• Economic and Environmental Geology
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• v.15 no.1
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• pp.17-32
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• 1982

The Wolak tungsten-molybdenum deposits are tungsten-molybdenum bearing quartz veins which filled the fractures in Pre-Cambrian pebble-bearing calcareous hornfels, hornfels and Cretaceous granite. There are two vein groups in this mine, Dongsan vein group in the west and Kwangcheon vein group in the east. The ore minerals are wolframite, scheelite, molybdenite, native bismuth, bismuthinite, pyrite, arsenopyrite, chalcopyrite, cubanite, stannite, pyrrhotite, sphalerite, galena, marcasite, Pb-Bi sulfosalt and ilmenite. Quartz, calcite, beryl, fluorite, muscovite, rhodochrosite and siderite are gangue minerals. Fluid inclusion studies were carried out for the quartz, beryl, scheelite, early and late fluorite. Fluid inclusion studies reveal that liquid-gas inclusions are most common and occur in all of the minerals examined. Filling degree of the inclusions in the late fluorite is much higher than that of the inclusions in quartz and early fluorite. Liquid $CO_2$ bearing liquid-gas inclusions occur in quartz and early fluorite. Liquid, gas and solid phase inclusions occur in quartz, beryl and scheelite. Salinities of inclusions in quartz and beryl from Dongsan vein group range from 3.9 to 8.0, from 5.3 to 7.7 wt.% NaCl equivalent respectively. Salinities in the late fluorite range from 1.5 to 3.2 wt.% NaCl equivalent. In Kwangcheon vein group salinities range from 3.9 to 9.6 wt.% NaCl equivalent in quartz, from 2.8 to 7.3 wt.% NaCl equivalent in early fluorite, from 1.3 to 1.5 wt.% NaCl equivalent in late fluorite. Homogenization temperatures of inclusions range from $239^{\circ}$ to higher than $360^{\circ}C$ in quartz, over $360^{\circ}C$ in scheelite, from $288^{\circ}C$ to higher than $360^{\circ}C$ in beryl, and from $159^{\circ}$ to $202^{\circ}C$ in late fluorite of the Dongsan vein group. In Kwangcheon vein group, homo genization temperatures of inclusions range from $240^{\circ}C$ to higher than $360^{\circ}C$ in quartz and from $240^{\circ}$ to $328^{\circ}C$ in early fluorite. As a whole, in Dongsan and Kwangcheon vein groups it seems that there are no distinct differences in mineralogy, salinities and homogenization temperatures. No distinct variations in homogenization temperatures are revealed through about 300 m vertically in both district. The faint trend of increase in salinities in the lower level can be detected. The salinity, $CO_2$ content and the temperature of ore fluid were much higher in the early vein stage and then dropped off in the late stage of mineralization as represented by the quartz and fluorite inclusion data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.228-234
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• 2016

The aim of this study was to develop pharmaceutical dosage forms with a bi-phasic drug using a double extrusion approach. Hot melt extrusion was performed using a co-rotating twin-screw extruder. The. 1st melt extrusion was performed using polymer with a relatively higher Tg, such as HPMC and the 2nd melt extrudate was obtained using the 1st extrudate and polymers with a lower Tg, such as HPMC-AS and PEO. In addition, the formulation with all the content in the same proportion as the double extudate was produced using single extrusion for comparison. Physical characterization was performed on the formulations employing differential scanning calorimetry (DSC). In vitro release tests were studied using a USP Type-I apparatus at $37{\pm}0.5^{\circ}C$ and 100 rpm. The similarity factor (f2) was also used to check the difference statistically. The DSC results indicated that the crystallinity of ibuprofen was changed to an amorphous state after extrusion in both double and single melt extrusion. Double melt extrudate with ibuprofen showed the desired release in acidic media (pH 1.2) in the first two hours and basic (pH 6.8) during six hours. Double melt extrudate with glimepiride showed faster release in 60 min of over 80%, whereas the single extrudate with glimepiride showed retarded release due to the interaction with HPMC. The similarity factor(f2) value was 28.5, which demonstrates that there were different drug release behavior between the double and single extrusion. Consequently, the double melt extrudated formulation was robust and gave the desired drug release pattern.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.147-153
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• 2017

BACKGROUND: Soil water content strongly depends on weather condition and irrigation, and it could influence on crop nutrient use efficiency. This study was performed to assess nutrient uptake of soybean by soil water condition. METHODS AND RESULTS: In this study, nutrient leaching and crop uptake as affacted by water management practice was investigated using weighing lysimeter which is located in National institute of agricultural science, Wanju, Jeonbuk province from June 2015 to October 2016. Water supply for soybean (cv. Daewon) was managed with irrigation and rainfall. Nitrate leaching was greatest in the rainfall treatment at early July 2016. Yield of soybean in the rainfall treatment was only 25% compared to the irrigation due to the drought at flowering and podding period. The uptake of nitrogen was considerably reduced by drought whereas the uptake of phosphorus and potassium was less affected by drought. CONCLUSION: It was proven that nitrogen loss and uptake were dependent on soil water condition. Therefore, irrigation water management to maintain available soil moisture capacity is critical to nitrogen uptake and yield of soybean.

