• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.76-85
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• 2023

This study aimed to understand social interactions by observing the courtship and attack behavior between individuals of 15 (6 females and 9 males) Reeves' turtle (Mauremys reevesii) in captivity in the Wolchulsan National Park. CCTV was installed in the study area from May 18, 2020 to October 19, 2020 and recorded 3 days a week (24 hours/day) for a total of 64 days and analyzed at intervals of 10 minutes per hour. Male turtle courtship was observed 884 times in total, with the heaviest females receiving the highest courtship frequency (357 times) and the smallest females receiving the least courtship (3 times). Of a total of observed 259 aggressive behaviors, 30 were for female to female, 81 for male to male, and 148 for female to male. Dominance hierarchy identified based on the result ranked females higher overall than males, and the larger the body, the higher the ranking. This study was the first in Korea to confirm individuals with high probability of reproduction through the frequency of courtship in the Reeves' turtle and investigate dominance hierarchy according to attack behavior. Our results can be used as reference behavioral data for managing and protecting the endangered Reeves' turtles and will help us understand their social structure.

• Korean Journal of Environmental Biology
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• v.41 no.2
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• pp.138-144
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• 2023

The main factor of biodiversity decline in major biological populations around the world is invasion of alien species. To protect native species, it is necessary to manage alien species. Recently, to eradicate ecosystem disturbance caused by alien species in Korea, many efforts have been made to capture individuals using nets and purchase captured individuals. However, there is no standard for classifying species due to the form of nest site or external characteristics of eggs of freshwater turtles. Thus, Mauremys reevesii eggs might be discarded due to mistaking as eggs of alien turtles. Based on more data, this study aims to compare and analyze external differences among eggs of Trachemys scripta elegans, Pseudemys concinna, and M. reevesii and use them as reference materials in the process of eradicating alien turtles. This study measured characteristics of eggs of the three turtle species. As a result of comparison, all variables of external characteristics of alien turtles and M. reevesii eggs showed significant differences. The shape of egg was also different, with eggs of T. scripta elegans and P. concinna showing a bicone shape and those of M. reevesii showing an ellipsoid shape. In conclusion, based on results of previous studies and the present study, eggs of M. reevesii, T. scripta elegans, and P. concinna are different in shape and structure. Thus, it is possible to distinguish between M. reevesii and invasive alien turtle using their eggs.

• 한국노년학
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• v.39 no.2
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• pp.213-229
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• 2019

The purpose of this study was to examine various factors influencing the needs of Seoul's newly implemented outreach community services for older adults, and to suggest the direction of the outreach community health services in Seoul. A multi-level regression was conducted using data collected by face-to-face interviews from 1,000 individuals aged 65 and 70 in 17 districts, where participated in the Seoul's outreach community services. The results demonstrated that socioeconomic status (higher income and living alone), health status (having multiple chronic conditions and depression, lower health literacy), limited experience of the outreach community services, and low government trust at the individual level were associated with higher unmet need for the community outreach services. In addition, shorter participation period of the outreach services and financial independency at the district level were associated with higher unmet need for the services. The findings from this study implies the need for improving the quality of services by focusing on vulnerable groups such as individuals with lower income and worse health status. In addition, the outreach community health services may need to target individuals aged 66 to increasing efficiency of the services through utilizing results of life-cycle health checkup by the National Health Insurance Corporation.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.179-186
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• 2019

Identifying potential accidents at construction sites is a major concern for the construction industry, and, according to the Korea Occupational Safety and Health Agency, the death rate of safety accidents caused by construction equipment is particularly high at 19.8% as of 2016. Although Internet of Things (IoT) has not been applied widely in construction sites, it can build an operating system that feeds accurate and useful information to construction accident management for identifying potential accidents. In this context, this study proposes an IoT- and RTLS-based construction equipment safety accident prevention system, which can be useful for preventing and managing safety accidents caused by construction equipment. Future deployment of such system would contribute not only to the safety of workers but also to efficient equipment and manpower operation.

• Korean Journal of Environment and Ecology
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• v.10 no.1
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• pp.66-75
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• 1996

To propose basic information for national resource management and planting disign, plant community structure of evergreen broad-leaved forest was investigated. Fifty-two plots(each size 300m$^{2}$) were set up at Ch'omch'alsan area of Chindo, Korea. TWINSPAN and DCA methods were used for classification and ordination analysis. Fifty-two plots were divided into seven groups, which were Quercus variabilis-Carpinus tschonoskii community, Q. glauca community, Castanepsis cuspidata var. sieboldii-Q. stenophylla community, Castanopsis cuspidata var. sieboldii-Camelia japonica community, Q. acuta-Camelia japonica community, Carpinus coreaca-Q spp. community, C. coreana community. Pinus densiflora almost have been selected. Carpinus tschomoskii, Q. variabillis and Q. serrata were to be succeeded by Castanea cuspidata var. sieboldii, Q. stenophylla, Q. acuta and Neolitsea sericea in canopy layer. And Neolitsea sericea, Q. glauca and Camellia japonica was showed high importance values in fertile soil condition. Future restoration plan was necessary for a tourist resort or national forest in warm temperate region. And evergreen broad-leaved plants shall be planted in considering of environmental condition at warm temperate and industrial complex area.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.3
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• pp.63-71
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• 2003

