• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.604-610
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• 2018

Recently, due to the rapid growth of the leisure industry, demand for small-scale flotation and mooring pontoon platforms has been increasing rapidly. Standard rules for the design and structural safety of such structures have become necessary. This paper provides criteria that can be referenced when designing pontoon platforms, and also introduces structural safety evaluation procedures. In this study, the structural safety and stability of a 15-meter pontoon platform were investigated through structural design and finite element analysis. For platforms of less than 10 meters in length, a simple structural calculation can be used, but for platforms over 10 meters, a detailed structural strength review must be considered to meet safety guidelines defined in existing regulations. The structural strength of the initial design was examined and its structural safety was verified. For future research, it is an evaluative system was developed that can be used to examine the various loading conditions during design.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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• pp.307-313
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• 2013

This paper presents a simulation for passenger ship evacuation considering determination of evacuating direction based on walking direction potential function. In order to determine walking direction of a passenger, his/her position in two dimensional plane was adopted as a design variable, and fixed boundaries such as walls and obstacles were adopted as constraints. To solve this optimum problem, a walking direction potential function was adopted as an objective function. This potential function was configured as a kind of penalty function and it contained two components. One is a potential function concerned with the distance to the destination, and other is a potential function based on the effect of walls and obstacles. To determine evacuating direction, this problem was solved by minimizing the walking direction potential function every unit time during the simulation. The crowd behavior of the passenger consisted of the flock behavior, a form of collective behavior of a large number of interacting passengers with a common group. With the proposed algorithm, the test problems in International Maritime Organization, Maritime Safety Committee/Circulation 1238(IMO MSC/Circ.1238) were implemented and the direction of passengers and total evacuation time was analyzed.

• The Journal of Fisheries Business Administration
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• v.31 no.2
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• pp.67-91
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• 2000

Fisheries Agreements among Korea, China, and Japan, for the effective management of fisheries resources and protection of fisheries disputes, have been processed in a manner to conclude interim arrangements those are effective prior to the final demarcation of the maritime delimitation which often requires much time to settle among the relevant states, Based on this understanding, Korea, China, and Japan, had proceeded their mutual fisheries agreement ; and, two fisheries agreements, between Korea-Japan and China-Japan, have already entered into force on 22 January 1999 and on 1 June 2000, respectively. Lastly fisheries negotiation between Korea and China has been concluded in order to make it effective on 30 June 2001. As Korean fisheries have already experienced the impacts after the entry into force of Korea-Japan Fisheries Agreement, it is inevitable that the likewise will also be true for the Korea-china Fisheries Agreement. The results of fisheries negotiation should minimize the loss by ensuring Korean flagged vessels' fishing rights to the maximum level in the counterpart's waters, and to maximize our counterpart's loss by restricting its vessels' fishing rights to the minimum level in our waters. However, such goals are almost unreachable in an intergovernmental negotiation. On this ground, regardless of the results, the negotiation is highly criticized from all the interested realms of the society. First, this study reviews the negotiation process ana subject matters of the fisheries agreement, and then evaluates the disputed items issued by academic, political, and industry areas in an international law and fisheries perspective. After the entry into farce of fisheries agreement, various activities should be accommodated as future tasks, such as the adjustments of the domestic fisheries structure, the reorganization of the resource management based fisheries structure, the construction of EEz large surveillance system, and the construction of the multilateral fisheries cooperation system Through an earlier implementation of those tasks, the Korean fisheries will be better prepared in minimizing the predicted impacts once the Korea-China Fisheries Agreement becomes effective.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.31-39
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• 2007

Recently, the nonlinear dynamic responses among waves, submarine pipeline and seabed have become a target of analyses for marine geotechnical and coastal engineers. Specifically, the velocity field around the submarine pipeline and the wave-induced responses of soil, such as stress and strain inside seabed, have been recognized as dominant factors in discussing the stability of submarine pipeline. The aim of this paper is to investigate nonlinear dynamic responses of soil in seabed, around submarine pipeline, under wave loading. In order to examine wave-induced soil responses, first, the calculation is conducted in the whole domain, including wave field and the seabed, using the VOF-FDM method. Then, velocities and pressures, which are obtained on the boundary between the wave field and the seabed, are used as the boundary condition to compute the wave-induced stress and strain inside seabed, using the poro-elastic FEM model, which is based on the approximation of the Biot's equations. Based on the numerical results, the characteristics of wave-induced soil responses around submarine pipeline are investigated, in detail, inrelation to relative separate distance of the submarine pipeline from seabed. Also, the velocity field around the submarine pipeline is discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.69-70
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• 2017

As the industry develops, the size of buildings and ships are getting bigger and more complicated. In such a complex space, emergency evacuation systems are required because of the possibility of casualties when an accident situation occurs. However, because present systems are composed of basic devices, such as alarms, emergency exit signs, and announcement regarding the situation and inform only the least information to evacuees, evacuees are not able to judge objectively. To solve these problems, various evacuation algorithms have been proposed. However, these studies aim to search evacuation routes based on specific risk factors or to model the effects of bottlenecks in evacuation situations. Therefore, there is a limit to apply to real systems. Therefore, we propose algorithms to search the optimal evacuation route considering various risk factors such as fire and bottleneck in evacuation situations and to be applicable in actual situation in this paper. Performance evaluation using computer simulations showed that the proposed scheme is effective.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.6
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• pp.843-851
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• 2009

