• Structural Engineering and Mechanics
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• v.49 no.2
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• pp.225-235
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• 2014

Cold expansion is an efficient way to improve the fatigue life of an open hole. In this paper, three finite element models have been established to bind the crack growth from an expanded hole and simulated. Expansion and its degree influence are studied using a numerical analysis. Stress intensity factors are determined and used to evaluate the fatigue life. Residual stress field is evaluated using a nonlinear analysis and superposed with the applied stresses field in order to estimate fatigue crack growth. Experimental tests are conducted under constant loading. Results of this investigation indicate expansion and its degree are beneficial to fatigue life and a good agreement was observed between FEM simulations and experimental results.

• Asian Journal of Turfgrass Science
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• v.7 no.1
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• pp.5-12
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• 1993

This experiment was conducted to study on the morphological change and growth retardation of Korean Lawograss (Zoysia japonica Steud.) under various shading degrees. Dada of plant height, No. of tiller, No. of stolon, No. of rhizome and fresh weight were measured on the l47days after transplanting in 1991. The results are summarized as follows. Plant height was increased at 30% shading degree or over, Maximum plant height was observed at 60% shadeing degree which was 24.2 cm. while full sunlight(control) was most shorted as 10.1 cm. Plant height rapidly was increased as to shading degree increase. The decreasing rate was lower in tiller number and stolon number(top parts of plant) compared with the rhizome number(under ground part) was severely decreased at 30% to 60% of shading. To increase the shading degree, rhizome number was most severely decreased under shading degrees. As degree of shading increase to 30%, 60% and 90%, fresh weight decrease to 66%, 44%, 22% to full sunlight, respectively. Relative growth retadation of Korean lawngrass was decreased by the order of number of rhizome, fresh weight, number of tiller, number of stolon. And these characters were highly significant accord-ing to the different shading degrees.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.190-194
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• 1993

This experiment was conducted to investigate the effects of concentrated sulfate on the germination rate, growth rate and the productivity of weight of kudzu (Pueraria thwnbergiana Bentham). The germination rate of kudzu seed by one or two treatment retreatment with the concentrated sulfate for minutes of 5. 10, 15 and 20 were determined respectively. The results obtained were summarized as follows; 1. In the time of concentrated sulfate treatment, the germination rate was the highest in the once treatment for 20 minute. and the retreatment was higher than the once treatment in the germination rate. 2. The changes of plant length by growth stage was grown gradually until for 60 day and rapidly after for 60 day. The growth rate was the highest in treatment for 15 minute than in other treatments. 3. The stem diameter. stem weight. fresh weight and root weight by the treatment with sulfate 15 minute as the treatment with once were high degree of productivity. 4. The number of branch. number of nodes and root weight by the growth stage were higher growth rate before for 90 day than after for 90 day, however stem weight and fresh weight were high degree of productivity after for 60 day.

• Korean Journal of Veterinary Research
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• v.26 no.2
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• pp.265-276
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• 1986

The bovine serum factor influencing the growth of swine testicle (ST) cell and the END effect of hog cholera SN test was studied. Throughout the experimental studies. following results were obtained and summarized. 1. Bovine whole serum of 16(76.2%) and 4(19.0%) samples out of 21 have shown a positive ST cell growth and the END effect, respectively. However, all of 21(100%) and 8(38.1%) samples out of 21 serum supernatant fractions, prepared from the bovine whole serum, have shown positive ST cell growth and END effect, respectively. 2. In the SDS-polyacrylamide gel electrophoretic analysis of the bovine whole serum and the supernatant fractions, ST cell growth inhibiting factor was proved present in globulin fraction and in whole gel plate as a diffusible component. 3. The END ineffective component present in the whole serum and its supernatant fraction was proved to be BVDV neutralizing antibody. 4. The difference of osmolarity, optical density, pH, degree of precipitant formation following heat cold treatment, A/G ratio as we11 as electrophoretic pattern and NDV SN index of the samples were not correlated to the degree of 57 cell growth and to the END effectiveness.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.4
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• pp.443-446
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• 1987

The present study was conducted to investigate the effects of stem extracts from perilla and buckwheat on the germination and seedling growth of barnyard grass and chinese cabbage. The major results obtained are as follows. The stem extracts showed inhibiting effects on seed germination. The degree of inhibition was much higher with the extracts of perilla than those of buckwheat and more sensitive to chinese cabbage than barnyard grass. The trends of inhibition effects on seedling growth were the same as in the seed germination with lower degree. The roots were more sensitive to the extracts than the tops with higher degree with buckwheat extracts.

• Journal of Distribution Science
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• v.9 no.3
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• pp.37-46
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• 2011

