• KSBB Journal
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• v.13 no.5
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• pp.469-476
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• 1998

Among 31 water-born microbial strains isolated from various sites in Korea, strain DJ-4 was selected as a test organism for toxicity measurements in that its growth was completely inhibited by the presence of 668.4 mg/L of chloroform and 297.5 mg/L of toluene in the liquid LB medium whereas others did not. It was observed that lag periods and specific growth rates of DJ-4 batch vial cultures were prolonged and decreased, respectively, by phenol, benzene, toluene, ethylbenzene, p-xylene, perchloroethylene, trichloroethylene, and chloroform at the concentrations between 3.6 and 417.8 mg/L. There changes were found to be linear with respect to the concentrations of the toxic compounds. From the first-order regression equations, 50% effective concentrations (EC50${\mu}$ for concentrations of toxic compounds causing 50% decrease of specific growth rates and EC50lag for 50% increase of length of lag periods) were calculated for each compounds. By comparing DJ-4 EC50${\mu}$ values with Daphnia LC50's from a literature for benzene, ethylbenzene, toluene, and trichloroethlyene, it was concluded that microbial specific growth could be a new, fast, and reliable parameter for toxicity tests.

• Journal of Korean Academy of Nursing
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• v.42 no.6
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• pp.907-915
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• 2012

Purpose: A diagnosis of breast cancer is one of the most traumatic events that threatens a woman's life, but while women adapt to and overcome these threats, they not only experience negative aspects, but also growth. The purpose of this study was to identify the many factors that affect growth, and to provide fundamental information for nursing interventions, which can help the women in their growth. Methods: The participants in this study were 131 married women patients with breast cancer, who were on medical treatment in one of two university hospitals, in Seoul and Chungnam. Data were collected for posttraumatic growth, self-esteem, cancer coping questionnaire, marital intimacy, and body image. The data were analyzed using the SPSS 19.0 program (IBM). Results: Interpersonal cancer coping, intrapersonal cancer coping (planning) and self-esteem accounted for 29.0% of posttraumatic growth. Conclusion: These findings indicate that in order to help the women's growth after the trauma of breast cancer, it is necessary to enhance their self-esteem, and to develop psycho-social nursing supportive programs.

• Journal of Power System Engineering
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• v.18 no.2
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• pp.62-69
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• 2014

In this paper, in order to investigate the effects of marco and microscopic observations of fatigue crack growth in friction stir welded (FSWed) 7075-T651 aluminum alloy plates, fatigue crack growth tests were performed under constant amplitude loading condition at room temperature with three different pre-cack locations, namely base metal (BM-CL) and two kinds of pre-crack locations in welded joints, weld metal (WM-CL) and heat affected zone (HAZ-CL) specimens. The fatigue crack growth behavior of FSWed 7075-T651 aluminum alloy plates were discussed based on the marco and microscopic fractographic observations. The marcoscopic aspects of surface crack growth path for BM-CL and HAZ-CL specimens indicate relatively straight lines, however, the crack growth paths of WM-CL specimens grow first straight and by followed toward the TMAZ and HAZ. The microscopic aspects of fatigue fracture for BM-CL and HAZ-CL specimens indicate typical fatigue striation, but WM-CL showed intergranular fracture pattern by micro structural changes of FSW process.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.3
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• pp.145-151
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• 2006

The purpose of this study was to analyze the relationship between the annual variation in diameter growth of Quercus spp. and climatic factors such as monthly temperature, precipitation and solar radiation in central and northern Korea. Annual diameter growth was measured by using stem cores of 262 Quercus trees, and the correlation between the diameter growth and the climatic factors was analyzed. Mean diameter growth of Quercus spp. in Jungwangsan was larger than that in Woraksan, and mean diameter growth by the species was large in order of Q. serrata>Q. variablis>Q. mongolica>Q. dentata. The diameter growth pattern of Quercus spp. in Woraksan was different from that in Jungwangsan. Positive correlations between diameter growth of Quercus trees and temperature or the solar radiation during July were found in Jungwangsan. Significant correlations between diameter growth and solar radiation during March and precipitation during June were found in Woraksan. It is suggested that climatic factors similarly affect the diameter growth of Quercus spp. in a mountainous terrain, but influences of the climatic factors depend on other environmental conditions such as altitude, topography and soil depth.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.2 no.1
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• pp.1-9
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• 1992

Radiation heat transfer was calculated for initial stage of crystal growth in Czochralski crystal growth system. View factors among surface elements were calculated for the estimation of heat evolution and all the surfaces were assumed to be diffuse-gray. The values of view factors were greatly different along the position of surface elements. The dissipated amounts of heat flux from the melt surface were 3.6 times larger than those from the crystal surface at the initial stage of crystal growth and this amounts were greater when the surface elements were not considered. The trijunction part of the crystal was greatly affected by the melt surface near the crystal. Consequently radiation heat transfer between surface elements must be considered in order to correctly simulate the initial crystal growth.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.4
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• pp.121-129
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• 2014

This study was carried out to develop an efficient plant growth system that can be controlled by altering the wavelength and illumination using a LED module. If it is possible to develop a system that can be controlled in this manner, utilizing different characteristics in the meaningful wavelength band depending on the growth time or type of plant, the plant growth conditions can be optimized. In order to this, red, green, blue and white LEDs are arrayed in a rectangle, consisting of LED modules which can be combined with each other. Consequently, the array can be used to select the optimal light conditions with monochromatic red, green, blue and white LEDs, or mixed LEDs, for plant growth. Experiments on the characteristics of the wavelengths to evaluate the efficiency of the plant growth system were performed. The usefulness of the system was demonstrated through a cultivation test involving several special plants.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.2
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• pp.306-324
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• 2009

