• Journal of Fisheries and Marine Sciences Education
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• v.21 no.3
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• pp.373-389
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• 2009

The aims of this study are to examine urgent problems for reorganization into future-proof large purse seine fisheries in order to positively cope with rapidly changing domestic and foreign fisheries circumstances. First, this paper provides current situations of the large purse seine fisheries. The current situations of it are composed of fisheries influence such as vessel number, vessel power, and fisher number, use of resource and fishing places, and changes in products and sales of species caught by the large purse seine. Secondly, this paper reviews current problems of the large purse seine fisheries including cost reduction and increase of value added. Thirdly, this paper suggests basic development direction and countermeasures for strengthening competitiveness of the large purse seine fisheries. In conclusion, urgent problems of the larger purse seine fisheries can be summarized as inefficiency of distribution structures and retarded landing system and facilities as well as the worse of profitability according to shrink of fishing places, reduction of products, lack of workers, and increase in oil price. To solve the urgent problems, the large purse seine fisheries should be changed into an industry with low cost and high efficiency, and also need to introduce of new production system, strengthen autonomous management of natural resource, and increase in value added to products.

• Journal of Ocean Engineering and Technology
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• v.26 no.3
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• pp.13-19
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• 2012

Recently, as the importance of the interior noise in a ship cabin has risen, ship builders have becomeconcerned about the use of noise reduction panels to reduce cabin noise. The results of previous researches have been based on analytical and experimental methods using simple sandwich panels. However, panel structures are becoming more complex to improve the transmission loss. Thus, researches that analyze the transmission loss of a panel are reaching the limit of study. This paper reports on research that was performed to determine the sound transmission characteristics of multi-complex panels applicable to high value-added vessels. It presents comparisons between analytical methods and experimental results by using a mini-reverberant chamber with components of sound attenuation panels, including the core and surface materials. The sound transmission loss of multi-complex panels are also analyzed in terms of the influences of the inside perforate plates and air gap thickness on the attenuation. Finally, the multi-complex panel with the highest noise attenuation is proposed based on the analysis results and experimental results in mini-reverberant chamber, which wereverified using a real-size reverberant chamber.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.12
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• pp.1210-1215
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• 2010

Unit cabin means room, which is installed in the high value-added vessel such as drill ship, offshore platform and FPSO, after pre-assembled. In order to develop the noise control design for a unit cabin, a variety of acoustic tests such as sound absorption, transmission and radiation measurements were carried out by using the deckhouse mock-up. From the tests, it was found out that the sound transmission loss between cabin and corridor was 13 dB below than FPSO standard and the combined noise level of the unit cabin was dominated by the radiated noise from wall panel in low frequency range. Based on the test results, design guidelines for the noise control of the unit cabin were fully established, such as the improvement of sound transmission loss between the cabin and corridor, and radiated cabin noise reduction.

• Journal of the Korea Furniture Society
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• v.20 no.6
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• pp.575-580
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• 2009

This study was carried out to manufacture wooden vessels by small diameter wood and wasted wood of Castanea crenata Sieb. et Zucc, which has been largely planted in southern area. We made spice set, tea box set, cookie vessel set, bowl set and accessory set. With the development of edged tools, the human species has been able to fashion wood to change and enhance its environment - one only has to look at the history of all cultures to see examples of wooden artifacts and structures. Even with the development of synthetic materials and the progress of automated, mechanized production of wood and wood products, the raw material is still processed by traditional methods to meet a never-ending demand for products made from this most desirable natural material. Chestnut wood has high added value and natural color grain and is very useful for wooden vessel. Thinned low grade trees can be used to produce wooden vessel. Therefore this result can promote thinning and produce good forestation.

