• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1999.11a
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• pp.216-221
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• 1999

A mental task combined with noise background is an effective model of laboratory stress for study of psychophysiology of the autonomic nervous system (ANS). The intensity of the background noise significantly affects both a subjective evaluation of experienced stress level during test and the physiological responses associated with mental load in noisy environments. Providing tests of similar difficulties we manipulated the background noise intensity as a main factor influencing a psychophysiological outcome and the analyzed reactivity along withe the noise intensity dimension. The goal of this study was to identify the patterns of ANS responses and the relevant subjective stress scores during performance of word recognition tasks on the background of white noise (WN) of the different intensities (55, 70 and 85 dB). Subjects were 27 college students (19-24 years old). BIOPAC, Grass Neurodata System and AcqKnowlwdge 3.5 software were used to record ECG, PPG, SCL, skin temperature, and respiration. Experimental manipulations were effective in producing subjective and physiological responses usually associated with stress. The results suggested that the following potential autonomic mechanisms might be involved in the mediation of the observed physiological responses: A sympathetic activation with parasympathetic withdrawal during mild 55 and 70dB noise (featured by similar profiles) and simultaneous activation of sympathetic and parasympathetic systems during intense 85dB WN. The parasympathetic activation in this case might be a compensatory effect directed to prevent sympathetic domination and to maintain optimal arousal state for the successful performance on mental stress task. It should be mentioned that obtained results partially support Gellhorn's (1960; 1970) "tuning phenomenon" as a possible mechanism underlying stress response.

• Journal of the Korean Geotechnical Society
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• v.22 no.4
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• pp.61-71
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• 2006

A numerical procedure is presented fur evaluating seismic liquefaction on sloping ground sites. The procedure uses a fully coupled dynamic effective stress analysis with a plastic constitutive model called UBCSAND. The model was first calibrated against laboratory element behavior. This involved cyclic simple shear tests performed on loose sand with and without initial static shear stress. The numerical procedure is then verified by predicting a centrifuge test with a slope performed on loose Fraser River sand. The predicted excess pore pressures, accelerations and displacements are compared with the measurements. The results are shown to be in good agreement. The shear stress reversal patterns depend on static and cyclic shear stress levels and are shown to play a key role in evaluating liquefaction response in sloping ground sites. The sand near the slope has low effective confining stress and dilates more. When no stress reversals occur, the sand behaves in a stiffer manner that curtails the accumulated downslope displacements. The numerical procedure using UBCSAND can serve as a guide for design of new soil structures or retrofit of existing ones.

• Journal of Families and Better Life
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• v.26 no.6
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• pp.107-121
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• 2008

This study aimed to examine the effects of ego-resilience and social support on parenting stress perceived by mothers of school-aged children. The effects of demographic variables(including school grades of children) on the mothers' parenting stress were also investigated. The main results were as follows. First, ego-resilience of mothers was found to have the greatest predictive power on mothers' parenting stress. The more ego-resilient the mothers were, the less parenting stress was perceived. Second, social support also played an important role in alleviating maternal parenting stress. Emotional support of spouses was particularly effective in reducing mothers' parenting stress. Third, the only demographic variable that influenced mothers' parenting stress was their children's academic achievements. Finally, mothers perceived high parenting stress in relation to their children's school grades, while they perceived relatively less parenting stress concerning their children's temperament or the relationship with their children. The implications of these results were discussed.

• Journal of Korean Academy of Nursing Administration
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• v.17 no.4
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• pp.508-515
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• 2011

Purpose: The purposes of this study were to understand correlation of parenting stress and turnover intention of nurses, and to provide basic data for effective nursing management. Methods: Subjects included 287 nurses who had children and worked in hospitals. Data were collected through organized questionnaires from September 1st to 30th 2010. Collected data was analyzed with descriptive statistics, t-test, ANOVA, correlation analysis using PASW statistics 18 program. Results: The average score for parenting stress of the participants was 3.12 out of 5. Nurture stress was statistically different depending on age, job position, shift work, night duty and stages of family development. The average score for turnover intention of the participants was 3.34 out of 5. Turnover intention was statistically different depending on age, number of children and stages of family development. As a result of correlation analysis of parenting stress and turnover intention, turnover intention showed positive correlation with daily stress, stress caused from taking parent role and average parenting stress. Conclusion: This study indicates that parenting stress is related with turnover intention, nursing managers should make efforts to decrease parenting stress in order to reduce turnover intention of nurses.

