• Journal of Aquaculture
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• v.13 no.2
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• pp.119-128
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• 2000

Exposure to air and increased temperature induced successful spawning in Mytilus edulis, M. coruscus Crassostrea gigas and Pinctata fucata martensii. Developmental durations required for an egg to attain D-shaped larva and the D-shaped larva to reach pediveliger stage were estimated in these bivalves. Size of fertilized eggs was the largest (70.3 ${\mu}m$) in M. coruscus and the smallest (45.3 ${\mu}m$) in P. fucata martensii. At 17$^{\circ}C$, M. edulis and M. coruscus attained D-shaped larval stage within 48 hours after fertilization but those of C. gigas and B. fucata martensiii within 24 and 22 hours at 21 and 26$^{\circ}C$, respectively. The development duration required for a D-shaped larva to attain pediveliger stage was the longest (27 days) in M. coruscus and ranged between 20 and 22 days for the others. The shell length of the pediveliger was the longest (274.9 ${\mu}m$) in C. gigas and smallest (190.9 ${\mu}m$) in P. fucata martensii Length and height of larval shell was highly correlated with each other in all the 4 species. The shell height of C. gigas was more than the shell length beyond the size of 100 ${\mu}m$ shell length. However, shell length of the others was always longer than shell height at the larval stage.

• Journal of Aquaculture
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• v.21 no.1
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• pp.7-12
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• 2008

Toxicity of ten commercial disinfectants(hydrogen peroxide, sodium hypochlorite, chlorine dioxide, povidon iodine, formaldehyde, glutaraldehyde, quaternary ammonium compounds(QAC), didecyl dimethyl ammonium chloride(DDAC), ortho-dichlorobenzene, and copper sulfate) was measured by chinook salmon embryo-214 cell line and three fish species: flounder Paralichthys olivaceus, black rockfish Sebastes pachycephalus, and black sea bream Acanthopagrus schlegelii. The $LC_{50}$ levels of 24 hours acute toxicity with the ten disinfectants were tested in three species of fish. Effectiveness of ten chemical disinfectants were varied by each chemical as well as by species. Hydrogen peroxide showed the higest activity at 201, 269, and 139 ppm in the flounder, the black rockfish, and black sea bream, respectively. DDAC showed the lowest activity at 2.1, 1.0, and 1.5 ppm in the flounder, the black rockfish, and black sea bream, respectively. The highest variation was observed in copper sulfate by both the chemicals and the species.

• Journal of Aquaculture
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• v.21 no.1
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• pp.1-6
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• 2008

We determined the effects of dietary supplements for lactic acid bacteria(LAB) such as Lactobacillus brevis(Lb) and Lactobacillus plantarum(Lp) in juvenile rockfish Sebastes schlegeli cultured in flow-through system for 10 weeks. The experimental diets contained $10^4cfu/g,\;10^6cfu/g\;and\;10^8cfu/g$ level each LAB(Lb-4, Lb-6, Lb-8 or Lp-4, Lp-6, Lp-8), respectively. The effects of LAB supplementation was determined by various factor such as weight gain(WG), specific growth rate(SGR), feeding efficiency(FE) and blood assay. For rearing experiment, Lp-8 treatment had significantly high growth rate than control diet treatment. However, all Lb treatment had no significance effect with control diet treatment. In case of the blood assay, hematocrit(Ht) and hemoglobin(Hb) of fish were not affected by LAB supplemental levels. On the other hand, total cholesterol in plasma of Lb-8, Lp-6 and Lp-8 treatments were significantly low than the control diet treatment. We verified the influence of LAB which was originated from species specificity and amount in diet. Consequently, the dietary supplementation as $10^8cfu/g$ level of L. plantarum could be of help for growth enhancement to the juvenile rockfish.

• Journal of Aquaculture
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• v.21 no.1
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• pp.34-40
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• 2008

This study investigated the effect of rearing conditions on the spawning habit, juvenile growth and larvae development of Marphysa sanguinea, to develop techniques of its artificial seed production. M. sanguinea released trochophore larvae around the burrow when the water temperature was from $18^{\circ}C$ to $22^{\circ}C$. Larvae floated away after staying in the burrow for a while. Larvae secreted mucus eight days after release, covering their whole body with it, and developed ten somites 20 days after release. In preference of juveniles in different grain sizes of sediment, the highest survival rate was made in the grain substrate of $1{\sim}2$ mm in the mean diameter, but the lowest was in the $2{\sim}3$ mm grain substrate. Optimum growth was obtained at the rearing temperature of $24^{\circ}C$(SGR 1.10%), and it reached over $2{\sim}3$ times higher weight gain and specific growth rate than those reared at $21^{\circ}C(0.64),\;18^{\circ}C(0.56)$ and $15^{\circ}C$(0.42) for 50 days. Salinity also made a great difference in the growth and survival rate. The highest weight gain and growth rate were shown when the juveniles were reared at salinity 30 psu.

