• Journal of Advanced Marine Engineering and Technology
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• v.35 no.7
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• pp.946-956
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• 2011

The main objectives of this study are to analyze the leaked gas dispersion and quantify the potential overpressures due to vapor cloud explosions in order to identify the most significant contributors to risk by using Computational Fluid Dynamics (CFX & FLACS) for gas fuelled ships. A series of CFD simulations and analyses have been performed for the various gas release scenarios in a closed module, covering different release rates and ventilating methods. This study is specially focused on the LNG FGS (Fuel Gas Supply) system recently developed for the propulsion of VLCC crude oil carriers by shipyards. Most of work presented is discussed on the gas dispersion from leaks in the FGS room, and shows some blast prediction validation examples.

• Journal of Broadcast Engineering
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• v.20 no.2
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• pp.248-256
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• 2015

In this paper, we model the interference plus noise signal for terrestrial cloud transmission systems and present bit error rate (BER) performances. Since terrestrial cloud transmission systems experience co-channel interference from one or more transmitters, they have to operate under a negative signal-to-interference plus noise ratio (SINR) region. The interference plus noise signal can be modeled as Gaussian random variable under the required SINR region and we observe the BER performance of the cloud transmission system using the derived model. Also, we propose an improved channel estimation scheme by averaging the channel estimates based on least square based interpolation scheme. Simulation results show that the cloud transmission system can operate under negative SINR region using the proposed channel estimation scheme.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.893-901
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• 2023

The International Association Marine Aids to Navigation and Lighthouse Authorities (IALA) proposed guidelines for VTS manual operation in 2016 for safe and efficient operation of ship. The Korea Coast Guard (KCG) established and operated 19 VTS centers in ports and coastal waters across the country by 2022 based on the IALA VTS manual and VTS operator's education and training guidelines. In addition, IALA proposed the Inter-VTS Exchange Format (IVEF) Service recommendation (V-145), a standard for data exchange between VTS, in 2011 for efficient e-Navigation system services and safe and efficient VTS service support by VTS authorities. The IVEF service in a common framework for ship information exchange, and it presents seven basic IVEF service (BISs) models. VTS service providers can provide safer and more efficient VTS services by sharing VTS information on joint area using IVEF standards. Based on the BIS data, interaction, and interfacing models, this paper introduced the development of the cloud-based VTS integration services performed by the KCG and the results of the VTS integration platform test-bed for IVEF service implementation. In addition, the results of establishing a cloud VTS integrated platform test-bed for the implementation of IVEF service and implementing the main functions of IVEF service were presented.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.11a
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• pp.298-299
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• 2022

Digital Transformation in the maritime transportation sector means "by utilizing digital technologies such as artificial intelligence, big data, Internet of Things, block chain, and cloud to create new business models, products, and services for maritime transportation-related companies. It can be defined as a continuous process that adapts to or drives disruptive changes in the market" (Chang, 2021). In a situation where various digital conversion technologies are applied and started to be used in the domestic port logistics field, active acceptance by members can bring about the success of digital conversion. Therefore, in this study, in order to investigate the acceptability of digital transformation in the domestic port logistics sector,

• Journal of the Korean Society of Costume
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• v.22
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• pp.97-118
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• 1994

This stud is my second trial to examine the costume of Balhae Dyansty. The subject of this study is the costume of a bronze statue excavated in the Maritime Provinces of Russia. The bronze statue is in the custody of Vladivostok Museum E.V. Shavkunov a Russian archelogist reported it a statue of-ficial of balhae dynasty in the 7-8th century. Judged his report lack of basis I suggest new opinion on sex, age, married or unmarried. social position manufactured time of the statue by comparative study on the costume hair-style and appearance of the statue with around nations' antiquities. hair-style of the statue is basically included in Ssangge and complexed style of Sage Ssangsuhuange, and Guange, Generally, Ssangge is a hair style of children, unmarried women, court ladies, dancing girls, and instrument player (lady)s'. The statue wears round-necked blouse long skirt broad fabric belt at high waist broad sleeve and confront collar coat cloud shaped shawl and risen tip shoes. The figure of statue is de-scribed plump. The statue shows straight sil-houette and high waist typical style of Tang, Uddai, The most characteristic facto is cloud shaped shawl Cloud shaped shawl was originally one of the northern race's shoulder ornaments. From the view of Comparative study the antiquities of NamDang and JunChock are simi-lar to this statue. Besides Tsukanovka river where the statue was excavated is Kraskino ruins of a castle formed single cultural layer of Balhae Dynasty and are relics of the layer of Balhae Dynasty and are relics of the latter period of Balhae Dynasty. Therefore this statue is assumed to have been manufactured at the last years of Balhae Dynasty and to be a figure of unmarried woman not official.

