• 대한정형도수물리치료학회지
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• 제24권2호
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• pp.43-49
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• 2018

Background: In this study, the importance of constipation and back pain was assessed by regression analysis of the effects of stress, dietary habits, and water intake on constipation in women in their twenties and the influence of constipation and body mass index (BMI) To provide basic data. Methods: This study selected 109 having constipation of 120 students attending G University in Gwangju and eating habits, water intake level, stress and BMI. Trigger point at the tip of erector spina was palated with tenderness set in order to examine whether muscle tenderness and actual low back muscle tenderness level were same and left and right parts were measured three times and average of Max values was used. We examined the effect of constipation on low back pain and examined constipation and BMI to determine whether they affected low back pain. Results: There was no significant difference in eating habit although there was a significant difference in the effect of stress and water intake on constipation. Constipation had significant difference in back pain. However, there was no significant difference in BMI, normal weight, overweight, and obesity except for low body weight. Conclusions: This study found that constipation was associated with stress levels, water intake, and back pain. In conclusion, this study suggests basic data to prevent and treat constipation-related back pain, and recommends plenty of water intake, proper exercise and stress management to prevent constipation.

• Nuclear Engineering and Technology
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• 제52권8호
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• pp.1862-1870
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• 2020

The purpose of this study is to investigate the effect of welding residual stress on operating stress in designing a nuclear turbine welded rotor. A two-dimensional axisymmetric finite element model is employed to calculate the residual stress before and after post weld heat treatment (PWHT), and then the superposition of residual stress after PWHT and operating stress at normal speed and overspeed were discussed. The investigated results show that operating stress can be affected significantly by welding residual stress, and the distribution trend of superposition stress at the weld area is mainly determined by welding residual stress. The superposition of residual stress and operating stress is linear superposition, and the hoop stress distribution of superposition stress is similar with the distribution of residual stress. With the increasing overspeed, the distribution pattern of the hoop superimposed stress remains almost unchanged, while the stress level increases.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 추계학술대회
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• pp.483-493
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• 2009

The global economic recession caused a great change of the labor environment such as restructurings and unstable employment. This facts brought about an increase in sense of rivalry, over workload, job uncertainty and lowering of self-confidence. Due to the fact that the work process and employing system in construction field is little differ from normal industries, especially, labors working in construction field are much exposed to the job stress. On this study, we survey construction-field labors and made an analysis of the gathered data through the statistic method to reveal what kind of job-stress factors influence on the defects of construction works. As the result, we investigated the truth of the induction factors which cause the job-stress in costruction field and proposed an alternative plan for an effective job-stress management which make the defect rate low.

• 방사성폐기물학회지
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• 제22권2호
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• pp.201-210
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• 2024

Because most spent nuclear fuel storage casks have been designed for low burnup fuel, a safety-significant high burnup dry storage cask must be developed for nuclear facilities in Korea to store the increasing high burnup and damaged fuels. More than 20% of fuels generated by PWRs comprise high burnup fuels. This study conducted a structural safety evaluation of the preliminary designs for a high burnup storage cask with 21 spent nuclear fuels and evaluated feasible loading conditions under normal, off-normal, and accident conditions. Two types of metal and concrete storage casks were used in the evaluation. Structural integrity was assessed by comparing load combinations and stress intensity limits under each condition. Evaluation results showed that the storage cask had secured structural integrity as it satisfied the stress intensity limit under normal, off-normal, and accident conditions. These results can be used as baseline data for the detailed design of high burnup storage casks.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.499-502
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• 2006

This paper presents computed results of FEM analysis on the tribological contact behaviors of a primary sealing components of mechanical face seals for a small hydro-power turbine. The FEM computed results present that the contact area between seal rings and seal seats is very important for a good tribological performance such as low friction heating, low wear, high contact normal stress in a primary seal ing components. Based on the FEM computation, model III in which has a small sealing contact area shows low dilatation of primary sealing components, and high contact stress between a seal ring and a 1)seal seat.

