• Proceedings of the KSME Conference
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• 2000.04a
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• pp.212-217
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• 2000

The reliable determination of the stress intensity factors for cracks in bolted Joints is needed to evaluate the safety and fatigue life of them widely used in mechanical components. The weight function method is an efficient technique to calculate the stress intensity factors for various loading conditions using the stresses of an uncracked model. In this paper the mixed-mode stress intensity factors for cracks in bolted joints are obtained by weight function method, in which the coefficients of weight function are determined by finite element analyses far reference loadings. The effects of the magnitude of clearance and factional coefficient on the stress intensity factors are investigated.

• Journal of Korean Biological Nursing Science
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• v.12 no.3
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• pp.140-147
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• 2010

Purpose: The purpose of this study was to identify the effects of the cognitive training program on cognitive function, stress and depression in geriatric hospitals. Methods: The subjects of the experimental group were 17 elderly patients who attended the cognitive training program in Geriatric Hospitals and the subjects of the control group were 15 elderly patients who attended in geriatric hospitals. The persons in training group must take cognitive training program for 4 weeks by 3 times a week. The Mini-mental State Examination Korea version (MMSE-K), Geriatric depression Scaleshort form-Korea version (GDS-K) and Korean Computerized Neurobehavioral Test (KCNT) were utilized to determine cognitive function, stress and depression. The collected data were analyzed by descriptive statistics, t-test and ANOVA using SPSS/PC 12.0 program. Results: Cognitive function (t=-7.625, p=.000) in the elderly after receiving the cognitive training program was significantly more improved than before intervention. Also, Stress and depression (t=2.73, p=.004) was significantly more reduced than before the intervention. Conclusion: This cognitive training program was partially effective in improving cognitive function, neurobehavioral performance and reduce stress and depression. Therefore, it is recommended that this program be used in clinical practice as an effective nursing intervention in geriatric hospitals.

• Korean Journal of Human Ecology
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• v.16 no.2
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• pp.251-257
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• 2007

The combined impact of maternal depression, parenting stress, infant cry, and infant temperament on family functions was examined. The sample included 257 mothers in the near communities. Questionnaires completed by the mothers who had 0-36 month old children were used to measure depressive symptoms in mothers, infant cry, infant temperament, parenting stress, and family function. Maternal depression, parenting stress, infant crying and infant temperament had negative influence on family adaptability and family cohesion. Mother's depression had negative effect particularly on infant cry. Infant cry had positive effect on infant temperament. Infant temperament had high direct effect on parenting stress. As a result, it had negative influence on family function.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1659-1664
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• 2003

A cracked plate with a patch bonded on one side was treated with a crack-bridging model using weight function: assuming continuous distribution of springs acting between th crack surfaces, the stress intensity factor of the patched crack was numerically obtained. Especially in the case of a patched crack subjected to residual non-uniform stress, the stress intensity factor was easily with the corresponding approximate weight function. This paper presented the stress intensity factors for a crack partially patched within a finite plate or a patched crack initiated from a notch.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.73-78
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• 2004

In this research, the photoelastic experimental hybrid method with Hook-Jeeves numerical method has been developed: This method is more precise and stable than the photoelastic experimental hybrid method with Newton-Rapson numerical method with Gaussian elimination method. Using the photoelastic experimental hybrid method with Hook-Jeeves numerical method, we can separate stress components from isochromatics only and stress intensity factors and stress concentration factors can be determined. The photoelastic experimental hybrid method with Hook-Jeeves had better be used in the full field experiment than the photoelastic experimental hybrid method with Newton-Rapson with Gaussian elimination method.

• Molecules and Cells
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• v.46 no.12
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• pp.727-735
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• 2023

Stem cells require high amounts of energy to replicate their genome and organelles and differentiate into numerous cell types. Therefore, metabolic stress has a major impact on stem cell fate determination, including self-renewal, quiescence, and differentiation. Lysosomes are catabolic organelles that influence stem cell function and fate by regulating the degradation of intracellular components and maintaining cellular homeostasis in response to metabolic stress. Lysosomal functions altered by metabolic stress are tightly regulated by the transcription factor EB (TFEB) and TFE3, critical regulators of lysosomal gene expression. Therefore, understanding the regulatory mechanism of TFEB-mediated lysosomal function may provide some insight into stem cell fate determination under metabolic stress. In this review, we summarize the molecular mechanism of TFEB/TFE3 in modulating stem cell lysosomal function and then elucidate the role of TFEB/TFE3-mediated transcriptional activity in the determination of stem cell fate under metabolic stress.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.10
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• pp.1659-1670
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• 2001

It has been reported that cracks at mechanical fastener holes usually nucleate as elliptical corner cracks at the faying surface of the mechanical joints and grow as elliptical arc through cracks after penetrating the opposite surface. The weight function method is an efficient technique to calculate the stress intensity factors fur elliptical cracks using uncracked stress field. In this study the weight function method for three dimensional mixed-mode problem applied to elliptical comer cracks Is modified for elliptical arc through cracks and the stress intensity factors at two surface points of elliptical arc through cracks at mechanical fastener holes are analyzed by the weight function method. This study consists of two parts and in part I , the weight function method for elliptical arc through cracks is developed and verified.

• CELLMED
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• v.14 no.4
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• pp.73.1-73.4
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• 2024

Objective: Case study on improving body homeostasis by ortho-cellular nutrition therapy. Methods: A 48-year-old Korean man underwent OCNT due to symptoms of insomnia and decreased physical function due to extreme chronic stress. Results: After exposure to OCNT, fatigue, sleep quality, and brain fog symptoms improved, and overall physical performance improved, including liver function recovery. Conclusion: For people who suffer from symptoms of decreased physical function in various aspects due to extreme stress, applying OCNT can help alleviate symptoms.

• Journal of Welding and Joining
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• v.35 no.1
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• pp.55-60
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• 2017

There are many Industry Code and Standard (ICS) for Structural Integrity Assessment (SIA) on welded structure with defect. The general ICSs, such as R6, BS 7910 and API 579-1/ASME FFS-1, provide equations to determine the upper bound residual stress profiles based on collections from many literatures. However, these residual stress profiles used in the SIA cause the conservative design for welded structures. In this study, the structural integrity assessment for girth weld in pipeline has been conducted based on fracture mechanics. In addition, thermo-elastic plastic FE analysis was performed for evaluating the residual stress of girth weld in pipeline. The weight function solution is used to determine the stress intensity factor using the residual stress profile obtained by the FE analysis. This approach can account for redistribution and relaxation of residual stress as the defects grow. In order to the evaluate quantitative comparison between BS 7910 and weight function solution, structural integrity assessment determining allowable crack size on cracked pipe was performed with failure assessment diagram.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.2
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• pp.258-267
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• 1998

This study reviews the influence function method(IFM) for calculating stress intensity factors (SIFs, K) and modifies it to apply for the estimating the residual fatigue life for the cracked components under complex stress fields. An IFM has been developed to analyze SIFs for surface cracks which are subjectedto nonuniformly distributed stresses. Through elastic superposition, the influence function method properly accounts for redistribution of stress as the crack grows through the component. This influence function is unique to the given geometry and independent of the loading. Some examples have been provided to show the effectiveness of the IFM including the distributions of K in a residual stress field. The significant effect of residual stress upon fatigue crack growth in a welded component has been demonstrated with the IFM.