• The Korean Journal of Ecology
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• v.6 no.1
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• pp.1-13
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• 1983

A survey was conducted on the vegetation of southern slope of Daecheong-bong, Mt. Seolag, Located at the northern part of Taebaek mountain chain in the Central Korea. The altitudinal zonation of the vegetation was analyzed by distribution pattern of dominant species along thermal gradient, In additiion to these procedure th plant sociological studies by Braun-Blanquet(1964) were carried out. It was recognized that the vegetation is consist of 16 associations including Quercus mongolica-Lindera obtusiloba. association and the forest zone is classified into southern, central and northern part of cool temperate forest and subarctic forest.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.1
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• pp.41-47
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• 1991

Air pollution potentials of the 7 cities in the central part of Korea were obtained with the mean wind speed within the mixed layer and the mixed layer height calculated by the Jump Model. Seasonal variation of the afternoon mixed layer height in Seoul area shows that low in winter and high in summer. Annual mean of the morning air pollution potential was lowest in Incheon and highest in Wonju. On the other hand annual mean of the afternoon air pollution potential was lowest in Incheon and highest in Chuncheon. Relatively low air pollution potential in Incheon can be explained as high mixed layer height and the effect of sea breeze.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.99-107
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• 1997

We consider a multiechelon repairable-item inventory system where several bases are supported by a central depot and the external repair facilities. Unlike METRIC- based models, there are only a finite number of repair channels at each base, central depot and the external repair facilities. It is desired to find repair capacities and spares level which together guarantee a specified service level at minimum cost. Closed queueing network theory is used to model the stochastic process. The purpose of this paper is to derive the steady-state distributions of this system.

• Journal of Environmental Health Sciences
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• v.46 no.5
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• pp.599-609
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• 2020

Objectives: Coronavirus disease 2019 (COVID-19) first emerged in December 2019 in Wuhan, China, and has rapidly become a global pandemic with over 26.4 million confirmed cases and approximately 871,000 fatalities worldwide as of this writing. In the Republic of Korea, disease clusters frequently occurred in long-term care hospitals where the majority of residents are elderly with underlying medical conditions. Despite the fact that public health authorities and local community health centers have put tremendous efforts into preventing the spread of disease, positive cases have continued to occur. Thus, the Korea Centers for Disease Control & Prevention rapid response team decided to conduct an environmental investigation of a long-term care hospital to identify whether environmental contamination has remained and contributed to the spread of COVID-19. Methods: An environmental investigation was conducted at Hospital A. The characteristics of the facility and its HVAC system were assessed by checking the layout and interviewing the people in charge. A total of 64 surface samples were collected from areas of concern, including patient rooms, toilets, elevators, and nurses' station. These samples were tested by a regional health and environmental research institute using real-time reverse transcription polymerase chain reaction. Results: All samples from Hospital A were confirmed to be negative. Through interviews with high-level personnel at the regional community health center, we found that extensive disinfection is frequently performed on potentially contaminated areas in Hospital A in accordance with government guidelines. Conclusion: The environmental control measures implemented in Hospital A had been sufficient for mitigating the risk of further infection, suggesting that such measures may also be effective for other long-term health care facilities.

• Journal of Microbiology and Biotechnology
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• v.17 no.4
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• pp.611-615
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• 2007

The purpose of this study was to evaluate the immunogenicity and safety of Salmonella Typhi Vi capsular polysaccharide vaccine (Vi vaccine) in Korea. The immunogenicity of a single dose of Vi vaccine was evaluated in 157 subjects (75 children and 82 adults) before and at 1, 6, and 12 months after vaccination. Immunogenicity was measured with a passive hemagglutination assay (PHA), quantified as geometric mean titers (GMTs) and seroconversion rates. The safety of the vaccine was investigated by determining adverse reactions occurring within 4h, 3 days, and 1 month after injection. The seroconversion rate for children and adults 1 month after vaccination was 96.92% and 89.02%, respectively. In the case of children, the GMTs of Vi antibodies before vaccination were $5.87{\pm}1.34\;and\;142.59{\pm}2.39$ at one month after vaccination. For adults, the GMTs before and one month after vaccination were $5.58{\pm}1.28\;and\;58.56{\pm}3.67$, respectively. Vi antibodies persisted for as long as 6 and 12 months after vaccination. All adverse reactions in adults and children were minor and did not require treatment. The Vi CPS vaccine was safe and immunogenic in adults and children older than 5 years.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.598-603
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• 2018