Since the Korean retail industry was made accessible to the big conglomerates and foreign retail companies, local traditional markets have faced serious problems. To sustain the local traditional markets' survival, the Korean government established various remedial policies for addressing, and many scholars published articles to suggest how to find solutions to, the problem. Unfortunately, the results have not been satisfactory. The purpose of this study is to find another way to help the Korean traditional retail market, from the view point of the Green Growth Policy, an initiative designed to address environmentally balanced economic growth in Korea. In order to survive and to maintain sustainable growth, it is incumbent upon retailers in the traditional market to understand the concept of the Green Growth Policy. A survey was conducted as a means of testing the degree of awareness of the Green Growth Policy, as well as determining the relationship between the degree of awareness and the degree of organizational commitment by the retailers in the local traditional markets. Interestingly, we were able to detect some of the features (e.g., they were distinguished by the elderly and the young, as well as low level of education and high level of education) in the traditional market retailers' demographic characteristics. We utilized the analysis of variance (ANOVA) statistical method to simultaneously compare the differences in retailers' demographic characteristics; the results were as follows: Overall, the results showed that the awareness of the Green Growth Policy, the degree of trust in the government's policy, levels of self-efficacy, and levels of organizational commitment were higher with the older traditional market retailers than the younger traditional market retailers. Specifically, the degree of trust in government policies (F=9.964,p < .05), levels of self-efficacy (F=5.532,p < .05), and levels of organizational commitment (F=5.697,p < .05) were statistically significant. Moreover, in the portion of the study that addressed the difference between education levels, all the variables were averaged in the higher education category of the traditional market retailers. Specifically, awareness levels of the Green Growth Policy (F=8.564,p < .005) and levels of self-efficacy (F=6.754,p < .005) were statistically significant. These results revealed that the traditional market retailers' demographic characteristics should be considered important factors in order to realize their policy. The results of the study showed the following: 1) The degree of awareness of the government's Green Growth Policy was statistically significant as it related to traditional market retailers' organizational commitment. 2) The degree of trust of the government's policy was significantly moderated between the awareness of the government's Green Growth Policy and the traditional market retailers' organizational commitment. This result demonstrates that the traditional market retailers' awareness of the government's Green Growth Policy will show more organizational commitment with higher levels of trust of the government's policy. 3) It also revealed that traditional market retailers' self-efficacy was fully mediated between the awareness of the Green Growth Policy of the government and traditional market retailers' organizational commitment. The results suggest that the government should show an interest in showing traditional market retailers how to enhance their traditional markets. Implications and future research directions are also discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.3
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• pp.117-121
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• 2003

Nickel(Ni) powders were prepared from the mixture of nickel chloride and magnesium stearate by a hydrogen reduction process, and the effect of reaction temperature and the addition of magnesium stearate on the chracteristics of the powders were investigated. The effect of size reduction of nickel particles was observed in the presence of magnesium stearate owing to the inhibition of excess growth of paricles. The size reduction and the degree of agglomeration of the particles affected by the amounts of liqiud phase, which related to the increase of magnesium stearate.

• Korean Journal of Artificial Intelligence
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• v.7 no.1
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• pp.17-22
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• 2019

The rapid development of artificial intelligence technology has exerted a great influence on all fields of the world, which of course also affects the world economy. This has also aroused a large number of economists' interest in this proposition. Since the definition of artificial intelligence is not unified yet, the results from previous researches are not reliable enough. At present, most scholars use the neoclassical growth model or task-based model to explore the path of artificial intelligence on economic variables. There into, most of them use the degree of automation to represent the artificial intelligence. They find that the degree of automation can change the proportion of industries. This only verifies that artificial intelligence can affect the economic variables. But the magnitude of artificial intelligence on economic variables can not be correctly estimated. Therefore, in order to have a better understanding on the impact of artificial intelligence on economic growth, this paper systematically reviews and collates previous literature on this topic. The results of this paper indicate that both in theoretical and empirical studies, artificial intelligence has a positive effect on economic growth. Then, some suggestions and limitations have also been put forward accordingly.

• Journal of Magnetics
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• v.19 no.4
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• pp.333-339
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• 2014

Single crystal growth of $BaFe_{12}O_{19}$ by the solid state crystal growth method was attempted. Seed crystals of ${\alpha}-Fe_2O_3$ were pressed into pellets of $BaFe_{12}O_{19}$ + 2 wt% $BaCO_3$ and heat-treated at temperatures between $1150^{\circ}C$ and $1250^{\circ}C$ for up to 100 hours. Instead of single crystal growth taking place on the seed crystal, BaO diffused into the seed crystal and reacted with it to form a polycrystalline reaction layer of $BaFe_{12}O_{19}$. The microstructure, chemical composition and structure of the reaction layer were studied using scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), x-ray Diffraction (XRD) and micro-Raman scattering and confirmed to be that of $BaFe_{12}O_{19}$. XRD showed that the reaction layer shows a strong degree of orientation in the (h00)/(hk0) planes in the sample sintered at $1200^{\circ}C$. $BaFe_{12}O_{19}$ layers with a degree of orientation in the (hk0) planes could also be grown by heat-treating an ${\alpha}-Fe_2O_3$ seed crystal buried in $BaCO_3$ powder.

• Progress in Superconductivity and Cryogenics
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• v.19 no.2
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• pp.9-13
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• 2017

This study presents a simple method to control the seed orientation which leads to the various growth characteristics of a single grain REBCO (RE: rare-earth elements) bulk superconductors. Seed orientation was varied systematically from c-axis to a-axis with every 30 degree rotation around b-axis. Orientations of a REBCO single grain was successfully controlled by placing the seed with various angles on the prismatic indent prepared on the surface of REBCO powder compacts. Growth pattern was changed from cubic to rectangular when the seed orientation normal to compact surface was varied from c-axis to a-axis. Macroscopic shape change has been explained by the variation of the wetting angle of un-reacted melt depending on the interface energy between $YBa_2Cu_3O_{7-y}$ (Y123) grain and melt. Higher magnetic levitation force was obtained for the specimen prepared using tilted seed with an angle of 30 degree rotation around b-axis.