• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.1 s.173
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• pp.156-162
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• 2000

Sensitized STS 304 stainless steel crack growth rate(CGR) in high temperature water was investigated under trapezoidal wave loading test using fracture mechanics techniques. The CGR, due to stress corrosion cracking(SCC), were systematically measured as a function of the stress intensity factor and stress. holding time under trapezoidal wave loading. In high temperature water, CGR was enhanced by a synergistic effects in combination with an aggressive environment and mechanical damage. The CGR, $(da/dN)_{env}$ was basically described as a summation of the environmentally assisted crack growth rate $(da/dN)_{SCC}$, $(da/dN)_{CF}$ and fatigue crack growth rate in air $(da/dN)air,. The CGR, $(da/dN)_{env}$, increased linearly with increasing stress holding time. The CGR, $(da/dN)_{SCC}$ decreased linearly with increasing stress holding time. Fracture surface mode varied from trans-granular cracking to inter-granular cracking with increasing stress holding time.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.61-70
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• 2000

This study was carried out to improve the tobacco field condition and to determine the effect of lime amount and application time on soil pH, yield, and quality of leaf tobacco. Lime was applied to the tobacco field by determined amounts according to different pH level. The changes of soil pH, growth of tobacco, yield, and quality of KF109 and Br21 tobacco were surveyed by time lapse. The target pH value in tobacco field soil can be reached at 6 weeks after lime application, and then the soil pH was lowered slightly after that time. The lime amount needed to reach target pH was decreased 40 % in the same tobacco field after 1 year. Though the initial growth rate of flue-cured tobacco in the field of pH 7.0 was lower than that of conventional tobacco field, the field of pH 7.0 showed the highest yield after the maximum growth stage. The quality of cured leaf tobacco in the field of pH 7.0 applied lime at spring season was slightly lowered compared with that in conventional. This results indicated that the best pH condition in tobacco field for the best tobacco growth was 6.5 and the proper time of lime application was fall season of previous year by application of the whole quantity.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.49-54
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• 1998

The growth of diamond films in plasma enhanced chemical vapor deposition(PECVD) processes requires high substrate temperatures and gas pressures, as well as high-power excitation of the gas source. Thus determining the substrate temperature in this severe environment is a challenge. The issue is a critical one since substrate temperature is a key parameter for understanding and optimizing diamond film growth. The precise Si substrate temperature calibration based on rapid-scanning spectroscopic ellipsometry have been developed and utilized. Using the true temperature of the top 200 ${\AA}$ of the Si substrate under diamond growth conditions, real time spectroellipsometry (RTSE) has been performed during the nucleation and growth of nanocrystallind thin films prepared by PECVD. RTSE shows that a significant volume fraction of nondiamond(or{{{{ {sp }^{2 } -bonded}}}}) carbon forms during thin film coalescence and is trapped near the substrate interface between ∼300 ${\AA}$ diamond nuclei.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.382-385
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• 2000

A mathematical model was developed, based on the time dependent changes of the specific growth rate, for prediction of the typical microbial cell growth in batch cultures. This model could predict both the lag growth phase and the stationary growth phase of batch cultures, and it was tested with the batch growth of Trichoderma reesei and Lactobacillus delbrueckii.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.1-5
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• 2005

Eight flavonoids, apigenin-6-C-β-D-glucopyranosy l-8-C-β-D-glucopyranoside (AGG), quercetin 7-O-β-D­glucopyranoside (QG), luteolin 7-O-β-D-glucopyranoside (LG), quercetin 7-O-(6'-O-acetyl)-β-D-glucopyranoside (QAG), luteolin 7-O-(6'-O-acetyl)-β-D-glucopyranoside(LAG), quercetin (Q), luteolin (L) and acacetin 7-O-β­D-glucuronide (AG) were determined by HPLC in the safflower (Carthamus tinctorius L.) leaf during growth and processing. During growth, levels of five flavonoid glycosides (AGG, QG, LG, QAG, & LAG) in the leaf increased progressively at over time according to growth stages, reached a maximum before June 11, and then decreased sharply, while those of three flavonoid aglycones (Q, L, & AG) increased greatly at the early stage of growth, reached a peak before May 28, and then decreased rapidly. During the steaming process, contents of five flavonoid glycosides increased rapidly with increased steaming time, reached a maximum after 5 min of steaming, and then decreased, whereas those of flavonoid aglycones except for AG decreased sharply with increased steaming time. During the roasting process, contents of three flavonoid glycosides decreased rapidly with increased roasting time, whereas those of two acetylflavonoid glycosides (QAG & LAG) and three flavonoid aglycones increased progressively with increased roasting time, reached a maximum after 3 min of roasting, and then decreased. These results suggest that appropriate steamed and roasted safflower leaves are a rich source of flavonoids, and may be a good source of bioactive components as a functional leaf tea.

