• Journal of Conservation Science
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• v.32 no.4
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• pp.579-588
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• 2016

This study analyzed nonmetallic inclusions in iron swords with a ring pommel excavated in the Ipbuk-dong, Suwon. Scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS) was used to estimate the iron-making temperature, and we compared the oxide with $SiO_2$ to investigate the heat-treatment technology in the production of iron swords with a ring pommel by investigating the artificial insertion of a slag former and the metallurgical structure. From the wustite observed in most of the specimens, it is judged that these swords were produced by heating and forging iron smelted at a low temperature using the solid reduction method. In addition, judging from the partial presence of $P_2O_5$, it is assumed that they were smelted directly with natural ore, not calcined. From the ratios of $CaO/SiO_2$ and $TiO_2/SiO_2$, it is judged that the raw material for iron-making was iron ore and that a calcareous slag former was not artificially inserted. The structure of the blade part on the front end was pure iron. From the high carbon content of the blade part on the ring pommel and the formation of a martensitic structure and pearlite colony, it is judged that they were tempered after carburizing and that the back, handle part, and ring pommel were unintentionally carburized. Judging from the structure of these specimens, it was noted that they were produced by applying artificial partial heat-treatment technology. This study attempted to present a more scientific analysis by using the method of interpretation through component analysis of nonmetallic inclusions appearing in one relic by the ratio of the oxide divided by $SiO_2$. It is judged that reinterpreting the arguments by the results of the existing analysis and research in this way can obtain different interpretations.

• Applied Biological Chemistry
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• v.17 no.4
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• pp.247-256
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• 1974

The Merit variety of soybean (Glycine max L.), harvested in 1971 was germinated in the dark at $21{\sim}25^{\circ}C$ for 10 days. The soybean sprout were divided into cotyledons and seedling axis and subjected to the determination of lipoxygenase activity and fatty acid composition of triglycerides, free fatty acids, phosholipids and crude fat fractions at two-day intervals during the germination periods. The results are summarized as follows 1) The lipoxygenase activity in cotyledons declined sharply after second day, but the activity in seedling axis inclined slightly after second day. However, the decrease of lipoxygenase activity in cotyledons coincided with decrease of linoleic and linolenic acids in cotyledons and increase of lipoxygenase activity in seedling axis coincided with increase of those acids in seedling axis. 2) The iodine value of neutral fat in cotyledons decreased continuously, but the iodine value of the neutral fat in seedling axis remained almost constant. iodine value in cotyeldons was greater than in seedling axis. 3) In the fatty acid composition of triglycerides in cotyledons, palmitic acid did not changes significantly, stearic acid increased continuously, oleic acid changed irregularly, linoleic and linolenic acids continuously decreased significantly. But in the fatty acid composition of triglycerides in seedling axis, palmitic acid remained unchanged, linoleic and linolenic acids slightly increased continuously, stearic and oleic acids changed irregularly. 4) Composition of free fatty acids in cotyledons and seedling axis changed irregularly, suggesting that all fatty acids produced by hydrolysis of triglycerides by lipase are used(or either biosynthetic Purpose or energy Production at random. 5) Fatty acids with odd-numbered carbon chain were not detected in the triglycerides and free fatty acid fractions during the germination periods, suggesting that all fatty acids are utilized as $C_2$-unit in degradation and biosynthesis. 6) The changes of fatty acids composition of Phospholipid in cotyledons and seedling axis during the germination were similar to these of triglyceride fraction.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.31-43
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• 2014

This experiment evaluated the interaction effect of extreme heat diet(EHD), inverse lighting, and cool water on the growth performance of broiler chickens under extreme heat stress. There were 4 experimental groups (T1: EHD 1, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T2: EHD 2, 10:00-19:00 dark, 19:00-10:00 light, cold water $9^{\circ}C$; T3: EHD 1, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$; T4: EHD 2, 09:00-18:00 dark, 18:00-09:00 light, cold water $14^{\circ}C$), each group composed of 25 broilers and the experiment was repeated 3 times. EHD 1 contained soybean oil, molasses, methionine and lysine. EHD 2 contained all nutrients of EHD 1 and vitamin C additionally. As a result, T1 and T2 displayed higher body weight increase and diet intake compared to T3 and T4 (p<0.05). The weights of their liver and gizzard were similar but the weights of the thymus and bursa F were higher for T1 and T2 compared to that of T3 and T4 (p<0.05). It was observed that T1 and T2 displayed higher concentrations of blood triglyceride, total cholesterol, HDL-C and blood sugar compared to that of T3 and T4 but LDL-C level was higher for T3 and T4 compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher levels of immunity substances such as IgG, IgA and IgM compared to T3 and T4 but the blood level of corticosterone displayed to be lower for T1 and T2 compared to T3 and T4 (p<0.05). The T1 and T2 contained a higher amount of fecal lactobacillus compared to that of T3 and T4 but the T3 and T4 contained a higher amount of fecal E. coli, total aerobic bacteria, coliform bacteria compared to that of T1 and T2 (p<0.05). T1 and T2 displayed higher concentrations of cecal acetic acid, propionic acid and total short chain fatty acids compared to T3 and T4 but T3 and T4 displayed higher concentrations of butyric acid, isobutyric acid, valeric acid and isovaleric acid compared to T1 and T2 (p<0.05). These results have been observed that broiler chickens exposed to extreme heat stress with feeding EHD, inverse lighting and cold water would improve blood lipid, and elevate the production of immunity substance, beneficial microorganisms, and short chain fatty acids. This provision would also reduce the blood sugar consumption rate as energy sources and these effects will improve the growth performance of the broilers exposed to extreme heat.