• KSBB Journal
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• v.15 no.1
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• pp.1-8
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• 2000

The diffusion effect of simulated gastric juices into the various alginate vessel containing each biopolymer such as 0.3% soluble starch, whey, corn starch, agar, locust bean gum, guar gum, gum arabic, pectin, gelatin and 0.15% xanthan gum was tested by measuring the change of pH in the vessel. The degree of viability of bifidobacteria entrapped in each bead containing biopolymers was corresponded with the degree of diffusion inhibition of hydrogen into the each vessel. Therefore, The determination of diffusion inhibition of simulated gastric juices into the various vessel by measuring the change of pH in the vessel may be effectively used as the simple method to select the optimal entrapment lattice for the improvement of bifidobacteria viability. Bifidobacteria entrapped in alginate bead containing 0.15% xanthan gum whose lattice showed the lowest hydrogen diffusion were more significantly tolerant against bile salts and hydrogen peroxide than untrapped bifidobacteria. It was also observed that the viability of bifidobacteria entrapped in bead was nto nearly changed in milk adjusted pH 4.5 with organic adids at $4^{\circ}C$ for 10 days. Therefore, use of alginate containing 0.15% xanthan gum as a cell matrix for entrapping bifidobacteria was expected to improve the viability of bididobacteria in fermented milk products and develop the high value-added products.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.382-389
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• 2021

By applying super-high pressure (150-250 MPa) to a sealed pressure vessel, it is possible to make oyster shucking machine that automatically opens two-sheet shellfish or oysters. Possibility of developing a shucking machine was confirmed by identifying the working pressure for meat of oysters produced in the southern coast and conducting sensory evaluation of meat oysters. As a result of confirming the shucked oysters under super-high pressure of 150 MPa in the pressure vessel, the number of type A with separated shells and well-separated meat was 22 and type B with both shells and internal meat and shells not separated. For the oysters that were treated at 175 MPa, there were 58 type As with shell separated and meat well separated and 42 type Bs without oyster shells and insides. When looking at the oysters shucked at 200 MPa in the pressure vessel, the number of type A was 86 and type B was 14 accounting for 86% of oysters with good marketability. As a result of shucking oysters by applying 250 MPa, 96% type A oysters and 4% type B oysters were obtained from the total specimen. The total specimen oyster weight used in the conducted experiment was 6 kg, the average oyster shell weight was 3.99 kg and the average oyster meat weight was 1.25 kg. Therefore, the fatness of oyster meat, which measures the added value of oysters, is 20.8%. Sensory evaluation was conducted on thinned oysters by hand and type A oysters shelled by machine with an operating pressure of 200 MPa. The hand-worked oyster sample scored 4.7 points only in salty taste, and scored 5.0 or higher in color, shape, smell, fishy taste, texture and preference.

• Journal of Ocean Engineering and Technology
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• v.30 no.3
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• pp.201-207
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• 2016

In this paper, an aluminum pressure vessel (cylinder) for a 200 m water depth is designed and analyzed. Because of their lack of usage in the deep sea, only a few papers about pressure vessels subjected to external pressures have previously been published. Moreover, the high level of imported external-pressure-vessel products limits the academic pursuit. Yet, research on internal pressure vessels is widely available because of their broad usage at onshore. This paper presents the process of basic designing and modelling of pressure vessels using the design rules of American Standard of Mechanical Engineering (ASME) Section VIII Division 1. To promote understanding, finite element analysis (FEA) result of an existing sample cylinder which was not designed by ASME code is compared with the design obtained in this paper. Several methodologies are used for the finite element analysis, including rectangular, cylindrical, and axisymmetric coordinate, to attain an accurate stress result. Same dimensions except the thickness of the cylinder and loading condition of 0.200 MPa was given for the current study. Finally, a rigorous design procedure is added for the bolt and boundary conditions of the cylindrical body and its ends. The obtained stress level satisfies the allowable design stress value specified in the ASME code.

