• The Korean Journal of Health Service Management
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• v.5 no.4
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• pp.81-93
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• 2011

The purpose of this study was to examine the stressors of students in high school. Demographic data such as jobs of parents, family types, levels of living (parents' monthly income) and students' school records, high school types, number of friends, religion, pocket money and their sex showed as the main causes of high school students' stress. The data was analyzed by a t-test, one-way ANOVA, and Duncan Multiple Range Test. The variable which significantly influenced the general properties was sex(p=0.001), high school type (p=0.000), number of friends (p=0.002), parents monthly income (p=0.011) and whether existence of their father or not (p=0.045). In the result (stress score), girl students (25.07) feel greater stress than boy students (20.68). High school type, an academic girls' high school (27.34) and boys' high school (25.67) showed the highest. It was indicated in the study that it is necessary to have programs that help students' stress management and improve high school type Systems.

• Journal of the Korean Graphic Arts Communication Society
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• v.27 no.1
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• pp.89-106
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• 2009

The purpose of this study is to provide necessity of job stress management to chief executives officers at small and medium size printing companies. At the same time, this study offers information of successful job stress management. When managing job stress is successfully accomplished, it increases job involvement of workers and brings high productivity eventually. Independent variables are decision-making right at the job, insecurity of job, and unreasonable reward at the company, while job involvement is dependent variable at this study. After analyzing data gathered, decision-making right influences job attachment and pursuing job outcome. And insecurity of job, that is the difficult job transferring, is significant to job accomplishment.

• Journal of Families and Better Life
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• v.11 no.1
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• pp.218-234
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• 1993

A study focused on the wives'managerial behavior and their life satisfaction according to wives'stress level ad their coping behavior. The statistical procedures used were percentile mean cronbach's a T-test F-test cluster analysis. Duncan's Multiple Range test. For the purpose the sample were conducted using questionnairs on 548 housewives that lived in seoul. The major findings wee ; 1) The wives's education level of background variables significantly was differentiated from wives' managerial behavior and their life satisfaction respectively. 2) The wives'stress level and their coping behavior respectively was higher than average. from wives'managerial behavior respectively. 4) The variable i.e. wives'stress level wives'coping behavior significantly was differentiate from wives'life satisfaction respectively In conclusion to improve wives'managerial behavior and their life satisfaction this study suggests we have to try to release or decrease wives'stress level and to do the resonable wives'co-ping behavior.

• Korean Journal of Child Studies
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• v.26 no.6
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• pp.393-409
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• 2005

This study examined effects of self-perceived obesity, peer victimization, stress, and maternal child rearing behaviors on self-esteem in an obese group(OG) and a normal weight group(NWG) of elementary school children. Subjects were 1,501 elementary school children in the 4th to the 6th grades in Seoul, Busan, Daegu, Gwangju, and Andong and their mothers. Major findings were that maternal child rearing behaviors and stress related to parents and home environments influenced children's self esteem only in the NWG; school-related stress was an influential variable on children's self esteem in both the NWG and OG. Peer victimization influenced children's self-esteem in both NWG and OG. Self-perceived obesity influenced some domains of children's self-esteem, especially in girls.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.547-553
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• 1990

With alumina ceramics to copper brazement of cylindrical shape, the thermal stress analysis was carried out by finite element method. Elastic and plastic behaviour was considered to copper, but only elastic behaviour was considered to alumina. Also material properties of alumina and copper were considered in not constant values but variable functions dependent on temperature. The result of analysis is shown that maximum tensile longitudinal stress is occurred at perimeter of alumina side interface and maximum compressive radial and tangential stresses are occurred at center of alumina side interface. Because of bending effect, tensile raidial and tangential stresses are occurred at near bottom of alumina, far from interface.

• Structural Engineering and Mechanics
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• v.58 no.4
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• pp.689-705
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• 2016

The Drucker-Prager yield criterion is combined with an equilibrium equation to provide the elastic-plastic stress distribution within rotating annular hyperbolic discs and the residual stress distribution when the angular speed becomes zero. It is verified that unloading is purely elastic for the range of parameters used in the present study. A numerical technique is only necessary to solve an ordinary differential equation. The primary objective of this paper is to examine the effect of the parameter that controls the deviation of the Drucker-Prager yield criterion from the von Mises yield criterion and the geometric parameter that controls the profile of hyperbolic discs on the stress distribution at loading and the residual stress distribution.

• Journal of Ocean Engineering and Technology
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• v.8 no.2
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• pp.115-123
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• 1994

Under variable amplitude loading conditions, retardation or accelerated condition of fatigue crack growth occurs with every cycle, Because fatigue crack growth behavior varied depend on load time history. The modeling of stress amplitude with storm loading acted to ships and offshore structures applied this paper. The crack closure behavior examine by recording the variation in load-strain relationship. By taking process mentioned above, fatigue crack growth rate, crack length, stress intensity factor, and crack closure stress intensity factor were obtained from the stress cycles of each type of storm ; A(6m), B(7m), C(8m), D(9m), E(11m) and F(15m) which was wave height. It showed that the good agreement with between the experiment results and simulation of storm loads. So this estimated method of crack propagtion rate gives a good criterion for the safe design of vessels and marine structure.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.1
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• pp.201-212
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• 2001

If defects are located far apart, fatigue cracks are independently initiated from them and gradually approach other cracks so that the fatigue life becomes influenced by the crack growth behavior of those interacting cracks. In this study, the effect of the stress interaction between defects on the fatigue crack propagation behavior is investigated experimentally and these results are verified by finite element method. In addition, fatigue crack propagation behaviors under micro hole interaction field are studied.

• Journal of Korean Foot and Ankle Society
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• v.25 no.1
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• pp.1-5
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• 2021

Physical examination and surgical findings and symptoms are often inconsistent with magnetic resonance imaging (MRI) findings when diagnosing chronic ankle lateral ligament instability, and confirmed surgical findings are used as the gold standard in most clinical studies. Anterior drawer testing is considered unreliable because normal findings are highly variable, and its accuracy ranges from 50% to 100%. Furthermore, radiographic stress imaging, such as in anterior drawer stress view, is performed under manual stress or using a stress device, and its findings also vary widely and confuse when interpreting stress views. The average accuracy of MRI findings is around 85% (range, 66%~91.7%), and thus, cannot be used as a primary indicator for surgery. For patients with suspected lateral ankle ligament instability, based on symptoms and physical examination findings, MRI may be useful for identifying lesions in ankle joints and for differentiating them from other conditions.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.6
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• pp.367-374
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• 2022

This papter presents the use of the automatic differential method based on the backpropagation method to obtain the design sensitivity and its application to topology optimization considering the stress constraints. Solving topology optimization problems with stress constraints is difficult owing to singularities, the local nature of stress constraints, and nonlinearity with respect to design variables. To solve the singularity problem, the stress relaxation technique is used, and p-norm for stress constraints is applied instead of local stresses for global stress measures. To overcome the nonlinearity of the design variables in stress constraint problems, it is important to analytically obtain the exact design sensitivity. In conventional topology optimization, design sensitivity is obtained efficiently and accurately using the adjoint variable method; however, obtaining the design sensitivity analytically and additionally solving the adjoint equation is difficult. To address this problem, the design sensitivity is obtained using a backpropagation technique that is used to determine optimal weights and biases in the artificial neural network, and it is applied to the topology optimization with the stress constraints. The backpropagation technique is used in automatic differentiation and can simplify the calculation of the design sensitivity for the objectives or constraint functions without complicated analytical derivations. In addition, the backpropagation process is more computationally efficient than solving adjoint equations in sensitivity calculations.