• Journal of the Society of Naval Architects of Korea
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• v.36 no.4
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• pp.77-86
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• 1999

The bow flare structure of a ship is designed considering wave impact loads largely caused by relative motion of the ship and wave at rough sea. Empirical design is still used because impact phenomenon and structural behaviour due to wave impact load can not examined accurately. The objective of this study is, as the first step, to predict wave impact loads giving the structural damages to the bow flare structure from the damage data inversely, using dynamic nonlinear finite element code LS/DYNA3D, and to perform various parametric studies of wave impact pressure curve for its characteristics, such as peak height, duration time, tail height, rise time, etc.. The followings were obtained from this study: Dynamic structural responses against wave impact loads are largely affected by impact pressure impulse whose amount during duration time until peak deformation is very important.

• Applied Microscopy
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• v.34 no.2
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• pp.83-93
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• 2004

Integumentary structures of the rockfish, Sebastiscus tertius were examined by means of the light and transmission electron microscopy. Stratified epidermal layer consists of supporting cells, unicellular glands, granular cells and mitochondria-rich cells. The epidermal layer could be classified into superficial, intermediate and basal layer by morphology and structure of the supporting cells. Mucous cells of unicellular gland were observed in the superficial and intermediate layer of the epidermis. The mucous materials were identified as acidic and carboxylated mucosubstance by histochemical methods. Club cell has well-developed central vacuole, rough endoplasmic reticula and Golgi complex in the cytoplasm. Granular cells were observed in the superficial layer and contained numerous granules of high electron density. Mitochondria-rich cells are characterized by well-developed microfilaments in cortex and numerous tubular mitochondria in medullar cytoplasm. Three types of pigment cells in the dermal layer could be distinguished with electron density of cytoplasmic inclusions.

• Journal of the korean society of oceanography
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• v.32 no.4
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• pp.163-170
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• 1997

Some CMP gathers acquired from shallow marine seismic reflection survey in offshore Korea do not show the hyperbolic trend of moveout. It originated from so-called swell effect of source and streamer, which are towed under rough sea surface during the data acquisition. The observed time deviations of NMO-corrected traces can be entirely ascribed to the swell effect. To correct these time deviations, a residual statics is introduced using Genetic Algorithms (GA) into the swell correction. A new class of global optimization methods known as GA has recently been developed in the field of Artificial Intelligence and has a resemblance with the genetic evolution of biological systems. The basic idea in using GA as an optimization method is to represent a population of possible solutions or models in a chromosome-type encoding and manipulate these encoded models through simulated reproduction, crossover and mutation. GA parameters used in this paper are as follows: population size Q=40, probability of multiple-point crossover P$_c$=0.6, linear relationship of mutation probability P$_m$ from 0.002 to 0.004, and gray code representation are adopted. The number of the model participating in tournament selection (nt) is 3, and the number of expected copies desired for the best population member in the scaling of fitness is 1.5. With above parameters, an optimization run was iterated for 101 generations. The combination of above parameters are found to be optimal for the convergence of the algorithm. The resulting reflection events in every NMO-corrected CMP gather show good alignment and enhanced quality stack section.

• English & American cultural studies
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• v.18 no.4
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• pp.33-64
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• 2018

Through the experimental narrative construction by authorial divinity, Muriel Spark's novels and films based on her fiction show the difficulty of living like a human being under various inhumane and manipulative circumstances of the modern capitalistic society. By adopting flash-forward, self-reflection, and deceptive omnipotent viewpoints, her work has surprisingly predicted the post-modern trend in which humans are increasingly attracted and interpellated to the digitalized media. Muriel Spark called the recent anesthetic situation by stimulation "a driver's seat" because it is a symbol of how humans should act to maintain the critical subject. Emphasizing the value of self-reflection, religion and morality in the mechanized society, Muriel Spark stressed literature should play the role of helmsman who sails safely in the rough sea. In Muriel Spark's works, God is often synonymous with writers. As a Jewish immigrant she experienced alienation in Scotland, marital violence, prejudices of the London-based publishing world, Nazism, and Watergate. For her, the harsh reality of the modern society needs to be guided and complemented by something beyond human control. But rather than relying entirely on traditional Catholic doctrines such as Graham Greene and Evelyn Waugh, Muriel Spark has taken a personal, religious view of literature and insists that the genuine writer must play God's play. Seeking for the speculative vision for the future of human life in God's plan, she tries to understand the complex twisted motives of human beings which are often far from the ideal form. Simply put, her search of self-reflection, religion and ethics is modeled on the God's plan for the ideal human being who is supposed as the writer with the transfigurative imagination of the trinity.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.3
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• pp.175-181
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• 2021

This study describes the model tests in ice according to the frictional coefficient of an ice-breaking ship and the change in ice resistance by the analysis method for each component of ice resistances. The target vessel is a 90K DWT ice-breaking tanker capable of operating in ARC7 ice conditions in the Arctic Ocean, and twin POD propellers are fitted. The hull was specially painted with four different frictional coefficients on the same ship model. The total ice resistance can be separated by ice breaking, ice buoyancy, ice clearing resistances through the tests in level ice, pre-sawn ice and creep test in pre-sawn ice under sea ice thickness of 1.2 m and 1.7 m. Ice resistance was analyzed by correcting the thickness and bending strength of model ice by the ITTC correction method. As the frictional coefficient between the hull and ice increases, ice buoyancy and clearing resistances increase significantly. When the surface of the hull is rough, it is considered that the broken ice pieces do not slip easily to the side, resulting in an increase in ice buoyancy resistance. Also, the frictional coefficient was found to have a great influence on the ice clearing resistance as the ice thickness became thicker.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.176-179
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• 2006