• Journal of Veterinary Clinics
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• v.32 no.4
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• pp.295-300
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• 2015

The aim of the study was to assess the in vitro effect of 808-nm InGaAs diode laser on rabbit articular chondrocyte proliferation and sulphated glycosaminoglycan (sGAG) synthesis in alginate bead. Previous studies revealed either positive or negative stimulatory effects of laser on different types of cells. A 808-nm InGaAs diode laser at 1.0W power output was used to irradiate the rabbit chondrocytes in alginate beads with energy densities of $31J/cm^2$ (G 1) and $62J/cm^2$ (G 2) corresponding to the experimental groups for 10 seconds and 20 seconds, respectively at 24, 48, 72 and 96 hours after seeding. Control group was left untreated. MTT assay was performed at 1 week and 2 weeks after the $1^{st}$ laser irradiation in alginate beads. sGAG synthesis in alginate beads at 1 week and 2 weeks were determined by DMMB assay. Histological evaluation for cellular distribution and sGAG deposition around the cells were performed by alcian blue stain. MTT assay revealed no positive stimulatory effect in cell proliferation in alginate bead. DMMB assay results showed significantly increased sGAG production in G 2 chondrocytes at 2 weeks. Image analysis of alcian blue stained slides also showed significantly higher percentage of positive alcian blue stain in G 2 chondrocytes. This result suggests that 808-nm InGaAs diode laser with 1.0 W power output although cannot stimulate cell proliferation it can increase the cell secretion activity and sGAG deposition in alginate beads.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.18 no.4
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• pp.234-265
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• 2013

Oceanic current maps in the secondary school science and earth science textbooks have played an important role in piquing students's inquisitiveness and interests in the ocean. Such maps can provide students with important opportunities to learn about oceanic currents relevant to abrupt climate change and global energy balance issues. Nevertheless, serious and diverse errors in these secondary school oceanic current maps have been discovered upon comparison with up-to-date scientific knowledge concerning oceanic currents. This study presents the fundamental methods and strategies for constructing such maps error-free, through the unification of the diverse current maps currently in the textbooks. In order to do so, we analyzed the maps found in 27 different textbooks and compared them with other up-to-date maps found in scientific journals, and developed a mapping technique for extracting digitalized quantitative information on warm and cold currents in the East Sea. We devised analysis items for the current visualization in relation to the branching features of the Tsushima Warm Current (TWC) in the Korea Strait. These analysis items include: its nearshore and offshore branches, the northern limit and distance from the coast of the East Korea Warm Current, outflow features of the TWC near the Tsugaru and Soya Straits and their returning currents, and flow patterns of the Liman Cold Current and the North Korea Cold Current. The first draft of the current map was constructed based upon the scientific knowledge and input of oceanographers based on oceanic in-situ measurements, and was corrected with the help of a questionnaire survey to the members of an oceanographic society. In addition, diverse comments have been collected from a special session of the 2013 spring meeting of the Korean Oceanographic Society to assist in the construction of an accurate current map of the East Sea which has been corrected repeatedly through in-depth discussions with oceanographers. Finally, we have obtained constructive comments and evaluations of the interim version of the current map from several well-known ocean current experts and incorporated their input to complete the map's final version. To avoid errors in the production of oceanic current maps in future textbooks, we provide the geolocation information (latitude and longitude) of the currents by digitalizing the map. This study is expected to be the first step towards the completion of an oceanographic current map suitable for secondary school textbooks, and to encourage oceanographers to take more interest in oceanic education.

• Fire Science and Engineering
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• v.31 no.5
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• pp.53-62
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• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.273-278
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• 2019

The multi-layer insulating curtains used in the experiment was produced in six combinations using non-woven fabric containing aerogel and compared and analyzed by measuring heat flux and heat perfusion rates due to weight, thickness and temperature changes. Using silica aerogel, which have recently been noted as new material insulation, this study tries to produce a new combination of multi-layer insulating curtains that can complement the shortcomings of the multi-layer insulating curtains currently in use and maintain and improve its warmth, and analyze the thermal properties. The heat flux means the amount of heat passing per unit time per unit area, and the higher the value, the more heat passing through the multi-layer insulating curtain, and it can be judged that the heat retention is low. The weight and thickness of multi-layer insulation curtains were found to be highly correlated with thermal insulation. In particular, insulation curtains combined with aerogel meltblown non-woven fabric had relatively higher thermal insulation than insulation curtains with the same number of insulation materials. However, the aerogel meltblown non-woven fabric is weak in light resistance and durability, and there is a problem that the production process and aerogel are scattering. In order to solve this problems, the combination of expanded aerogel non-woven fabric and hollow fiber non-woven fabric, which are relatively simple manufacturing processes and excellent warmth, are suitable for use in real farms.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.7
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• pp.848-857
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• 2018

