• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.2
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• pp.116-122
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• 2002

Dehydrins (LEA Dll proteins) are one of the typical families of plant proteins that accumulate in response to dehydration, cold stress, abscisic acid, or during seed maturation. A 1.3-kb cDNA was cloned from a cDNA expression library of 5-day-old germinating maize scutellums under drought stress. The deduced protein sequence indicated a dehydrin gene encoding SK$_3$ LEA protein typically expressed during cold acclimation, but not by drought stress in barley and wheat. Thus, it was named maize DEHYDRIN2 (ZmDhn2). It accumulates rapidly and highly in drought-stressed scutellum and leaf tissues at any stage, but not under cold stress. ZmDhn2 gene was transformed into Arabidopsis thaliana for functional analysis under drought condition. From electrolyte leakage test, no significant difference showed between wild type and transformants under normal growth condition, but the leakage level of electrolyte in wild type plants was about 3 times as high as that in the transformed plants under drought stress. It suggests that ZmDHN2 playa role in increasing drought tolerance.

• Proceedings of the KIEE Conference
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• 2006.07e
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• pp.23-24
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• 2006

Stator winding of hydro generator is gradually deteriorated by multi-stress and steady degradation of insulation results in insulation breakdown. The region where insulation breakdown occurs in stator winding is part where the multi-stress causes the defect of insulation material and electrical stress has been concentrated. Therefore, we judged locations of insulation breakdown to be varied according to various stress factors in service. In this paper, we drew the stator winding of hydro generators which has run for a long time and separated it into 3 parts(central part, end winding part, drawing part) according to the positions laid on the core. We performed electrical and thermal stress on these specimens for 1000 hrs under the same condition, measured the condition regularlyand analyzed the insulation status of each winding by performing partial discharge test. In addition, we analyzed the trend of partial discharge concerning specimens that caused the insulation breakdown during aging.

• Journal of Wellness
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• v.6 no.2
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• pp.139-147
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• 2011

The purpose of this study was to examine the relationship between stress and leisure satisfaction of college student athletes. The participants comprised 140 of the college student athletes. The measures were composed of stress inventory and leisure satisfaction scale. The data were analyzed by SPSS 17.0 Version frequency analysis, reliability analysis, confirmatory factor analysis, independent sample t-test, one-way ANOVA, and multiple regression analysis were performed. The level of significance was set up .05. The results were as follows: First, according to college, there was significant difference in economic burden, environmental condition, and course factor. Second, in regard with multiple regression analysis on relationships between the stress and leisure satisfaction of the college student athletes, discriminative evaluation, environmental condition, and course factor had positive effect on leisure satisfaction.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.3
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• pp.240-246
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• 2019

The aim of this study was to investigate effect of heat stress on expression levels of plasminogen activators (PAs) related mRNAs and proteins, and changes of PAs activity in porcine endometrial explants. The endometrial explants (200 ± 50 mg) were isolated from middle part of uterine horn at follicular phase (Day 19-21) and were pre-incubated in serum-free culture medium at 38.5℃ in 5% CO₂ for 18 h. Then, the tissues were transferred into fresh medium and were cultured at different temperature (38.5, 39.5, 40.5 or 41.5℃) for 24 h. The expression level of urokinase-type PA (uPA), type-1 PA inhibitor (PAI-1), type-2 PAI (PAI-2), and heat shock protein-90 (HSP-90) mRNA were analysis by reverse-transcription PCR and proteins were measured by western blotting. The supernatant were used for measurement of PAs activity. In results, mRNA and protein levels of HSP-90 was higher in 41.5℃ treatment groups than other treatment groups (p < 0.05). The expression of uPA, PAI-1, and PAI-2 mRNA were slightly increased by heat stress, however, there were no significant difference. Heat stress condition suppressed expression of active uPA and PAI-2 proteins (p < 0.05), whereas PAI-1 protein was increased (p < 0.01). Although PAI-1 protein was increased and active uPA was decreased, PAs activity was greatly enhanced by exposure of heat stress (p < 0.05). These results suggest that heat stress condition could change intrauterine microenvironment through regulation of PAs activity and other factors regarding with activation of PAs might be regulate by heat stress. Therefore, more studies regarding with regulatory mechanism of PAs activation are needed.

• Journal of Korean Academy of Nursing
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• v.19 no.1
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• pp.99-107
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• 1989

This study explored differences in how medical and surgical patients compare on the degree of hospital stress and their subjective physical status. Subjects were 343 medical and surgical patients in five university hospitals in Seoul and Taegu. They responded to the Hospital Stress Rating Scale and a self-report on physical status. The controlled variables were age, education, number of previous hospitalizations and seriousness of the illness. Medical and surgical patient differences on nine factors of the hospital stres scale and nine areas of physical conditions were reported as follows edplored : 1. 1) There was not a statistically significant difference at the .05 level in the total mean score for hospital stress between medical patients and surgical patients. 2) The mean score of the factor lack of information (M＝2.308) for medical patients was higher than the mean score (M＝2.064) of the surgical patients. 3) The mean scores of the factor of discomfort (M＝2.130), loss of independence (M＝1.889) for surgical patients were higher than for medical patients. 2. 1) There was a statistically significant difference at the .05 level in the total mean score for physical status between medical patients and surgical patients. 2) The mean scores were lower in subjective physical status for surgical patients(S) than for medical patients (M) ; stomach condition (S : M＝2.8433, M : M＝3.0-000), self-assistance(S : M＝3.0373, M : M＝3.4498), movement (S : M＝2.6716, M : M＝3.2392), interest in your surroundings (S : M＝3.0522, M : M＝3.2632). 3. Patients scoring high on the subjective physical status such as sleep, appetite, stomach condition bowel condition and urination states had higher scores in hospital stress than with patients scoring low on those subjective Physical status. The results suggest that subjective physical status might be on expression of hospital stress. Also patients with high scores in subjective physical statas might be predicted have a high level of stress on admission. And surgical patients had a higher level of hospital stress than medical patients.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2536-2538
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• 1998

