• Journal of East-West Nursing Research
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• v.18 no.2
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• pp.74-80
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• 2012

Purpose: The purpose of this study is to evaluate the effects of Lavender inhalation on sleep, depression and stress of institutionalized elderly. Methods: The methods used in the study follows a non-equivalent pre- and post-test design. 39 institutionalized elderly were recruited using a convenient sampling method that assigned them to the experimental or the control group. The experimental group were then provided with essential Lavender oil, as part of the aroma inhalation intervention, to inhale before sleeping for 7 days. The collected data were analysed with SPSS 18.0 (windows program), using frequency percentage (%), a Chi-square test and an independent t-test. Results: The results were that the experimental group had significantly higher sleep status scores(t=5.195, p=.000), and lower depression scores (t=-5.479, p=.000), physical stress scores (t=-5.741, p=.000) and psychological stress scores (t=-4.233, p=.000) than those in the control group. Conclusion: This study suggests that aroma inhalation, as part of aroma therapy, be applied and comprehensively adopted as a method of nursing intervention for improvement of sleep, depression and stress for institutionalized elderly.

• Fibers and Polymers
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• v.2 no.4
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• pp.203-211
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• 2001

Residual stresses were predicted by a flow analysis in the mold cavity and residual stress distribution in the injection molded product was measured. Flow field was analyzed by the hybrid FEM/FDM method, using the Hele Shaw approximation. The Modified Cross model was used to determine the dependence of the viscosity on the temperature and the shear rate. The specific volume of the polymer melt which varies with the pressure and temperature fields was calculated by the Tait\`s state equation. Flow analysis results such as pressure, temperature, and the location of the liquid-solid interface were used as the input of the stress analysis. In order to calculate more accurate gap-wise temperature field, a coordinate transformation technique was used. The residual stress distribution in the gap-wise temperature field, a coordinate transformation technique was used. The residual stress distribution in the gap-wise direction was predicted in two cases, the free quenching, under the assumption that the shrinkage of the injection molded product occurs within the mold cavity and that the solid polymer is elastic. Effects of the initial flow rate, packing pressure, and mold temperature on the residual stress distribution was discussed. Experimental results were also obtained by the layer removal method for molded polypropylene.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.11
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• pp.1813-1819
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• 2001

Partial penetration welding Joint defines that groove welds without steel backing, welded from on side, and groove weeds welded from both sides but without back gouging, that is. it has an unwelded portion at the root of the weld. In this study we analysed fur residual stress and displacement distribution on partial penetration welding condition of thick plate metal. For 25.4mm thick plate, theoretical residual stress and displacement analysis by finite element method using ABAQUS was carried out and compared with the experimental result using hole-drilling method. In results of the condition of partial penetration, it appeared that longitudinal stress at welding area was a little difference and transverse stress did not have any effect by partial penetration multi-pass welding. From a point of welding distortion in partial penetration multi-pass welding, it seemed to be better to control root face smaller than 6.35mm.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.359-370
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• 1993

Up to now, most studies are on interface crack problems in isotropic-isotropic dissimilar materials, but it seems to be not so much on anisotropic dissimlar materials. In this study, the stress intensity factors for an interface crack in anisotropic dissimilar materials are analysed using author's proposed extrapolation method by BEM and we have done a parametric study about material properties or shapes of crack affecting to the stress intensity factors. However, as there are not other's comparable numerical results on these anisotropic dissimilar materials to the best of author's knowledge, the reliability of the present results was proved by following two methods. The first is considering the asymptotic characteristic about stress intensity factors for an interface crack in anisotropic materials when the ansiotropic material approachs to the isotropic material. The second is considering the discontinuity of stress intensity factors between of a crack in an identical homogeneous anisotropic material and an interface crack in anisotropic dissimilar materials.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.917-925
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• 2022

Steam generator (SG) tubes in a nuclear power plant can undergo rapid changes in pressure and temperature during an accident; thus, an accurate model to predict short-term creep damage is essential. The theta (𝜃) projection method has been widely used for modeling creep-strain behavior under constant stress. However, many creep test data are obtained under constant load, so creep rupture behavior under a constant load cannot be accurately simulated due to the different stress conditions. This paper proposes a novel methodology to obtain the creep curve under constant stress using a modified 𝜃 projection method that considers the increase in true stress during creep deformation in a constant-load creep test. The methodology is validated using finite element analysis, and the limitations of the methodology are also discussed. The paper also proposes a creep-strain model for alloy 690 as an SG material and a novel creep hardening rule we call the damage-fraction hardening rule. The creep hardening rule is applied to evaluate the creep rupture behavior of SG tubes. The results of this study show its great potential to evaluate the rupture behavior of an SG tube governed by creep deformation.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.19 no.2
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• pp.140-145
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• 2023

When performing stress analysis for a nozzle in nuclear power plants, the nozzle loads should be determined conservatively. Existing stress analysis report of 3-D nozzle loads in nuclear power plants often provide only load magnitude not the sign (direction). Since calculated stress distribution depends on load direction, determining critical load directions for conservative stress analysis is crucial. In this study, an efficient method for determining critical load directions in nozzle loads is proposed. In the proposed method, stresses are firstly calculated using elastic finite element (FE) analysis for the uni-axial load in each direction. Then stress distributions for the multi-axial loads are analytically calculated using the principle of superposition. The calculated stress values are verified by comparing with FE analysis results under multi-axial loading. By using this method, the complex task of determining conservative load directions can be simplified.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.1
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• pp.26-39
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• 2003

