• Journal of the Society of Naval Architects of Korea
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• v.53 no.1
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• pp.10-17
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• 2016

When a planing hull straightly runs and turns, its floating position and pitch angle are changed depending on its speed, and large transient motion happens. In this paper, six degrees of freedom(6 DOF) equations of motion, which could simulate the motion of a planing hull, are established. Static and dynamic forces in vertical plane are modeled using pre-calculated displacements and metacentric heights depending on various draft, lift under bottom, and vertical damping coefficients which are used to tune the final motion. Hydrodynamic coefficients in horizontal plane at various equilibrium state are calculated by using Lewandowski's empirical formula and the speed-dependent equilibrium state are calculated beforehand by Savitsky's formula. The speed effects are considered by curve-fitting the coefficients at various speed to the polynomials. Accelerating, decelerating and backing, turning, and zig-zag are simulated and compared with the sea trial results, and it is confirmed that the speed reduction, roll, and pitch during such maneuvers of sea trial and simulation are well consistent.

• Journal of Fisheries and Marine Sciences Education
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• v.3 no.1
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• pp.35-43
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• 1991

The fishing vessels operation is a kind of maritime profit-making activities, which are complicatedly integrated by the basic and supplemental fishing activities with navigation. The Fishing Vessels Act of Korea defines the character of fishing vessels and gives a legal status to them, and this Act itself is linked with the allied public laws including the Ships Act of Korea. For this reason, the legal status of fishing vessels as Korean flagged ships by the public law is analogous to the general commercial vessels. And the specific character of ownership of the fishing vessels by the Korean Maritime-Commercial Act as a privated law is analogous to the general commercial vessels, nevertheless the Chapter 4(Carriage of goods) and the Chapter 5(General average) of this Act do not apply to the fishing vessels except the fish carriers. A fishing vessel possesses the legal status as a Korean flagged ship by having it registered and putting it on record under the provision of national law, however the principle of genuine link is an important factor for acquisition of nationality. Especially, the basic rules by the Law of the Sea those are attended with the distant-water fishing vessels operation at the overseas fishing ground are summarized as follows ; Firstly, the rights of navigation and fishing activities on the high seas are fundamentally recognized to all states, but the freedom is restricted according to the international legal order aiming at protection of reasonable interests of other states and conservation of the living resources and marine environment. Secondly, in the EEZ or EFZ the freedom of navigation is recognized, but fishing activities are exclusively ruled by the national law of the coastal state. Thirdly, foreign fishing activities are prohibited but the right of innocent passage is recognized in the territorial sea, while both activities are prohibited in the internal waters of the coastal state.

• Strategy21
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• s.40
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• pp.115-130
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• 2016

The security environment surrounding the East Asian seas is rapidly changing due to the naval arms race among coastal states. The arms race is likely to worsen the security dilemma of the countries involved, thus increasing the chances for armed conflicts. It is too early to tell how the contemporary naval arms race in the region will evolve. But, for sure, the level of uncertainty is increasingly becoming high and intense. At the same time, there is emerging a legal warfare or lawfare among the rival countries. In particular, the United States and China have been involved in a serious debate about the nature and scope of the right of innocent passage and freedom of navigation in other countries' maritime zones. In collaboration with its regional allies, the United States has also put normative pressures on China with its excessive claims in the South China Sea. The latest arbitral tribunal case between the Philippines and China illustrates the point. With both arms race and normative competition in play, the future of East Asian maritime security will remain very complex and uncertain.

• Journal of Fisheries and Marine Sciences Education
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• v.11 no.2
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• pp.150-183
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• 1999