• Journal of Korea Port Economic Association
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• v.34 no.2
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• pp.1-16
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• 2018

Maritime industry is recognized as a new value-adding and growth engine industry. It provides high value by creating clusters centering on ports. Advanced international ports are also clashing ahead to create clusters, boost profits, and strengthen competitiveness. The Korean government enacted policies for the establishment and upbringing of maritime industrial clusters in 2015. It is very important to understand which maritime industry has a comparative advantage in each region and to establish an integration strategy through maritime industrial clusters. This study analyzes the structure of the maritime industry in the Chungnam province, which is expected to deal with raw materials(mainly oil products), container throughput, and opening of ferry route with China's port. The study analyzed the existing literature on the maritime industry and classified the industry into 5 major categories, 21 sub-categories, and 84 sub-categories in shipping and logistics, shipbuilding, fishery, marine tourism industry, and other industries. Based on the reclassified maritime industry, the structure of the maritime industry in the Chungnam province was analyzed by using location quotient(LQ) and Shift-Share analysis. The study found that the fisheries industry showed the highest value(1.718) in the analysis of LQ, followed by the marine tourism industry(1.092), shipbuilding industry(0.823) and shipping and logistics industry(0.789). The total effect of the maritime industry in Chungnam province was 36,315 and the net growth effect, excluding the national growth effect, was estimated to be 21,321. Based on these results, we classify the maritime industry in the Chungnam province as comparative advantage and comparative disadvantage. The results of this study can be used as basic data for formulating strategies for the construction of the maritime industry cluster in the Chungnam province in the future.

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.1-6
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• 2012

We studied that the effect of stocking density on growth and survival rate of the scallop, Chlamys farreri (initial shell height 32.97 mm and total weight 5.63 g) from June 2002 to October 2003 in the west coast of Korea. C. farreri is usually the west coast of Korea and northern China in the natural habitat of the coastal species. Range of surface water temperature in the study area was $4.3^{\circ}C$ to $25.3^{\circ}C$, salinity 29.2 psu to 32.1 psu, dissolved oxygen 5.32 mg/L to 7.51 mg/L and pH was 7.84 to 8.12, respectively. The stocking densities were 20, 30, 40 and 50 individuals per a compartment of suspension cage in culture beginning. After 16 months from initiation, ranges of shell height and mean total weight were from 64.35 mm to 76.23 mm and from 41.53 g to 64.85 g. The survival rate was from 82% to 100%. The growth rate of the scallop was negatively correlated with the stocking density. The growth of the shell height and total weight were decreased with decreasing of water temperature. Most of mortality of scallop occurred during March to April and September to October. Survival rate in the stocking density was decreased by density increase and was highest in 20 individual a compartment.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.139-146
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• 1976

