• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.111-120
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• 2003

To describe dinoflagellate cysts from Gwangyang Bay, surface sediment samples were collected at 20 sites by the TFO core sampler on 24 August 2001, in coupled with a phytoplankton investigation by surface seawater sampling. More than 17 genera, 36 species of dinoflagellate cysts were Identified from the sediment samples of Gwangyang Bay, consisting of 14 species of gonyaulacoid, 14 species of protoperidinioid, 3 species of diplopsalid, 2 species of gymnodinioid, 1 species of tuberculodinioid and calciodinellid, respectively. Cyst concentrations in Gwangyang Bay varied from 115 to 2,188 cysts/g, and generally increased toward a western part of the study area. The highest cyst concentration was observed at St. 11 located in the northwestern region with 11 genera and 19 species(2,188 cysts/g), while the lowest value with 6 genera and 9 species(115 cysts/g) was observed at St. 3 located in the center of the study area. The predominant dinoflagellate cyst was Spiniferites bulloideus, followed by Alexandrium sp., Brigantedinium simplex and S. delicatus. The motile forms of eight dinoflagellate cysts recorded in the sediment samples were also observed in the seawater: Polykrikos swartzii/kofoidii complex, Scripssiella trochoidea, Protoperidinium claudicans(cyst name: Votadinium spinosum), P. pentagonum(: Trinovantedinium capitatum capitatum), P. conicum(: Selenopemphix quanta), P. leonis(: Quinquecuspis concretum), P. conicoides(: Brigantedinium simplex), Gonyaulax spp.(: Spiniferites spp.). In this study, heterotrophic dinoflagellate cysts show the highest concentration at St. 6 where the highest density of diatoms simultaneously observed from surface water sample. This result suggests that the grazing of heterotrophic dinoflagellates on the diatoms in high concentration caused the higher concentration of heterotrophic dinoflagellate cysts.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.4
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• pp.267-285
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• 2002

Dok Island, a Pliocene volcano, lies in the southwestern part of the East Sea. Most the work to date have focused primarily on the petrolography of the island, and as a result, the morphological characteristics and internal structure of the volcanic edifices of the Dok Island remain poorly understood. To provide better constraints on these features, bathymetric data with multibeam echo sounder, 32-channel seismic and 3D gravity modeling were used in this study. Three positive topographic highs are present in the study area, and these highs satisfy the seamount criteria. They are named as Dokdo, Tamhae, and Donghae seamounts. 32-channel seismic survey was conducted to investigate the sediment thickness of the area, which shows that there are no sediments near the summit of seamounts. Away from the seamounts, however, sediment becomes thick(>2000 m) toward the western part of the study area, and sediments in the northern and southern parts are about 1000 m thick. Free-Air gravity anomalies in this study generally follow the bathymetric feature with less than -20 mGal at the western part, but increase towards the seamounts. In the summit of the Dokdo Seamount, anomalies reach over 120 mGal, and in Tamhae and Donghae seamounts, the peak anomaly shows 90 and 70 mGals, respectively. All seamounts have an isolated volcanic conduit in their centre and show regional compensation root with 0.5～1.5 km thickness. The flat-topped summit of the seamounts is probably caused by wave truncation, indicating the sea level at the time of formation of the flat-topped geometry. Comparison between the present-day sea level and subsidence level during the opening of the East Sea suggests that the seamounts in the study area have subsided by 200～300 m after the formation. Furthermore, it implies that the seamounts formed over 12～10 Ma.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.95-107
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• 2015

