with subaerially quenched rims interpreted to preserve "syn-fragmentation" magmatic textures in microlite-free sideromelane rims, grading "post-fragmentation" tachylitic interiors with vesicle and microlite textures that progressively coarsen from rim to interior. Degassing scenarios are linked to syn-fragmentation vesicle textures to demonstrate that the magmas degassed in dominantly closed systems. And diffusion-controlled cooling rates of trachyandesitic pyroclasts in contact with atmosphere are linked to post-fragmentation evolution of vesicle and microlite textures to infer about transportation and dispersal of the pyroclasts in low shooting jets. These textural analyses show that the Jugam eruptions were strictly applied to the strombolian type, analogous to the hawaiian type among any classical subaerial eruption type.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.509-514
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• 2015

Indicators of environmental conditions qualitatively and quantitatively describe the state of the environment and natural resources, and the OECD (Organization for Economic Cooperation and Development) has initiated and suggested AEIs (Agri-Environmental Indicators) to assess trends over time of the effects of agriculture on the environment and the effectiveness and efficiency of agricultural and environmental policy measures since 1990's. This study aims to develop the state indicators of water quality for agricultural water, surface and groundwater, to evaluate the environmental impacts of agricultural activities and policies by qualifying the environmental levels of a nation. Status indicators were calculated according to the agricultural water quality standards of OECD and Korea, and their trends were analyzed over time. Particularly, nitrate ($NO_3{^-}$) status indicators of ground water in 2013 were significantly lower than the ones in 2000. Overall, the water quality indicators of surface water in 2013 were higher than the ones in 2012, except for pH and DO. The groundwater quality indicators in 2013 were lower than those of previous years. The optimal management indicators were calculated to assess agricultural surface water and groundwater quality. The findings of this study indicated that the state indicators could play a significant role to establish policies and procedures for managing and conserving water resources. This study also discussed water pollution caused by agricultural and industrial effluents.

• Journal of Climate Change Research
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• v.8 no.4
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• pp.415-424
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• 2017

This study was conducted to estimate carbon stocks of Pinus densiflora with drawing volume of trees in each tree height and DBH applying the suitable stem taper equation and tree specific carbon emission factors, using collected growth data from all over the country. Information on distribution area, tree age, tree number per hectare, tree volume and volume stocks were obtained from the $5^{th}$ National Forest Inventory (2006~2010) and Statistical yearbook of forest (2016), and method provided in IPCC GPG was applied to estimate carbon stock and uptake. Performance in predicting stem diameter at a specific point along a stem in Pinus densiflora by applying Kozak's model, $d=a_{1}DBH^{a_2}a_3^{DBH}X^{b_{1}Z^2+b_2ln(Z+0.001)+b_3\sqrt{Z}+b_4e^z+b_5(\frac{DBH}{H})}$, which is well known equation in stem taper estimation, was evaluated with validations statistics, Fitness Index, Bias and Standard Error of Bias. Consequently, Kozak's model turned out to be suitable in all validations statistics. Stem volume table of P. densiflora was derived by applying Kozak's model and carbon stock tables in each tree height and DBH were developed with country-specific carbon emission factors ($WD=0.445t/m^3$, BEF = 1.445, R = 0.255) of P. densiflora. As the results of analysis in carbon uptake for each province, the values were high with Gangwon-do $9.4tCO_2/ha/yr$, Gyeongsandnam-do and Gyeonggi-do $8.7tCO_2/ha/yr$, Chungcheongnam-do $7.9tCO_2/ha/yr$ and Gyeongsangbuk-do $7.8tCO_2/ha/yr$ in order, and Jeju-do was the lowest with $6.8tC/ha/yr$. Total carbon stocks of P. densiflora were 127,677 thousands tC which is 25.5% compared with total percentage of forest and carbon stock per hectare (ha) was $84.5tC/ha/yr$ and $7.8tCO_2/ha/yr$, respectively.

• Journal of Korea Entertainment Industry Association
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• v.15 no.1
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• pp.143-152
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• 2021

The extremely isolated uninhabited island at the end of the West Sea in South Korea called "The Gyeokryeolbi Yeoldo" has recently begun to be managed by the government under the influence of public opinion demanding the island to be strictly protected. The island was created 70 million years ago by volcanic activities. So it is older than the birth history of Jeju Island, which is estimated to have been born about a million years ago. This study has focused on providing the basis for imagetelling and storytelling of the Gyeokryeolbi Yeoldo, known for its important value by exploring the cultural resources of the island. For the research, the ethnography including in-depth local interview and on-site investigation have been applied for 3 years from February 2018 to December 2020 in Taean, Chungnam Province, where the island is located. To analyze the cultural resources of this island, the resource classification model has been designed and used, which is modified from Valentine (2001) and Chi-ho Nam (2007). As a result, the "tangible cultural resources (TCR)" including various remains found on the island were mainly symbols of cultural bridge in the history of Korea-China exchange, and the spiritual land of life-saving. Also "intangible cultural resources (ICR)" extracted from the island were focused on the images of life protection, safety, bravery, and romance. Based on this study, the core concept of identity to be applied when refurbishing the island with a prominent cultural placeness( "sense of place") can be proposed as "a cultural ecological island centered on the Circular Yellow Sea that ruminates memories of love."

