• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.51-64
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• 2019

Mt. Geumgang has been a scenic spot representing the Korean peninsula since the Joseon Dynasty, and became a symbol of inter-Korean exchanges with the Gaesong Industrial Complex after the division of the South and North. Mt. Geumgang Tour Course is divided into the Inner-Geumgang (Naegeumgang) and the Outer-Geumgang (Oegeumgang). It was common for the Mt. Geumgang tour route during the Joseon Dynasty and the Japanese Imperialization period to enter the Inner-Geumgang, near Seoul, and come to the East Sea through the Outer-Geumgang. However, the tour route starting from Goseong was utilized for the Mt. Geumgang tour course operated by Hyundai. Because North Korea opened only the Outer-Geumgang area. North Korea has only opened some of its tour courses to Hyundai, but if Geumgang tourism is resumed in the future, there is a high possibility that it will be opened further, such as opening some sections of the Inner-Geumgang in 2007. In this case, it is necessary to connect additional transportation networks to access Inner-Geumgang from South Korea. The best alternative was the restoration of the Mt. Geumgang Railway. However, considering the fact that the reconstruction of the Mt. Geumgang Railway can not be completed due to the construction of the Imnam Dam, it is the most realistic alternative to restore Route 31 connecting Yanggu and Geumgang-eup. As a result of the analysis of road connecting Inner-Geumgang, three routes were confirmed. All of which were adjacent to the existing National Route 31. These routes passing through Dutayeon and Mundeung-ri and joining the Route 31 from Inje. Considering road length, topography characteristics, and military facility layout, it seems that the connection of 'Dutaeyun - Mundeung - Geumgang' is a realistic alternative connecting from South Korea to Inner-Geumgang.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.1
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• pp.73-82
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• 2021

Objectives: This study aimed to investigate the public cognition and information acquisition route for heavy metals and organic solvents in the general population in order to provide information for the development of public relations materials. Methods: The study was carried out by questionnaire from January to March 2011 by an interview with trained surveyors. There were 700 participants, divided by gender and age. A questionnaire was issued consisting of subjective and objective cognition evaluation items and questions about information acquisition route and preferred information acquisition route for six heavy metals and five organic solvents. Data were expressed as a percentage using the SPSS 23.0 software package. Result: For heavy metals, subjective and objective cognition degrees were higher in the order of lead, mercury, cadmium, and arsenic. They were higher among males than females, and in adults compared to school-age subjects. For organic solvents, both cognition degrees were high in the order of acetone, benzene, and formaldehyde. However, cognition degree by gender and age showed a complex pattern. As a response to information acquisition route, broadcast media had the highest in all ages and genders, followed by word of mouth from neighbors in elementary school children, school education or expert lectures in middle and high school students up to people in their 30s, and print media among those in their 40s to over 60s. There was no difference in the order by gender. As a response to preference for information acquisition route, broadcast media also proved the highest in all ages and genders, followed by school education or professional lectures among those in elementary school and over their 60s, and the internet in other age groups. Females preferred school education or expert lectures and word of mouth from neighbors, while males preferred the internet. In the case of the internet, the ranking was higher for preferred information acquisition route compared with the ranking for information acquisition route. Conclusions: This data on cognition degree, information acquisition route, and preferred information acquisition route according to gender and age can provide basic data for the development of educational and promotional materials for heavy metals and organic solvents exposure management.

• Journal of Korea Port Economic Association
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• v.38 no.4
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• pp.199-214
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• 2022

A relative important analysis was conducted to determine what factors are required for port selection in Mokpo New Port and what needs to be addressed first in order to expand automobile and steel cargo handling. The port selection factors of Mokpo New Port were classified into 4 major and 13 intermediate categories, and AHP analysis was used. As a result, items such as 'port facilities', 'accessibility to international ports', 'port facility usage fees', and 'connectivity with neighboring cities/ports' were evaluated as important. The respondent groups were divided into shipowner and shipper, port operator and stevedore, and public official, and an analysis of variance (ANOVA) was conducted to verify if there was a difference in perception between the groups. As a result, shipowner and shipper, port operator and stevedore were similar, but there was a difference from public official group. Shipowner and shipper, port operator and stevedore with similar response characteristics were classified into the 'port practitioner' group, and public official were classified into the 'port policy maker' group, and the difference in perception between the group was tested. Therefore, there were differences in some major category items, and even in the intermediate category items such as 'possession of adjacent hinterland industrial complex', 'cargo equipment', '24-hour port operation', 'inland transportation cost', 'accessibility to international ports', 'marketing and incentives' with statistical. In other words, the 'port practitioner' group evaluated items that can increase cargo creation and handling productivity as important whereas the 'port policy maker' group considers port development and policies such as port infrastructure, connectivity with other ports, and incentive support items are more important.

