• Computers and Concrete
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• v.12 no.3
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• pp.319-335
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• 2013

In this paper, the properties of the cement mortar modified with styrene acrylic ester copolymer were investigated. Expanded vermiculite as lightweight aggregate was used for making the polymer modified mortar test specimens. To study the effect of polymer-cement ratio and vermiculite-cement ratio on various properties, specimens were prepared by varying the polymer-cement and vermiculite-cement ratios. Tests of physical properties such as density, water absorption, thermal conductivity, three-point flexure and compressive tests were made on the specimens. Furthermore, a coupled thermal-structural finite element model of an entire corner wall was modelled in order to study the best material configuration. The wall is composed by a total of 132 bricks of $120{\times}242{\times}54$ size, joined by means of a contact-bonded model. The use of advanced numerical methods allows us to obtain the optimum material properties. Finally, comparisons of polymer-cement and vermiculite-cement ratios on physical properties are given and the most important conclusions are exposed.

• Journal of Korean Biological Nursing Science
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• v.14 no.1
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• pp.33-40
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• 2012

Purpose: The purpose of this study was to explore the relationship between cyber leisure activity and autonomic function in high school students. Methods: The subjects of this study were 242 second graders at high school located in D city. The research design was descriptive correlation study. Data were collected from August 26 to September 17, 2010, using a cyber leisure questionnaire and heart rate variability (SA-6000, Medicore, Korea) for autonomic function. Results: Total time for the cyber leisure activity was $391.3{\pm}262.0$ (min/week). Time for internet usage and computer game was $234.5{\pm}140.1$ (min/week) and $156.8{\pm}164.3$ (min/week), respectively. There were significant positive correlation between total cyber leisure time and sympathetic activity (r=.247, $p$ <.001). Conclusion: Excessive cyber leisure activity could increase sympathetic activities in high school students. Thus, nursing intervention to reduce the total cyber leisure time will be helpful to improve their neurophysiological status.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.237-242
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• 2000

We have synthesized ester compounds from the soybean oil and some Polymer alcohol compounds and studied the physical properties of the synthesized esters. We have performed this experiment for the purpose of testing the physical properties by soybean oil ester compounds as a water-soluble metal working lubricant.In addition, we have studied siy, surface tension, viscosity for the synthesized ester compounds in aqueous solution state varying the mixing ratio of water.

• Journal of the Korean Society of Food Culture
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• v.31 no.3
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• pp.235-242
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• 2016

The purpose of this study was to investigate the quality characteristics of makpyeon prepared with dry milled rice powder. The makpyeon samples prepared with dry milled rice powder and various amount makgeolli (0% (CON), 25% (M25), 50% (M50), 75% (M75), 100% (M100)), and analyzed for moisture content, pH, Hunter's color value, TPA and sensory evaluation. The moisture content did not showed significant difference among makpyeon samples. The L-value, a-value resulted in that CON showed the highest and decreased with the amount of makgeolli. The b-value of makpyeon samples showed that CON was the lowest and increased with the amount of makgeolli. TPA resulted in that M100 showed the highest hardness and the lowest adhesiveness, cohesiveness. Chewiness and gumminess of makpyeon samples were higher than those of CON. Based on quantitative descriptive analysis, the score of brightness, moistness, particle size and gloss of showed higher in CON that in makpyeon samples, firmness increased with the amount of makgeolli. Flavor attributes of liquor odor, sour odor, fermentation odor of makpyeon was stronger in makpyeon samples that in CON with the amount of makgeolli. Acceptance test resulted in makpyeon made with CON, 100% of makgeolli (M100) showed the significantly highest score in taste and overall acceptance.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.242-248
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• 2002

Previously, it was reported that the nonhomologous C-terminal regions of the D-hydantoinases are nonessential for catalysis, but affect the oligomeric structure of the enzyme [3]. In an effort to further confirm the above observation, the C-terminal region-inserted enzyme was constructed by attaching a peptide (22 residues) at the C-terminal of the D-hydantoinase from Bacillus thermocatenulatus GH2, and its structural and biochemical properties were compared with both the wild-type and C-terminal region-truncated enzymes. As a result, native tetrameric D-hydantoinase was dimerized as the truncated enzyme, and the inserted mutant with a new sequence was expressed as a catalytically active form in E. coli. Expression level of the inserted and truncated enzymes were found to be significantly increased compared to the level of the wild-type enzyme, and this appears to be due to the reduced toxic effect of the mutant enzymes on host cells. Dimerized enzymes exhibited increased thermo- and pH stabilities considerably when compared with the corresponding wild-type enzyme. Comparison of the substrate specificity between the mutant and wild-type enzymes suggests that the substrate specificity of the D-hydantoinase is closely linked with the oligomeric structure.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.7
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• pp.242-249
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• 1999