• Journal of Navigation and Port Research
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• v.46 no.5
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• pp.458-470
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• 2022

As the 4th industrial revolution progresses, the application of several cutting-edge technologies such as the Internet of Things, big data, and mixed reality (MR) in relation to autonomous ships is being considered in the maritime logistics field. The aim of this study was to apply the concept of a digital twin model based on Human Machine Interaction (HMI) including a digital twin model and the role of an operator to a ship. The role of the digital twin is divided into information provision, support, decision, and implementation. The role of the operator is divided into operation, decision-making, supervision, and standby. The system constituting the ship was investigated. The digital twin system that could be applied to the ship was also investigated. The cloud-based digital twin system architecture that could apply investigated applications was divided into ship data collection (part 1), cloud system (part 2), analysis system/ application (part 3), and MR/mobile system (part 4). A Mixed Reality device HoloLens was used as an HMI equipment to perform a simulation test of a digital twin system of an 8 m battery-based electric propulsion ship.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.13 no.1
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• pp.17-25
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• 1977

For four calender years (1971-1974), daily observations of weather conditions (air temperature, humidity, wind speed, wind direction, cloud amount, fog, precipitation etc.) at six stations in the north western Pacific Ocean are used to calculate mean monthly values and to check extra-conditions. At Petropavlosk and Miko'skoe, where indicate the characteristics of modified continental climate, the temperature and humidity are high in summer, and Iow in winter. At A Dak and She Mya, where indicate the characteristics of warm current type maritime climate, humidity is high in all season and annual range of air temperature is nearly negligible. At Simusir and Vasi!' eva, where indicate the characteristics of cold current type maritime climate, humidity is high in all season and annual range of air temperature is $15^{\circ}C.$ As dry cooling power is relatively high in winter, working condition on deck is bad. Most of fogs are advection fog in the area of cold current type climate in summer.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.6
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• pp.433-440
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• 2023

This study aims to establish safety zones for bunkering operations of hydrogen propulsion ships in coastal areas through risk assessment and evaluate their validity. Using a 350 kW-class ferry operating in Busan Port as the subject of analysis, with quantitative risk assessment based on accident consequence and frequency analysis, along with a social risk assessment considering population density. The results of the risk assessment indicate that all scenarios were within acceptable risk criteria and ALARP region. The most critical accident scenarios involve complete hose rupture during bunkering, resulting in jet flames (Frequency: 2.76E-06, Fatalities: 9.81) and vapor cloud explosions (Frequency: 1.33E-08, Fatalities: 14.24). For the recommended safety zone criteria in the 6% hose cross-sectional area leakage scenario, It could be appropriate criteria considering overall risk level and safety zones criteria for hydrogen vehicle refueling stations. This research contributes to establishing safety zone for bunkering operations of hydrogen propulsion ships through risk assessment and provides valuable technical guidelines.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.609-619
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• 2023

This study aimed to investigate the formation of the social perception of domestic maritime sports using text mining analysis of keywords and topics from domestic media coverage over the past 10 years related to representative maritime sports, including yachting, rowing, and canoeing. The results are as follows: First, term frequency (TF) and word cloud analyses identified the top keywords: "maritime," "competition," "experience," "tourism," "world," "yachting," "canoeing," "leisure," and "participation." Second, semantic network analysis revealed that yachting was correlated with terms like "maritime," "industry," "competition," "leisure," "tourism," "boat," "facilities," and "business"; rowing with terms like "competition" and "Chungju"; and canoeing with terms like "maritime," "competition," "experience," "leisure," and "tourism." Third, topic modeling analysis indicated that yachting, rowing, and canoeing are perceived as elite sports and maritime leisure sports. However, the perception of these sports has been demonstrated to have little impact on society, public opinion, and social transformation. In summary, when considering these results comprehensively, it can be concluded that yachting and canoeing have gradually shifted from being perceived as elite sports to essential elements of the maritime leisure industry. Contrariwise, rowing remains primarily associated with elite sports, and its popularization as a maritime leisure sport appears limited at this time.

• Journal of the Korea Society of Computer and Information
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• v.22 no.2
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• pp.133-139
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• 2017

Today, the activities of individuals and corporations are dependent not only on digital technology but also on the future of society, which is referred to as the fourth industrial revolution. Since the traces that arise from the crimes that occur in the digital society are also inevitably developed into a society that should be found in the digital, the judicial dependence of judging by the digital evidence is inevitably increased in the criminal procedure. On the other hand, considering the fact that many users are using virtual shared computing resources of service providers considering the fact that they are being converted into a cloud computing environment system, searching for evidence in cloud computing resources is not related to crime. The possibility of infringing on the basic rights of the criminal procedure is increased, so that the ability of evidence of digital data which can be used in the criminal procedure is limited. Therefore, considering these two aspects of digital evidence, this point should be fully taken into account in judging the evidence ability in the post-seizure warrant issuance and execution stage as well as the pre-emptive control. There is a view that dictionary control is useless, but it needs to be done with lenient control in order to materialize post-modern control through judging ability of evidence. In other words, more efforts are needed than ever before, including legislation to ensure proper criminal procedures in line with the digital age.