• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.4
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• pp.413-420
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• 2017

The increase in the number of mud shrimps Upogebia major is a concern because of their negative effects on shellfish aquaculture, including Manila clam Venerupis philippinatum along the west coast of Korea. This study developed a behavioral analysis system for aquatic animals using a set of monochromatic light-emitting diode (LED) modules covering the visible light range at similar intervals. Movements of mud shrimp were monitored using a tracking system under illumination with infra-red light and an LED of 660 nm wavelength without provoking stimulation. The minimum light intensity needed to induce a photoresponse by the mud shrimp was $10{\mu}mole/m^2/s$ under the conditions tested. Of the six kinds of LED illuminations tested, the most sensitive response was obtained with illumination with the 505 nm LED, followed in order by LEDs with peak wavelengths of $525nm{\fallingdotseq}465nm$ > $405nm{\fallingdotseq}590nm$ > 660 nm. These findings should help to identify LED sources that efficiently induce movement of the mud shrimp and also for monitoring movement without stimulating.

• The Plant Pathology Journal
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• v.27 no.2
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• pp.148-155
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• 2011

Our previous sequence and phylogenetic analyses of the Korean Rice stripe virus (RSV) suggested possible genetic reassortment of RNA segments, but whether this RNA variation contributed to the recent RSV outbreaks in Korea is yet unclear. To further clarify these RSV-RNA segment variations, we developed a reverse transcription-polymerase reaction/restriction enzyme (RT-PCR/RE) analysis-based method. We identified five REs, including DraI, EcoR1, NdeI/AseI, and SpeI, that could differentiate RSV RNA 1-4 subtypes, respectively. Our RT-PCR/RE results provided a clear pattern of RNA reassortment, i.e., different groups of isolates having their RNA segments derived from two to three different RSV ancestors, such as from Eastern and Southwestern Chinese or Japanese M and T isolates. We also found that the migratory small brown planthopper from Eastern China caught by aerial net traps that possesses RSV-RNA3 genotypes corresponds mainly to Eastern China, with a few for Southwestern China based on RT-PCR/RE, sequence and phylogenetic analyses, indicating that RSV populations in Eastern China may also have strong RNA variation. The development of an RE analysisbased method proved a useful epidemiological tool for rapid genotyping and identification of mixed infections by RSV strain and by different subtype.

• The Journal of Korean Society for School & Community Health Education
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• v.12 no.1
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• pp.117-129
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• 2011

Objectives: The purpose of this study was to introduce of the Urbani School Health Kit (USHK) and to investigate the adaptability to Korean situation. Methods: The authors analyzed the contents of USHK developed by the health promotion team at the Western Pacific Regional Office of World Health Organization (WHO WPRO) in collaboration with health promotion experts at University of the Philippine Open University, and by observing health classes using the USHK in Angono elementary school in Manila, Philippines. Results: The following are the characteristics of USHK: 1) The USHK was composed of a teacher's guide and six books targeted to two groups of children: ages 5~6 years and 10~12, and an integrated package containing materials that can be used to support health education and health promotion activities in elementary schools. 2) The USHK could be integrated in the curriculum to reduce the burden of teacher's class preparation time and help teachers conveying clear and accurate health messages in their classes. 3) Several evaluation tools such as pre-test post-test quizzes, self-evaluation tools, observer checklists, and evaluation interview protocols were developed to monitor and evaluate whether USHK was useful, helpful, and appropriate. Conclusions: We found that USHK was a practical tool for supporting health promotion in elementary schools and could be applicable to health promoting schools in Korea if it were modified to address Korean school health problems.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.486-494
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• 2014

IMO adopted comprehensive revisions to the International Convention and Code on Standards of Training, Certification and Watchkeeping (STCW) at diplomatic conference in Manila, Philippine in June 2010. In Korea, the legal amendment of Korean Marine Officers Act has been proposed to apply revised STCW convention to The Korean Law. The Korean Marine Officers Enforcement Ordinance Act currently working on follow-up and this legislation was passed in Legislation and Judiciary Committee. This thesis would like to look into the current status of how to apply the Electro-Technical Officers standard and license system from the Korean Marine Officers Act to be revised. Also, This study aims to effectively improve for Korean Marine Officers Enforcement Ordinance of Electro-Technical Officers system and to provide the policy proposal.