This paper investigates the residual stress of tetraethoxysilane (TEOS) and 7wt% phosphosilicate glass (PSG), which are commonly used as a sacrificial layer or etch mask in the fabrication of microelectromechanical systems (MEMS). In order to measure residual stress, $2{\mu}m$ thick TEOS and PSG stress measurement structures are fabricated. Polysilicon is used as the sacrificial layer. First the residual stress of an as-deposited 7wt% PSG flim and TEOS film are measured to be-0.3115% and -0.435%, respectively, which are quite large. These films are annealed from $500^{\circ}C$ to $800^{\circ}C$. Annealing has the effects of reducing residual stress. In the case of the 7wt% PSG film, the residual stress becomes +0.00715% after annealing at $625^{\circ}C$ for 150 minutes. In the case of TEOS film, the residual stress reduces to -0.2134% after same condition. Incidentally, this condition is the same condition for depositing a $2{\mu}m$ thick polysilicon at $625^{\circ}C$ at our low pressure chemical vapor deposition (LPCVD) furnace.

• Journal of Oriental Neuropsychiatry
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• v.6 no.1
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• pp.71-84
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• 1995

This paper is for studying interrelation between Stress perception, Todai Index(THI) test and coffee. this study was done on 163 college women whose ages were 18 to 33 and who were in University in Wonju. The Stress perception test and THI test shows the following results. 1. The Stress test on the group that drunk coffee and beverage shows high degree of oppression sense about school and daily life. 2.The total THI test on the group that drunk coffee shows high degree of complaint on mouth, evacuation and lie scale, but shows the lowest piont on nervousrness. 3. The D-group womrn who drink a cup of coffee, two or three show the highest complaint on mouth and evacuation. E-group shows the lowest lie scale. 4 The Stress test and health examination on the group that drunk coffee show high degee of stress. And it also shows stimulative relation between the condition of body health and drinking coffee. The above shows that coffee and some beverage can affect on mental and physical health. Especially they are considered as a factor of stimulus on stress response. Through the THI test, the effect on mouth and evacuation, lie scale and nervousness could be obseved. So the drinking coffee and beverage requires circumspection.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.5
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• pp.42-50
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• 1991

According as the members and inner and outer plates of the automobile body structure have been thinned their thickness and have become high strength, each part of the body structure has been put more severe stress condition. Therefore, it has been increasingly required to improve the fatigue strength of the spot welded structures. As one of the improving methods for such problem, the author had previously proposed the method of alleviating stress concentration at nugget edge of the spot weld part and improving its fatigue strength [1]. But, because fatigue strength of the spot welded lap joint is influenced by its geometrical and mechanical factors, welding condition and etc., there needs a quantitative and systematic estimation method of them. In this report, by considering nugget edge of the spot weld part of the spot welded lap joint subjected to tensile load to the ligament crack, fatigue strength of various spot welded lap joints was estimated with the stress intensity factor (S.I.F.) K which is fracture mechanical parameter. It is known that evaluation of fatigue strength of the spot welded lap joint by the stress intensity factor (S.I.F.) K is more effective than the maximum stress $(\sigma_{ymax}$) at edge of the spot weld part on the center line of width of the plate.

• Journal of Ocean Engineering and Technology
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• v.2 no.2
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• pp.96-103
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• 1988

The stress distribution in the vicinity of the crack tip in the fracture mechanics is ordenarily indicated by the stress intensity factor. In the analysis of stress intensity factors, there are many theoretical and experimental methods. The stress analysis in photoelastic technique is usually made by using the difference of the principal stress of isochromatic fringe patterns. In this paper, the teflon molding technique is adopted to make a test specimen with a circular arc-crack, and that upgraded the accuracy of experiment. As the result, the experimental values of the stress intensity factors for the circular disk with a straight crack are coincided with the theoretical values. But, there is quite a difference between this expermental results on the finite plate for circular arc-crack and its theoretical values on the infinite one. Therefore, a boundary condition with regard to the loading condition on finite disk must be considered.

• Tribology and Lubricants
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• v.20 no.4
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• pp.190-196
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• 2004

The effect of tangential loading on the subsurface stress field has been investigated numerically. As tangential load increases, the subsurface stress field expands more widely to the direction of the tangential load. Places of the maximum shear stress and the maximum effective stress are getting closer to the surface with the increasing tangential load. The tangential load in an elasto-hydrodynamic lubrication condition is so low that it does not affect the subsurface stress field.