As basic research for optimal barley cultivars selection and technical development for quality maintenance, a total of 21 commercial malt products (for making 'Sikhye', a traditional Korean sweet drink) were collected from the Korean market. And then we analyzed the component of the barley malt products as well as conducted comparative analysis on enzyme activity and quality characteristics of the commercial barley malt products. Of the 21 barley malt products, 12 were made from 100 % barley. The result of analyzing general components of barley malts turned out different level of components; moisture 4.91~11.99%, lipid 1.71~2.48%, protein 7.80~11.97%, carbohydrate 73.64~82.24%, total starch 5.50~8.22%, reducing sugar 3.64~14.44%. As a result of measuring enzyme activity of barley malts, there was a wide range of activity difference by the product; diastatic power $36.80{\sim}94.30^{\circ}$, ${\alpha}$-amylase activity 18.17~186.50 unit/g, ${\beta}$-amylase activity 6.53~25.05 unit/g. The results of this study would be used as basic data for optimal cultivars selection to produce barley malts and technical development for quality maintenance.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.577-586
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• 2018

The proximate compositions, quality and physicochemical characteristics of mung-bean cultivars cultivated in the north-central region of South Korea with different seeding periods were evaluated. A significant difference was noted in the proximate compositions and chromaticity of mung-beans according to cultivars and different seeding periods. Crude ash and protein content decreased with the delay in seeding period and a slight increase in carbohydrate content was observed. Redness of the other five cultivars increased with the delay in seeding period except for the cultivar Jangan, while the yellowness decreased in cultivars Geumsung and Jangan. Water binding capacity of the $1^{st}$, $2^{nd}$ and $3^{rd}$ seeding on the cultivar Eoul was 115.15, 99.76 and 96.31%, respectively, and a decrease in the binding capacity was observed with the delay in seeding periods. Water solubility index and swelling power were significantly different among cultivars. Total polyphenol content of $1^{st}$ and $2^{nd}$ seeding on the cultivar Jangan was 8.59 and 8.57 mg GAE/g, respectively, and a decrease was observed with the delay in seeding periods except for the cultivar Sohyeon. Total flavonoid content of $1^{st}$ seeding on the cultivar Jangan was 5.25 mg CE/g, which decreased with the delay in seeding periods. DPPH radical scavenging activity of $1^{st}$ seeding on the cultivars Geumsung and Kyungseon was 2.44 and 2.32 mg TE/g, respectively, which decreased with the delay in seeding periods. The BTS radical scavenging activity of $1^{st}$ seeding on the cultivar Jangan was 6.98 mg TE/g. In the present study, the variations in phenol content and radical scavenging activity were observed to be dependent on the cultivars and seeding periods.

• The Korean Journal of Food And Nutrition
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• v.32 no.5
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• pp.425-433
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• 2019