In order to identify long-term trends of water quality parameters in Lake Kyeongpo, Mann-Kendall test, Sen's slope estimator and linear regression were applied on data, with 15 parameters from three different sites and rainfall, monitored once in every two months from March to November during 1998~2013. Seasonal variation analysis only used Mann-Kendall test and Sen's slope estimator. Analysis result showed that salinity, transparency and nutrient variables (total phosphorus, dissolved inorganic phosphorus, total nitrogen, nitrate nitrogen, ammonia nitrogen) were only parameters having statistically significant trend. In linear regression analysis, salinity (surface and bottom layer of all sites) and transparency (only at site 1), were figured out with statistically significant increasing trend, while in non-parametric statistical method, salinity and transparency in all sites (surface, middle, deep) were figured out with statistically significant increasing trend. Water quality parameters showing statistically significant decreasing trends were dissolved oxygen (surface layer of site 1 and bottom layer of sites 2 and 3), total phosphorus (sites 1 and 2), dissolved inorganic phosphorus, total nitrogen, nitrate nitrogen and ammonia nitrogen in the linear regression analysis and, dissolved oxygen (bottom layer of all sites), total phosphorus, dissolved inorganic phosphorus, total nitrogen, nitrate nitrogen and ammonia nitrogen in the non-parametric method. Seasonal trend analysis result showed that salinity, turbidity, transparency and suspended solids in spring, salinity, transparency, nitrate nitrogen and suspended solids in summer and temperature, salinity, transparency and suspended solids in fall were the variables depending on the season with increasing trends. In general, rainfall during the research period showed decreasing trend. The significant reduction trends of nutrients in Lake Kyeongpo were believed to be related to lagoon restoration and water management project run by Gangneung city and under-water wear removal, but further detailed studies are needed to know the exact causes.

• Journal of Animal Environmental Science
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• v.16 no.1
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• pp.41-50
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• 2010

The goal of this study was to develop a suitable ventilation system for high-rise hog building (HRHB) for growing-fattening with combined slatted floor pen in second story and in situ manure management system in Korea. The HRHB was constructed as 29m long, 9m wide and 7.6m high for outer dimension with an indoor height of 3.1m and 2.4 for lower and upper floor, respectively. Ventilation systems for each treatment were installed in separated rooms of HRHB. The ventilation types installed in each room were following 3 types: ventilation type 1 (V1), where air was pulled through a circular duct inlet and exhausted by fans; ventilation type 2 (V2), where air was pulled through eave inlet (side ceiling inlet) and exhausted by fans; and ventilation type 3 (V3), where air was pulled through baffled ceiling inlet and exhausted by fans. For each ventilation system, investigated air velocity under minimum, medium and maximum ventilation ratio and air flow pattern inside. The results were as follows; For air flow pattern from top to bottom, V1 showed a homogeneous vertical type, V2 showed a bilateral symmetry type and V3 showed an vertical umbrella type. Under minimum ventilation ratio, air velocity in upper floor (80cm above the slated floor) was similar for V1, V2, and V3. Under maximum ventilation ratio, air velocity in upper floor was undeviating for V1 (0.10~0.26m/s) and varied for V2 (0.12~0.63m/s) while those for V3 was relatively slow and less varied (0.07~0.15m/s). In conclusion, Duct inlet type (V1) can be applied to the development of a new HRHB with additional evaluations such as field test hog feeding.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.2
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• pp.132-139
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• 1995

This experiment was canied out to select the soybean of high productivity suited for soiling. and growth characterisitcs, palatability, dry matter and crude protein yield of 10 cultivars of soybean have been evaluated at the experimental forage field. College of Natural Science of Kon-Kuk University in Chungju over three years (1 989-1 09 1 ). The results obtained are summarized as follows: JangBaek showed the tallest plant length from the 70th day to 80th day during cultivation period. and BaekUn showed the tallest at 90th day. PalDal among all cultivars showed the fastest growth rate and the strongest resistant lodging during cultivation period. The stem diameter of 70th day showed highly in order of PalDal and HwangKeum > BaekUn > KwangKyo and JangYeob, the 80th day showed highly in the order of TogYu > BaekCheon > JangBaek and 90th day showed highly in order of BangSa > BaekCheon > JangYeob. Stem hardness was highly increased with increasing of cultivation period, but no significant difference were found among the soybean cultivan. Especially, BaekUn and TogYu of 90th day showed very high as 17.9 and 17.6 kg/cm2, respectively. In the number of branch, PalDal was the lowest during cultivation period(70, 80 and 90th day), and 90th day showed lower two and three times than other soybeans(P<0.05). In the leaf rate, BaekCheon showed the highest according to cultivation period and the lowest in JangBaek. The fresh yield was tended to increase by increasing cultivation period at all cultivars except KwangKyo, but no significant differences were found among cultivars. Dry matter yield of JangYeob was the highest as 5, 861 kg/ ha at 70th day, and that of KwangKyo and TogYu was the highest as 7, 471 and 10, 603 kgha at 80th and 90th day, respectively. Relative palatability of 70th days showed very high at all soybean cultivars(81-100%), and that of 80th and 90th day showed the highest at TogYu, while showed the lowest at PalDal. In crude protein content of the 70th, 80th and 90th day, DanYeob, JangYeob and HwangKeum were the highest as 20.1, 17.9 and 20.4 percentage, respectively. Crude protein yield during cultivation period showed the highest at JangYeob(7Oth : 1, 068, 80th : 1, 211, 90th : 1, 882 kglha), but showed the lowest at BangSa(70th : 61 1, 80th : 814, 90th : 1, 078 kg/ha).