• Journal of Applied Biological Chemistry
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• v.52 no.1
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• pp.33-37
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• 2009

A saccharified-rice was fermented using Leuconostoc(Ln.) mesenteroides KC51 strain in various dry matter (DM) contents (4%, 8%, and 12%) at $30^{\circ}C$ for 18 h. The changes of viable cell number, acid production and phytate degradation in saccharified-rice during fermentation were investigated. The viable cell population of Ln. mesenteroides KC51 was increased rapidly in proportion to DM contents during the 9 h of cultivation. The changes of pH and titratable acidity in saccharified-rice were dependent on DM contents. At high DM content (12%), the viable cell number of Ln. mesenteroides KC51 increased to 9.56 log CFU/g after 6 h of fermentation. The pH and titratable acidity reached to pH 3.38 and 0.93% after 18 h of fermentation, respectively. The phytate, known as an antinutrient factor, in saccharified-rice was degraded by Ln. mesenteroides KC51 cultivation. The decrease of phytate during fermentation approximately coincided with the increase of Ln. mesenteroides KC51 population observed in fermented saccharified-rice. Regardless of DM contents, the levels of phytate were reduced to around 50% of initial concentration.

• The Journal of Korean Society for School & Community Health Education
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• v.20 no.3
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• pp.113-122
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• 2019

Objectives: This study was conducted to investigate the snack intake and brushing behavior according to the oral health education experience in some schools in Busan, and to investigate whether the oral health education experience affects the snack intake and brushing behavior. Methods: This study surveyed the entire fourth grade of elementary school in two districts by participating in university-linked oral health education activities run under the jurisdiction of the education office business to examine changes in the behavior of elementary school students in their snack intake and toothbrush. The survey was conducted on oral health education in elementary schools, prior oral health education experience before and after the activity, whether or not the brushing classroom was operated, and contents related to eating snacks and brushing behaviors. Result: Among the general characteristics of some schools in Busan, 69.9% of students have experience in oral health education and 30.1% of people have no experience in oral health education. 20.0%, 16.3% were 'normal' and 63.7% were 'helpful'. The brushing behavior according to the oral health education was 44.9% in the number of brushings, 44.9% in the number of brushings, 45.7% in 2-3 minutes in the time of brushing, 41.2% in the brushing method by sweeping the brush up and down. In the daily brushing period, 'after breakfast' was the highest at 72.3%, and the parent's brushing instruction was 'to lead' at 65.1%. The amount of sugar in subjective snacks was the highest with 60.6% of sugar content, and the parents had the highest level of 52.2% for parents' snack intake. This result was more significant than the students without oral health education experience. Conclusion: Based on the results of this study, the number and time of brushing, the method and timing of brushing according to the experience of oral health education. Students who had oral health education experience higher than those who did not have oral health education, but had a lower tendency to brush after lunch at school and before going to bed. For better oral health, the effect of oral health education will be better if the school has more systematic toothbrushing at lunch time and parental guidance at home.

• The KIPS Transactions:PartC
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• v.11C no.6 s.95
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• pp.799-806
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• 2004

A growing diversity of pervasive devices is gaming access to the Internet and other information. However, much of the rich multimedia contents cannot be easily handled by the client devices because of the limited communication, processing, storage and display capabilities. The in-tegration of voice, data and video service modified the target of networking technologies. Networks must have some the capabilities for in-tegration of various services and also for QoS support as required by each of those service. Because of these reasons, we developed EAGIS(Efficient ATM Gateway for real time Internet Service) to provide seamless multimedia service between the ATM network and the Internet. EAGIS consists of the interworking unit, content server, transcoding server, and the serveice broker to provide seamless multimedia service be-tween the ATM network and the Internet. In this paper, we design the architecture and transcoding service scenario of the EAGIS. When the RTP is used for the bi-directional communication, transcoding time is configured by the time-stamp of RTCP. When HTTP is used for unidirec-tional communication, self-timer is used. By using these reference time, standard transcoding method is applicable according to the frame trans-mission rate and network traffic load. And we can also assure the QoS of the multiple users` effective bandwidth by our algorithm.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.211-215
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• 2005