• Journal of Korea Port Economic Association
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• v.27 no.1
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• pp.155-183
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• 2011

The purpose of this paper is to analyze competition status of Korean and Chinese vessels in the EU market. To achieve this purpose, this study uses Market Share Index, Export Bias Index, Trade Specialization Index, Export Similarity Index, and Market Share Expansion Ratio-Export Similarity Deepening Ratio as analyzing method. The statistical data used in this study are obtained from the trade statistics for 5 years(2005-2009) produced by Korean International Trade Association. The results of this study show that Korean ships are less competitive than Chinese ones in the EU export market in that Korea does not export various kinds of ships but export some restricted kinds of vessels even in the competitive ship, implying that Korea has been gradually losing its competitiveness. These results suggest that Korea should improve the competitiveness of shipbuilding industry by pursuing such differentiated strategies as exporting high value-added vessels while keeping on maintaining Korea's dominance over its competitive ships to overcome China's competitive advantage in the EU region.

• Journal of the Korean Applied Science and Technology
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• v.27 no.2
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• pp.114-122
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• 2010

Hydroxy fatty acids have gained important attentions because of their special properties such as higher viscosity and reactivity compared to non-hydroxy fatty acids. The new bacterial isolate Pseudomonas aeruginosa (PR3) had been well studied to produce mono-, di-, and tri-hydroxy fatty acids from different unsaturated fatty acids. Of those hydroxy fatty acids, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) was produced with high yield from oleic acid by P. aeruginosa PR3. Mostly, the substrates used for the production of hydroxy fatty acid by microorganisms were free fatty acids or synthetic lipids. However, it is highly plausible to use vegetable oils containing oleic acid such as olive oil for DOD production by P. aeruginosa PR3. As a first step to address the utilization of olive oil as a substrate for DOD production, we tried to determine the effect of vessel type on DOD production from olive oil by P. aeruginosa PR3. Of two different flask types of normal flask and baffled-flask, baffled-flask was highly effective for DOD production with all the media tested. Maximum increase of productivity by baffled-flask represented 221% with the medium supplemented with whey powder instead of lactose. Results from this study demonstrated that vessel type and medium composition could be both significant factors for DOD production from olive oil by P. aeruginosa PR3.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.133-138
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• 2001

In this study, an attempt was made to increase the survival rate of bifidobacteria entrapped in alginate in the gastrointestinal tract, and to investigate the potential industrial applications, for example lyophilized capsules and yogurt. First, the protective effect of various food additives on bifidobacterial survivability was determined after exposure to simulated gastric juices and bile salts. The additives used in this study were skim milk (SM), polydextrose (PD), soy fiber (SF), yeast extract (YE), chitosan (CS), $\kappa$-carageenan ($\kappa$-C) and whey, which were added at 0.6% concentration (w/v) to 3% alginate-bifidobacterial solution. In the simulated gastric juices and bile salts, the protective effect of 0.6% skim milk-3% alginate (SM-A) beads on the survival rate of bifidobacteria proved to be higher than the other additives. Second, the hydrogen ion permeation was detected through SM-A vessel without bifidobacterial cells at different SM concentrations (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%). There were no differences in terms of the pH decrease in SM-A vessels at 0.6%, 0.8%, and 1.0% (w/v) SM concentrations. The survival rate of bifidobacteria in SM-A beads would appear to be related to the SM buffering capacity against hydrogen ions and its tendency to reduce the pore size of bead. In this experiment, the survival rate of bifidobacteria entrapped in beads containing 0.6% SM showed the highest viability after exposure to simulated gastric juices for 3h, thereby indicating that 0.6% SM is the optimum concentration fir 3% alginate bead preparation. Third, the effect of SM-A beads on the freeze-drying and yogurt storage for 10 days was investigated. SM-A beads were found to be more efficient for freeze drying and yogurt storage than untrapped cells and the alginate bead. Consequently, the survival rate of bifidobacteria entrapped in SM-A beads was increased in simulated gastric juices, bile salts and probiotic products, such as lyophilized capsules and yogurt, SM-A beads can be expected to produce high value probiotic products.