Korea-Japan Fisheries Agreement concluded in 1965 made a contribution to the stable development of fisheries relationship for both countries until the year of 1980. From the time on thereafter a series of respectable fishery disputes occurred throughout the period of fisheries self-regulation in accordance with alteration of home and abroad conditions. And both countries marched into a cooperation era by enforcement of the new fisheries agreement from the 23 January 1999, because the Fisheries Agreement system of 1965 had many limitations to settle the fundamental fisheries problems. In this paper, the author carried out the legal interpretation, arrangement of historical facts and evaluation of actual results of the Korea-Japan Fisheries Agreement of 1965. The key contents of the Fisheries Agreement were the establishment of 12-nautical mile exclusive fishery zone and the joint-control fishery zone under the principles of maintenance of MSY for fishery resources, freedom of high seas and mutual cooperation. The legal foundation of the conclusion of the Fisheries Agreement were the San Francisco Peace Treaty of 1952 and the four International Conventions on the Law of the Sea of 1958. During the 33 years, the fisheries power of Korea made a rapid stride, on the other hand that of Japan was almost stagnated. And in the meantime, there were very important development on the international law of the sea, for instant, the settlement of 12-nautical mile territorial sea regime and the establishment of 200-nautical mile exclusive economic zone regime. Annual meetings of the Joint Fisheries Committee were not successful to fill the role for conservation of fishery resources. The Fisheries Self-Regulation Agreement concluded in 1980 was also insufficient to accept the new international regime on the law of the sea, for that reason it was terminated on 23 January 1999. But it is true that the Fisheries Agreement of 1965 made a contribution to normalization of fisheries relationship between both countries and fisheries development of Korea.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1998.10b
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• pp.27-36
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• 1998

This paper presents a brief outline of dynamic stability of damaged ship in rough, beam wind and waves. The one degree-of-freedom, linear roll equation is adopted with the effects of damage fluid and external forces, but without the effect of sloshing. We evaluate the dynamic stability in terms of capizing probability based on energy balance mechanics and risk analysis , the method of which was proposed by Umeda [2] to the high speed crafts. As a result, we can predict the dynamic stability quantitatively according to sea state , operating and damage conditions.

• Wind and Structures
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• v.10 no.6
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• pp.543-554
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• 2007

The suspension bridge is situated in an area of complex topography with both open sea and overland turbulence characteristics, and it is subject to frequent typhoon occurrences. This paper investigates experimentally the possible vortex shedding events of the structure under high wind and typhoon conditions. A single-degree-of-freedom model for the vibration of a unit bridge deck section is adopted to determine the amplitude of vibration and to estimate the parameters related to the lifting force in a vortex shedding event. The results of the studies are presented in a companion paper (Law, et al. 2007). In this paper, statistical analysis on the measured responses of the bridge deck shows that the vibration response at the first torsional mode of the structure has a significant increase at and beyond the critical wind speed for vortex shedding as noted in the wind tunnel tests on a section model of the structure.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.3
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• pp.298-307
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• 2016

In the building process of FPSOs(floating production, storage and offloading units) is the increasing demand of high performance piping joints that can be installed on its turret system and maintain smooth and long-term flow of ultra-high pressure crude oil, being subjected to external excitations such as wind and wave on the sea. Following such a trend, in this paper, a new-type piping joint of four effective degrees of freedom has been designed, and its dynamic characteristics predicted through mathematical modeling and computer simulations. Moreover, via an example it was shown how the yaw motion in particular can be independently controlled for future durability test despite strong kinetic couplings.

• Bulletin of the Society of Naval Architects of Korea
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• v.21 no.1
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• pp.3-12
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• 1984

Up to now, it has been common to treat the maneuvering motion of a ship as a 3-degree-freedom motion i.e. surge, sway and yaw on the sea surface, for the simplicity and mathematical calculation, and it is quite acceptable in the practical point of view. Meanwhile, considering the maneuverability of a ship under the special conditions such as in irregular waves, in wind or at high speed with small GM value, it is required that roll effect must be considered in the equation of ship motion. In this paper the author tried to build up the 4-degree-freedom motion equation by adding roll. And then, applying the M.M.G.'s mathematical model and with captive model test results the roll-coupled hydrodynamic derivatives were found. With these the author could make some simulating program for turning and zig-zag steering. Through the computer simulations, the effect of roll to the ship maneuver became clear. The effect of the wind force to the maneuverability was also found. Followings are such items that was found. 1) When roll is coupled in the maneuvering motion, the directional stability becomes worse and the turning diameter becomes smaller as roll becomes smaller as roll becomes larger. 2) When maneuver a ship in the wind, the roll becomes severe and the directional stability becomes worse. 3) When a ship turns to the starboard side, the wind blowing from 90 degree direction to starboard causes the largest roll and the largest turning diameter, and the wind from other direction doesn't change the turning diameter. 4) When a ship is travelling with a constant speed with rudder amidship, if steady wind blows from one direction, the ship turns toward that wind. This phenomenon is observed in the actual seaways.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.1
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• pp.3-30
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• 2011