This study investigated about the seasonal variation of pollutant loads flowing into the Yeong-il bay from constructing Tank model which is the simulation model to evaluate the daily river discharge and pollutant load in the Hyeong-san river watershed. The estimated annual average river discharge of Hyeong-san river flowing into Yeong-il bay is about 878.34×10/sup 6/㎥/year which is about 73% of annual average of total precipitation in Hyeong-san river watershed. The annual average of pollutant load flowing into Yeong-il bay was estimated each 15.11 ton-COD/year, 23.24 ton-SS/year, 10.65 ton-TN/year, and 0.54 ton-Tp/year. For the seasonal variation of pollutant loads, it was tended as increasing of river discharge as increasing of inflow pollutant loads at June and July of summer and October of autumn. The main source of pollutant loads was found to be the Pohang city and Pohang industrial complex which are located near the mouth of Hyeong-san river. Therefore, for effective water quality management of Yeong-il bay, the counterplan to reduce pollutant loads from the main source of pollutant loads is required.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.3
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• pp.208-216
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• 2009

This study was performed to investigate levels of POPs in soil by land use and identify congener profiles of PCBs, PCDD/Fs in soil in Korea. Heptachlor, Aldrin, Endrin, Mirex, Toxaphene were not found in all areas. The concentrations of Diedrin, Chlordane, ${\Sigma}$DDT, HCB in soil samples were in ranged from N.D. to 12.08 ${\mu}g$/kg, from N.D. to 16.08 ${\mu}g$/kg, from N.D. to 38.19 ${\mu}g$/kg and from N.D. to 1.32 ${\mu}g$/kg. In case of PCBs, concentration were in ranged from N.D. to 172.12 ${\mu}g$/kg, and PCBs contaminated area was higher than other areas. The concentrations of PCDD/Fs were in ranged from 0 to 6.68 pg I-TEQ/g. In addition, the ${\Sigma}$PCDFs concentration in the industry area soil was higher than ${\Sigma}$PCDDs.

• Journal of Korean Society on Water Environment
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• v.27 no.2
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• pp.167-177
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• 2011

Billions of barrels of briny produced water are generated in the United States every year during oil and gas production. The first step toward recovering or reusing this water is to remove the hazardous organics dissolved in the briny produced water. Biological degradation of hazardous volatile compound could be possible regardless of salinity if they were extracted from briny water. In the current work, the effectiveness of a vapor phase biofilter to degrade the gas-phase contaminants (benzene, toluene, ethylbenzene and xylenes, BTEX) extracted from briny produced water was evaluated. The performance of biofilter system responded well to short periods when the BTEX feed to the biofilter was discontinued. To challenge the system further, the biofilter was subjected to periodic spikes in inlet BTEX concentration as would be expected when it is coupled to a Surfactant-Modified Zeolite (SMZ) bed. Results of these experiments indicate that although the BTEX removal efficiency declined under these conditions, it stabilized at 75% overall removal even when the biofilter was provided with BTEX-contaminated air only 8 hours out of every 24 hours. Benzene removal was found to be the most sensitive to time varying loading conditions. A passive, granular activated carbon bed was effective at attenuating and normalizing the peak BTEX loadings during SMZ regeneration over a range of VOC loads. Field testing of a SMZ bed coupled with an activated carbon buffering/biofilter column verified that this system could be used to remove and ultimately biodegrade the dissolved BTEX constituents in briny produced water.

• Journal of the Korean GEO-environmental Society
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• v.12 no.11
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• pp.39-49
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• 2011

In this paper it was focused on the characteristics of displacement and stress due to the construction of diagonal twin tunnel. In this research, the characteristics have been analyzed with the presumption that the tunnel's diameter (D) is 13m and the ground was formed by weathered rock. In analysis, the width of pillar is 2.0D, 2.5D, 3.0D, the height of soil cover is 3D, 4D, 5D, and the installation angle of diagonal twin tunnel has been changed into $15^{\circ}$, $30^{\circ}$, $45^{\circ}$. And the program used in this analysis is FLAC which is widely used in solution problems of ground engineering in order to gain and analyze occurring shotcrete and rockbolt stress and nearby ground displacement according to pillar width, the height of soil cover and installation angle of diagonal twin tunnel. As a result, in the weathered rock grounds, when the width of pillar is more than 2.0D, the height of soil cover is over 5.0D, and the installation angle of diagonal twin tunnel is lower, they lessen effects on the ground and favorable on the stability of tunnel.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.5
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• pp.692-699
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• 2022

The fishing village new-deal 300 project covers 300 fishing villages and ports for integrated development including reforming backward facilities and utilizing regionally indigenous resources for specialized programs. An analysis was conducted to decide selection factors in the fishing village new-deal 300 project through the expert interview based on AHP(Analytic Hierarchy Process). The results of high-class appraisal items showed that the weights were ranked in the order of the development conditions and basic plan, project effects, project plan, and project execution and management. The project effect obtained 15.57 point in the AHP analysis, whereas the guideline stipulated the point as 6 point for the project effect item, The derived weights for each appraisal item in this study will hereafter be referred in determining the assessment points for the fishing village and port development projects.