The elderly can experience a lot of stressful events and the stress acts as a various fluent that affects a well-being level, the self-contentment of lives, and the achievements by themselves. Also, the elderly are different from the young in many unexpressed stress and have diverse copings for perceived stress. Moreover, they mainly seem to use a problem-focused coping and an emotion-focused coping. To use whatever copings is to improve the quality of life in the old period and very important fact to achieve their ends. The purpose of this study was to investigate the relationship between Perceived Stress and the Ways of Coping in the Elderly and to gain the baseline data for development of nursing intervention program for improve to the quality of life in the elderly. The design of this study was a correlational study. The subjects of this study consisted of 230 of the elderly living in Pusan. The data was collected from 1st July. to 1st September, 2002. The instruments used for this study were 'Perceived Stress Scale(20items, 5point. scale)' developed by Kang In(1990) and translated by Lee young-ja(1999), and its reliability is Cronbach's ${\alpha}=.89$. 'Coping Scale(30items, 4point. scale, 14 items about a problem-focused coping, 16 items about an emotion-focused coping, 4 points scale) developed by Lazarus & Folkman(1984) and translated by Yang Young-hee(1998). The reliability of this study is Cronbach's ${\alpha}=.90$. The data was analyzed by the SPSS WIN 10.0 program using frequency, percentage, mean, standard deviation, t-test, ANOVA & Scheffe test and Pearson's correlation coefficient. The results of this study were as follows; 1. The mean score of perceived stress was $31.75{\pm}10.23$(Min 20, Max 100), which the item mean score was $1.59{\pm}.51$(Min 1, Max 5). 2. The number of subjects in a problem-focused coping was 72(31.3%), the number of subjects in an emotion-focused coping was 158(68.7%) 3. There were statistically significant positive correlation between perceived stress and problem-focused coping method and the more emotion-focoused coping method.(r=.180, r= .209, P< .05). It means the more stress, the more problem-focused coping method and the more emotion-focused coping method. 4. There was significant difference the score of perceived stress according to sex (F=-5.057, P=.000)marital status, (F=-2.909, P=.004), economic level, (F=10.243, P=.000), paticipated meeting, (F=9.346, P=.000), perceived health status(F=5.117, P=.007). 5. There was significant difference the score of problem-focused coping method according to age(F=14.200, P=.000), marital status (F=2.432, P=.0160), economic level (F=14.410, P=.000), monthly income, (F=8.300. P=.000), income resource (F=10.235, P=.000), educational level (F=15.222, P=.000), occupation (F=1.544, P=.041), paticipated meeting (F=4.936, P=.008), perceived health status(F=5.655, P=.004). And there was significant difference the score of emotion-focused coping method according to monthly income(F=4.781, P=.009), income resource(F=2.930, P=.035), educational level(F=6.101, P=.003), religionF=2.698, P=.032), paticipated meetings(F=7.285, P=.001). As a result of the study, the elderly had a bit less stress and the two-thirds of the elderly used the emotion-focused coping. Thus, the more perceived stress, the more problem-focused coping method and the more emotion-focused coping method. Accordingly, to improve the quality of life of the elderly, there needs and applies a nursing intervention program that relieves the stress and use effective coping method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.481-482
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• 2007

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.4
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• pp.308-314
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• 2013

The vibration and stress analysis program of comprehensive vibration assessment program(CVAP) is to theoretically verify the structural integrity of reactor vessel internals(RVI) and to provide the basis for selecting the locations monitored in measurement and inspection programs. This paper covers the applicability of the vibration and stress analysis method of APR1400 RVI CVAP. The analysis method was developed to use 3-dimensional detail hydraulic and structural models with ANSYS and CFX. To assess the method, the hydraulic loads and structural reponses of OPR1000 were predicted and compared with the measured data in the OPR1000 RVI CVAP. The results predicted with this method were close to the measured values considerably. Therefore, the analysis method was developed properly.

• Structural Engineering and Mechanics
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• v.43 no.3
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• pp.321-336
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• 2012

As an improvement on the isoparametric element method, the derivation presented in this paper is close to that done by Wang (1990) for the 2-D finite element. We extend this idea to solve 3-D crack problems in this paper. A new displacement modelling is constructed with local solutions of three-dimensional cracks and a quasi-compatible isoparametric element for three-dimensional fracture mechanics analysis is presented. The stress intensity factors can be solved directly by means of the present method without any post-processing. A new method for calculating the stress intensity factors of three-dimensional cracks with complex geometries and loads is obtained. Numerical examples are given to demonstrate the validity of the present method. The accuracy of the results obtained by the proposed element is demonstrated by solving several crack problems. The results illustrate that this method not only saves much calculating time but also increases the accuracy of solutions. Because this quasi-compatible finite element of 3-D cracks contains any singularities and easily meets the requirement of compatibility, it can be easily implemented and incorporated into existing finite element codes.