• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.2
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• pp.156-163
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• 2002

In order to development the construction and dimension of fishing gear for gizzard shad coastal purse seine, first of all investigated to the sinking speed and underwater geometry of net, behaviour of fish school to the net during the fishing operation In the field. The results obtained are summarized as follows; 1. Average sinking speed of net was 13cm/sec in bunt, 9.0cm/sec and 9.5cm/sec in 170m and 280m of center, 4.9cm/sec in end wing side, therefore was fastest in start of shooting and decreased gradually during the shooting process. 2. The most of leadline was reached in bottom from the shooting immediately to hauling time and the mean depth of timber bar used equipment for the escaping prevention of fish school was within the 2.7m. 3. The fish school of gizzard shad was appearanced higher density and remained to the most time in bottom than the surface and repeated to vortical movement, and its tendency to distinct in rapid time of tide current. 4. Behaviour of fish school in the net was showed to the vortical movement by sinking and rising immediately with the shooting of net and then divide with the two shape to follow round the wall of net and no patterns straightly movement in the net, and tendency easily catched in fish school of the wall of net. 5. Escaping of fish school in the gap of wing side was to busy after that seting the timber bar, therefore its function for escaping prevention of fish school was very lowed. 6. Escaping behaviour of fish school was differenced with the depth of fishing ground, the above 20m escaped to busy through the below in ledline because the sinking speed of fish school is fast than the net.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.3
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• pp.131-138
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• 1988

Collection of organisms for the fisheries resources community were obtained with a set net during 8 months between May, 1985 and May, 1986 on the coast of Pukchon, Cheju Island, Korea. Most of organisms, representing 36 species, were less than 20cm $(93\%)$ in length, and 130g $(91\%)$ in weight. The four most abundant species were jack mackerel, Trachurus japonicus ; squid, Todarodes pacificus : damsel fish, Chromis notatus : and rabbit fish, Siganus fuscescens, which comprised about $83\% in number and about $73\%$ of the total catch. The diversity index of the number of species and information indices for individual and catch were the highest in October and the lowest in Septemer, indicating a close relationship with the change between the species number and catch at that time. A cluster analysis of 17 species was illustrated from the similarity matrix. All of the 17 species were grouped at the 0.2 similarity level. Three groups were present at 0.60 level, whereas species in other groups were sporadic in occurrence.

• Journal of Astronomy and Space Sciences
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• v.22 no.4
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• pp.393-408
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• 2005

We developed and compared two automatic algorithms for moving object detections in the YSTAR-NEOPAT sky survey program. One method, called starlist comparison method, is to identify moving object candidates by comparing the photometry data tables from successive images. Another method, called image subtraction method, is to identify the candidates by subtracting one image from another which isolates sources moving against background stars. The efficiency and accuracy of these algorithms have been tested using actual survey data from the YSTAR-NEOPAT telescope system. For the detected candidates, we performed eyeball inspection of animated images to confirm validity of asteroid detections. Main conclusions include followings. First, the optical distortion in the YSTAR-NEOPAT wide-field images can be properly corrected by comparison with USNO-B1.0 catalog and the astrometric accuracy can be preserved at around 1.5 arcsec. Secondly, image subtraction provides more robust and accurate detection of moving objects. For two different thresholds of 2.0 and $4.0\sigma$, image subtraction method uncovered 34 and 12 candidates and most of them are confirmed to be real. Starlist comparison method detected many more candidates, 60 and 6 for each threshold level, but nearly half of them turned out to be false detections.

• Tuberculosis and Respiratory Diseases
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• v.53 no.2
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• pp.173-182
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• 2002

Background : Nontuberculous mycobacteria (NTM) have usually been considered to be contaminants of colonizers when isolated from respiratory specimens in Korea, where there is a high prevalence of tuberculosis and a low rate of HIV infections. Therefore, there has been few studies on the clinical significance of NTM species in immunocompetent patients were investigated. Methods : Thirty-five NTM isolates, for which species identification was requested by the treating physicians during 1999 at the Asan Medical Center, were retrospectively analyzed. They were identified to the species level by mycolic acid analysis using high-performance liquid chromatography. The medical records of the patients with the NTM isolates were reviewed to identify those patients who met the American Thoracic Society (ATS)'s criteria for mycobacterial pulmonary infection. Their antimicrobial susceptibility data were compared with the clinical outcomes. Results : The NTM were identified as M. intracellulare (6 isolates), M. avium (5), M. abscessus (5), M. gordonae (5), M. terrae complex (4), M. szulgai (2), M. kansasii (2), M. fortuitum (2), M. peregrinum (1), M. mucogenicum (1), M. celatum (1), and M. chelonae (1). All 35 patients showed clinical symptoms and signs of chronic lung disease, but none had a HIV infections; 16 (45.7%) patients were found to be compatible with a NTM pulmonary infection according to the ATS criteria, 5 and 4 cases were affected with M. intracellulare and M. abscessus, respectively; 8 patients had a history of pulmonary tuberculosis. 13 patients received antimycobacterial therapy for an average of 21 months and 9 patients were treated with second-line drugs. Only 4 patients had improved radiologically. Conclusion : A NTM should be considered a potential pathogen of pulmonary infections in immunocompetent patients with chronic pulmonary diseases. Most NTM infections were left untreated for a prolonged period and showed a poor outcome as a result, M. intracellulare and M. abscessus were the two most frequent causes of NTM pulmonary infections in this study. Species identification and antimycobacterial susceptibility tests based on the species are needed for the optimum management of a NTM pulmonary infection in patients.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.95-100
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• 2012

