• 한국데이터정보과학회:학술대회논문집
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• 2003.05a
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• pp.145-158
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• 2003

불완전 데이터 즉, 결측값을 가지는 데이터를 분석할 경우 결측데이터에 대해서 어떠한 처리를 해야할 필요가 있다. 결측데이터에 대한 처리로서 주로 이용되어온 방법으로는 결측값을 포함한 관측값(case)을 제외하는 방법이었다. 이후 여러 방법들이 제안되어 EM알고리즘이나 회귀알고리즘에 의한 추정을 바탕으로 결측값에 대한 추정을 해서 그 추정값으로 결측값을 대치하는 방법을 사용할 수 있게되었다. 본 논문에서는 복수 개의 데이터세트를 생성해서 대치하는 다중대입 소프트인 SOLAS를 소개한다.

• Food Science and Preservation
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• v.17 no.1
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• pp.23-29
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• 2010

The effects of vinegar, alcohol, and vitamin C on the color, microorganism count, volatile flavor components, free sugar level, free amino acid concentration, and free fatty acid level of minced ginger were investigated during storage for 17 weeks at $10^{\circ}C,\;20^{\circ}C\;or\;30^{\circ}C$. Bacterial levels remained unchanged during storage and mold was not initially detected. Yeast levels in minced ginger were $5{\times}10^1$ CFU/g initially, and yeast was not detected after 2 weeks. The color values increased during storage at high temperature. The volatile flavor component levels decreased during high-temperature storage. The free sugars of minced ginger were glucose, sucrose, and fructose. Sugar levels did not vary greatly with storage temperature. Free amino acid content decreased during high-temperature storage, and glutamine, valine, alanine, asparagine, tyrosine, and leucine were detected. Free fatty acid content increased during storage and the ratio of unsaturated to saturated fatty acids was 3:7.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.59-64
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• 2010

The effects of vinegar, alcohol and ascorbic acid on the color, microorganism, sensory properties and flavor pattern of minced ginger (MG) were investigated during storage for 28 days at $30^{\circ}C$. The values of L (lightness), a (redness) and b (yellowness) of the control (T-0) and all the treatments changed slightly at the initial stage of storage, however the elapse of time accelerated the changes. The total bacterial counts of T-0 showed $5.37{\times}10^7\;CFU/g$ at the initial stage, but the MG-treatments decreased the bacteria above 4 log compared to T-0. It was showed that the additives were effective for inhibition of the growth of microorganism. Sensory properties of flavor intensity test showed no significant difference between T-0 and MG-treatments (p < 0.05). The result of volatile flavor contents of electronic nose analyzer (ENZ) showed that MG-treatments (T-I, T-II, T-III) was recognized stronger than non-treatment at the initial stage, but the change of flavor compound were stabilized soon regardless of type or quantity of additives during total storage period at $30^{\circ}C$.

• Korean Journal of Environment and Ecology
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• v.14 no.3
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• pp.167-174
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• 2000

거제도 남동 해안지역의 한려해상국립공원 보호구역에서 해상자원의 보존을 위한 기초자료를 확보하고자 거제도 일운면 예구리, 남부면 다대리 및 남부면 저구리 해얀지역에서 1999년 6월부터 2000년 3월까지 어류상 조사를 실시하였다. 조사를 통하여 확인된 어류는 총 16목 47목 69속 85 종 2, 789개체가 채집되었으며, 45종이 출현한 농어목(Perciformes), 10종씩 출현한 가자미목 (Pleuronectiformes) 및 횟대목(Scorpaseniformes)의대부분 저서생활을 하는 어류가 주로 채집되었다. 전체 조사기간 동안 가장 만하은 개체가수가 채집된 어류를 줄비늘치(Coelorhyncus multispinulosus) 458개체(16.4%)로 확인되었고 칠서대(Cynoglossus interruptus) 384개채(13.8%), 노랑촉수(Upeneus bensasi) 285개체(10.2%) 등의 순 이었다. 조사시간 6월에 가장 다양하고 풍부한 어류가 채집되었다.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.186-192
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• 2005

