• Korean Journal of Psychosomatic Medicine
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• v.12 no.2
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• pp.135-144
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• 2004

Objectives: The aim of this study was to examine the effectiveness of a qigong-based stress management program in pregnant women. Method: A 8 week controlled clinical trial compared 52 pregnant women assigned qigong-based stress management program to 40 pregnant women assigned pregnancy health education program. Edinburgh postnatal depression scale(EPDS), Beck depression inventory(BDI), Spielberger trait state inventory-1(STAI-1), Hamilton depression rating scale(HAM-D), Hamilton anxiety scale(HAM-A) were used to measure anxiety and depression level. Result : Qigong-based stress management group showed significant improvement compared to the education control group on four measures above. Qigong-based stress management group also showed significant improvement at 8 weeks termination on all measures of anxiety and depression compared to pretreatment level. Conclusion : This study showed that qigong-based stress management program can be an effective method for pregnant women.

• Korean Journal of Child Studies
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• v.26 no.5
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• pp.245-261
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• 2005

This study examined the relationship between father's participation in child rearing and mother's schild rearing stress. Mothers of 450 4-, 5- and 6-year-old children in six different kindergartens and daycare centers in Seoul and Kyungki-do area completed the Father's Participation in Child Rearing(Kyung Soon Choi, 1993) scale and the Parenting Daily Hassles(Cmic & Greenberg, 1990) scale. Data were analyzed statistically by SPSS. Results show that higher father's participation in child rearing results in lower child rearing stress for mothers. Especially, father's participation in areas of parenting and housework is important factor influence mother's decrease child rearing stress.

• Structural Engineering and Mechanics
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• v.18 no.1
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• pp.113-124
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• 2004

The information on local stress acting in a bridge is required in many occasions such as fatigue assessment. The analysis by beam elements cannot yield this class of information adequately, while the finite element modeling of an entire long-span bridge by shell elements is impractical. In the present study, the hybrid modeling is tried out: only part of a bridge in which the point of interest is located is discretized by shell elements and the remaining part is modeled by beam elements. By solving a simple box girder problem, the effectiveness of this approach is discussed. This technique is then applied to the Rama IX Bridge for local stress evaluation. The numerical results compare very well with the results of a full-scale static loading test. The present research thus offers a practical yet accurate technique for the stress analysis of a long-span cable-stayed bridge.

• Korean Journal of Adult Nursing
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• v.15 no.4
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• pp.607-616
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• 2003

Purpose: The purpose of the study was to examine the relationships among social support (network, composition, and satisfaction), stress, and loneliness in migrant Yanbian Korean workers. Method: Data were collected by using Social Support Questionnaire 6, Visual Analogue Scale, and the Revised UCLA Loneliness Scale. Result: Results indicate that means for social support were 1.52 for network size and 4.83 for satisfaction. The proportion percentage of network for kin members was 67.37. Subjects felt the moderate level of stress and loneliness. The level of loneliness was negatively related to the level of social support. Conclusion: This study showed that there is necessity to reduce stress and loneliness among migrant Yanbian Korean workers. Adequate social support satisfaction is crucial to reduce the level of loneliness in migrant Yanbian Korean workers.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.4
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• pp.401-409
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• 2009

This paper presents a method of calculating the stress intensity factor (K) and crack propagation direction (${\theta}_0$) at the crack-tip that is associated with delamination in the large scale integration(LSI) package. To establish a reasonable strength evaluation method and life prediction, it is necessary to assess fracture parameters under various fracture conditions. Therefore, we conducted quantitative stress singularity analysis considering thermal stress simulating the changes of crack length (a), (h) and (v) in delamination using the 2-dimensional elastic boundary element method (BEM), and from these results predicted crack propagation direction and path.

• Journal of Mechanical Science and Technology
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• v.19 no.8
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• pp.1682-1691
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• 2005

Direct numerical simulation database of an axial turbulent boundary layer is used to compute frequency and wave number spectra of the wall shear-stress fluctuations in a low-Reynolds number axial turbulent boundary layer. One-dimensional and two-dimensional power spectra of flow variables are calculated and compared. At low wave numbers and frequencies, the power of streamwise shear stress is larger than that of spanwise shear stress, while the powers of both stresses are almost the same at high wave numbers and frequencies. The frequency/streamwise wave number spectra of the wall flow variables show that large-scale fluctuations to the rms value is largest for the stream wise shear stress, while that of small-scale fluctuations to the rms value is largest for pressure. In the two-point auto-correlations, negative correlation occurs in streamwise separations for pressure, and in span wise correlation for both shear stresses.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.404-408
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• 2005

The Reynolds strss equation with turbulent energy-length scales was simplified in the nearly homogeneous turbulent equilibrium flow and a modified Reynolds stress model was proposed. Tn the model proposed in the present study, Reynolds stresses can be expressed in the form of algebraic equation, so that the turbulent stresses and related quantities are calculated through relatively simple procedures. The model predicted well the turbulent shear stresses of homogeneous flow in local equilibrium state obtained from experimental results published earlier Constants used In the model was determined universally and its validity was discussed briefly.

• Steel and Composite Structures
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• v.26 no.1
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• pp.89-102
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• 2018

This work investigates a novel plate formulation and a modified couple stress theory that introduces a variable length scale parameter is presented to discuss the static and dynamic of functionally graded (FG) micro-plates. A new type of third-order shear deformation theory of Reddy that use only 4 unknowns by including undetermined integral variables is proposed in this study. The equations of motion are derived from Hamilton's principle. Analytical solutions are obtained for a simply supported micro-plate. Numerical examples are presented to examine the effect of the length scale parameter on the responses of micro-plates. The obtained results are compared with the previously published results to demonstrate the correctness of the present formulation.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.2
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• pp.186-191
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• 2001

A crack with electrically impermeable surfaces in an electrostrictive material subjected to uniform electric loading is analysed. The effect of electric yielding on stress intensity factor is investigated by using a small scale yielding model and a strip yield zone model. Complete forms of electric fields and elastic fields are derived by using complex function theory. The electrical yield zone shapes for two models are different each other. The two models, however, predict similar yield zone sizes under the small scale yielding conditions. It is found that the influence of electric yielding on the stress intensity factor is insensitive to the modeling of the electrical yield zone shape.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1997.10a
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• pp.16-23
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• 1997

The Reproducing Kernel Particle Method (RKPM), one of the popular meshless methods, is developed and applied to stress concentration problems. Since the meshless methods require only a set of particles (or nodes) and the description of boundaries in their formulation, the adaptivity can be implemented with much more ease than finite element method. In addition, due to its intrinsic property of multiresolution, the shape function of RKPM provides us a new criterion for adaptivity. Recently, this multiple scale Reproducing Kernel Particle Method and its adaptive procedure have been formulated for large deformation problems by the authors. They are also under development for damage materials and localization problems. In this paper the multiple scale RKPM for linear elasticity is presented and the adaptive procedure is applied to stress concentration problems. Therefore, this work may be regarded as the edition of linear elasticity in the complete framework of multiple scale RKPM and the associated adaptivity.