• Journal of Korean Academy of Nursing
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• v.42 no.2
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• pp.161-170
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• 2012

Purpose: Purpose of this study was to examine the effects of the Mindfulness Meditation program on perceived stress, ways of coping, salivary cortisol level, and psychological stress response in patients with breast cancer. Methods: This was a quasiexperimental study with a non-equivalent control group pre-post test design. Participants in this study were 50 patients who had completed breast cancer treatment (experimental group, 25, control group, 25). The experimental group received the Mindfulness Meditation program for 3 hours/session/ week for 8 weeks. Data were analyzed using $X^2$-test and t-test for subject homogeneity verification, and ANCOVA to examine the hypotheses. Results: The experimental group had significantly lower scores for perceived stress, emotional focused coping, salivary cortisol level, and psychological stress response compared to the control group. However, no significant differences were found between two groups for the scores on problem focused stress coping. Conclusion: According to the results, the Mindfulness Meditation program was useful for decreasing perceived stress, emotional focused coping, salivary cortisol level, and psychological stress response. Therefore, this program is an effective nursing intervention to decrease stress in patients with breast cancer.

• The Journal of the Korea Contents Association
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• v.17 no.9
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• pp.466-475
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• 2017

Various factors in daily life cause stress, which could stem from trivial or major events. Stress is not appeared at any time but is appeared over the lifetime. Therefore, it is necessary to conduct studies to identify ways to manage stress. In the present study, we developed an iris analysis-based system to diagnose and manage stress. By analyzing its correlation with the degree of stress measured using the iris diagnosis and a questionnaire, the user's degree of stress quantitates. The system proposed in this study can be used to measure the degree of stress experienced by the user, which can be an effective method for the early diagnosis and prevention of stress-related diseases.

• YAKHAK HOEJI
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• v.44 no.1
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• pp.9-15
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• 2000

Four 3-alkoxy-6-allylthiopyridazines and 3-chloro-6-allylthiopyridazine were synthesized and their protective effects against oxidative stress and UV-C irradiation were tested. 3-Methoxy-6-allylthiopyridazine and 3-ethoxy-6-allylthiopyridazine did not show protective effect on the oxidative stress but showed the strongest protective effect on UV-C irradiation among the tested compounds. Especially 500 $\mu\textrm{g}$/$m\ell$ of the two compounds was the most effective concentration.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1998.03a
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• pp.178-183
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• 1998

This paper examines the crack growth behavior of 7075-T651 and 5052-H32 aluminum alloys for variable load within tensile load range condition. The cantilever beam type specimen with a chevron notch is used in this study. The crack growth and closure are investgated by compliance method. The applied initial stress ratio is R=0.3 and variable load are R=0.65, 0.46. Crack length, stress intensity factor range, ratio of effective stress intensity factor range and crack growth rate etc. are inspected with fracture mechanics estimate.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.300-305
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• 1996

Reinforced concrete column is an effective structural element to take advantage of high strength concrete. This paper presents an experimental and analytical strength of high strength concrete rectangular tied column sections under eccentric loading. The test variables are concrete strength, steel ratios, slenderness and eccentricity. The analytical results of the ACI's rectangular stress block, Zia's modified rectangular stress block, and a trapezoid block are compared with experimentally obtained data. It may be concluded that the trapezoid stress block provided the most reasonable column section capacities for high strength concrete columns.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.73-74
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• 2017

In this study, unlike high flowing concrete, using glass bubble to develop self-compacting concrete(hereinafter referred to as "SCC") with excellent filler performance by evaluating both flowability and yield stress, viscosity An experiment was conducted. Experimental results show that when 1 kg of glass bubbles are used, it is effective in stabilizing the physical properties of concrete, reducing the yield stress and viscosity.