• Journal of the Korean Operations Research and Management Science Society
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• v.13 no.1
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• pp.13-13
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• 1988

This paper considers the sequencing problem in mixed model assembly lines with hybrid workstation types and sequence-dependent setup times. Computation time is often a critical factor in choosing a method of determining the sequence. We develop a mathematical formulation of the problem to minimize the overall length of a line, and present a tabu search technique which can provide a near optimal solution in real time. The proposed technique is compared with a genetic algorithm and a branch-and-bound method. Experimental results are reported to demonstrate the efficiency of the technique.

• Natural Product Sciences
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• v.5 no.2
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• pp.93-96
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• 1999

A new ergosteryl myristate (1) and ergosterol (2) have been isolated from the organic extract of the mycelium of unidentified marine algicolous fungus, isolate MF001. The structure of a new compound was assigned on the basis of comprehensive spectroscopic analyses and chemical synthesis.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1859-1862
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• 2014

• Ocean and Polar Research
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• v.42 no.4
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• pp.283-292
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• 2020

Oncaea prendeli Shmeleva, 1966 is redescribed here based on a specimen collected using a fine-mesh net in the epipelagic layer in the south sea of Jeju Island, Korea. The Korean specimen is generally similar to Mediterranean specimens in terms of morphological characteristics, but it shows a few minor differences in a slightly larger length-to-width ratio for the distal endopod segment of the antenna, a relatively shorter caudal seta IV, and additional ornamentation on the maxillule and maxilla. This species is distinguishable from the most similar congeneric species, O. tregoubovi Shmeleva, 1968, and three species of the genus Spinoncaea Böttger-Schnack, 2003 by the distal and lateral armature of the antenna, ornamentation on the female maxilliped, spine number on the endopod of leg 2, and proportional length of setae on the caudal ramus. Moreover, spine lengths on the exopods of legs 2-4 are proposed as new morphological characters for the identification of congeners. This is the first record of O. prendeli in Korean waters.

• Fisheries and Aquatic Sciences
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• v.3 no.3_4
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• pp.213-216
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• 2000

The marine actinomycetes are very interesting microorganisms for finding of new antibiotics, because they are inhabited in marine environmental conditions, such as salinity, organic material and low concentration of nutrient components that are differ from those of land. In this study, the actinomycetes producing antibiotics from sea waters and bottom deposit samples collected at east coast of Korea were investigated to invent new antibiotics. Nine actinomycetes strains having the antimicrobial activity of 431 actinomycetes were selected from sea waters and bottom deposit samples. Among the 9 strains, the strain having the highest antimicrobial activity was classified to Streptomyces sp. and named Streptomyces sp. NS 13239.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.2
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• pp.41-45
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• 2016

Chemical investigation of a marine-derived fungus, Penicillium sp. 108YD020, resulted in the discovery of six bile acid derivatives, glycocholic acid (1), glycocholic acid methyl ester (2), cholic acid (3), glycochenodeoxycholic acid (4), glycodeoxycholic acid methyl ester (5), and cholic acid methyl ester (6). The structures of six bile acid derivatives 1-6 were determined by the detailed analysis of 1D, 2D NMR and LC-MS data, along with chemical methods and literature data analysis.

• Development and Reproduction
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• v.21 no.1
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• pp.19-33
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• 2017

