• Journal of Intelligence and Information Systems
• /
• v.7 no.1
• /
• pp.17-25
• /
• 2001

Tree model is the most popular classification algorithm in data mining due to easy interpretation of the result. In CART(Breiman et al., 1984) and C4.5(Quinlan, 1993) which are representative of tree algorithms, the split fur classification proceeds to attain the homogeneous terminal nodes with respect to the composition of levels in target variable. But, fur instance, in the chum prediction modeling fur CRM(Customer Relationship management), the rate of churn is generally very low although we are interested in mining the churners. Thus it is difficult to get accurate prediction modes using tree model based on the traditional split rule, such as mini or deviance. Buja and Lee(1999) introduced a new split rule, one-sided purity for classifying minor interesting group. In this paper, we compared one-sided purity with traditional split rule, deviance analyzing churning vs. non-churning data of ISP company. Also reviewing the result of tree model based on one-sided purity with some simulated data, we discussed problems and researchable topics.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.26 no.6
• /
• pp.529-537
• /
• 1993

Several methods were examined for purification of docosahexaenoic acid (DHA, 22:6n-3) from skipjack Euthynnus pelamis orbital tissue oil, a marine by-product, and a modified method for isolation of a high purity DHA was proposed. Skipjack orbital tissue contained $55.4\%$ of total lipid(TL), and DHA accounted for $23.7\%$ of the TL. Application of low-temperature crystallization and urea inclusion compound methods to the orbital fatty acid mixture resulted in increases of DHA concentrations to approximately $46\%\;and\;61\%$, respectively. These methods were suitable for large production of DHA with relative low purity because of the simple purification procedure. DHA of approximately $74\%$ in purity was obtained by silver nitrate aqueous solution method, but the method gave a very low recovery($<10\%$). Silver nitrate-impregnated silica column chromatography was suitable for purification of a high purity DHA(purity, $>98\%$ and recovery, $>90\%$) A modified method, silver nitrate-impregnated silica column chromatography combined with low-temperature crystallization(two step purication method) was proposed as the most effective method to obtain DHA with high purity($99.9\%$) from the skipjack orbital oil.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.11
• /
• pp.1534-1538
• /
• 2010

Fed-batch cultures of Hansenula polymorpha were studied to develop an efficient biosystem to produce recombinant human serum albumin (HSA). To comply with this purpose, we used a high-purity oxygen-supplying strategy to increase the viable cell density in a bioreactor and enhance the production of target protein. A mutant strain, H. polymorpha GOT7, was utilized in this study as a host strain in both 5-l and 30-l scale fermentors. To supply high-purity oxygen into a bioreactor, nearly 100% high-purity oxygen from a commercial bomb or higher than 93% oxygen available in situ from a pressure swing adsorption (PSA) oxygen generator was employed. Under the optimal fermentation of H. polymorpha with highpurity oxygen, the final cell densities and produced HSA concentrations were 24.6 g/l and 5.1 g/l in the 5-l fermentor, and 24.8 g/l and 4.5 g/l in the 30-l fermentor, respectively. These were about 2-10 times higher than those obtained in air-based fed-batch fermentations. The discrepancies between the 5-l and 30-l fermentors with air supply were presumably due to the higher contribution of surface aeration over submerged aeration in the 5-l fermentor. This study, therefore, proved the positive effect of high-purity oxygen in enhancing viable cell density as well as target recombinant protein production in microbial fermentations.

• Journal of the Korean Society for Heat Treatment
• /
• v.25 no.1
• /
• pp.22-26
• /
• 2012

An influence of the addition of copper (0.5, 1.0 and 1.5 mass% Cu) on the microstructure and mechanical properties of high purity iron (99.998 mass%) was characterized. The microstructure and microhardness of high-purity iron based samples, which were rolled at room temperature and subsequently annealed, were investigated in this work. The microstructure of the samples has been observed by electron back scattering diffraction (EBSD) and the mechanical properties have been studied by using micro-Vickers hardness test. The results of microstructural observation showed that deformation band was formed in high purity iron by rolling at room temperature, and it was recovered by annealing up to about 900 K. The microhardness results showed that the softening of high-purity iron occurred by annealing up to about 900 K, while the hardness of iron added with about 0.5-1.5 mass% copper was kept over 100 Hv and at the early time of annealing reached a maximum. The hardness of iron added with a small amount of copper may be attributed to precipitation hardening as well as solution hardening. The orientation of crystal in recrystallized grain was almost same as that of deformed grain.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.13 no.4
• /
• pp.13-20
• /
• 2014

In this paper, the effects of a nonionic surfactant on the etch uniformity and the etch profile during the wet-etching process of high-purity aluminum were investigated for the fabrication of uniform micropattern arrays. To improve the surface roughness of a high-purity aluminum plate, a mechanical lapping process and an electrolytic polishing process were used. After electrolytic polishing process, the surface roughness, Ra, of the high-purity aluminum plate was improved from $1.25{\mu}m$ to $0.02{\mu}m$. A photoresist was used as an etching mask during the aluminum etching process, where the mixture of phosphoric acid, acetic acid, nitric acid, a nonionic surfactant and water was used as the aluminum etchant. Different amounts of the Triton X-100 nonionic surfactant were added to the aluminum etchant to investigate the effect of a nonionic surfactant during the wet-etching process of high-purity aluminum. The etch rate and the etch profile were measured by an optical interferometer and a scanning electron microscope.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.11
• /
• pp.1564-1570
• /
• 2016

The present study investigated the immunomodulatory effects of high-purity ${\beta}$-1.3/1.6-glucan on macrophages, natural killer (NK) cells, and T cell-mediated factors. Effect of high-purity ${\beta}$-1.3/1.6-glucan on cytotoxicity in macrophages was investigated. Using macrophages, cytotoxicity of high-purity ${\beta}$-1.3/1.6-glucan was evaluated by MTT assay. We treated high-purity ${\beta}$-1.3/1.6-glucan at concentrations of 10, 50, 100, 150, 200, and $250{\mu}g/mL$ in macrophages. High-purity ${\beta}$-1.3/1.6-glucan did not affect macrophage viability. Phagocytic activity was assessed using zymosan. Activity of high-purity ${\beta}$-1.3/1.6-glucan on macrophages significantly increased as compared with zymosan. We treated high-purity ${\beta}$-1.3/1.6-glucan to murine NK cells co-incubated with YAC-1 cells. High-purity ${\beta}$-1.3/1.6-glucan resulted in significantly increased activity of NK cells as compared with the control. In addition, treatment of macrophages with high-purity ${\beta}$-1.3/1.6-glucan resulted in significantly increased activity of T cell-mediated cytokine (IL-2, IL-12, $IFN-{\gamma}$, and $TNF-{\alpha}$) levels and CD4+/CD8+ T cells as compared with the control. In conclusion, high-purity ${\beta}$-1.3/1.6-glucan could enhance the immune response through activation of macrophages, NK cells, and T cell-mediated factors.

• Bulletin of the Korean Mathematical Society
• /
• v.42 no.3
• /
• pp.609-616
• /
• 2005

In this paper we show that we can extend the purity of left R-modules to the case of polynomial modules, bipolynomial modules, and also inverse polynomial modules.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2007.11a
• /
• pp.82.2-82.2
• /
• 2007

• East Asian mathematical journal
• /
• v.21 no.1
• /
• pp.105-112
• /
• 2005

In this paper we show that we can extend the purity extension properties of left R-modules to the various generalized inverse polynomial modules.

• Proceedings of the Optical Society of Korea Conference
• /
• 2005.02a
• /
• pp.44-45
• /
• 2005