• Proceedings of the KSR Conference
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• 2001.05a
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• pp.249-256
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• 2001

This study investigated the shear stiffness of level of small strain with time effect. Time effect consists of rest time, loading rate of recent and current stress path. In addition, for the measurement of small strain, overconsolidated state was represented in a triaxial cell, and drained stress path tests were carried out. Test results show that the loading rate of recent stress path has no effects on the stiffness of very small strain, but the shear stiffness of level of small strain increases with it. Finally, the rest time and the loading rate of current stress path have the effects on the shear stiffness of initial and small strain.

• Computational Structural Engineering
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• v.8 no.1
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• pp.137-146
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• 1995

Structural stress under shock or impact load is varied with the lapse of time and the structural stress is called stress wave. Propagating longitudinal stress wave is studied in a 2-dimensional plate. A finite element program for elastic stress wave propagation is developed in order to investigate the shape of stress field at time increment. The longitudinal stress wave is generated by unit step function. According to the finite element analysis results, the longitudinal stress wave propagates to the similar direction of impact load and the front of stress wave propagates with the same speed as analytic solution and the shape of stress field is similar to that of analytic solution. The shear wave is occurred after the longitudinal stress wave and declined at an angle of 45 degrees compared with longitudinal stress wave and the speed of shear wave is about a half of the longitudinal stress wave. The intensity of shear wave is larger than that of longitudinal stress wave.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.4
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• pp.134-153
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• 1988

This paper was carried out to investigate the existence of a unique stress- strain behavior by obtaining some factors influencing the time dependent stress- strain behavior of clay. The results obtained from this study were summarized as follows ; 1. The relationship between stress ratro and strain in normally consolidated clay was in- dependent on pre-shear consolidation pressure. Therefore, shear strain could be expressed as a function with stress ratio. 2. The constitutive equation of shear strain on Modified Carn Clay Model coincided better with the observed value than Cam Clay Model. 3. The relationships between deviator stress and shear strain, between pore water pressure and shear strain were unified by the mean equivalent pressure. 4. The shear strain contour in norrnally consolidated clay was increased linearly through origin, but that in overconsolidated clay was not in accordance with the result of the former. 5. Because the effective stress path of normally consolidated clay was unified by the mean equivalent pressure, state boundary surface in (e,p,q) space was transformed into two dimensional surface. But it was considered to be suitable that the unified stress- strain in overconsolidated clay be expressed by a function with overconsolidation ratio. 6. The deviator for constant strain was increased linearly with increment of strain rate ($\varepsilon$) on semi-log scale, but pore water pressure was decreased. 7. The behavior of stress relaxation was transformed from linear to curvilinear with inc - rement of strain rate before stress relaxation test, and pore water pressure was increased in total range. 8. The strain of creep was increased linearly with increment of time on semi-log scale. The greater the strain rate before creep test became, the greater the increment of strain of creep became. And the pore water pressure during creep test was increased generally with increment of time on semi-log scale.

• Journal of Korean Academy of Nursing Administration
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• v.16 no.4
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• pp.466-474
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• 2010

Purpose: This study was done to identify the relationship between emotional intelligence (EI) and job stress of clinical nurses in small to medium-sized hospitals. Methods: Data were collected from a convenience sample of 152 nurses working in 4 local public hospitals in one district. EI was measured with the scale developed by Law, Wong, & Song (2004), and job stress with the scale by Choi, Kang, & Woo (2006). Data were analyzed with PASW (SPSS) 18.0, using descriptive statistics, t-test, ANOVA, Scheffe' test, Pearson correlation coefficients, and multiple regression. Results: There were significant differences in EI according to work time, in self-emotional appraisal according to salary, in regulation of emotion according to marital status, age, work time, and salary. There were also significant differences in job stress including somatization, depression and anger according to marital status, work time, and salary. Correlation between EI and job stress was negative. EI explained 17.3% of variance in job stress. Conclusion: The findings indicate that to decrease job stress, nursing managers need to develop EI, especially self-emotional appraisal and regulation of emotion for nurses in their twenties and for unmarried nurses.

• Journal of the Korean Society of Safety
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• v.32 no.4
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• pp.73-78
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• 2017

In this study, the risk level of architectural works was calculated by applying work period and number of input workers based on accidents records from 2012 to 2014 and the architectural works were divided into four groups(High-High, High-Low, Low-High, Low-Low) according to risk levels of fatal accidents and loss time accidents. And then questionnaire on the job stress level of workers was performed for 670 workers working in the architectural work using Korean Occupational Stress Questionnaire Form developed by KOSHA. And then the relationship between the risk level and job stress level of four groups was analyzed. Results showed that 1) risk levels of fatal and loss time accidents applied by work period and input workers were analyzed to be different with those of previous research based on the number of fatal and loss time accidents; 2) job stress level of workers has been analyzed to have a significant relationship with the risk level of fatal and loss time accident; 3) specially, the average of job stress level of 'HH(High-High)' group was higher than those of other groups; 4) among the subfactors of job stress, interpersonal conflict, job insecurity, organizational system and lack of reward were analyzed to be key factors to affect the risk level.