We investigated the deposition characteristics and mass transport flux estimation of the Nakdong estuary, Korea. To understand the effects of the tidal current circulation that influences estuary terrain changes, we used a 2D numerical model to map seawater circulation under three different situations, with the level of river flow being set as none or flood. The net-water flux of the cross-sectional area between sandbars (known as dung) was estimated. From our review of previous research, we know that the development of local sandbars shifted from the west to the east side of the estuary after the construction of the Nakdong River dike. Current development is occurring mostly at the Bakhap-dung near Tadea. The seawater circulation pattern over this large-scale area of tidal na is brings changes related to the quantity of the outflow from the Nakdong River. Based on the calculated results for the net-water flux of the cross-sectional area, we see very strong accumulation in local waters around Jangjiado, Bakhapdung, and Tadae under flood river flow conditions, but accumulation in local waters around Jinudo under the other states of flow. Consequently, in the Nakdong estuary, the main sensitive regions that are affected by changes in the flow of river discharge are the local waters around Jangiado, Bakhapdung, Tadae, and Jinudo.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.2
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• pp.288-293
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• 2022

Recently, metaverse is becoming increasingly important in coding education. One of the most important elements in metaverse is interaction in 3D virtual space. However, most existing education methods still utilize metaverse for unidirectional education without making use of interaction. This paper proposes a new method of using metaverse for bidirectional coding education. In the metaverse virtual space, a professor and students are able to share their PC screens for monitoring purposes. Also, once a student sends a request to the professor, the professor can immediately provide proper feedback (such as source codes correction) through access control. This metaverse virtual space is able to include more than two professors that allows for a many-to-many coding education. This paper presents a way of constructing the metaverse environment and teaching scenario, followed by the descriptions of the advantages and requirements for the proposed method.

• Korean Journal of Microbiology
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• v.32 no.3
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• pp.238-244
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• 1994

To investigate the bacterial potentials for utilizing dissolved organic matter in highly eutrophic estuary, the annual fluctuations of microbiological and physicochemical environmental parameters were analyzed in Naktong River Estuary. Total bacterial number ranged from 0.33 to $2.09{\times}10^7$ cells/ml, and correlated with the heterotrophic bacterial numbers in more eutrophic sites, especially. Bacterial biovolume and biomass varied between 0.064 and 0.156 2.09${\mu}m^3$/cell, 0.163 and 1.036 ${\mu}g$-C/ml, respectively. Bacterial secondary productivity ranged from 0.24 to 60.86 ${\mu}g$-C/l/h, and showed high correlations with the environmental parameters of pollution indicator. The seasonal variation pattern of bacterial productivity in freshwater sites was high in winter and low in summer, which was interpreted as the results of pollution loads varied with the amount of rainfall. In seawater site, the pattern was different from those of freshwater sites; high in summer and low in winter. In this site, the values of bacterial productivity showed positive correaltions with chlorophyll a, heterotrophic bacterial number, and temperature (r>0.5, p<0.05). These results suggested that the main source of organic matter which influences the bacterial productivity may be allochthonous materials in the upper freshwater zone of Naktong River Barrage, and autochthonous algal excretory products in the lower seawater zone of Naktong River Barrage.

• Journal of Aquaculture
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• v.7 no.4
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• pp.251-264
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• 1994

To study the causes of occurring toxic dinoflagellate Alexandriwn species, an experiment was undertaken in Jinhae Bay shellfish harvesting areas. The water and sediment samples were collected to record the abundance of Alexandriwn species, and to study the distribution and the germinability of those benthic cysts from September 1993 to July 1994. Alexandrium species were began to appear at all the sample stations after January, and reached maximum concentration (530 cells/l) at Taekok station (Chilcheon-do) in March 1994. Alexandrium cysts were also found at every station surveyed, of which several sites showed the higher concentration of 700-800 $cysts/cm^3$ at the upper sediment profile (0-4cm), but the concentrations were wide range of 100-800 $cysts/cm^3$. The results of each sampling season showed a great difference in the cyst germination experiments, were potentially high in cold season; $72.5\%$ (Jan.), $68\%$ (Apr.),$44\%$(Jul.), and $9\%$ (Oct.). These results suggested that germination of Alexandrium resting cysts in 15 m depth of coastal waters in Jinhae Bay would be controlled by a seasonal endogenous clock instead of the general environmental factors like temperature. Therefore, it is possible that Alexandrium species could be abundant by the germination of resting cysts in cold season, and contribute to the regional paralytic shellfish poisoning (PSP) toxification.