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.1
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• pp.21-25
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• 2014

Singwangok, a new single cross variety, was developed by the maize breeding team at the National Institute of Crop Science (NICS), RDA in 2012. This hybrid, consisting of a high yield of grain, was produced by crossing two inbred lines, KS172 and KS173. KS172 is the seed parent and KS173 is the pollen parent of Singwangok. It is a yellow-orange intermediate maize hybrid (Zea mays L.). After the preliminary yield trial and advanced yield trial of Singwangok (Suwon185) in Suwon for 2 years, the regional yield trial of that was subsequently carried out for its growth characteristics and yield at 3 different locations from 2010 to 2012. It was named as Singwangok. The silking date of Singwangok is similar to the check hybrid, Jangdaok. The plant height of Singwangok is similar to Jangdaok, but its ear height ratio is lower than that of Jangdaok. Moreover, it has a resistance to lodging. The ear number per 100 plants of Singwangok is more 17 than that of Jangdaok, whereas the ear length of Singwangok is similar to Jangdaok. Further, the weight of 100 seeds of Singwangok is similar to Jangdaok. It has a moderate resistance to southern leaf blight (Bipolaris maydis) and a strong resistance to northern leaf blight (Exserohilum turcicum). Furthermore, it has a moderate resistance to the black streaked dwarf virus (BSDV), ear lot and corn borer. The grain yield of Singwangok, 7.81 ton/ha, was similar to that of Jangdaok. The seed production of Singwangok was well processed due to the good match during crossing between the seed parent, KS172 and the pollen parent, KS173, in Yeongwol; the F1 seed yield was 3.84ton/ha. Singwangok would be a suitable cultivar to all plain areas in Korea.

• Korean Journal of Food Science and Technology
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• v.50 no.3
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• pp.331-338
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• 2018

The purpose of this study was to determine the optimum sterilization conditions for the production of retorted steamed egg using response surface methodology. Sterilization processes for eighteen conditions using varying sterilization temperature ($X_1$), time ($X_2$), and method ($X_3$) as the independent variables were carried out through a $3^2{\times}2$ experimental factorial design. Quality evaluations after sterilization included measurements of $F_0$ value ($Y_1$), peak stress ($Y_2$), pH ($Y_3$), color value ($Y_{4-6}$), and organoleptic test [preference for appearance ($Y_7$), overall acceptability ($Y_8$), and preference for texture ($Y_9$) and egg taste ($Y_{10}$)]. Dependent variables ($Y_{1-10}$) of eighteen conditions were more affected by temperature and time than by the sterilization method. Eight factors were selected among the dependent variables as significant factors related to the quality of the steamed egg. Finally, by establishing an optimum range of each dependent variable and contour analysis, the optimum sterilization conditions for the production of steamed egg were determined to be $120^{\circ}C$ for 25 min using a 2-step sterilization process.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.461-471
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• 2016

