• Journal of KIISE:Databases
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• v.37 no.2
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• pp.92-103
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• 2010

The Web Ontology Language (OWL) has become the W3C recommendation for publishing and sharing ontologies on the Semantic Web. To derive hidden information from OWL data, a number of OWL reasoners have been proposed. Since OWL reasoners are memory-based, they cannot handle large-sized OWL data. To overcome the scalability problem, RDBMS-based systems have been proposed. These systems store OWL data into a database and perform reasoning by incorporating the use of a database. However, they do not consider complete reasoning on all types of properties defined in OWL and the database schemas they use are ineffective for reasoning. In addition, they do not manage updates to the OWL data which can occur frequently in real applications. In this paper, we compare various database schemas used by RDBMS-based systems and propose an improved schema for efficient reasoning. Also, to support reasoning for all the types of properties defined in OWL, we propose a complete and efficient reasoning algorithm. Furthermore, we suggest efficient approaches to managing the updates that may occur on OWL data. Experimental results show that our schema has improved performance in OWL data storage and reasoning, and that our approaches to managing updates to OWL data are more efficient than the existing approaches.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.6
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• pp.267-271
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• 2010

Super hydrophilic and high transparent $TiO_2$ thin films were successfully fabricated by sol-gel method without an irradiation of UV light. In addition, surfactant Tween 80 was used for increasing the transmittance of the thin films. When the contents of Tween 80 in $TiO_2$ solution were 0.0, 1.0, 3.0, 5.0 wt%, the transmittance of $TiO_2$ thin films was ca. 74.31%, 74.25%, 79.69%, 81.99% at 550 nm wavelength, respectively. The contact angles of fabricated $TiO_2$ thin films with or without Tween 80 were from ca. $4.0^{\circ}$ to $4.5^{\circ}$. The $TiO_2$ thin films annealed over $400^{\circ}C$ showed anatase crystal structure and the photocatalytic property that decomposed methyl orange with UV irradiation. The surface morphologies, optical properties and contact angle of prepared thin films with different contents of Tween 80 were evaluated by field emission scanning electron microscope (FE-SEM), X-ray diffratometer (XRD), UV-Vis spectrophotometer and contact angle meter.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.29-43
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• 2016

Pesto were prepared with five different nuts including pine nut, sunflower seed, pumpkin seed, walnut and almond to examine the antioxidant properties(total polyphenols, total flavonoids, electron donating ability) and sensory test(attribute difference, acceptance). Pesto were measured based on color value, pH, viscosity, total cell numbers for 0, 5, 10, 15 and 20 days at $4^{\circ}C$. The higher total phenol and total flavonoid content of pesto added with various nuts was higher antioxidant capacity. Basil pesto added with sunflower seeds and walnuts were considered to be more functional more than pine nuts addition. The attribute difference test results was the color intensity, nut taste, bitter taste, coarseness, oily taste, thickness were evaluated significant difference kinds of nuts. Gloss, basil flavor, nuts flavor, basil taste were not evaluated significant difference in kind of nuts. The preference test results reveal that the appearance, taste, texture and overall preference level was the highest in PNP(pinenut pesto) and SSP(sunflower seed). L value, pH, decrease while a value, b value and viscosity increased as kind of nuts in during storage. Total cell number increased and then decreased a little at a certain point. When prepared pesto, SSP(sunflower seed) was the highest in antioxidant property, and change of color value, pH, viscosity, total cell number were the lowest. In addition to the use of pine nuts, sunflower seeds have been identified are possible.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.291-298
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• 2016

In this study, zwitterionic surfactants were added to liposome systems at different pH conditions to understand the effect of surfactants on liposome characteristics. For this purpose, amine oxide surfactants having different hydrocarbon chain lengths were synthesized and the structure of the resulting product was elucidated by using $^1H$ NMR, $^{13}C$ NMR, and FT-IR. In addition, the physical properties of newly synthesized surfactants such as critical micelle concentration (CMC), surface tension and isoelectric point were measured. The stability characteristics of liposome systems including average particle sizes and zeta potentials were measured by varying pH and hydrocarbon chain lengths of an amine oxide surfactant. Effects of the pH and hydrocarbon chain length of an amine oxide surfactant on fluidity of a liposome membrane were also examined by measuring the deformability and the binding degree between the surfactant and liposome.

• Journal of Life Science
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• v.13 no.5
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• pp.668-674
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• 2003

This study was carried out to investigate the ACE inhibitory materials of Raja kenojei. Raja kenojei was sperated to fillet and viscera, and these were extracted with hot water. Antihypertensive activity was examined by mesearing angiotensin converting enzyme ACE inhibitory activity. ACE inhibitory activity of viscera at the concentration of 2% for Day 0 showed the highest value by 71.0%. But ACE inhibitory activity of fillet at 2% showed by 29%, which was lower antihypertensive activity than viscera. The protein content of viscerial hot water extracts in proximate composition showed the highest. And also, there was a large amount of aromatic and branched aliphatic amino acids in viscera than those in fillet. For the purification of antihypertensive material in visceral hot water extracts, it was separated and collected by Sephadex G-25 gel chromatography. The fraction (B) of 111 to 160 showed the highest ACE inhibitory activity by 65.1% at the concentration of 0.05%. But the other fractions (A and C) showed lower activity than B. These results demonstrate that crude hot water extracts of viscera from Raj kenojei may be useful as functional food ingredient with antihypertensive property.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.455-469
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• 2007