Optimum concentrations of anesthetic clove oil and anesthetic lidocaine-HCl were determined for a species of adult marine medaka, Oryzias dancena, over a range of salinity conditions, and investigated in a transport simulation experiment by analyzing various water and physiological parameters. Research indicated that the higher the concentration of anesthetic at each salinity, the shorter the anesthesia time at each salinity. At each concentration, fish were anesthetized slower at water salinities over 10 ppt (P<0.05). Anesthesia time at 10 ppt was faster than any other salinity. In 10 ppt salinity, the dissolved oxygen (DO) concentrations and respiratory frequencies of the clove-oil-administered groups decreased until 48 hours (P<0.05), whereas the $NH_4{^+}$ and $CO_2$ concentrations increased until 48 hours (P<0.05). In same period, the DO, $NH_4{^+}$, and $CO_2$ concentrations and respiratory frequencies all decreased as the clove oil concentration increased (P<0.05). The trends in the DO, $NH_4{^+}$, and $CO_2$ concentrations and respiratory frequencies in the lidocaine-HCl-administered groups were similar to those in the clove-oil-administered groups. In conclusion, clove oil and lidocaine-HCl are effective anesthetics, improving the transportation of the marine medaka. The results from this study will contribute to safe laboratory handling of the marine medaka, which are commonly required by many research studies and experiments.

• Ocean and Polar Research
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• v.44 no.4
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• pp.319-329
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• 2022

The paramyxean parasite Marteilioides chungmuensis infects the cytoplasm of the eggs of Pacific oysters Crassostrea gigas , resulting in spawning failure of the infected females. Such infected eggs appear as bump-like nodules on the body in late fall when most of the uninfected females complete spawning. In this study, we estimated the quantity of the infected eggs using an enzyme-linked immunosorbent assay (ELISA), which is destroyed by M. chungmuensis parasitism. In December, the infected oysters collected from Tongyoung on the south coast exhibited numerous yellowish bump-like nodules as signs of infection. In histology, the infected oysters exhibited mature eggs in the follicle, which were heavily infiltrated by hemocytes. ELISA indicated that the infected egg mass accounted for 7.52±5.50 percent of the body weight, suggesting the ovarian parasite causes substantial reproductive loss. Histology also indicated that the infected oysters are in a poor nutritional condition, as the digestive gland atrophy (DGA) level is comparatively higher than the uninfected oyster. The total carbohydrate contents in the infected oysters (108.68±44.41 mg/g dry wt) were significantly lower than in uninfected oysters (269.76±50.97 mg/g dry wt), suggesting that M. chungmuensis parasitism also affected the energy storage capacity of the host during the resting stage.

• Ocean and Polar Research
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• v.26 no.2
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• pp.165-172
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• 2004

Research activities on the fields of marine biotechnology becomes active not only in developing countries but also in Asian countries. Among those countries China recently initiate the national marine biotechnology R&D program. Since 1996, marine biotechnology has been approved to be a subject of the National High Technology Research and Development Program of China as 863 program. In the first five years from 1996 to 2000 and successively in the second five years from 2001 to 2005, Marine Biotechnology R&D 863 program has been funded by Chinese government with 97.5 million RMB and then more than 200 million RMB, respectively. Under this program there are mainly six R&D subjects of marine biotechnology; 1. Breeding engineering, 2. Control of the disease, 3. Production system and culture facilities, 4. Marine drug and bioproducts, 5. Functional genes and genomics, 6. Breeding of the saltresistant plants. In this paper the research activities and results of 863 program were introduced, and from chinese cases we could leam how we plan and perform the marine biotechnology program of Korea in future.

• Ocean and Polar Research
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• v.40 no.3
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• pp.177-190
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• 2018

This study seeks to analyze trends in Korean government support for marine biotechnology R&D investment. The quantitative analysis proposed in this paper provides useful data to inform government policy making decisions in relation to R&D investment in the marine biotechnology. Data used in this study is from NTIS (National Science & Technology Information Service) DB. Empirical results indicate that national R&D investment in the area of marine biotechnology has recently been increased in terms of the number of R&D programs and the amount of R&D investment. The results also show that the R&D programs in the area of marine biotechnology involve various Ministries of the government of Korea, although the Ministry of Oceans and Fisheries (MOF) performed a key role in the R&D investment in the marine biotechnology. Finally, the results of social network analysis in this study reveals that most of the R&D programs in the area of marine biotechnology seeks the development of new materials using unique features of marine bioresources.