Tewoo refers to a traditional group of Jeju's rafts for fishing in the rough Jeju sea in the past. We propose a mobile game called 'TewooGwang' based on a fishing boat called 'Tewoo', which has a scenario of conquering the Jeju sea using unique characters symbolizing the Jeju's ocean culture. This game is a new game, which uses a character of the fishing boat 'Tewoo', the background based on only Jeju's features, the high portability of PDA, and multimedia technology. It is different from simple sports games and has various game scenarios according to interactions of Tewoo character. The structure of this game represents a storytelling, which integrates Jeju culture into cyberspace. There are stories in this game and users also can make their own stories. Thus, this game enables hi-directional communications. It presents an imaginative space, which can induce a conflictive structure made by each user, and spatial provability. Many young Jeju tourists will enjoy it because this game provides a dynamic story. Furthermore, we can contribute to serving the value-added Jeju culture of being upgraded one step through this Jeju culture based game.

• Development and Reproduction
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• v.12 no.2
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• pp.195-202
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• 2008

The gonadosomatic index, germ cell differentiation, and the ovarian cycle in female jicon scallop, Chlamys farreri were studied by histologic and cytologic observations. In the early vitellogenic oocyte, the Golgi complex, mitochondria and rough endoplasmic reticulum were involved in the formation of lipid droplets. In the late vitellogenic oocyte, exogenous substances, namely, glycogen particles and lipid granular substances appeared in the germinal epithelium passed into the ooplasm through the microvilli of the envelope. Yolk granules and multivesicular bodies were involved in the formation of proteinecious yolk granules in the late vitellogenic oocyte. Vitellogenesis occurrs by endogenous autosynthesis and exogenous heterosynthesis. The auxiliary cells function as nutritive cells in the formation and development of the previtellogenic and early vitellogenic oocytes in their earlr stages. Monthly changes in the gonadosomatic index were closely associated with ovarian developmental phases. The reproductive cycle of this species can be classified into five stages: early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (June to August), and spent/inactive stage (August to December). Spawning occurred from June to August, and the major spawning season was from July to August when the sea water was at high temperature.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.97-104
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• 2006

Recently the first stage qf construction for Busan new port emerged over the sea surface at the north container terminal site. With this, there are lot of discussions and debates on increasing the water depth at the approaching channel and mooring basin from the existing 15m to 18m by dredging work in order to be able to serve 12,000TEU containership, and at the same time, correction to the reclamation plan of hinterland at the part of Undong Bay qf the new port site. Since the attack of typhoon 'Maemi' in 2003, it is expected that the design wave parameters for coastal and harbor structures in this area would be somewhat changed and so the extreme wave condition at each terminal and tranquility of berthing area does, and therefore, it is necessary to analyze the tranquility at each berth Hence in this study, we constructed a wave model for these conditions and performed simulation together with the circulation model simulation, compared with the field data collected The result showed the increase of the harbor response throughout the basin but not severe condition However, a certain location needs to be prepared for the rough sea condition when a severe typhoon hit the site.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.311-318
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• 2004

It is very important for the safe navigation and fishing operation to ensure the hull response of a fishing vessel in rough seas. This is an experimental study on the dynamical characteristics of ship's motion during operating job and sailing in the real sea. The experiments were carried out on the small stern trawler in operating job and sailing, and then the ship's roll and pitch motion were simultaneously recorded by P/C according to the wave directions. From these data, the statistical properties and power spectra were obtained and the analysis of ship's motions in the both case were made. The results obtained are summarized follows : (1) The amplitudes of pitch motion don't appear a big different between trawl job and sailing, but at bow seas, its in sailing have a tendency to increase more than in trawl job. The amplitudes of roll motion appear a bog different between trawl job and sailing, but at beam sea, that slightly decreasing tendency. (2) The peak period of pitch motion in trawl job and sailing change, but that of roll motion don't change according to the direction of waves. (3) The warp tention cause the motion of hull to be reduce, if the tention of each side have a ballance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.117-124
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• 2005

Recently the first stage of construction for Busan new port emerged over the sea surface at the north container terminal site. With this, there are lot of discussions and debates on increasing the water depth at the approaching channel and mooring basin from the existing 15m to 18m by dredging work in order to be able to serve 12,000TEU containership, and at the same time, correction to the reclamation plan of hinterland at the part of Undong Bay of the new port site. Since the attack of typhoon 'Maemi' in 2003, it is expected that the design wave parameters for coastal and harbor structures in this area would be somewhat changed and so the extreme wave condition at each terminal and tranquility of berthing area does, and therefore, it is necessary to analyze the tranquility at each berth. Hence in this study, we constructed a wave model for these conditions and performed simulation together with the circulation model simulation, compared with the field data collected. The result showed the increase of the harbor response throughout the basin but not severe condition. However, a certain location needs to be prepared for the rough sea condition when a severe typhoon hit the site.