This study was determined to analysis marine environmental and phytoplankton monitoring in Wando coastal waters in August during the period of 2009-2010 and provided the basic environmental data against Southwest Sea of Korea. In August, 2009, the distribution of water temperature and salinity showed an unique characteristics for all of stations, which was associated with a long duration of rainfall after July, 2009 and a lack of sunshine. In the lower of August, 2010, the stratification of water temperature and salinity was shown, which was caused by an intensive sunshine after the middle of August, 2010. Gangjin Bay and Gogeundo waters showed a highly different water temperature and transparency. It is thought that two regions have a distinct water mass and characteristics. In dissolved oxygen and oxygen saturation were higher according to higher water depth regardless of stations. In August, 2009, different dominant species occurred that Gangjin Bay showed a higher cell density of diatom, but Gonyaulax polygramma played an important role in dominant species in Gogeundo waters. It is associated with the introduction red tide water of G. polygramma occurring to southern coastal water in August, 2009. In August, 2010, diatom was extremely higher cell density compared with that of dinoflagellate that regarded as adaptive microrganism against higher quantity of suspended solid in Wando waters. Although Wando has a record of Cochlodinium red tide, this species may be difficult to grow and persist. Dominant species, diatom, play an important role in food organism for shellfish and forming a ecological lineage.

• Korean Journal of Heritage: History & Science
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• v.52 no.3
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• pp.112-129
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• 2019

This study investigates the influence and implications of the supervised process of production of flower vessels (花器) in 1411. The type, the production method, and the purpose of flower vessels (花器) were determined based on the workshops appearing in King Sejong-Sillok, Chiriji ("世宗實錄" "地理志") and Gyeongsang-do Chiriji ("慶尙道地理志"), considering articles excavated from Sangju kiln sites. In addition, the implications and the starting point of production of flower vessels (花器) in the Joseon Dynasty were identified. During the Joseon Dynasty, an effort was made to reorganize the government offices, to align ritual systems in the early 15th century. Preparation for rituals, preparation of supplemental utensils used in ancestral rites (祭器), the construction of architecture related to the Royal Family, and the production of weaponry (武器) were supervised. In 1411, flower vessels (花器) had a preferred supervised process of production as well, which means being recognized as a subject of maintenance for the Joseon Dynasty's aims. Flower vessels (花器) had been produced using grayish-blue powdered celadon (粉靑沙器) as flower pots (花盆), and as celadon flower pot-support (花臺), at Sangju kiln sites in particular, since 1411. Interestingly, products had been manufactured in royal kilns as well as in a few other kilns similar to the supervised process of production of flower vessels (花器) in the middle of the 15th century. It means that this effected the Gyeon-yang (見樣) supervised process of flower vessel (花器) production in 1411. At that time, the Joseon Dynasty used Gyeon-yang (見樣) for imperial gifts for the Ming Dynasty and on separate manufactured articles to ensure the standards of production. Gyeon-yang (見樣) affected the production of ceramic utensils used in ancestral rites (祭器), and government officials in Saongwon (司饔院) supervised the production of ceramics for the Royal Family year after year. In sum, it was flower vessels (花器) using Gyeon-yang (見樣) that provided precise production rules to supervise the process of production in 1411.

• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.35-48
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• 2021

