• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.59-64
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• 2018

As part of measures to reduce fine dust, the government is promoting a project to convert the fuel of Yard Tractors(YT, tractors operated at ports), from diesel to LNG (Liquefied Natural Gas). While a port having a small number of yard tractors, it is not proper to construct a stationary LNG fueling station and supply LNG to YT due to a problem of BOG (Boil off gas) generation. Therefore, it is necessary to make a regulation and a standard on mobile LNG YT refueling station installation and inspection as an alternative. In this study, we have investigated domestic and foreign mobile LNG refueling cases and refueling standards, including the USA and Europe. In addition, we have suggested the risk reduction method according to the cause after investigation of the cause of LNG accidents. And last, based on the proposed risk reduction measures, we have proposed an amendment to the Regulation of the Urban Gas Business Law in Korea. The proposed mobile LNG YT refueling amendment of the Regulation includes ; maintenance of the safety distance from the protection facility, installation of an interlock device to prevent refueling in places other than the authorized place, installation of the identification system through biometrics, separation of the tank lorry and tow vehicle before refueling, checking the wheel fixed status of tank lorry before refueling, construction of the impounding area, safety measures before, during and after refueling, etc. The safety standards proposed in this study could be used as a reference in establishing standards for mobile LNG vehicle refueling in the near future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.767-774
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• 2017

Maritime traffic safety audits (MTSA) were enacted in order to ensure marine traffic safety throughout changes or the construction of water facilities, port facilities, etc. After the introduction of MTSA, the scope of subject vessels was restricted to an LOA of more than 100 m or a maximum speed of more than 60 knots as of 2014. In this study, the scope of subject vessels was re-examined in comparison with specific marine traffic safety areas and tanker prohibited areas identified in the maritime safety act. Furthermore, the state of subject vessels and exception cases for MTSA were also analyzed. As a result of these analyses, MTSA were deemed necessary for dangerous goods carriers of more than 1,000 G/T in specific marine traffic safety areas and dangerous goods carriers of more than 794 G/T in tanker prohibited areas. Finally, the necessity of further review was suggested given the present scope of subject vessels.

• Journal of Convergence for Information Technology
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• v.9 no.9
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• pp.133-140
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• 2019

Following the recent US trade deficit, the trade war began between Korea and Japan in July. Korea's trade dependence is about 60% or more, indicating high export dependence and import dependence. The purpose of this study is to examine export amount, export volume, export price index, Treasury bond interest rate and analyze how index affects export amount. This study attempts to analyze the comovement and volatility with export amount. For this purpose, monthly data for each indicator were selected for a total of 234 months from January 2000 to June 2019. As a result of analysis, exports amount and exports volume showed very high comovement, exports amount and interest rates showed low comovement, but exports amount and exports prices showed very low comovement. In the future, Korea should continue to increase exports amount in view of its high dependence on trade, along with policies to expand the domestic market. To this end, strategy to increase exports volume should be presented. Korea should increase the logistics environment and competitiveness of each port and airport, improve domestic and overseas network construction and support services of logistics companies.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.43-52
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• 2021

As port development in soft ground is actively promoted for international logistics and transportation, the Deep Mixing Method (DMM) is continuously applied to form an improved column body directly in the ground by mixing cement with soil to secure the stability of the structure. However, in the case of cement, there is a problem of emitting a lot of greenhouse gases during the production process, so the development and use of new alternative materials are socially required to achieve the national goal of carbon neutrality. Accordingly, in this study, CMD-SOIL, developed to induce a hardening reaction similar to cement by recycling recycled resources, was used as a ground improvement material for the DMM. In addition, it was attempted to determine the possibility of replacing cement by conducting on-site test construction and evaluating applicability. As a result of the study, the compressive strength of CMD-SOIL compared to the design reference strength was 1.46 to 2.64 times higher in the field mixing test and 1.2 to 5.03 times higher than in the confirmed boring. In addition, the ratio (λ) of the compressive strength in the field to the design reference strength was 0.63 to 1.14, which was similar to the previous research results. Therefore, in the case of CMD-SOIL, it is possible to express the compressive strength necessary to secure stability, and there is no difference in applicability compared to existing materials such as ordinary portland cement and blast furnace slag cement, so it was analyzed that it could be used as a ground improvement material for the DMM.

