• Journal of Advanced Marine Engineering and Technology
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• 제14권1호
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• pp.72-82
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• 1990

It is impossible to directly analyse stress distribution on thin bevel Gear. On this Paper, the author propose a method to analyse the stress of thin bevel gear boundary element method and develope a computer program. The propriety of this program is verified by comparing the numerical calculating results with theoretical results.

• Journal of the Korean Society of School Health
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• 제16권1호
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• pp.55-66
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• 2003

This study was conducted to evaluate the differences of perceived stress level and stress coping behavior for 360 elementary school children in rural area and 360 in urban area. The questionnaire survey was done from December 10 to December 20, 2001. The results were as follows: 1. There was no significant difference of perceived stress level between rural and urban areas, but there were significant difference of stress coping behavior between them. 2. Significant difference of perceived stress level and stress coping behavior among groups of grade was found. 3. There was significant difference of perceived stress level and stress coping behavior between male and female. 4. There was significant difference of stress coping behavior according to perceived stress levels In conclusion, perceived stress level and stress coping behavior in elementary school children were different according to their grade and sex. It is important to teach them proper stress coping method, depending on their grade and sex. But, we have to focus on the development and application of stress self-control program, which enables children to cope with stress for themselves. Based on: 1. Before starting the study, the subjects should be examined about whether they have ever been on stress education program before or not. 2. The educational environments and the development and implementation of teaching program for the proper stress coping method are needed. 3. This study was performed through the questionnaire for perceived stress level and stress coping behavior, but various methods like observation, person-to-person interview should be used for the further in-depth study.

• Korean Journal of Animal Reproduction
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• 제21권4호
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• pp.325-333
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• 1997

Recent evidence indicates that growth factors modulate response of mammary epithelial cells to environmental stress. The objective of this study was to examine the cellular and biochemical responses of mammary tissue to environmental stress caused by artificial mastitis. For experimental a, pp.oach, toxins of most mastitis causing organisms(Staph. aureus or Strep. agalactiae) and heat stress(42$^{\circ}C$) were artificially exposed to mammary tissue. Effects of these environmental stresses on cell growth, cell death and heat shock protein synthesis were examined. Lactating mammary tissure were cultured under basal medium(DMEM) su, pp.emented with insulin(10$\mu\textrm{g}$/ml) and aldosterone(1$\mu\textrm{g}$/ml). All treatment groups in heat stress at 42$^{\circ}C$ incubation significantly decreased DNA synthesis rates in comparison with those at 39$^{\circ}C$(P<0.05), however, these decreased DNAa synthesis rates were recovered by addition of adenosine(10$\mu$M) and IGFI(10ng/ml). Similar results were obtained when tissue growth rates were measured by DNA content/tissue. Strep. agalactiae toxin did not significantly decreased DNA content/tissue in comparison with no treatment of bacterial toxin with or without heat stress, however, tended to decrease DNA contents/tissue without heat stress. In the fluorography analysis, heat stress(42$^{\circ}C$ incubation) slightly increased 35S-methoionine labelled 70kd protein synthesis. These results indicate that environmental stress caused by artificial mastitis slightly decreased mammary growth or mammary size, however, these results could be recovered by addition of adenosine and IGF-I.

• Korean Journal of Health Education and Promotion
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• 제33권1호
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• pp.13-22
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• 2016

Objectives: By using six years of KNHANES dataset (2008~2013) about 60 ages older people, we analyzed how the depression prevalence rate in the elderly is influenced by disease and activity limit. Especially, to add a sense of more reality, we adopted stress experience as a control variable to see how the depression prevalence rate in the elderly is influenced by disease and activity limit depending on the stress experience. Methods : We adopted six years of KNHANES dataset, indicating that our results were based on long period of time capable of considering temporal patterns in the depression prevalence rate in the elderly. Total 1,160 elderly people in KNHANES were selected for our empirical analyses. Dependent variable is either 0 or 1 depending on whether the elderly people feel depression. Main explanatory variables for our study include disease and activity limit. Logistic regression analysis was applied for two group such as stress experience and non-experience. Results : According to the empirical results, stress factor is found to be significant in explaining the depression in the elderly. Depression prevalence rate increased when the elderly has stress experience: chronical disease(OR=1.650), chronical disease with activity limit(OR=3.388), non-chronical disease with stress(OR=11.841) chronical disease with stress (OR=13.561) and chronical disease with activity limit and stress(OR=28.691). Conclusions: The finding suggest that the Countermeasures of elderly's depression alleviation should include stress management.

• Journal of The Korean Society of Integrative Medicine
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• 제8권3호
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• pp.163-172
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• 2020

Purpose : The purpose of this study was to investigate economic anxiety, self-efficacy, and financial stress levels in middle-aged male and identify factors affecting financial stress and provide baseline data for the development of nursing interventions to reduce financial stress in middle-aged male. Methods : Participants were 91 middle-aged male who live in Seoul and Gyeonggi Province. The data collection period was from April 1, 2020, to May 1. In this study, the questionnaire of economic anxiety, self-efficiency, financial stress was used. The data were analyzed by average, standard deviation, minimum, maximum correlation and regression using SPSS version 21.0. Results : In this study, the financial stress of middle-aged male affected economic anxiety with significant results (β=.628, p<.001). The absolute model's explanatory power was 36.8 % (adjusted R2=.368), indicating that economic anxiety affects financial stress levels in middle-aged male (F=27.151, p<.001). Conclusion : This study shows that economic anxiety affects financial stress. Based on the research results, basic data for the development and application of nursing programs to reduce financial stress were presented in consideration of the economic anxiety of middle-aged males. Therefore, there is a need for mediation to help middle-aged men positively recognize real-life situations and changes in society. Such mediation involves the development and application of educational and counseling programs that can reduce financial stress and economic anxiety in middle-aged men.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.52-59
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• 2006