In this study, the assessment of field applicability of in-situ remediation of nitrate-contaminated groundwater located in Yesan-gun was performed. Zero-valent iron/bio composite media injected PRB (Permeable Reactive Barrier) and monitoring well were installed in the contaminated groundwater site and monitored main remediation indicators during the PRB operation. Nitrate, nitrite, ammonia, Fe ion, TOC, and turbidity were analyzed and the diversity and population of microorganism in the PRB installed site were investigated for the verification of effect of injected PRB. In the study site where is an agricultural area, a river flows from west to east that forms a river boundary and the southern area has an impermeable sector. It was found that nitrate flows into the river, which is similar as groundwater flow. Simulation result for the fate of nitrate in groundwater showed steady state of nitrate arrived after 3~5 years passed. However, it is just to consider current conditions with no additional input of contaminant source, if additional input of contaminant source occurs contamination dispersion and time for steady state are expected to be increased. The monitoring results showed that Fe ion, TOC and turbidity in groundwater were not clearly changed in concentration after PRB installation, which indicates adaptability of the injected PRB for remediation of groundwater with no additional harmful effect to water quality. The concentration of nitrate maintained less than 5mg/L until 42 days after PRB installation and recovered its initial concentration after 84 days passed and showed termination of reactivity of injected zero-valent iron/bio composite media for removal nitrate. Nitrite and ammonia ions found after installation of PRB indicates reductive removal of nitrate. And the outstanding increase of microorganism diversity and population of Betaproteobacteria Class which includes denitrification microorganism explains biologically reductive removal of nitrate in injected PRB.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.125-132
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• 2007

We estimated the distribution of predator-prey interaction strengths for 12 species of herbivores (including amphipods, isopods, gastropods, and sea urchins) and made a regression model that may be applicable to other species. Laboratory experiments were used to determine per capita grazing rate (PCGR; g seaweeds/individual/day). Relationship between the biomass of individual grazers and fourth-root transformed PCGR was fitted to power curve ($y=0.2310x^{0.3290}$, r=0.8864). This finding supported that the grazing efficiency was not even as individual grazers increase in size (biomass). Therefore, the biomass-normalized PCGR was estimated and revealed that smaller size herbivores were more effective grazers. Grazing impact considering density of each taxon was calculated. The sea hare Aplysia kurodai had greatest grazing impact on the seaweed bed and the sea urchin Strongylocentrotus nudus and S. intermedius were ranked in descending order of the impact. The amount of seaweed grazed by the amphipod Elasmopus sp. (>4,000 $ind./m^2$) and Jassa falcata (>2,000 $ind./m^2$) were 3.435 and $1.697mg/m^2/day$ respectively. The combined grazing amount of herbivores was $5,045mg/m^2/day$ in the seaweed bed. Although sea hare and sea urchin had strong impacts on seaweeds, the effects of dense, smaller species could not be seen as negligible. Surprisingly, the calculated grazing potential of sea urchins with a mean density of 3 $ind./m^2$ exceeded the mean production of seaweed cultured in domestic coastal waters in Korea (ca., 5 ton/ha). Small crustaceans were also expected to consume up to 16% of the seaweed production if their densities were rising under weak predation conditions. Considering that the population density of herbivores are strongly controlled by fish, human interference like overfishing may have strong negative effects on persistence of seaweeds communities.

• Progress in Medical Physics
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• v.22 no.1
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• pp.42-51
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• 2011

Nuclear medicine images (SPECT, PET) were widely used tool for assessment of myocardial viability and perfusion. However it had difficult to define accurate myocardial infarct region. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using polar map with adaptive threshold. Rat myocardial infarction model was induced by ligation of the left circumflex artery. PET images were obtained after intravenous injection of 37 MBq $^{18}F$-FDG. After 60 min uptake, each animal was scanned for 20 min with ECG gating. PET data were reconstructed using ordered subset expectation maximization (OSEM) 2D. To automatically make the myocardial contour and generate polar map, we used QGS software (Cedars-Sinai Medical Center). The reference infarct size was defined by infarction area percentage of the total left myocardium using TTC staining. We used three threshold methods (predefined threshold, Otsu and Multi Gaussian mixture model; MGMM). Predefined threshold method was commonly used in other studies. We applied threshold value form 10% to 90% in step of 10%. Otsu algorithm calculated threshold with the maximum between class variance. MGMM method estimated the distribution of image intensity using multiple Gaussian mixture models (MGMM2, ${\cdots}$ MGMM5) and calculated adaptive threshold. The infarct size in polar map was calculated as the percentage of lower threshold area in polar map from the total polar map area. The measured infarct size using different threshold methods was evaluated by comparison with reference infarct size. The mean difference between with polar map defect size by predefined thresholds (20%, 30%, and 40%) and reference infarct size were $7.04{\pm}3.44%$, $3.87{\pm}2.09%$ and $2.15{\pm}2.07%$, respectively. Otsu verse reference infarct size was $3.56{\pm}4.16%$. MGMM methods verse reference infarct size was $2.29{\pm}1.94%$. The predefined threshold (30%) showed the smallest mean difference with reference infarct size. However, MGMM was more accurate than predefined threshold in under 10% reference infarct size case (MGMM: 0.006%, predefined threshold: 0.59%). In this study, we was to evaluate myocardial infarct size in polar map using multiple Gaussian mixture model. MGMM method was provide adaptive threshold in each subject and will be a useful for automatic measurement of infarct size.