Recently, around the world, active development of new renewable energy sources including solar power, waves, and fuel cells, etc. has taken place. Particularly, floating offshore wind farms have been developed for saving costs through large scale production, using high-quality wind power and minimizing noise damage in the ocean area. The development of floating wind farms requires an evaluation of the Maritime Safety Audit Scheme under the Maritime Safety Act in Korea. Floating wind farms shall be assessed by applying the line and area concept for systematic development, management and utilization of specified sea water. The development of appropriate evaluation methods and standards is also required. In this study, proper standards for marine traffic surveys and assessments were established and a systemic treatment was studied for assessing marine spatial area. First, a marine traffic data collector using AIS or radar was designed to conduct marine traffic surveys. In addition, assessment methods were proposed such as historical tracks, traffic density and marine traffic pattern analysis applying the line and area concept. Marine traffic density can be evaluated by spatial and temporal means, with an adjusted grid-cell scale. Marine traffic pattern analysis was proposed for assessing ship movement patterns for transit or work in sea areas. Finally, conceptual design of a Marine Traffic and Safety Assessment Solution (MaTSAS) was competed that can be analyzed automatically to collect and assess the marine traffic data. It could be possible to minimize inaccurate estimation due to human errors such as data omission or misprints through automated and systematic collection, analysis and retrieval of marine traffic data. This study could provides reliable assessment results, reflecting the line and area concept, according to sea area usage.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.2
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• pp.85-96
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• 2019

Solar radiation is an important variable for estimation of energy balance and water cycle in natural and agricultural ecosystems. A deep neural network (DNN) model has been developed in order to estimate the daily global solar radiation. Temperature and precipitation, which would have wider availability from weather stations than other variables such as sunshine duration, were used as inputs to the DNN model. Five-fold cross-validation was applied to train and test the DNN models. Meteorological data at 15 weather stations were collected for a long term period, e.g., > 30 years in Korea. The DNN model obtained from the cross-validation had relatively small value of RMSE ($3.75MJ\;m^{-2}\;d^{-1}$) for estimates of the daily solar radiation at the weather station in Suwon. The DNN model explained about 68% of variation in observed solar radiation at the Suwon weather station. It was found that the measurements of solar radiation in 1985 and 1998 were considerably low for a small period of time compared with sunshine duration. This suggested that assessment of the quality for the observation data for solar radiation would be needed in further studies. When data for those years were excluded from the data analysis, the DNN model had slightly greater degree of agreement statistics. For example, the values of $R^2$ and RMSE were 0.72 and $3.55MJ\;m^{-2}\;d^{-1}$, respectively. Our results indicate that a DNN would be useful for the development a solar radiation estimation model using temperature and precipitation, which are usually available for downscaled scenario data for future climate conditions. Thus, such a DNN model would be useful for the impact assessment of climate change on crop production where solar radiation is used as a required input variable to a crop model.

• Journal of agriculture & life science
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• v.51 no.5
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• pp.91-101
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• 2017

The in vitro experiment was conducted to ensure the supplemental level of spent Flammulina velutipes mushroom substrates(SMS) as an energy source in manufacturing of rye silage. Rye harvested at heading stage was ensiled with spent mushroom substrates of 0%(Control), 20%(R-20), 40%(R-40) and 60%(R-60) as fresh matter basis for 6week. The rumen fluid for preparation of in vitro solution was collected from two cannulated Holstein bulls fed a 40:60 concentrate:timothy diet. The experiment was conducted by 3, 6, 9, 12, 24, and 48 hrs of ncubation time with 3 replications. The silages were evaluated fermentation characteristics and dry matter digestibility(DMD) in vitro. The pH of in vitro solution was inclined to decrease with elapsing the incubation time, and that of the R-60 was significantly(p<0.05) lower than the other treatment at 48 hr of incubation. The microbial growth in vitro was inclined to increase with elapsing the incubation time, and that of the R-20 was significantly(p<0.05) greater than the Control at 48 hr of incubation. Gas production was greater(p<0.05) in the Control than the other treatments at 48 hr of incubation. In vitro dry matter digestibility(IVDMD) was higher with increasing the supplemental level of SMS, and was significantly(p<0.05) lower in the Control compared with other treatments throughout whole incubation time. The IVDMD for R-60 was the highest(p<0.05) among treatments at 24 hr and 48 hr of incubation. Considering of above results and the availability of SMS, SMS could be supplemented by 60% in fresh matter basis for rye silage fermentation.