• Journal of Ecology and Environment
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• v.45 no.4
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• pp.277-286
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• 2021

Background: As trade increases, the influx of various alien species and their spread to new regions are prevalent and no longer a special problem. Anthropogenic activities and climate changes have made the distribution of alien species out of their native range common. As a result, alien species can be easily found anywhere, and they have nothing but only a few differences in intensity. The prevalent distribution of alien species adversely affects the ecosystem, and a strategic management plan must be established to control them effectively. To this end, hot spots and cold spots were analyzed according to the degree of distribution of invasive alien plants, and major environmental factors related to hot spots were found. We analyzed the 10,287 distribution points of 126 species of alien plants collected through the national survey of alien species by the hierarchical model of species communities (HMSC) framework. Results: The explanatory and fourfold cross-validation predictive power of the model were 0.91 and 0.75 as AUC values, respectively. The hot spots of invasive plants were found in the Seoul metropolitan area, Daegu metropolitan city, Chungcheongbuk-do Province, southwest shore, and Jeju island. Generally, the hot spots were found where the higher maximum temperature of summer, precipitation of winter, and road density are observed, but temperature seasonality, annual temperature range, precipitation of the summer, and distance to river and sea were negatively related to the hot spots. According to the model, the functional traits accounted for 55% of the variance explained by the environmental factors. The species with higher specific leaf areas were more found where temperature seasonality was low. Taller species preferred the bigger annual temperature range. The heavier seed mass was only preferred when the max temperature of summer exceeded 29 ℃. Conclusions: In this study, hot spots were places where 2.1 times more alien plants were distributed on average than non-hot spots (33.5 vs 15.7 species). The hot spots of invasive plants were expected to appear in less stressful climate conditions, such as low fluctuation of temperature and precipitation. Also, the disturbance by anthropogenic factors or water flow had positive influences on the hot spots. These results were consistent with the previous reports about the ruderal or competitive strategies of invasive plants instead of the stress-tolerant strategy. The functional traits are closely related to the ecological strategies of plants by shaping the response of species to various environmental filters, and our result confirmed this. Therefore, in order to effectively control alien plants, it is judged that the occurrence of disturbed sites in which alien plants can grow in large quantities is minimized, and the river management of waterfronts is required.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.1
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• pp.23-27
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• 2022

Disposable wet wipes provided by general restaurants in the Jeju Special Self-Governing Province were evaluated for compliance with the labeling requirements and the degree of bacterial contamination set by the Ministry of Food and Drug Safety. Of the 32 types of disposable wipes, five types of disposable wipes did not indicate the name and location of the business office of the manufacturer. Only 12 types of wet wipes were marked with the date of manufacture and expiration date. Bacterial contamination was seen in 9 types of wet wipes through bacterial culture but these were absent in the remaining 23 types (71.9%). The results of the antimicrobial susceptibility test for the 9 identified strains showed no methicillin-resistant coagulase-negative staphylococci (MRCNS) or multidrug-resistant bacteria. Through this study, it is recommended that the date of manufacture and expiration date must be indicated on the surface of disposable wet wipes designated as hygiene products, and clean uncontaminated wet wipes must comply with storage standards. In addition, the results are expected to contribute to the enhancement and improvement of hygiene management supervision, personal hygiene management, and an improvement in national health.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5D
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• pp.605-610
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• 2009

The either satisfaction levels or limits of tolerance levels felt by the users in the certain space/region should be examined for measuring social capacity on the total amount of vehicles. The reliability of measuring social carrying capacity depends primarily on decreasing the strategic responding biases. To induce the honest responses to preferences, Dichotomous Choice which is specifically known as the Double-Bounded Dichotomous Choice was adopted in this research to suggest the measurement methodology of social carrying capacity on the total amount of vehicles in U-do island. The empirical test was carried out the U-do island, an administrative district of Jeju Special Self-Governing Province. The number of vehicles satisfied by the 10% of residents was 390 and the satisfactory vehicle number was decreased to 132 extended to 90% of residents. This research, based on the political decision making criteria, set up the social carrying capacity in U-do island. The vehicle number satisfied by 50% of residents was 227, which meant the same number of residents turn to be supporter in case of political actions.