• Journal of Korea Port Economic Association
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• v.19 no.2
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• pp.1-32
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• 2003

The purpose of this study is to identify and evaluate the competitiveness of ports in ASEAN(Association of Southeast Asian Nations), which plays a leading role in basing the hub of global logistics strategies as a countermeasure in changes of logistics environments. This region represents most severe competition among Mega Hub ports in the world in terms of container cargo throughput at the onset of the 21st century. The research method in this study accounted for overlapping between attributes, and introduced the HFP method that can perform mathematical operations. The scope of this study was strictly confined to the ports of ASEAN, which cover the top 100 of 350 container ports that were presented in Containerization International Yearbook 2002 with reference to container throughput. The results of this study show Singapore in the number one position. Even when we compare with major ports in Korea (after getting comparative ratings and applying the same data and evaluation structure), the number one position still goes to Singapore and then Busan(2) and Manila(2), followed by Port Klang(4), Tanjung Priok(5), Tanjung Perak(6), Bangkok(7), Inchon(8), Laem Chabang(9) and Penang(9). In terms of the main contributions of this study, it is the first empirical study to apply the combined attributes of detailed and representative attributes into the advanced HFP model which was enhanced by the KJ method to evaluate the port competitiveness in ASEAN. Up-to-now, none has comprehensively conducted researches with sophisticated port methodology that has discussed a variety of changes in port development and terminal transfers of major shipping lines in the region. Moreover, through the comparative evaluation among major ports in Korea and ASEAN, the presentation of comparative competitiveness for Korean ports is a great achievement in this study. In order to reinforce this study, it needs further compensative research, including cost factors which could not be applied to modeling the subject ports by lack of consistently quantified data in ASEAN.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.390-392
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• 2012

Diarrhetic shellfish poisoning toxins were investigated by liquid chromatography-electrospray ionization mass spectrometry (LC-MS/MS). Okadaic acid (OA), Dinophysistoxin-1 (DTX1), Pectonotoxin2, (PTX2) and Yessotoxin (YTX) in bivalves were quantified. OA were found in four samples; mussel Mytilus edulis (0.001 ${\mu}g/g$), Oyster Crassostrea gigas (0.004 and 0.001 ${\mu}g/g$) and manila clam Ruditapes philippinarum (0.001 ${\mu}g/g$). DTX1, PTX2, and YTX were not detected from all of the samples examined.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.5 s.118
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• pp.54-59
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• 2006

Paperboards used for linerboard of corrugated fiberboard box were coated with different concentrations of polylactic acid (PLA) solution and the effects of harsh environmental conditions such as high humidity and temperature (96% RH at $30^{\circ}C$ for up to 5 days), and freeze-thaw ($-20^{\circ}C$ for a day and then thaw at room temperature for 30 min) conditions on the ring crush (RC) strength of the boards were investigated. One to five percent PLA solutions were coated onto SC manila linerboard ($20{\times}27cm$) using a No. 20 wire bar coater and the ring crush strength was measured using a computer-controlled Advanced Universal Testing System in accordance with TAPPI Test Method T 822 om-93. The RC strength increased significantly when the concentration of coating solution increased and appreciable changes were found when the concentration increased from 0 to 2% (P<0.05). Similar pattern of results was found after 5-day storage at $30^{\circ}C$ and 96% RH. Although such highly humid condition increased moisture content in the samples up to 3.95 from 0.97 times, the RC strength decreased in the range from 29.9 to 48.5%. The freeze-thaw treatment increased the moisture content only up to 1.27% and the reduction in the RC strength ranged from 21.1 to 28.1 %. The results were promising: the samples coated with 5% PLA solution showed 29.9% reduction in the RC strength while that of control was 48.5% during highly humid condition stated above.