Spot welding is very important and useful technology in fabrication of an automobile body structure. Because fatigue strength of the spot welding point is however considerably lower than parent metal due to stress concentration at the nugget edge, accurate stress analysis and fatigue stength evaluation of spot welded lap joint are very important to valuate the reliability and durability of automobile body structure and to establish a criterion of long life fatigue design. Many invetigators have studied so far onsystematic fatigue strength evaluation with various methods. It is however necessary to verify their reliability and abailability for practical application to fatigue design of spot welded structure, Thus,in this study, fatigue strength evaluation methods of spot welded lap joint. which are the maximum principal stress method. the fracture and availability with the Weibull probability distribution. From the results, it was found that reliability and availability withe the Weibull probaility distribution. From the results, it was found that reliability and availability of the suggest fatigue strength estimation methods methods were higher than $\Delta$P-$N_f$ relation. However, among them , reliability of the maximum pricipal stress method was the highest.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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• pp.236-242
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• 1995

Biological control of soilborne plant pathogens by the addition of antagonistic microorganisms to the soil may offer a practical supplement or alternative to existing disease management strategies that depend heavily on chemical pesticides. Soil amendment with antagonistic microbes was non-effective because of high cost, low efficacy, and inconvenient usage on the treatment course. Therefore, seed coating formulation for the application of biological seed treatments has been being to apply successful disease suppression for many important crops. The objectives of this study were to investigate the optimal condition for the spore production of biocontrol agent Bacillus subtilis YBL-7 and the liquid coating formulation that contained a suspension of a proper aqueous binder, as well as a ground fine solid particulate material. The maximum yield has been obtained from 60 hrs-old culture at 30$\circ$C in spore forming (SF) medium containing 0.8% nutrient broth, 0.05% yeast extract, 10$^{-1}$ M MgCl$^{2}$, 10$^{-4}$ M MnCl$^{2}$, 10$^{-5}$ M dipicolinic acid, and pH 6.5. The optimal condition of dried spore preparation was achieved when cells of B. subtilis YBL-7 was heat-dried with 50$\circ$C for 2 hrs.

• Nuclear Engineering and Technology
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• v.38 no.3
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• pp.301-310
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• 2006

Destructive methods were used for the burnup determination of U-Zr alloy nuclear fuel irradiated in the High-flux Advanced Neutron Application Reactor (HANARO) at KAERI. The dissolution rate of unirradiated U-Zr alloy fuel in $HNO_3$/HF mixtures was investigated for the experimental conditions of a different temperature, and initial concentrations of HF and $HNO_3$. The irradiated U-Zr alloy fuel specimen was dissolved in a mixed acid condition of 3 M HNO3 and 1 M HF at $90^{\circ}C$ for 8 hours under reflux. The total burnup was determined from measurement of the Nd isotope burnup monitors. The method includes U, Pu, $^{148}Nd,\;^P{145}Nd+^{146}Nd,\;^{144}Nd+^{143}Nd$ and total Nd isotopes determination by the isotope dilution mass spectrometric method (IDMS) using triple spikes $(^{233}U,\;^{242}Pu\;and\;^{150}Nd)$. The effective fission yield was calculated from the weighted fission yields averaged over the irradiation period. The results are compared with that obtained by the destructive -spectrometric measurement of the $^{137}Cs$ monitor.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.237-242
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• 2013

Cervical cancer is the second most common cause of cancer in women and has a high mortality rate. Cisplatin, an antitumor agent, is generally used for its treatment. However, the administration of cisplatin is associated with side effects and intrinsic resistance. Morinda citrifolia (Noni), a natural plant product, has been shown to have anti-cancer properties. In this study, we used Noni, cisplatin, and the two in combination to study their cytotoxic and apoptosis-inducing effects in cervical cancer HeLa and SiHa cell lines. We demonstrate here, that Noni/Cisplatin by themselves and their combination were able to induce apoptosis in both these cell lines. Cisplatin showed slightly higher cell killing as compared to Noni and their combination showed additive effects. The observed apoptosis appeared to be mediated particularly through the up-regulation of p53 and pro-apoptotic Bax proteins, as well as down-regulation of the anti-apoptotic Bcl-2, Bcl-$X_L$ proteins and survivin. Augmentation in the activity of caspase-9 and -3 was also observed, suggesting the involvement of the intrinsic mitochondrial pathway of apoptosis for both Noni and Cisplatin in HeLa and SiHa cell lines.

• Proceedings of the KIEE Conference
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• 2000.11a
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• pp.236-242
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• 2000

NZP velocities were investigated on Ag sheathed multi filamentary Bi-2223 tape and direction type HTS cable. The critical current($I_c$) of Ag sheathed Bi-2223 tape and direction type HTS cable were 12 A, 63 A at 77 K, 0 T. NZP velocities of tape with two condition of DC and AC were almost same at each temperature. In case of DC, the NZP velocities of numerical analysis and experiment were almost same. NZP velocities of direction type HTS cable were 1.9-2.4 cm/sec. The result shows that the total transport current of spiral type HTS cable in $LN_2$ was 475[A], and transport current passed through almost the outer layer (2-layer). Also, AC transport losses in outer layer of HTS cable was proportion to $I^2$ and higher than losses of inner layer. And in case of $I_p=I_c$, calculated numerical loss density was concentrated on the edge of tape and most of loss density in cable was distributed outer layer more than inner layer.