Sikhye is a traditional rice beverage, produced from steamed rice, barley or wheat malt and water. Nine varieties of barley and seven varieties of wheat cultivars were investigated and compared quality characteristics, diastatic power, and activities of ${\alpha}$- and ${\beta}$-Amylase. For barley malt, the crude lipid and protein content of malt 1.74~2.42% and 10.71~14.36%, respectively. Also, the crude lipid and protein content for wheat malt 1.57~1.71% and 10.07~13.59%, respectively. The 'Dahyang' barley showed the highest diastatic power with $117.61^{\circ}L$, while for wheat, 'Baegjoong' produced the highest diastatic power with $85.25^{\circ}L$. The enzymatic activities, ${\alpha}$- and ${\beta}$-Amylase for barley cultivar was $110.17{\sim}214.70{\mu}nit/g$ and $869.73{\sim}1,638.43{\mu}nit/g$, respectively. Likewise, ${\alpha}$- and ${\beta}$-Amylase for wheat cultivar was $73.19{\sim}132.23{\mu}nit/g$ and $726.70{\sim}889.30{\mu}nit/g$, respectively. The highest sugar content of Sikhye from barley was $11.10^{\circ}Bx$ ('Hyeda'), while from wheat, was $10.20^{\circ}Bx$ ('Baegjoong'). Among the four free sugar components analyzed from Sikhye, maltose was the highest in all cultivars. The highest maltose content was produced in 'Dahyang' Sikhye at 6.91%. There was significant positive-correlation among the diastatic power and enzymatic activities of malt and free sugar components in Sikhye.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.792-801
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• 2018

Proximate compositions, quality and physicochemical characteristics of small black soybean cultivar, cultivated in the north-central region of South Korea with different seeding periods, were evaluated. Proximate compositions, chromaticity, water binding capacity, water solubility index, swelling power, and antioxidant properties were significantly different among cultivars and different seeding periods. Moisture, crude ash, fat, protein, and carbohydrate contents of small black soybean cultivar were 5.53~6.69, 5.47~6.54, 15.38~19.14, 34.17~40.26, and 32.04~36.85 g/100 g, respectively. Lightness, redness and yellowness were 35.60~38.61, -0.02~0.07 and -0.56~-0.13, and water binding capacity, water solubility index and swelling power were 84.48~148.31, 46.65~54.89 and 29.87~35.12%, respectively. Total polyphenol contents of first, second, and third seedings on small black soybean cultivar were 10.40~15.48, 9.86~14.85 and 8.61~15.39 mg GAE/g; total flavonoid contents were 5.81~7.25, 5.81~7.34 and 5.52~7.64 mg CE/g, respectively. DPPH radical scavenging activity was 4.55~7.86, 3.99~8.79, and 3.74~9.43 mg TE/g, and ABTS radical scavenging activity was 9.32~12.90, 8.64~13.39, and 8.51~14.35 mg TE/g, respectively. Phenol compound of Tawonkong and Socheong cultivars decreased with delay of seeding periods. Radical scavenging activity of Socheong and Jununi cultivars decreased with delay of seeding periods, but Socheong 2 and Socheongja cultivars increased. In the study, phenol compound and radical scavenging activity of small black soybean cultivar were different, depending on cultivars and seeding periods.

• Ocean and Polar Research
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• v.26 no.1
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• pp.33-42
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• 2004

Effect of freshwater discharge on the long-term salt balance in the Northern and Central Indian River Lagoon (IRL) is successfully simulated by a new analytical solution to a water balance-based one-dimensional salt conservation equation. Sensitivity tests show that the salinity levels drop abruptly even during the dry season (November to May) due to the high surface runoff discharge caused by tropical storms, depressions, and passage of cold fronts. Increasing surface runoff and direct precipitation has risen by ten times, lowering the salinity level down to 12psu in the Northern Central zone, and to 17 psu in the Northern zone. However, the salinity level in the Southern Central zone has decreased to 25 psu. High sensitivity of the Northern Central zone to freshwater discharge can be partially explained by a rapid urbanization in this zone. During the dry season, less sensitivity of the Southern Central zone to the increased surface runoff is attributed to the proximity of the zone to the Sebastian Inlet and a strong diffusion condition possibly resulting from the seawater intrusion to the surficial aquifer at the Vero Beach. During the wet season, however, the whole study area is highly sensitive to freshwater discharge due to the weak diffusion conditions. High sensitivity of the IRL to the given diffusion conditions guarantees that the fresh-water release occurs during strong wind conditions, achieving both flood control in the drainage basin and a proper salinity regime in the IRL.