This study was conducted to establish an in vitro propagation system for sea-milkwort (Glaux maritima L.), which is an endangered coastal plant species with high horticultural value. Two phenotypes, 'Red type (RT)' and 'Pistachio type (PT)' based on the colors of stem and flower, were obtained from a personal horticulturist in 2009 and used for this study as plant materials. The stock plants showed typical morphologies in flower, capsule, and seed appearances as previously reported. Low temperature treatment at $4^{\circ}C$ for four or more weeks after in vitro sowing maximized seed germination percentage, indicating that imbibition of seed and subsequent low temperature treatment are crucial for its germination. The in vitro seedlings had phenotypic variation, falling into 'RT' and 'PT' classes like the stock plants. Although slight differences depending on genotype and medium were recognized, the fourth or fifth nodes detached from the in vitro seedlings revealed the best multiplication efficacy when estimated on the basis of total number of nodes of newly developed axillary shoots. In addition, the nodes from 'RT' and 'PT' regenerated the most shoots on medium supplemented with $0.5mg{\cdot}L^{-1}$ BA alone and $0.5mg{\cdot}L^{-1}$ BA plus $0.5mg{\cdot}L^{-1}$ IAA, respectively. The node culture-derived plantlets were well acclimatized in a culture room ex vitro and completed the pseudo-annual life cycle coincident with that in the natural salt march habitat with the current cultivation method of applying fresh water-irrigation under an inland environment. This work represents the first report of in vitro propagation of sea-milkwort. Thus, our study will contribute to exo-habitat conservation and natural habitat restoration of this endangered species in addition to development of a horticultural product.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.2
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• pp.99-104
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• 2006

Human Papilloma viruses (HPVs) are etiological agents for cervical cancer and are classified into low- and high-risk categories. The aim of this study was to determine the frequency of the HPV genotype in the HPV screening test of Korean women using PCR-direct sequencing. Consensus primers of L1 legion were used for the amplification of HPV DNA and the PCR products (450 bps) obtained were analyzed by automatic sequencing. Sequences were compared with those in GenBank by using the BLAST program. Cervical swab samples of 3,978 women (20-73 years) were tested and the average age was 37.6 years. In this study, 1,174 samples were HPV positive out of 3,978 cervical swab samples screened (29.5%) and 136 samples (11.6%) showed a double infection. A total of 1,310 HPV genotypes were analyzed. The HPV positive rate was the lowest in the 20 years group (69.5%) and most of the samples of the > 60 years group were found HPV positive. Among thirty seven different HPV types identified by sequencing, 21 were HPV high risk types and 16 HPV low risk types were 69.8% (914/1,310) and 26.0% (340/1,310), respectively. In HPV high-risk types, 16 (13.21%), was the most frequently found. HPV 53 (9.62%) and 58 (9.24%) were also frequently found. This group was followed by HPV types 70 (5.50%), 33 (4.73%), 66 (4.20%), 18 (4.05%), 52 (4.05%), 31 (3.97%) and 56 (3.51%) in descending order of frequency. Among HPV low-risk types, 62 (4.20%), 6 (3.59%), 81 (3.59%), 84 (3.51%), and 11 (2.6%) were frequently found. In conclusion, PCR-direct sequencing could be used for quick and reliable typing of known and novel HPVs from clinical specimens. This data could be useful for epidemiological study of HPV and it also allows type-specific follow-up of women who have been treated for cervical intraepithelial neoplasia.

• Journal of Food Hygiene and Safety
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• v.32 no.6
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• pp.477-484
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• 2017

This study was conducted to investigate the content of sulfur dioxide, carotenoids and the degree of contamination of Bacillus cereus in 33 kinds of dried sweet potato from domestic mainly dried agricultural products in Korea. According to the characteristics of dried sweet potato samples, it was classified into four clusters and as a result of analyzing the contents of sulfur dioxide, carotenoids and the degree of contamination B. cereus was no significant difference among the clusters. The detection ranges of residual sulfur dioxide from 33 dried sweet potatoes ranged from 0.38 to 28.16 mg/kg, three cases (9.09%) were detected at the reference level of 10 mg/kg or more. But no samples exceeding 30 mg/kg, the tolerance level of sulfur dioxide in dried sweet potatoes were detected. Since dried sweet potato does not have a standard for carotenoids, when comparing the national and international standards of carotenoids, the range of detection of carotenoids in dried sweet potato was $46{\sim}2,663{\mu}g$/100 g, which was within the reference range of $0{\sim}9,826{\mu}g$/100 g. In principle colonies suspected to be B. cereus in dried sweet potato were not detected. In 7 cases (21.21%), there were detected in the range of 0.05~1.59 log CFU/g but not more than 3 log CFU/g as the reference value. The results of this study are expected to be used as basic data to establish quality standard for dried sweet potatoes. In order to control the quality of dried sweet potatoes in domestic market, raw materials, drying method and packaging after distribution, it is necessary to maintain and maintain the process steadily.