• JSTS:Journal of Semiconductor Technology and Science
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• 제15권1호
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• pp.1-6
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• 2015

In this work, the combined meandering-pattern stress-sensors were presented in order to achieve the high sensitivity of stress sensors. Compared to the previous works, which have been using the single meandering-pattern stress-sensors, the sensitivity was approximately observed to increase by 30%~70%. Also, in this paper, more simple and convenient stress-measurement method was presented.

• 스트레스연구
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• 제27권2호
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• pp.199-204
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• 2019

본 연구는 불안민감도가 과제수행과 스트레스 반응에 미치는 영향을 살펴보고, 이 과정에 우울감은 어떠한 영향을 미치는지 확인하였다. 참가자들은 제한된 시간에 암산 문제를 완수하였고, 불안민감도지수와 우울증 선별도구에 응답하였다. 더불어, 실험 전후 참가자들의 코르티졸(Cortisol) 변화량을 확인하였다. 그 결과, 불안민감도가 높은 사람은 과제수행의 정확도가 떨어지고 코르티졸 수치가 유의미하게 상승하였다. 또한, 불안민감도와 우울감이 모두 높은 참가자들이 코르티졸 수치가 가장 크게 상승하였다. 본 연구는 자기보고식 응답에 근거하여 임상증상을 기술하는 것을 넘어 과제수행의 정확도와 생화학적 지표를 함께 제시함으로써, 보다 안정적으로 개인의 불안민감도와 우울감의 관계를 논의하였다는 의의를 지닌다.

• Child Health Nursing Research
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• 제11권4호
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• pp.415-426
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• 2005

Purpose: The purpose of this study was to identify relations among the parenting stress, maternal sensitivity to infant cues, parenting environment of first-time mothers. Method: The participants were 194 first-time mothers of babies aged 1-6 months who visited well-baby clinics in 5 hospitals. The data were collected from April 15 to June 15, 2003. Results: The parenting stress level was moderate with a mean score of 2.4(range 1-5). The parent domain and parent-child relationship domain of the parenting stress scale were significantly correlated with maternal sensitivity to infant feeding cues (r=-.178, p<.05; r=-.197, p<.01). Parenting stress was significantly correlated with childrearing environment(r=-2.19, p<.01). Parenting stress and childrearing environment were significantly different according to the educational level of the mothers and their prenatal care. Conclusions: Nursing interventions to reduce parenting stress in first-time mothers are needed to improve maternal sensitivity to infant cues and childrearing environment which foster infant development.

• 한국간호교육학회지
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• 제26권2호
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• pp.157-166
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• 2020

Purpose: This study was conducted to explore how clinical practice stress and moral sensitivity affect the clinical competency of nursing students. Methods: Participants had completed at least a one year (2 semesters) clinical nursing practicum through K University in D Metropolitan City. A total of 188 nursing students were recruited: third grade (n=104) and fourth grade (n=84). The questionnaires were adopted with clinical practice stress, Korean version of moral sensitivity questionnaire (K-MSQ), and the clinical competency. Results: Clinical competency was positively correlated with patient-oriented care (r=.27, p<.001) and the professional responsibility (r=.32, p<.001) of the moral sensitivity (r=.27, p<.001). The attitude of medical personnel experiencing clinical practice stress shows a significant positive relationship with clinical competency (r=.15, p=.038). The attitude of medical personnel (β=.09, p=.194) experiencing clinical practice stress, patient-oriented care (β=.16, p=.041) and professional responsibility (β=.23, p=.003) of the moral sensitivity explained 12% of the variance in clinical competency (F=9.17, p<.001). Therefore, the influential factors on clinical competency were two sub-factors of moral sensitivity. Conclusion: Moral educational programs should be considered to develop a nursing students' clinical competency.

• 한국전산구조공학회논문집
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• 제35권6호
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• pp.367-374
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• 2022

본 논문에서는 역전파 방법 기반 자동미분법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 응력제한조건이 있는 위상최적화문제는 특이점(singularity)과 응력의 국부성(local nature of stress constraint)문제, 그리고 설계 변수에 대한 비선형성의 문제를 포함하고 최적해를 얻기가 매우 힘들다. 특이점 문제를 해결하기 위해서 응력 완화(stress relaxation) 기법을 사용하였고, 응력의 국부성을 해결하기 위해 p-norm을 이용한 전역 응력치를 제한조건에 사용하였다. 설계 변수에 대한 비선 형성을 극복하기 위해 해석적인 방법으로 정확한 설계민감도를 구하는 것이 중요하다. 위상최적설계에서 기존에는 보조변수방법 (adjoint variable method)을 사용하여 빠르고 정확한 설계민감도를 구했지만, 설계민감도를 해석적으로 구해야 하고, 보조평형방정식을 추가로 풀어야 하는 어려움이 있다. 이를 해결하기 위해서 인공신경망에서 최적 가중치(weights)와 편차(biases)를 구할 때 쓰이는 역전파 기법을 이용하여 설계민감도를 구하고 이를 응력제한조건을 고려한 위상최적설계에 적용하였다. 역전파 기법은 자동미분에 쓰이는 기법으로 목적함수나 제한조건에 대한 설계민감도를 별도의 수식유도 없이 간단하게 구할 수 있는 장점이 있다. 또한, 미분값을 구하는 역전파의 과정이 보조평형방정식을 푸는 것보다 계산시간이 빠르고 해석적 방법으로 구한 설계민감도와 같은 정확도를 보여준다.