Three curcuminoids [curcumin (CUR), demethoxycurcumin(DEM), bisdemethoxycurcu in (BIS)] are major yellow pigments in turmleric (Curcuma longa L.) root. Contents of curcuminoids in turmeric roots collected from 6 locations were analyzed using, high performance liquid chromatography (HPLC) equipped with reversed-phase column, an UV-Vis detector at 420nm, and eluted with a mixture of acetonitrile: $0.1\%$ acetic acid in water (50 : 50, v/v) as mobile phase. The stability of curcuminoid pigments in $80\%$ methanol extract solution were investigated during storage in a freezer at $-20^{\circ}C$, room temperature in the dark, and light condition. Calibration curves for the determination of curcuminoids were made with significant linearity $(r^2=0.999**)$. Average content of total curcuminoids was 171.5 mg/g, with 91.6 mg/g of CUR, 56.9 mg/g of DEM, and 23.0 mg/g of BIS. Amount of curcuminoids during storage in a freezer was almost not changed while those in room temperature wert reduced and rapid degradation appeared after 60 days. Within 90 days, about $50\%$ curcuminoid decreased in the dark and about $70\%$ in the light condition, indicating the decomposition of curcuminoid pigments followed under light and heat.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.293-298
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• 2013

We aimed to provide the basic data for the development of a beverage using the juices from bioresources from Jeju. Our results show that pH and $^{\circ}Bx$ of the bioresources ranged 2.0-6.5 and 3.3-16.8, respectively. Rubus coreanus Miquel juice had the highest total phenol content (47.3 mg gallic acid equivalent (GAE)/100 mL). Citrus sphaerocarpa juice showed higher rates of 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging (86.8%) than those of other juices. However, the oxygen radical absorbance capacity (ORAC) value ($2,409.5{\mu}M$ TE/mL) of Citrus sudachi Hort. ex Shirai juice was higher than those of other juices. A high correlation (R=0.7343) was observed between the pH and ORAC values for the 20 bioresources. Furthermore, a high correlation (R=0.8752) was found between the phenolic contents and DPPH radical scavenging for the 5 citrus fruits. These results suggest that the bioresources in Jeju could be used as natural antioxidants for the development of functional foods, including healthy beverages.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.6
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• pp.736-745
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• 2002

In network delivery of compressed video, packets may be lost if the channel is unreliable like Internet. Such losses tend to of cur in burst like continuous bit-stream error. In this paper, we propose an effective error-concealment approach to which an error resilient video encoding approach is applied against burst errors and which reduces a complexity of error concealment at the decoder using data hiding. To improve the performance of error concealment, a temporal and spatial error resilient video encoding approach at encoder is developed to be robust against burst errors. For spatial area of error concealment, block shuffling scheme is introduced to isolate erroneous blocks caused by packet losses. For temporal area of error concealment, we embed parity bits in content data for motion vectors between intra frames or continuous inter frames and recovery loss packet with it at decoder after transmission While error concealment is performed on error blocks of video data at decoder, it is computationally costly to interpolate error video block using neighboring information. So, in this paper, a set of feature are extracted at the encoder and embedded imperceptibly into the original media. If some part of the media data is damaged during transmission, the embedded features can be extracted and used for recovery of lost data with bi-direction interpolation. The use of data hiding leads to reduced complexity at the decoder. Experimental results suggest that our approach can achieve a reasonable quality for packet loss up to 30% over a wide range of video materials.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.407-412
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• 2012

Wild grass is edible, and it grows in the mountains or field areas. Wild grass has diverse biological effects, such as antiobesity, anti-cancer, antioxidant activities and immune stimulation. Currently, many studies are aimed at enhancing the efficacy of medicinal foods on biological activity using a bioconversion technology, including the fermentation process. In this study, the quality characteristics and antioxidative activity of the fermented wild grass was investigated. The antioxidant activity of fermented wild grass was assessed by various radical scavenging assays using DPPH(2,2-diphenyl-1-picrylhydrazyl), FRAP(ferric ion reducing antioxidant power), reducing power, and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). Moisture contents of the fermented wild grass is $49.6{\pm}0.06%$. Contents of crude ash, crude protein, and crude fat were $0.65{\pm}0.01$, $0.65{\pm}0.04$, and $3.3{\pm}0.59%$, respectively. Moreover, fermented wild grass showed that the hunter's color values were 80.36(lightnees), 11.47(redness), and 44.53(yellowness), respectively. Total phenolic contents of the fermented wild grass was $1,185{\pm}159{\mu}g$ GAE(gallic acid equivalent)/g. The antioxidative activities of the fermented wild grass were significantly increased in a dose dependent manner. In addition, fermented wild grass did not show any cytotoxicity up to 500 ${\mu}g/m{\ell}$. However, the anti-adipogenic effect of the fermented wild grass extract was barely detectable. This antioxidant potential is partly due to the phenolic compounds that are present in the fermented wild grass extracts.