• Journal of the Korea Society for Simulation
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• v.32 no.3
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• pp.55-66
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• 2023

In recent years, naval vessels have been developed to fulfill a variety of missions by being equipped with various cutting-edge equipment and ICT technologies. One of the main missions of Korean naval vessels is anti-ballistic missile warfare to defend key units and areas against the growing threat of ballistic missiles. Because the process of detection and interception is too complex and the cost of failure is much high, a lot of preparation is required to effectively conduct anti-ballistic missile warfare. This paper describes the development of a simulation model of anti-ballistic missile warfare with combat systems and equipment to be installed on future naval vessels. In particular, the DEVS formalism providing a modular and hierarchical modeling manner was applied to the simulation model, which can be utilized to efficiently represent various anti-ballistic missile warfare situations. In the simulation results presented, experiments were conducted to analyze the effectiveness of the model for effective detection resource management in anti-ballistic missile warfare. This study is expected to be utilized as a variety of analysis tools necessary to determine the optimal deployment and configuration of combat resources and operational tactics required for effective anti-ballistic missile warfare of ships in the future.

• Journal of Korea Foundry Society
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• v.43 no.6
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• pp.302-309
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• 2023

In general, castings often have complex shapes and significant variations in thickness within a single product, making grid generation for simulations challenging. Casting flows involve multiphase flows, requiring the tracking of the boundary between air and molten metal. Additionally, considerable time is spent calculating pressure fields due to density differences in a numerical analysis. For these reasons, the Cartesian grid system has traditionally been used in mold filling simulations. However, orthogonal grids fail to represent shapes accurately, leading to a momentum loss caused by the stair-like grid patterns on curved and sloped surfaces. This can alter the flow of molten metals and result in incorrect casting process designs. To address this issue, simulations in the Cartesian grid system involve creating a large number of grids to represent shapes more accurately. Alternatively, the Cut Cell method can be applied to address the problems arising from the Cartesian grid system. In this study, analysis results based on the number of grid in the Cartesian grid system for a casting flow analysis were compared with results obtained using the Cut Cell method. Casting flow simulations of actual products during various casting processes were also conducted, and these results were analyzed with and without applying the Cut Cell method.

• Clean Technology
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• v.7 no.4
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• pp.251-263
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• 2001

This study was conducted to provide a basic information for recovery plan of Seung-Gi Stream which is a major stream of Incheon metropolitan area. Source and characteristics of pollutants were analyzed and studied. Samples were taken 10 rounds in 5 sections in Seung-Gi stream. Annual pollutants loads and sectional characteristics of pollutants loads were investigated regarding flow rate, pH, DO, SS, $BOD_5$, $COD_{Cr}$, T-P, TKN and concentrations of Zn, Cd, Cu, Cr atoms which enter into Seung-Gi stream during rainy and dry season respectively. As one came close to the Nam-Dong Industrial Complex, sectional discharge loads were heavy and water quality was failed to meet the standard by "Environmental Standard of River Quality". As a result, heavy load of pollutants in Seung-Gi stream was considered to influence negatively the sea water quality of Incheon. Solution plans to solve problems are as follows. First, circulation of treated water at Seung-Gi WWTP(Wastewater Treatment Plant) and retreated water by URC(ultra rapid coagulation) process treat with that. Second, sewage and wastewater is gathered, make it disposed. After then, we circulate treated water. If solution plans be applied, we can predict water quality. Then we could grope for how make to recovery role of Seung-Gi stream as stream.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.363-377
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• 2016

This study was investigated the pollutant load, contamination properties, pollution condition of the fine parts of tributary, the influence of Nakdong river watershed and etc. in the tributaries. The contaminated tributaries were that among the Kumho and Nam river or were too far from site of water quality monitoring stations, regularly. As a result, the water quality level was almost similar between Nam and Kumho River, except for certain parameter including TN(Total Nitrogen), Chl-a(Chlorophyll-a) and SS(Suspended Solid) in which Kumho river were 20~120%. The point discharge load(kg/day) and load density ($kg/day/km^2$) of tributaries were different the pollution level according to the flow-rate ($m^3/sec$) and stream influence area($km^2$), and the difference of these was observed highly at Nam river. Specific contamination investigation of tributaries in Nam and Kumho river watershed was conducted from two to nine points of the fine parts of tributaries depending on the confluence sites and shapes. This result observed high at the Dalseocheon and Uriyeongcheon, respectively. Beside, the pollutant load contribution rate of Nakdong watershed was high about 10% at the Dalseocheon and Uiryeongcheon. This was due to the differences of the environments about the industrial complex, metropolis residence property, agricultural cultivation, livestock pen and the downstream of non-point source.