• The Korean Journal of Malacology
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• v.26 no.3
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• pp.211-215
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• 2010

The genus Perkinsus are parasitic protozoans that cause massive inflammatory responses in infected marine shellfish worldwide. This ultimately leads to great economic losses. This study examined the effects of water temperature and salinity on the formation of prezoosporangia and zoosporangia in order to understand the ecology of the pathogens. The induction of prezoosporangia from trophozoites occurred readily at higher water temperatures (20 and $30^{\circ}C$) and they had larger diameters than those incubated at lower temperatures (4 and $10^{\circ}C$). The formation of zoospores in prezoosporangia was also strongly influenced by water temperature and salinity; prezoosporangia exposed to water temperatures of 20 and $30^{\circ}C$ and salinities of 20 and 30 ppt had high rates of zoosporulation, while no or very low rates of zoosporulation were observed at temperatures below $10^{\circ}C$ or salinity below 10 ppt. Our data will be useful for the development of strategies to counter P. olseni proliferation in Korean waters.

• Membrane and Water Treatment
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• v.10 no.1
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• pp.91-97
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• 2019

Application of bioretention systems in Korea is highly considered due to its minimal space requirements, appropriateness as small landscape areas and good pollutant removal and peak hydraulic flow reduction efficiency. In this study, the efficiency of two lab-scale bioretention types having different physical properties, media configuration and planted with different shrubs and perennials was investigated in reducing heavy metal pollutants in stormwater runoff. Type A bioretention systems were planted with shrubs whereas type B were planted with perennials. Chrysanthemum zawadskii var. latilobum (A-CL) and Aquilegia flabellata var. pumila (A-AP) respectively were planted in each type A bioretention reactors while Rhododendron indicum linnaeus (B-RL) and Spiraea japonica (B-SJ), respectively were planted in each type B bioretention reactors. Results revealed that the four lab-scale bioretention reactors significantly reduced the influent total suspended load by about 89 to 94% (p<0.01). Type B-RL and B-SJ reactors reduced soluble Cr, Cu, Zn, and Pb by 28 to 45% that were 15 to 35% greater than the soluble metal reduction of type A-CL and A-AP reactors, respectively. Among the pollutants, total Cr attained the greatest discharged fraction of 0.52-0.81. Excluding the effect of soil media, total Pb attained the greatest retention fraction in the bioretention systems amounting to 0.15-0.34. Considering the least discharge fraction of heavy metal in the bioretention system, it was observed that the bioretention systems achieved effectual reduction in terms of total Cu, Zn and Pb. These findings were associated with the poor adsorption capacity of the soil used in each bioretention system. The results of this study may be used for estimating the maintenance requirements of bioretention systems.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.1030-1035
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• 2021

Diving fishermen are demanding permission to use an inspirator that can efficiently catch Manila clam; however, coastal fishermenargue that the use of inspirator devastates the seabed and depletes fishery resources. Therefore, the aim of this study was to evaluate the fishing power of diving gears and its effect on coastal fishing grounds. The average time taken to fish in the seabed (4 m²) with a rake, water gun, and an inspirator was 11.17 min, 13.33 min and 7.81 min, respectivelyThe values of catch per unit time with a rake, water gun, and an inspirator were 3.35 kg/min, 2.26 kg/min, and 3.83 kg/min, respectively. Suspended sediments were observed the most in the water gun fishing area, and were observed more in April when fishing was not carried out than in February when fishing was carried out. However, the difference in the amount of sediment deposited in the fishing area using the three-fishing gears was very small. For an accurate analysis of the impact of the fishing gears on the seabed, supplementary tests such as grain size analysis and changes in benthic organisms need to be conducted.