• Journal of Industrial Technology
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• v.39 no.1
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• pp.7-14
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• 2019

Carbon nanotubes (CNT) on metal substrates are definitely beneficial because they can maintain robust mechanical stability and high conductivity between CNT and metal interfaces. Here, we report direct growth of CNT on Ni-based superalloy, Inconel 600, using thermal chemical vapor deposition (CVD) with acetylene feedstock in the growth temperature range of $400-725^{\circ}C$. Furthermore, we studied the effect of substrate pretreatment on the growth yield enhancement and growth temperature decrease of CNT on Inconel 600. Activation energy (AE) for CNT growth was estimated from the CNT height change with respect to the growth temperature. The AE values significantly decreased from 205.03 to 24.35 kJ/mol by the pretreatment of thermal oxidation of Inconel substrate at $725^{\circ}C$ under ambient. Higher oxidation temperature tends to have lower activation energy. The results have shown the importance of pretreatment temperature on CNT growth yield and growth temperature decrease.

• YAKHAK HOEJI
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• v.5 no.1
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• pp.10-15
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• 1960

In order to know the effect on the growth of experimental rats, this, this experimental rats, this experiment was carried out on two groups of rats-a rice-diet animal group and a stock-diet animal group. Results of the growth experiment are shown in the tables 3 and 4, and growth curves are shown in the figures 1 and 2. The growth curves are shown in the figures 3 and 4. Based on the statistical analysis of growth rats, the male group on stock-diet was stimulated significantly in its growth by adding antler. The female group on rice-diet was also significantly stimulated in growth by anter. The other groups are not significant but it seems likely that the growths wers stimulated. As shown in table 7, the numbers of days when the body weight of the animals in each group became two times, three times, three times, and four times are discussed. This method of analysis shows clearly the stimulation of growth by adding antler in each group in both sexes. It can be summarized that the antler stimulates the growth of the experimental rats but it is not discussed in this paper whether this stimulation in the growth might be due to calcium, vitamins and amino acids in antler or to an unknown growth factor.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.297-303
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• 2019

The purpose of this study was to investigate the moderating effect of growth mindset between female adolescents' domestic abuse experience and school adaptation. For this purpose, a survey was conducted on 485 female adolescent girls in D city, Chungcheongnam-do, and the data collected were analyzed for differences test, correlation analysis, and regression analysis of moderating effects. Findings are as follows. First, school adaptation differed according to parents' earning income and academic achievement. Second, growth mindset and school adaptation showed significant positive correlation, but home abuse showed negative correlation with other variables. Third, the result of regression effect of moderating effect showed that the growth mindset for personality had a moderating effect. Finally, based on this study, we discussed ways to improve the school life of female students and teenagers. Specifically, it was suggested to consider the growth mindset and age for personality.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.10a
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• pp.232-237
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• 2001

The evaluation of specimen thickness effect of fatigue crack growth life by the simulation of probabilistic fatigue crack growth is presented. In this paper, the material resistance to fatigue crack growth is treated as a spatial stochastic process, which varies randomly on the crack surface. Using the previous experimental data, the non-Gaussian(eventually Weibull, in this report) random fields simulation method is applied. This method is useful to estimate the probability distribution of fatigue crack growth life and the variability due to specimen thickness by simulating material resistance to fatigue crack growth along a crack path.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.21.1-21.1
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• 2011

Vertically aligned single-crystal ZnO nanowires have been successfully grown on c-plane sapphire substrate using chemical vapor deposition (CVD) without catalyst. According to growth temperatures, it was changed ZnO growth characteristic. We investigated the effect of substrate temperatures on the growth ZnO films or nanowires on c-plane (0001) sapphire substrates. The ZnO films were acquired at $500^{\circ}C$, whereas the ZnO nanowires were obtained at $600^{\circ}C$, $700^{\circ}C$, and $800^{\circ}C$. The growth behavior diameter and growth rate of ZnO were changed due to different temperature. As a result of analyzing in-plane residual stress by X-ray diffraction, the optimized condition of ZnO nanowires were at $600^{\circ}C$.

• Journal of Environmental Science International
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• v.11 no.9
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• pp.979-985
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• 2002

Laboratory experiments were conducted to investigate the effect of ceramic-treated water on the inhibition of algal growth. The growth of Scenedesmus quadricauda and Chlorella vulgaris was enhanced by the ceramic-treated water in Allen medium containing high concentration of nutrients, but inhibited in natural water containing low concentration of nutrients. The growth of Oscillatoria tenuis and Microcystis aeruginosa was inhibited in both Allen medium and natural water. When comparing the effects of ceramic-treated water 1 (NC1) and 2 (NC2), the growth of O. tenuis and M. aeruginosa was somewhat enhanced by NC1, whereas inhibited by NC2. Therefore, it is suggested that NC2 can be more effective than NC1 in controlling the algal growth.

• Journal of the Korean Ceramic Society
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• v.33 no.11
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• pp.1203-1208
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• 1996

Crack growth tests on silicon nitride have been made to clarify the crack growth characteristics under static and cyclic loading. Under constant K(K: stress intensity factor) static loading the crack growth rate in silicon nitride decreases with increasing crack extension and is finally arrested. The cack growth resistiance is largely reduced by the application of stress cycling and though the crack growth resistiacne increases with increasing of crack extension the increasing rate is much smaller under cyclic loading than under static loading.

• Journal of Power System Engineering
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• v.5 no.2
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• pp.50-56
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• 2001

In this study, the effect of specimen thickness and stress ratio on fatigue crack growth in S45C steel was investigated. Acoustic emission was monitored during the fatigue crack growth test. Both crack closure and AE technique were used in assessing fatigue crack growth behavior. Constant amplitude loading tests were performed on CT type specimen with three different thicknesses and stress ratios. Crack closure was investigated to explain the influence of specimen thickness and stress ratio on the fatigue crack growth in the second growth region. The crack closure effect was decreased with specimen thickness and stress ratio.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1041-1050
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• 2000

In this paper the effect of specimen thickness on fatigue crack growth with the spatial distribution of material properties is presented. Basically, the material resistance to fatigue crack growth is treated as a spatial stochastic process, which varies randomly on the crack surface. The theoretical autocorrelation functions of fatigue crack growth resistance with specimen thickness are discussed for several correlation lengths. Constant ${\Delta}K$ fatigue crack growth tests were also performed on CT type specimens with three different thicknesses of BS 4360 steel. Applying the proposed stochastic model and statistical analysis procedure, the experimental data were analyzed for different specimen thicknesses for determining the autocorrelation functions and probability distributions of the fatigue crack growth resistance.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.350-354
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• 2000

The growth promotion of a Taxus brevifolia cell suspension culture was investigated using conditioning factors. The conditioning factors produced and secreted from cultured cells usually stimulate cell division and the production of secondary metabolites. Therefore, the effective incubation time for the optimal secretion of conditioning factors was firstly determined for the promotion of cell growth. Conditioned media obtained by cultivating for 2 and 5 days showed the promotion of initial cell growth during the early cell growth period. However, the positive effect of the conditioning factors on the initial cell growth did not continue because of the depletion of the medium nutrients. Accordingly, the addition of a carbon source to the conditioned medium prolonged the positive effect on the cell growth. The addition of sucrose to the conditioned medium resulted in the maximum cell density being reached 4 days earlier compared to the control group and an increased substrate yield.