According to the Article 86 of the United Nations on the Law of the Sea(UNCLOS) the provisions of high seas apply to all parts of the sea that are not included in the exclusive economic zone, in the territorial sea or in the internal waters of a State, or in the archipelagic waters of an archipelagic State. Article 87 also stipulates the freedom of the high seas. International laws on the flight over the high seas are found as follows; Firstly, as far as the nationality of the aircraft is concerned, its legal status is quite different from the ship where the flags of convenience can be applied practically. There is no flags of convenience of the aircraft. Secondly, according to the Article 95 of UNCLOS warships on the high seas have complete immunity from the jurisdiction of any State other than the flag State. We can suppose that the military(or state) aircraft over the high seas have also complete immunity from the jurisdiction of any State other than the flag State. Thirdly, according to the Article 101 of UNCLOS piracy consists of any act of voluntary participation in the operation of a ship or of an aircraft with knowledge of facts making it a pirate ship or aircraft. We can conclude that piracy can de done by a pirate aircraft as well as a pirate ship. Fourthly, according to the Article 111 (5) of UNCLOS the right of hot pursuit may be exercised only by warships or military aircraft, or other ships or aircraft clearly marked and identifiable as being on government service and authorized to that effect. We can conclude that the right of hot pursuit may be exercised only military aircraft, or aircraft clearly marked and identifiable as being on government service and authorized to that effect. Fifthly, according to the Article 110 of UNCLOS a warship which encounters on the high seas a foreign ship, is not justified in boarding it unless there is reasonable ground for suspecting that: (a) the ship is engaged in piracy, (b) the ship is engaged in the slave trade, (c) the ship is engaged in an authorized broadcasting and the flag State of the warship has jurisdiction under article 109, (d) the ship is without nationality, or (e) though flying a foreign flag or refusing to show its flag, the ship is, in reality, of the same nationality as the warship. These provisions apply mutatis mutandis to military aircraft. Sixthly, according to the Article 1 (5)(dumping), 212(pollution from or through the atmosphere), 222(enforcement with respect to pollution from or through the atmosphere) of UNCLOS aircraft as well as ship is very much related to marine pollution. Seventhly, as far as the crime on board aircraft over the high seas is concerned 1963 Convention on the Offences and Certain Other Acts Committed on Board Aircraft(Tokyo Convention) will be applied, and as for the hijacking over the high seas 1970 Convention for the Suppression of Unlawful Seizure of Aircraft(Hague Convention) and as for the sabotage over the high seas 1971 Convention for the Suppression of Unlawful Acts Against the Safety of Civil Aviation(Montreal Convention) will be applied respectively. These three conventions recognize the flag state jurisdiction over the crimes on board aircraft over the high seas. Eightly, as far as reconnaissance by foreign aircraft in the high seas toward the coastal States is concerned it is not illegal in terms of international law because its act is done in the high seas. Ninthly as for Air Defence Identification Zone(ADIZ) there are no articles dealing with it in the 1944 Chicago Convention. The legal status of the foreign aircraft over this sea zone might be restricted to the regulations of the coastal states whether this zone is legitimate or illegal. Lastly, the Arctic Sea is the frozen ocean. So the flight over that ocean is the same over the high seas. Because of the climate change the Arctic Sea is getting melted. If the coastal states of the Arctic Sea will proclaim the Exclusive Economic Zone(EEZ) as the ocean is getting melted, the freedom of flight over that ocean will also be restricted to the regulations of the coastal states.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.1
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• pp.50-59
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• 2000

This paper presents a brief outline of dynamic stability of a damaged ship at final stage of flooding in rough beam wind and waves. One degree-of-freedom, roll equation is adopted with effects of flooding water and external forces due to wind and waves, but without effect of sloshing. We discuss the dynamic stability of the damaged ship in terms of capsizing probability based on risk analysis, the method of which was firstly proposed by Umeda et al.[6] to high speed craft in intact condition. As a result, we can evaluate the dynamic stability of the damaged ship in probabilistic manner according to sea state, operating condition and damage situation.