The study area, Bonggil-ri, Gyeongju, SE Korea, is composed of Cretaceous sedimentary rocks, and Tertiary igneous rocks and dykes. A research on fracture developing history and density distribution was carried out on well exposed Tertiary granites. The fractures developed in this area have the following sequence; NW-SE trending duo-tile shear bands (set a), NNW-SSE trending extensional fractures (set d), WNW-ESE trending extensional or normal fractures (set b), NE-SW trending right-lateral fractures (set c), WNW-ESE trending reverse fault reactivated from normal faults (set e) and NW-SE trending left-lateral faults reactivated from shear bands (set a) under brittle condition. According to the result of fracture density analysis, the fracture density in this area depends on rock property rather than rock age, and also higher fracture density is observed around fault damage zones. However, this high fracture density may also be related to the cooling process associated with dyke intrusion as well as rock types and fault movement. Regardless of the reason of the high fracture density, high fracture density itself contributes to fluid flow and migration of chemical elements.

• Culinary science and hospitality research
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• v.18 no.4
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• pp.255-265
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• 2012

This study aimed to determine the physicochemical and sensory qualities for yogurt dressing prepared with blueberry juice(0, 10, 15, 20, and 25%). As the amount of added blueberry juice increased, citric acid, malic acid and succinic acid contents increased, but tartaric acid, lactic acid and acetic acid contents decreased. The pH of control group(3.75) was higher than that of the others(3.68-3.48). Sweetness of yogurt dressings decreased as the amount of added blueberry juice increased. DPPH radical scavenging activity of the control group was 26.44%, whereas those of yogurt dressings with blueberry juice ranged from 63.16-87.46%. Color L and b values decreased significantly, whereas a value increased significantly by addition of blueberry juice. Viscosity of the control group was lower than those of the others. The sensory property results showed that yogurt dressing with 20% blueberry juice was rated best. It was also preferred most. These results suggest 20% of blueberry juice is the best substitution ratio for yogurt dressing.

• Journal of the Korean Ceramic Society
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• v.40 no.10
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• pp.954-960
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• 2003

To develop mobile phone antenna modules, glass-ceramics composites that are 20∼80 dielectric constant materials which has been fabricated. The glass-ceramics composites were based in the BNT (BaO-Nd$_2$O$_3$-TiO$_2$), and properties-a sintering and dielectric property-were investigated in its composites according to the $K_2$O-CaO-P$_2$O$_{5}$ system glass frits. The prepared ceramics were sintered at 900∼120$0^{\circ}C$ with the glass frit contents ranging from 10 to 40 wt%. The shrinkage and relative density grew into increasing glass frits and sintering temperature. Sintered composites showed the tendency that the dielectric constant ($\varepsilon$$_{r}$) and quality factor (Q${\times}$f) decreased in increasing glass frits and sintering temperature.

• The KIPS Transactions:PartD
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• v.12D no.6 s.102
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• pp.817-828
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• 2005

The main research problems in a mining frequent itemsets are reducing memory usage and processing time of the mining process, and most of the previous algorithms for finding frequent itemsets are based on an Apriori-property, and they are multi-scan algorithms. Moreover, their processing time are greatly increased as the length of a maximal frequent itemset. To overcome this drawback, another approaches had been actively proposed in previous researches to reduce the processing time. However, they are not efficient on a sparse .data set This paper proposed an efficient mining algorithm for finding frequent itemsets. A novel tree structure, called an $L_2$-tree, was proposed int, and an efficient mining algorithm of frequent itemsets using $L_2$-tree, called an $L_2$-traverse algorithm was also proposed. An $L_2$-tree is constructed from $L_2$, i.e., a set of frequent itemsets of size 2, and an $L_2$-traverse algorithm can find its mining result in a short time by traversing the $L_2$-tree once. To reduce the processing more, this paper also proposed an optimized algorithm $C_3$-traverse, which removes previously an itemset in $L_2$ not to be a frequent itemsets of size 3. Through various experiments, it was verified that the proposed algorithms were efficient in a sparse data set.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.6
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• pp.251-255
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• 2007

We made $(1-x)BCB-xBNT(BaNd_2Ti_4O_{12})$ (x=20, 30, 40, 50 vol%) composite thick film with a high dielectric constant and low loss by the hand casting method. Dielectric constant and dielectric loss of prepared thick film are measured at 1MHz and curing behavior of the film are observed through thermal analysis such as DSC. We investigated the effect of contents of BNT filler and curing behavior of film on dielectric properties of BCB-BNT composite. Dielectric constant increased with increasing BNT filler from 20 to 50 vol% and dielectric loss ($tan{\delta}$) decreased with increasing BNT filler. Dielectric constant and loss ($tan{\delta}$) of composite material was not nearly dependent on the curing behavior. But as a result of TCC (Temperature Characteristics of Coefficient) decreased with increasing the curing temperature, we confirmed that the curing of these composite system is most stable above $250^{\circ}C$.