• Industry Promotion Research
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• v.9 no.2
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• pp.175-183
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• 2024

This study aims to provide basic data that can reduce the parenting stress of parents raising disabled children by verifying whether parenting time mediates the effect of parenting stress on mental health through parenting efficacy. The subjects of the survey were parents of disabled children, a total of 315 people. Data were analyzed using SPSS and SPSS PROCESS macro 4.2. Descriptive statistical analysis, reliability analysis, correlation analysis, and moderated mediation effect analysis were applied. The research results are as follows. First, the parenting stress of parents raising disabled children showed a positive correlation with parenting efficacy, a negative correlation between parenting stress and mental health, and a negative correlation between parenting efficacy and mental health. Second, parenting time moderated and mediated the effect of parenting stress on mental health through parenting efficacy. In conclusion, it was confirmed that the parenting time of parents raising disabled children plays a role in increasing the negative impact of parenting stress on mental health through parenting efficacy.

• Journal of Digital Convergence
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• v.11 no.10
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• pp.517-526
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• 2013

This study was conducted to investigate the effects of time management behavioral therapy program on self-esteem, stress coping of school maladjusted adolescents. Experiment was conducted with 8 school maladjusted adolescents who were helped in living facilities. Time management behavioral therapy was applied to adolescents 16 weeks. To achieve the purpose of this study, self-esteem scale and stress coping scale were analyzed and compared before and after intervention. The results of this study were as follows: School maladjusted adolescents showed the significant increase in self-esteem. and School maladjusted adolescents showed the significant increase in active and passive coping of stress by intervention. It was proven to have positive effects on stress coping by intervention in a short time. Through the results of this study, time management behavioral therapy program was proven to have positive effects on self-esteem, stress coping of school maladjusted adolescents.

• The Journal of Korean Academic Society of Nursing Education
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• v.15 no.2
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• pp.241-250
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• 2009

Purpose: The purpose of this study was to investigate the relationship of stress, perceived health status and Yangsaeng in Korean part-time college students. Yangsaeng is a traditional health care regimen that incorporates specific principles and methods to promote health and prevent illness, with the aim of improving the health and longevity of life. Method: The subjects of this study were 158 part-time college students in Korea. Data were collected by using a self-reported questionnaire on-line. Analysis of data included descriptive statistics, Pearson's correlation coefficient, t-test, ANOVA and Cronbach's $\alpha$. Result: Statistically significant differences were evident in stress according to age, spouse, job, and income. Statistically significant differences were evident in perceived health status according to gender and job. Statistically significant differences were evident in Yangsaeng according to age, job, and income. Yangsaeng positively related to perceived health status and negatively related to stress. Conclusion: The Yangsaeng oriental health care regimen could lower stress levels and maintain a good health perception. Therefore, Yangsaeng could be recommended as a means of health promotion in Korean part-time college students.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.9
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• pp.1614-1618
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• 2007

We have demonstrated the experimental results to obtain the immunity of FN (Fowler Nordheim) stress for S-RCAT (Spherical-Recess Cell Array Transistor) which has been employed to meet the requirements of data retention time and propagation delay time for sub-100-nm mobile DRAM (Dynamic Random Access Memory). Despite of the same S-RCAT structure, the immunity of FN stress of S-RCAT depends on the process condition of gate oxidation. The S-RCAT using DPN (decoupled plasma nitridation) process showed the different degradation of device properties after FN stress. This paper gives the mechanism of FN-stress degradation of S-RCAT and introduces the improved process to suppress the FN-stress degradation of mobile DRAM.

• Geomechanics and Engineering
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• v.32 no.5
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• pp.495-502
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• 2023

In this study, stress relaxation tests were carried out by keeping silt type soil specimens under different strain levels. Decreases in the stress values with time data was collected to better understand the effect of the strain level on the relaxation properties of soil specimens. In addition, the stress relaxation effect on the uniaxial compressive strength (UCS) values of the specimens was investigated with a series of tests. According to the results obtained from this study, the UCS values of the silt specimens significantly vary as a result of the stress relaxation effect. The UCS values were determined to increase with an increase of relaxation strain level to a threshold value. On the other hand, the UCS values were found to be affected adversely in case of high stress levels at the initiation of the relaxation, which are close to the peak level.