Much work has already been done to control and regulate the worldwide problems caused by climate change, particularly the issues on greenhouse gas (GHG) emissions. Carbon dioxide ($CO_2$), having the highest form of concentration among GHGs composed around 1.0 billion tons of emission, and comprises about 98% of the total emissions from the shipping industry. Korean trade mainly rely on the sea transportation. Korean ship tonnages that was brought about by shipbuilders all over the country, continues to grow annually due to the prevailing demands on goods or material supplies and depicting only a small part of the global maritime activity. Nowadays, new build ships coming from the Korean Shipbuilders are being optimized by hull, structure and appendages design, The operational capability of the propulsion and auxiliary machineries in its maximum capacity to achieve the highest possible efficiencies for energy and onboard power use to mitigate $CO_2$ emissions are continually being done through the help of research and development. In this paper, the energy efficiency design index and anboard power capacity of Korean new build ships have been analyzed with response to data collected by ship types, and its respective fuel consumption in relation to $CO_2$ emission results. In response to climate change convention outcome proposals, the best way for the new build ships to become energy efficient is by lowering its operational speed thru adopting the state of the art diesel propulsion engines, patronizing the best sailing practice to lower the transportation cost on the different sea trade routes also helps in $CO_2$ mitigation.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.2
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• pp.333-342
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• 2017

In this study, we studied and analyzed 3,751 ships regarding detention list of Tokyo MOU from 2013 to 2015 total for 36 months. The Member Authorities of the MOU has 20 committee consists of Korea and Peru joined in 2015. 1,250 ships in a year and 140 ships in a month are granted PSC Action Code-30 corresponding to detention. Averagely, 30,943 ships in a year and 2,579 ships have been received PSC inspection. Additionally, according to this PSC inspection, rate of Detention reaches to 4.04%. When it comes to Korean Flag Ships however, the number of Detention ships of Tokyo MOU has been rather increased from 3 ships in 2013 to 18 ships during 2years. Furthermore, MOU in the all over the world, the number of ships had Detention has largely increased from 5 ships to 9 up-to 19ships. The number of Detention Ships has been reached to 44.8% of 1~2 days period of Detentions, under 3~10 days period of Detentions reaches to 34.7% and over 10 days detention reaches 10.3%, which cause economically enormous loss. Continually, each MOU has been implemented Concentrated Inspection Campaign(CIC) annually. Each MOU including Tokyo MOU implemented "Crew Familiarization for Enclosed Space Entry" for 3 month from september, and During this period, Concentrated Inspection were carried out to 8,429 ships of Tokyo MOU. Accordingly, If ships and owners can get the information of CIC and deliver the information to the ship, then Ships can minimize the rate of Detention by thoroughly preparing for PSC Inspection. In addition, Bulk Carrier and General Cargo ship occupy 50% of rate of Detention and it shows that majority of list among Nature of Deficiencies are identical. Finally, If we can obtain the information of the ships inspected previously, We can reduce the number of detention by preparing for PSC inspection. And this will be able to contribute to shipping industry also.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.31-45
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• 2012

This study was conducted to estimate the stability of a quay wall in case of wave overtopping under the combined action of an earthquake and tsunami using limit equilibrium method. The tsunami force was calculated by using a numerical program called TWOPM-3D (3-D one-field Model for immiscible TWO-Phase flows). Especially, the wave force acting behind the quay wall after a tsunami wave overtopping was estimated by treating back fill as a permeable material. The stability of the quay wall was assessed for both the sliding and overturning modes under passive and active conditions. The variation in the stability of the quay wall with time was determined by parametric studies, including those for the tsunami wave height, seismic acceleration coefficient, internal friction angle of the soil, wall friction angle, and pore water pressure ratio. When the earthquake and tsunami were considered simultaneously, the tsunami induced wave overtopping increased the stability of the quay wall under the passive condition, but in the active condition, the safety factors decreased.

• Journal of Ocean Engineering and Technology
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• v.32 no.5
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• pp.310-323
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• 2018

In order to protect lives and prevent large-scale injuries in the event of a fire on a ship or an offshore plant, most classification societies are strengthening their fire resistance designs of relevant cargo holds and accommodation compartments to keep flames from being transferred from a fire point to other compartments. Particularly in critical compartments, where flames should not propagate for a certain period of time, such as the A60 class division, both the airtightness and fire-resistant design of a piece passing through a bulkhead are subject to the Safety of Life at Sea Convention (SOLAS) issued by the International Maritime Organization (IMO). In order to verify the suitability of a fire-resistant design for such a penetrating piece, the fire test procedure prescribed by the Maritime Safety Committee (MSC) must be carried out. However, a numerical simulation should first be conducted to minimize the time and cost of the fire resistance test. In this study, transient thermal analyses based on the finite element method were applied to investigate the heat transfer characteristics of a bulkhead penetration piece for the A60 class compartment. In order to determine a rational bulkhead penetration piece design, the transient heat transfer characteristics according to the variation of design parameters such as the diameter, length, and material were reviewed. The verification of the design specification based on a numerical analysis of the transient heat transfer performed in this study will be discussed in the following research paper for the actual fire protection test of the A60 class bulkhead penetration piece.

• Journal of Navigation and Port Research
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• v.31 no.10
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• pp.897-903
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• 2007

The purpose of this study is to examine empirically the cultural problem and working attitude in the Korean vessel of combined foreign crews, Currently, the restrictions on the employment of the foreign crews are being eased in the Korean shipping industry and many problems such as misunderstanding and dissonance in working have been occurred consequently, However, specific and empirical studies regarding different culture between Korean and foreign crews working together in the vessel have not yet carried out, So this study is meaningful as exploratory research about cultural homogeneity, onboard working tolerance and organization commitment for combined foreign crews and the result of this study contributes to management of crew and vessel organization.