• Journal of Environmental Science International
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• v.17 no.4
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• pp.423-437
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• 2008

Until comparatively lately, the annual time series of the $SO_2$ concentration had been shown in a decreasing trend in Ulsan as well as other Korean cities. However, the high concentration of $SO_2$ was frequently found in the specific countermeasure region including the national industrial complex such as Mipo and Onsan in the Ulsan city for the period of $2001{\sim}2004$. There are many conditions that can influence the high concentration of $SO_2$ at monitoring sites in Ulsan, such as: First, annual usage of the fuel including sulfur increased in comparison with the year before in spite of the fuel conversion policy which wants to use low sulfur oil less than 3% and LNG. Second, point source, such as the power plants and the petroleum and chemistry stacks, was the biggest contributor in $SO_2$ emission, as a analyzed result of both the air quality modeling and the stack tole-monitoring system (TMS) data. And third, the air pollutants that occurred in processes of homing and manufacturing of the fuel including sulfur were transported slow into a special monitoring site by accumulating along the frontal area of see-breeze. It was concluded that Ulsan's current environmental policy together with control methods should be changed into the regulation on total amount of emission, including a market-based emission trading with calculating of atmospheric environmental critical loads, for the $SO_2$ reduction like the specific countermeasure for the $O_3$ and PM10 reduction in the Seoul metropolitan area. And this change should be started in the big point sources of $1{\sim}3$ species because they are big contributors of Ulsan's $SO_2$ pollution. Especially it is necessary to revitalize of the self-regulation environmental management. Other control methods for sustaining the $SO_2$ reduction are as follows: maintenance of the fuel conversion policy, reinforcement of the regional stationary source emission standard, and enlargement of the stack TMS.

• 대한공업교육학회지
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• v.35 no.2
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• pp.25-42
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• 2010

This research aims to understand how students of technical high schools view 'engineering' as well as to identify the main elements that contribute to the perception on 'engineering.' The research targets are 695 senior students of technical high schools nationwide. The researcher developed the measuring tool for the experiment by referencing the adjective value criteria utilized in the semantic difference method developed by Osgood (1957). There were a grand total of 30 criteria following the preliminary studies. The results of the research are as follows. Firstly, the average value of the overall perception of technical high school students on 'engineering' is 4.27 points. This value just exceeds the standard (4 points). Secondly, when examining the general tendency it can be noticed that there is a sense of stigma that although 'engineering' is significant and valuable it is a field that is overly difficult, complex and even dangerous. Thirdly, 6 main elements that influence the perception on 'engineering' were extracted as results of the factor analysis. The first element is practicality; the second element is emotions; the third element is aesthetics; the fourth is simplicity; the fifth is responsibility; and finally the sixth element is assertiveness. Fourthly, when comparing the average values of the perception on 'engineering' by region, it was seen that there existed a difference on the perception towards 'engineering' based on differing regions.

• Korean Journal of Environmental Biology
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• v.22
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• pp.71-77
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• 2004

Alkylphenols (8), chlorophenols (2), bisphenol A, eoprostanols (2) and cholesterol compounds were analyzed in the surface water and surface sediment taken from Gwangyang Bay and surrounding streams in 2001. Among the target analytes, nonylphenol and dihydrocholesteyol compounds were detected with high concentration and high frequency. t-Octylphenol, bisphenol A and coprostanols were detected only in some sediment samples from the stream. The highest concentration of nonylphenol was determined in stream sample, and concentrations of nonylphenol in the inner part of Gwangyang Bay were higher than those in the out part. Nonylphenol concentrations in the surface seawater and surface sediment samples ranged from 4.0 to 74.0 ng l$\^$-1/ and from 3.1 to 74.3 ng g$\^$-1/ dry wt., respectively. Partition coefficient (LogK$\_$oc/) of nonylphenol between sediment and water was 4.8. Nonylphenol nnd dihydrocholesteol concentrations in the stream surface sediment samples ranged from 4.6 to 808.6 and from 78.4 to 1133.6 ng g$\^$-1/ dry wt., respectively. Relatively high concentrations of nonylphenol were found in the stream samples which aye flowing through industrial complex area, while dihydrocholesterol concentration was relatively high in the stream samples which are flowing through only municipal area. Seaward decreasing tyend in nonylphenol concentration was observed from the Seomjin River estuary to the Gwanyang Bay. Such trend was best supported by the strong correlation between nonylphenol concentration and salinity in water samples.