Purpose: The purpose of this study was to evaluate the influence of apical-coronal implant position on the stress distribution after occlusal and oblique loading. Materials and Methods: The cortical and cancellous bone was assumed to be isotropic, homogeneous, and linearly elastic. The implant was apposed to cortical bone in the crestal region and to cancellous bone for the remainder of the implant-bone interface. The cancellous core was surrounded by 2-mm-thick cortical bone. An axial load of 200 N was assumed and a 200-N oblique load was applied at a buccal inclination of 30 degrees to the center of the pontic and buccal cusps. The 3-D geometry modeled in Iron CAD was interfaced with ANSYS. Results: When only the stress in the bone was compared, the minimal principal stress at load Points A and B, with a axial load applied at 90 degrees or an oblique load applied at 30 degrees, for model 5. The von Mises stress in the screw of model 5 was minimal at Points A and B, for 90- and 30-degree loads. When the von Mises stress of the abutment screw was compared at Points A and B, and a 30-degree oblique load, the maximum principal stress was seen with model 2, while the minimum principal stress was with model 5. In the case of implant, the model that received maximum von Mises stress was model 1 with the load Point A and Point B, axial load applied in 90-degree, and oblique load applied in 30-degree. Discussion and Conclusions: These results suggests that implantation should be done at the supracrestal level only when necessary, since it results in higher stress than when implantation is done at or below the alveolar bone level. Within the limited this study, we recommend the use of supracrestal apical-coronal positioning in the case of clinical indications.

• Journal of the Ergonomics Society of Korea
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• 제26권3호
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• pp.35-43
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• 2007

This study aims at providing some basic material to be made use of for establishing plans through which one can reduce job-related stress, through conducting a survey on the sources of stress and then distinguishing its symptoms by the sources. As the methods of the study, we conducted a questionnaire survey of some selected medium enterprises' employees in the National Capital region and analysed the results. The questionnaire was designed by using the dynamic stress model of Cooper and Eaker and consisted of 85 questions to examine the sources of stress, the characteristics of personalities, and symptoms by each type of stress. The total valid respondents were 392 persons indicating 65.3% of the response rate. For analysing the results, a rating scale was used, and the reliability and validity were tested by using Cronbach's alpha coefficient. As the result of the study, those workers in medium enterprises were found to be put under much stress by responsibility, physical environment factors and career development factors and so on. As physical symptoms of job-related stress, eye fatigue, stiffness in their shoulders, headache, worry or anxiety, and waist ache presented most in the respondents. In addition, as behavioral symptoms, chronic fatigue was most indicated. In organizational symptoms, dissatisfaction about the company and lack of self-motivation for the job performance were found to show most. Moreover, the results indicated that the closer personalities to those appearing in persons mostly of type A they had, the more they were put under intensive stress by the vagueness of their roles and responsibility among all the job characteristics.

• Journal of the Korea Concrete Institute
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• 제23권3호
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• pp.365-376
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• 2011

The current Concrete Structural Design Code (2007) prescribe the equivalent rectangular stress block of the ACI 318 Building Code as concrete compressive stress distribution for design of concrete structures. The rectangular stress block may be enough for flexural strength calculation, but realistic stress-strain relationship is required for performance verification at selected limit state in performance-based design. Moreover, the ACI rectangular stress block provides non-conservative flexural strength for high strength concrete columns. Therefore a new stress distribution model is required for development of performance-based design code. This paper proposes a concrete compressive stress-strain distribution model for design and performance verification. The proposed model has a parabolic-rectangular shape, which is adopted by Eurocode 2 and Japanese Code (JSCE). It was developed by investigation of experimental test results conducted by the authors and other researchers. The test results cover high strength concrete as well as normal strength concrete. The stress distribution parameters of the proposed models are compared to those of the ACI 318 Building Code, Eurocode 2, Japanese Code (JSCE) and Canadian Code (CSA) as well as the test results.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제22권4호
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• pp.236-245
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• 2011

Objectives : The objective of this study was to evaluate the relationship of the parenting stress with their children's characteristics for typically developing preschool children. Methods : Parents of 38 preschool children (mean age : 4.4${\pm}$0.7 years, 22 boys) completed the Korean Parenting Stress Index, the Korean Child Behavior Checklist, the Conners Parent and Teacher Rating Scale-Abbreviated form (CPRS and CTRS), the Junior Temperament and Character Inventory, the Children's Sleep Habit Questionnaire and the Social Responsiveness Scale. All 38 children performed the Comprehensive Attention Test (CAT). Results : The children's inattentive and hyperactive problems, as measured by the CBCL, CPRS and CAT, had positive correlation with parenting stress. Both internalizing and externalizing behavioral problems were associated with parenting stress. Of the child's temperament dimensions, Novelty Seeking and Harm Avoidance were positively correlated with parenting stress, but Persistence and Cooperativeness were negatively correlated with parenting stress. Sleep anxiety and other sleep characteristics showed a correlation with parenting stress. Social Motivation and Communication were also positively related to parenting stress. Conclusion : Our results suggest that parenting stress could be related to the children's cognition, emotion, behavioral characteristics, sleep habits and social development. These results could assist in the development of interventions to improve the parental well-being in typically developing preschool children.

• Journal of Nutrition and Health
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• 제52권2호
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• pp.176-184
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• 2019

Purpose: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. Methods: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as $IRE1{\alpha}$, $eIF2{\alpha}$ and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with $750{\mu}M$ palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. Results: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of $p-IRE1{\alpha}$, $p-eIF2{\alpha}$ and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. Conclusion: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.