The purpose of this study is to analyze green growth issues such as employment, education and training, social capital and nature's standing right from the complementary perspective between natural environment conservation and economic growth. Green growth can be defined as a growth which lowers an increasing rate of entropy and at the same time improves our living standard. Green growth paradigm requires a quite amount of understanding the laws of thermodynamics and the uncertainty principle as the highest orders which regulate our overall socio-economic behaviors. They suggest that socio-economic growth is a mere transformation process of natural energy from one form to another and they increases natural manmade entropy over time. The most important issue of green growth policy may be a problem concerning employment and/or unemployment since green growth may induce inevitable movement of resources from the existing industries to the green sector. In particular, green industries will demand more highly specialized manpower than the existing ones. Without a well-designed new training education system and social capital accumulation toward environmental concerns, green growth may accompany a substantial amount of structural involuntary frictional unemployment. This may increase not only wealth-distribution disparity but also political instability. In order to achieve harmonious green growth, we should recognize that there are important complementary relationships between green and growth. Our society should also be able to innovate the existing educational system to accumulate social capital, to create a new sharing system, and to admit nature's standing right. Although the 2003 lawsuit case of Korean Salamander in Cheonseong Mountain went against plaintiff, it would provide apparently our society with a way of green development ahead.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.501-506
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• 2001

The creep crack growth properties in 3.5NiCrMoV steel were investigated at $550^{\circ}C$ by using CT specimen under constant $C_t$ condition that was held during crack growth of 1mm distance. $C_t$ lely on load line displacement rate and $C^*$ usually increase with crack length though load is reduced in order to maintain constant $C_t$ value as crack growth. Fully coalesced area(FCA) ahead of crack tip tend to increase as $C_t$ increase to the critical value, and after that value FCA decrease. For the tertiary creep stage of crack growth test, the most of displacement is due to the steady state creep, except only small part due to the primary creep and other effects. Therefore, tests were mainly interrupted in the tertiary stage to obtain high value of $C_t$. At constant load and $C_t$ region, crack growth slope was 0.900 and 0.844 each, on the other hand $C^*$ slope was 0.480.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.167-176
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• 2020

The objective of the present study was to determine the best model to describe and quantify the changes in live body weight, height at withers, height at rump, body length and chest girth of Holstein cows raised under Korean feeding conditions for 50 months. The five standard growth models namely polynomial linear regression models, regression of growth variables on the first and second-order of ages in days (model 1) and regression of growth variables on age covariates from first to the third-order (model 2) as well as non-linear models were fitted and evaluated for representing growth pattern of Holstein cows raised in Korean feeding circumstances. Nonlinear models fitted were three exponential growth curve models; Brody, Gompertz, and von Bertalanffy functional models. For this purpose, a total of 22 Holstein cows raised in Korea used in the period from April 2016 to May 2020. Each model fitted to monthly growth curve records of dairy cows by using PROC NLIN procedure in SAS program. On the basis of the results, nonlinear models showed the lower root mean square of error (RMSE) for live body weight, height at withers, height at rump, body length and chest girth (12.22, 1.95, 1.55, 4.04, 2.06) with higher correlation coefficiency (R²) values for live body weight, height at withers, height at rump, body length and chest girth (0.99, 0.99, 0.99, 1.00, 1.00). Overall, the evaluation of the different growth models indicated that the Gompertz model used in the study seemed to be the most appropriate one for standard growth of Holstein cows raised under Korean feeding system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.2
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• pp.154-161
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• 2014

The purpose of this study is to evaluate the antioxidant activity and hair growth effects of a natural herbal ethanol extract, Samhwang-Sasimtang(SS). In case of antioxidant ability of SS, the content of phenolic compounds was 28.44mg/g. The extract showed strong electron donating ability and free radical scavenging activity in a concentration-dependent manner. SOD-like activity also rose through increasing the concentrations of SS. In order to estimate the hair growth effects, the extract was applied to the back of seven-week-old C57BL/6 male mice ($150{\mu}{\ell}$ a day, five days a week, for four weeks) in four groups (C, control, saline; PC, positive control, 3% minoxidil; E1, experimental 1, 1% SS; E2, experimental 2, 2% SS). Ten mice were assigned to each group and five mice in each group were sacrificed at weeks 2 and 4, respectively. There was no a significant difference in body weight change among experimental groups. In macroscopic observation of hair growth at week 4, the scores of hair growth on the backs of mice were 80, 60, 40 and 20% in the PC, E2, E1 and C groups. In terms of histological observation, the ratio and thickness of hair follicles, the enzyme activities of ALP and ${\gamma}$-GT, immunohistological examination of IGF-1 and VEGF which are the hair growth factors, in each group were significantly high in this order: PC, E2, E1 and C group, at week 4. Meanwhile, hair growth inhibition factors, TGF-${\beta}1$ and Caspase-3, were reduced in PC, E1 and E2 groups compared with C group. These results indicate that SS extract may be effective in promoting hair growth, and suggest that it can be used practically as a superior natural agent for hair growth promotion.