• Health Policy and Management
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• v.34 no.1
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• pp.17-25
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• 2024

Background: This study aimed to assess the appropriate allocation of emergency medical beds across 17 provinces and presume the economic benefits associated with such allocation. Methods: To estimate the optimal allocation of emergency medical beds by province, data from the Statistics Korea's "cause of death statistics (2014-2021)," regional statistics on "area, population, gender, age," and "population projections" were utilized. The "number of emergency beds by city and district" provided by the Health Insurance Review and Assessment Service was also used. In estimating the economic benefits of preventing avoidable emergency deaths due to the expansion of emergency medical facilities, guidelines from the Korea Development Institute and the Korea Transport Institute were referenced to calculate the wage loss costs associated with emergency deaths and estimate the economic benefits. Results: The optimal ratio of emergency medical beds allocation by region was highest in Gyeonggi, Seoul, Gyeongnam, Gyeongbuk, and Busan, while Daejeon, Jeju, and Sejong showed lower ratios. Additionally, the prevention of avoidable deaths and economic benefits resulting from the increase in emergency medical facilities were highest in Gyeonggi, Seoul, Gyeongbuk, Gyeongnam, and Busan. However, when standardized by population, the prevention of avoidable deaths and economic benefits were analyzed to be highest in Gyeongbuk, Chungnam, Jeonnam, Gyeongnam, and Busan. Conclusion: The results of this study can serve as foundational data for future policy measures aimed at addressing the imbalance in the supply of emergency medical facilities across regions. Considering regional characteristics in the distribution of emergency medical facilities is expected to ultimately increase the efficiency of national finances and yield economic benefits.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.20-29
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• 2024

Hemitripterus villosus, a promising aquaculture fish species, is facing declining stocks. This study aims to provide normative standards for skeletal development to address persistent skeletal deformities in farmed fish. Specimens utilized in the study underwent artificial insemination with captured fish, and the resulting larvae and fry were preserved in a formalin solution. The skeletal ossification process commenced immediately after hatching, affecting the parasphenoid, premaxillary, maxillary, and dentary structures at an average total length of 13.65±0.71 mm (n=5). By sixty-five days post-hatching, ossification extended to the ethmoid and supraorbital, completing the head's development at an average total length of 21.24±0.50 mm (n=5). Clavicle ossification occurred at seven days post-hatching, corresponding to an average total length of 14.61±0.52 mm (n=5). At forty-four days post-hatching, the ossification of 4 actinosts took place, completing the shoulder girdle, with an average total length of 18.15±0.61 mm (n=5). Vertebral ossification initiated at ten days post-hatching, with an average total length of 14.80±0.65 mm (n=5). By fifty-four days post-hatching, 39 vertebral columns were ossified, reaching an average total length of 18.67±0.54 mm (n=5). Vertebral development was complete at sixty days post-hatching, with an average total length of 20.25±0.45 mm (n=5). This study sheds light on the skeletal development of H. villosus, providing valuable standards and fundamental data for understanding skeletal deformities in this species.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.641-646
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• 2013

Chemical properties of agricultural soils in Korea have been investigated at four-year interval in order of paddy, polytunnel, upland, and orchard soils since 1999; polytunnel soils were investigated over the whole country in 2000, 2004, 2008, and 2012. Polytunnel soils were taken from the surface (0-15 cm) and subsurface (15-30 cm) at 2,651, 1,274, 1,374 and 1,374 sites in all provinces of South Korea. One hundred sampling sites located in more than 400 m altitude were additionally investigated in 2008 and 2012. Average of soil chemical properties in 2012 except Jeju province were 6.6 for pH, 3.2 dS $m^{-1}$ for EC, 37 g $kg^{-1}$ for organic matter (OM), 1,049 mg $kg^{-1}$ for available (Avail.) phosphate, 1.58 $cmol_c\;kg^{-1}$ for exchangeable (Exch.) K, 10.6 $cmol_c\;kg^{-1}$ for Exch. Ca, and 3.3 $cmol_c\;kg^{-1}$ for Exch. Mg. Except pH, averages of all chemical properties exceeded the upper limit of optimal range. The median values except pH showed a lower value than the averages. The pH, OM and Exch. Ca had slightly increased from 6.3 to 6.6, from 34 to 37 g $kg^{-1}$, and from 7.7 in 2000 to 10.6 $cmol_c\;kg^{-1}$ in 2012, respectively. The order of sample ratios exceeding the optimal range were Avail. $P_2O_5$ (83%) > Exch. Ca (80%) > Exch. K (70%) > Exch. Mg (65%) > EC (55%) > OM (48%) > pH (29%) in 2012. The order of sample ratios below the optimal range was OM (25%) > Exch. K (25%) > pH (20%), Exch. Mg and Avail. $P_2O_5$ (9%) > Exch. Ca (6%) in 2012. The excessive proportion of pH, Exch. Ca, Exch. Mg and OM slightly increased, while the insufficient proportion of those decreased. Approximately 55% of polytunnel soils exceeding EC 2 dS $m^{-1}$ was evaluated with salt accumulated soils having the risk of growth disorder of crops. Nutrient contents in polytunnel soils in Korea showed high level especially Avail. $P_2O_5$ and Exch. cations. Therefore, recommended fertilization based on soil testing or plant testing is needed for soil nutrient management.