• The Korean Journal of Malacology
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• v.15 no.1
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• pp.41-47
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• 1999

From September 1994 to April 1996, we observed the suspending time dependant meat increase (dry weight) for oysters at Pukman Bay in Korea. The oysters which suspended in September increased to 5 g in meat weight (dry weight) by January. Ones in June increased rapidly but lessened during summer and this stagnation of meat increase extended to autumn. It took long time to compensate for the loss of meat weight owing to spawning. Oysters suspended in July or August showed low growth or stagnation due to the high water temperature and spawning activities after suspending. However, meat weight showed sudden increasement after December and achieved 5 g at the late farm period. The meat increase of oysters suspended in October or November was very slow during entire growing period. Most of them did not achieved 5 g during farm period. The negative correlation was observed between meat growth and water temperature in September. Also, there was a high correlation between meat growth and chlorophyll-a. It was believed that deficiency of food organisms in the water column lead slow growth in terms of meat growth, particularly right after transplanting seed oysters to the farm. Our study suggests that proper time for transplanting oysters is between August and mid-September. However, the data indicate that good growth of oysters is depending upon amount of food available in the water column.

• Transactions on Electrical and Electronic Materials
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• v.16 no.4
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• pp.198-200
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• 2015

The microwave plasma enhanced chemical vapor deposition (PECVD) system was used to grow a carbon nanowall (CNW) on a silicon (Si) substrate with hydrogen (H₂) and methane (CH₄) gases. To find the growth mechanism of CNW, we increased the growth time of CNW from 5 to 30 min. The vertical and surficial conditions of the grown CNWs according to growth time were characterized by field emission scanning electron microscopy (FE-SEM). Energy dispersive spectroscopy (EDS) measurements showed that the CNWs consisted solely of carbon.

• Journal of the Korean Vacuum Society
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• v.4 no.S1
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• pp.97-101
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• 1995

We report the results of a real-time synchrotron x-ray scattering study of the growth of TiN thin films on Si(001) substrates by RF sputtering. Our experiemnts show that the morphology of the TiN films strongly depends on growth conditions. After the nucleation and growth takes place with random crystallographic orientation at the very early stage, the films grow with a preferred orientation. Such preferred orientation was found to depend on both the sputtering power and the carrier gases used in the sputtering. Generally, the final morphology assumes either(111) or (002) crystallographic orientation. Using Ar sputtering, a cross-over effect from(002) to (111) was observed at intermediate time. The nature of the observed morphological changes is discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1291-1298
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• 2010

The aim of this research was to investigate the dynamic changes of the level of total prolactin receptor (PRLR) mRNA and the short form prolactin receptor (S-PRLR) mRNA in skin of cashmere goats from the initiation of cashmere fibre growth to active growth. Eighteen half-sib wethers were allocated randomly to two groups. Melatonin implants were used in order to initiate growth of cashmere fibre before the normal time and reduce blood plasma prolactin (PRL) concentration. Real-time reverse transcription quantitative polymerase chain reaction (real-time PCR) was used to determine PRLR mRNA expression levels of skin from June to November. The results showed that, in Chinese Inner Mongolia cashmere goats, there were seasonal variations in expression of total PRLR mRNA in skin with levels decreasing from June to October. Synchronously, the cashmere fibre growth rate gradually increased during this period, but the expression levels of S-PRLR mRNA did not decrease along with seasonal variation from initiation to active growth of cashmere fibre. These results suggest that expression levels of S- PRLR mRNA might be involved in the process of cashmere growth. It was also possible that the change of alternative splicing of PRLR occurred in the skin of cashmere goats from proanagen to anagen.

• Journal of Society of Preventive Korean Medicine
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• v.14 no.3
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• pp.107-115
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• 2010

Objectives : The purpose of this study is to investigate the efficacy of growth exercise program based on Korean medicine. Methods : We recruited fifty two elementary students in a rural area, and measured height, weight, BMI, WHR, and bone age. Questionnaire on sleep, exercise, symptoms based on Korean medicine was performed. Students exercised TaeGuk(太極) Health Gigong(氣功), a growth exercise program 11 times in 6 weeks. Results : Height, weight, BMI and WHR of the subject students were lower than those in the Korean CDC(Center for Disease Control and Prevention) growth chart. There was significantly negative correlation between time of sleep and bone age(p=0.028), but no correlation between time of exercise and bone age(p=0.668). According to diagnosis based on Korean medicine, many students were in weakness of spleen and lung, and bone age according to deficiency of organ showed no significant difference(p=0.774). Satisfaction, impact on time of exercise after program, ideal time for program and impact on reparticipation of program were strong in the questionnaire after growth exercise program(TaeGuk(太極) Health Gigong(氣功)). Conclusions : Korean medicine promotion of health has a salutary effect on elementary school students in rural area by collecting growth and health data and educating easy exercise based on Taichi.