• 대한기계학회논문집A
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• 제28권6호
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• pp.670-676
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• 2004

Most metallic materials and alloys show rate independence or negative rate sensitivity in some temperature region when dynamic strain aging occurs. It is generally recognized that negative rate sensitivity is an essential feature of dynamic strain aging that can depend on strain and/or strain rate. The unified viscoplasticity theory based on overstress is applied to reproduce a change of rate sensitivity type that depends on strain or strain rate. This is accomplished through the introduction of a single new term in the growth law of the equilibrium stress, which is a tensor valued state variable of the model. It is also shown that the new term can be used to reproduce a dramatic increase of rate sensitivity in dynamic plasticity.

• 대한기계학회논문집A
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• 제32권9호
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• pp.770-781
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• 2008

In nuclear power plants, ferritic low alloy steel components were connected with austenitic stainless steel piping system through alloy 82/182 butt weld. There have been incidents recently where cracking has been observed in the dissimilar metal weld. Alloy 82/182 is susceptible to primary water stress corrosion cracking. Weld-induced residual stress is main factor for crack growth. Therefore exact estimation of residual stress is important for reliable operating. This paper presents residual stress computation performed by 6" safety & relief nozzle. Based on 2 dimensional and 3 dimensional finite element analyses, effect of welding variables on residual stress variation is estimated for sensitivity analysis.

• 소성∙가공
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• 제13권7호
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• pp.600-607
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• 2004

This paper addresses a viscoplastic constitutive model that allows a consistent way of modeling positive and negative rate sensitivities of flow stress concerned with dynamic strain aging. Based on the concept of continuum mechanics, a phenomenological constitutive model includes the use of a yield surface within the framework of unified viscoplasticity theory. To model negative rate sensitivity, rate-dependent back stress is introduced and flow stress in fully developed inelastic deformation regime is thus decomposed into the plastic contribution of rate independency and the viscous one of rate dependency.

• 대한기계학회논문집A
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• 제26권10호
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• pp.1953-1960
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• 2002

The viscoplasticity theory based on overstress, one of the unified state variable theories, is generalized to model zero (no influence of loading rate) and negative (flow stress decreases with loading rate) as well as positive (flow stress increases with loading rate) rate sensitivity in a consistent way. On the basis of the long-time asymptotic solution the different types of rate sensitivity are classified with respect to an augmentation function that is introduced in the evolution law fur a state variable equilibrium stress. The theory predicts normal relaxation and creep behaviors even if unusual rate sensitivity is modeled. The constitutive model fir the behavior of a modified 9Cr-1 Mo steel at various temperatures is then compared with experimental data found in the literature.

• 대한감각통합치료학회지
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• 제2권1호
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• pp.33-42
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• 2004

Objective : To evaluate the sensory processing ability in relation to parenting stress and find the sensory modulation areas affecting the parenting stress in disabled children Methods : Parents of 124 children with disabilities between 3 to 7 years receiving occupational therapy in Seoul and Gyeonggi-do made out the questionnaire and in items of questionnaire, Short Sensory Profile and Parenting Stress Index of short form was included. Results : Among general information, parenting stress of parents had significant correlation with the degree of disability and correlation with the lower level 2 of Parenting Stress Index. The more sensory processing disability was increased, the more parenting stress was increased. Parenting stress showed the significant correlation with movement sensitivity area and under-responsiveness/behaivor area seeking specific stimulation among sensory processing areas and had significant correlation with tactile sensitivity and auditory filtering. Sensory processing areas which affect the most the Parenting Stress were movement sensitivity and under-responsiveness/behaivor area seeking the specific behavior among sensory control disabilities. Conclusion : The parenting stress of parents with the disabled children had the correlation with sensory processing ability. The difficulty of sensory processing increased the parenting stress. Hence, in order to improve children's sensory processing ability, the appropriately coping program should be developed and the appropriate intervention for improvement of sensory processing ability of children will be necessary.