This survey attempted to determine the overall health situation in Kyunggido in terms of sickness prevalence, sickness distribution, demand for medical care by type, and utilization of medical care. The survey was conducted on 766 households, or 4,065 people, from July 1-31, 1975. The findings from the survey are as follows: 1) In terms of age distribution, 28.7% of the sample was from 10-19, the 40-49 age group was the next largest group, and those over 60 made up 7% of the sample. 2. The education distribution is as follows, 30.4% completed primary school, 22.4% had no formal education, 20.6% attended but did not onplete primary school, and 1.8% attended unversities or higher. 3) In terms of occupation, 55.9% were unemployed or family employees, which represents a large dependent population, 30.4% of the workers were employed in farming or fisheries. 4. The marital status is as follows, 58.8% of the women were married, 32.3% unmarried, and 7.5% divorced. 5) The prevalence rate of mouthy illness was 19.7% of 100 infant, 42.8% became fatally ill within the first year of life. This is a very high percentage compared with more developed nations. 6) Of those reportion on illness, 54.6% sought treatment. The rate of treatment was highest in infants at 77.7%. Us age increased, demand for treatment decreased to 43.1% for those in the aldest age group. The oldest age group also had the highest rate of non treatment at 56.8%. 7) The demand for medical care showed that 65.6% utilized drug stores, 20.2% utilized hospitals and clinics, 5.4% used herbdrug-stores and herb clinices, and 3.9% relied upon folk medicine and withch craft. 8) The utilization of medical facilties by sex is as follows, 65.1% of the men and 66.0% of the women used drug stores, and 19.2% of the men and 20.2% of the women used hospitals and clinics. However, more men (3.5%) were hospitalized than women (1.8%) 9) In terms of out-patient care, the largest age group of males was 10-19 (28.2%), and the largest age group of females was 0-9 (30.8%). There was no sex difference in the use of western pharmacies. Menaged 30-39 and women aged 50-59 were the most frequent users of herb clinics. 10) The rate of receiving treatment at drugstore hospitals went towards declining level in the second case of what While increaing much more at herb clinics and folk medicines in the second case than the first one. 11) After primary utilization of hospitals, 32.7%. of the adults aged 20-59 used drug-stores as a secondary source of care, and 12.8% of children and youth under age 20 continued receiving care at hospitals. 12) After primary utilization of drug-stores, 32.5 % of the adults continued to seek care at drug stores and 1.8% used hospitals. 4.2% of those over age 60 utilized folk medcine and witch craft.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.199-204
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• 2006

Streptococcosis of olive flounder(Paralichthys olivaceus) is an important bacterial disease in Jeju island. In this study, we investigated monthly infection pattern of this disease in different size of the flounder fish. Even though the disease occurred throughout the year, the infection ratio was relatively higher in the months with warm water season. The infection was more prevalent in adult flounder over 30 cm total length compare to these of small size fish. Two infectious species of streptococcosis pathogens were detected by multiplex PCR assay. Detection ratios of Streptococcus iniae and S. parauberis reached up to 46% and 54%, respectively, from June 2003 to May 2005 in Jeju island. S. iniae occurred intensively from September to October, whereas S. parauberis reported from March to May. S. iniae and S. parauberis infections of cultured flounder share some common features, but clinical findings showed considerable differences between two diseases. Distended abdomen, protruded anus and ascitic fluid in the peritoneal cavity are evident lesions detected in S. iniae infection, whereas, flounders infected by S. parauberis showed prominent lesions such as darkened surface and haemorrhaging in the non-ocular side. Both streptococcosis pathogens were sensitive to antibiotics, such as ampicillin and amoxicillin. However, S. iniae strains were more sensitive to doxycycline, erythromycin and oxytetracycline than S. parauberis strains.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.379-384
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• 2012

Bitter gourd (Momordica charantia L.) has long been used for food and medicinal plant in Korea, China and Japan. This study aimed at evaluating productivity, and vitamin-C and charantin contents in bitter gourd (Momordica charantia L.) accessions. The contents of charantin of these two accessions were analyzed using HPLC with the UV-diode array detection. The highest fruit yield was observed in accessions, 'BG1' and 'BG7.' The vitamin-C contents of fruits in these two high-yield bitter gourd accessions, 'BG1' and 'BG7,' depended on days after fruit set and were highest in 24 days and 17 days after fruit set, respectively. The charantin contents of the two accessions were different according to the number of days after fruit set. The charantin content of 'BG1' was highest in fruits harvested at 24 days and followed by 15 days after fruit set. The charantin content of 'BG7' was highest in fruits harvested at 13 days and followed by 16 and 19 days after fruit set. The charantin contents of 13 M. charantia accessions with relatively high yield potential were analyzed and three accessions, 104615, K169995 and NS454, were selected based on their relatively high yield and charantin content. These accessions will be used for breeding program and processed foods.

• Journal of Navigation and Port Research
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• v.30 no.5 s.111
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• pp.415-420
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• 2006

Urinalyses have been conducted for 28 crew's in H University's training ship and creatine and uric acid turned out to be higher in all ages, which can be inferred that board job has caused negative impact on kidney and/or malfunction In addition, TC and HDL-C, LDL-C ha; decreased, however, TG has increased after the navigation. All different positions including officer, crew, decker, engineer and radio part showed the similar pattern TC and HDL-C has decreased in 30s, 40s and TG has increased in 30s. A few of the 30's show extremely high TG rates so hyperlipidemia is suspected. 7 members turned out positive for UBG test and 5 positive for PRO test. Especially there was only one UBG positive before the navigation but, 7 members has become positive, which means the one-month long-tenn navigation has definite impact on the liver cell function.