• Journal of the Korean Geotechnical Society
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• v.38 no.7
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• pp.25-37
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• 2022

In this paper, a small-scale model testing system was developed using a series of small-scale model tests to analyze the mechanism of compaction pile formation and evaluate the quality of controlled grading aggregates proposed as an alternative material to the sand compaction pile (SCP) method and granular compaction pile (GCP). These are the most typical ground improvement methods in field practice, particularly for soft grounds. However, the SCP has faced difficulties due to the supply shortage of natural sand and the corresponding price surge of sand. The GCP is limited in marine soft grounds because of the failure occurring at the pile tip caused by excessive expansion of the deeper bulbs, leading to uneven bulb formation. The uniformity of compacted pile bulbs is critical to ensuring the bearing capacity and quality of the compaction pile. This study aims to evaluate the performance of the new material and controlled grading aggregates using small-scale model tests simulating field compaction process to investigate its potential application in comparison with SCP. The compaction piles are examined in four cases according to different materials used for compaction pile and clay strength. The compaction pile materials, which are made of sand and controlled grading aggregates, used in this study were compared to reveal the mechanism of the bulb creation. The experimental data confirm that the bulb formation quality of the traditional sand and the new material, controlled grading aggregates are comparable. The compaction pile made of controlled grading aggregates presents higher bearing capacity than that of marine sand.

• Journal of Intelligence and Information Systems
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• v.29 no.3
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• pp.79-101
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• 2023

The current status of local road pavement management in Jeollabuk-do only relies on the accomplishments of the site construction company's pavement repair and is only managed through Microsoft Excel and word documents. Furthermore, the budget is irregular each year. Accordingly, a systematic maintenance plan for local roads is necessary. In this paper, data related to road damage and road environment were collected and processed to derive possible areas which could suffer from road damage. The effectiveness of the methodology was reviewed through the on-site inspection of the area. According to the Ministry of Land, Infrastructure and Transport, in 2018, the number of damages on general national roads were about 47,000. In 2019, it reached around 38,000. Furthermore, the number of lawsuits regarding the road damages were about 93 in 2018 and it increased to 119 in 2019. In the case of national roads, the number of damages decreased compared to 2018 due to pavement repairs. To measure the priorities in maintenance of local roads at Jeollabuk-do, data on maintenance history, local port hole occurrence site, overlapping business section, and emergency maintenance section were transformed into data. Eventually, it led to improvements in maintenance of local roads. Furthermore, spatial data were constructed using various current status data related to roads, and finally the data was processed into a new form that could be utilized in machine learning and predictions. Using the spatial data, areas requiring maintenance on pavement were predicted and the results were used to establish new budgets and policies on road management.

• Journal of the Korea Society for Simulation
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• v.19 no.2
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• pp.29-41
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• 2010

Due to the recent technological advance, new types of AS/RS which can handle containers are being developed, and it is expected that they will be applied to related industries before long. Some companies and institutes in our country have constructed pilot systems for high-density-high-stacking systems and tested them to develop AS/RS-typed warehouses for containers. Along with this kind of construction efforts, development of rules to operate such systems efficiently and safely is also important. When outward-bound shipment is scheduled in container port, re-marshalling which rearranges containers in the yard to make shipment easy is conducted. In this paper, operating rules for the re-marshalling as well as simulation experiments to evaluate the performance of the rules are presented. We suggested two kinds of alternative sets of operating rules for re-marshalling and described the relevant logics corresponding to all possible cases for each alternative of operating rules. Through various simulation experiments, we found that each alternative has the merits and demerits at the same time and we could not say the one is always superior to the other. As a useful strategy, changing the applying operating rule is recommended from moment to moment depending on the expected number of operations at the landside input/output position.

• Journal of Environmental Health Sciences
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• v.49 no.4
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• pp.190-200
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• 2023

Background: Gunsan has been constantly affected by pollutants generated by the Saemangeum development and the construction industry since the completion of the Saemangeum seawall on April 27, 2010. However, there are limitations to its study, such as taking into consideration weather conditions, geographical factors, and foreign inflows. Objectives: In this study, we compared the Existing-CAPSS emissions of Gunsan with Recalculated-CAPSS emissions data to analyze the differences in emissions characteristics by year (2016~2019). Methods: Using Existing data on CAPSS emissions (2016~2019) and Recalculated-CAPSS emissions (2016~2019) for Gunsan, which were Recalculated following the improvement of emissions calculations for 2020, we organized CO, NO_X, SO_X, PM₁₀, VOC_S, and NH₃ emissions by substance and investigated the differences and characteristics of the Recalculated emissions by year. Results: For Re-CO and Re-PM₁₀, the emission characteristics of CO were examined as energy industry combustion and PM₁₀ emission characteristics were examined as ship cargo from non-road transportation sources, as ship leisure sources were excluded from non-road transportation source emissions. Conclusions: Comparing the emissions of Existing-CAPSS and Recalculated-CAPSS in Gunsan, the emissions of Recalculated-CAPSS by substance decreased by 39.76% for CO, 9.98% for PM₁₀, 5.53% for VOC_S, and 9.24% for NH₃, while Re-NO_X increased by 2.86% and Re-SO_X increased by 1.97%. On the other hand, when comparing the emissions characteristics of Existing-CAPSS and Recalculated-CAPSS in Gunsan, Jeonju, and Iksan, the emission characteristics of Re-NO_X, Re-SO_X, Re-VOC_S and Re-NH₃ were similar to those of Ex-NO_X, Ex-SO_X, Ex-VOC_S, and Ex-NH₃. As such, Gunsan, Iksan, and Jeonju, showed differences in the comparison of different emission characteristics due to the geographical characteristics of the region (population, area, topography, weather factors) and the characteristics of the industrial complex (metal, petrochemical).

• Journal of the Daesoon Academy of Sciences
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• v.32
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• pp.109-136
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• 2019

The purpose of this study is to look at the concept of Gaebyeok as used by Kang Jeungsan (姜甑山) from a civilizational perspective. The combination of East Asian civilization during the period of Korea's port-opening and the subsequent inflow of Western powers with material civilization all at the forefront in the late Joseon Korea, served as the driving force for a new civilizational transition. Unlike the Chuk-sa Party and the Gae-hwa Party, modern Korean religions that emphasized Gaebyeok also responded to Western civilization and suggested a new view of civilization. Kang Jeung-san, resisting discrimination and oppression, presented a civilization built upon mutual beneficence while criticizing Western civilizations which centered on reason. Amid this process of the spread of modern Western civilization, Jeungsan declared the construction of a new civilization to the people who were negatively impacted by various social factions, such as class and gender discrimination, political corruption, exploitation via political corruption, and the inflow of Western powers. Jeungsanist Thought developed criticisms of materialism and human alienation, and this resulted in the claim of Gaebyeok. This was an expression of efforts to build a new civilization that aimed to harmonize, integrate, and thrive. The new civilization envisioned by Jeungsan was that of a society run according to mutual beneficence, and it can be summarized as a 'Civilization of Harmonious Union' that integrates philosophical thought and civilizational models of both East and West. This could also be referred to a 'Civilization of Public-commons and Harmony between Divine Beings and Human Beings (神人公共).' The life of Jeungsan was a life spent in the service of curing the world to save the lives of humanity. Since then, his 'movement of mutual beneficence' as observed in Mugeuk-do and Taegeuk-do were also efforts to build the new civilization envisioned by Jeungsan.

• Journal of the Korean Geotechnical Society
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• v.25 no.1
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• pp.77-88
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• 2009

Cone factors, $N_{kt}$, $N_{ke}$ and $N_{{\Delta}u}$, for estimating undrained shear strength of Busan clay are evaluated in this study. For this, CPTu and field vane tests are performed for clay layers at two sites, Busan new-port and Noksan, and also $CK_0U$ triaxial tests with undisturbed samples taken from the same site are carried out. From experimental results, it is observed that the undrained shear strengths of clay increases with depth, and the undrained shear strength obtained from triaxial tests is 1.5 times higher than one obtained from vane tests. The normalized undrained shear strengths of Busan clay from triaxial and vane shear tests are $0.26{\sim}0.44$ and $0.20{\sim}0.23$, respectively. In CPTu results, cone tip resistance ($q_c$) and pore pressure ($u_2$) linearly increase with depth, and the pore pressure ratio ($B_q$) of Busan clay is within the range of $0.3{\sim}1.0$. The cone factors, which are determined by comparing the CPTu results with $CK_0U$ triaxial and vane shear test results, are found to be $5{\sim}20$ and $10{\sim}35$, respectively. It is also observed that the cone factors are inversely proportional to the pore pressure ratio. From this, the prediction methods for evaluating the cone factors of Busan clay are developed.