• 한국임상수의학회지
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• 제22권2호
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• pp.136-140
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• 2005

This experiment is designed to determine the relationship between groomers' activities and stress. The experimenter worked with 2 female dogs and 3 male dogs owned by clients. They were 22 months old on an average and weighed 5.5kg on an average. The concentration of cortisol in blood was measured with radioimmunoassy(RIA). The concentration of cortisol in blood was high in the morning and evening and was low in the afternoon. In a normal condition, the concentration of cortisol in blood was $1.4{\mu}g/dL$, which increased to $4.98{\mu}g/dL$ after 1 hr of grooming, and then returned to normal at the termination of grooming. The survey shows that grooming acted as a stressor, which seems to have an influence on the health of dogs. So it is absolutely necessary that systematic and constant research should be conducted to reduce stress at the time of grooming.

• International Journal of Reliability and Applications
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• 제15권2호
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• pp.125-150
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• 2014

Accelerated life tests (ALTs) are extensively used to determine the reliability of a product in a short period of time. Test units are subject to elevated stresses which yield quick failures. ALT can be carried out using constant-stress, step-stress, progressive-stress, cyclic-stress or random-stress loading and their various combinations. An ALT with linearly increasing stress is ramp-stress test. Much of the previous work on planning ALTs has focused on constant-stress, step-stress, ramp-stress schemes and their various combinations where the stress is generally increased. This paper presents an optimal design of ramp soak-stress ALT model which is based on the principle of Thermal cycling. Thermal cycling involves applying high and low temperatures repeatedly over time. The optimal plan consists in finding out relevant experimental variables, namely, stress rates and stress rate change points, by minimizing variance of reliability function with pre-specified mission time under normal operating conditions. The Burr type XII life distribution and time-censored data have been used for the purpose. Burr type XII life distribution has been found appropriate for accelerated life testing experiments. The method developed has been explained using a numerical example and sensitivity analysis carried out.

• 대한불안의학회지
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• 제10권2호
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• pp.170-175
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• 2014

Objective : The aims of this study was to evaluate relationship between body dissatisfaction, personality characteristic, and stress in young adults. Methods : One hundred and ninety five young, healthy, and normal participants filled out all 3 types of self-reported questionnaire, the Body Dysmorphic Disorder Examination-Self Report (Korean version of BDDE-SR ; K-BDDE-SR), Neuroticism, Extraversion, Openness-Five Factor Inventory (NEO-FFI) and Stress Scale of Korean version of the Depression Anxiety Stress Scale (K-DASS-21). Results : Out of the 195 participants, 30% (n=59) was male and 70% (n=136) was female. There was no statistical difference between high K-BDDE-SR group (K-BDDE-SR score 75 percentile or higher, n=50) and low K-BDDE-SR group (K-BDDE-SR score below than 75 percentile, n=145) in terms of weight, height, and BMI. In high K-BDDE-SR group, neuroticism was significantly higher than low K-BDDE-SR group, and extraversion, agreeableness, conscientiousness were significantly lower than low K-BDDE-SR group. Also, level of stress in high K-BDDE-SR group was significantly higher than low K-BDDE-SR group. Conclusion : Our study revealed that individual's with more body dissatisfaction were more neurotic and stressful. Thus, body dissatisfaction and diverse psychiatric diseases should be considered in treating neurotic and stressful young adults.

• Journal of Animal Science and Technology
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• 제65권4호
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• pp.878-889
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• 2023

Animal welfare during transport became an largely issue because of increasing demand for improved animal welfare standards. Most studies on the animal welfare during transportation have concentrated on the atmosphere and the temperature of the truck compartments. Thus, the objective of study was to collect and quantify three axis acceleration and determine the effect of bedding for transporting pigs from farm to slaughterhouse. A total of 2,840 crossbred fattening pigs with a live weight of approximately 115 kg were used. They were raised in the same commercial farms and transported to the same commercial slaughterhouse. A 3×2×2 completely randomized factorial design was used to investigate effects of rubber type bedding (bedding or non-bedding) and two levels of driving style (aggressive or normal) in three different time periods with different outside temperatures. Air temperature treatments were as follow: high temperature ([HT] higher than 24℃); low temperature ([LT] lower than 10℃); normal temperature ([NT] 10℃ to 24℃). In our experiment, pigs transported under aggressive driving style showed lower (p < 0.05) pH and water holding capacity (WHC) than those transported under normal driving style. Pigs transported under normal driving style showed a lower percentage of drip loss (DL) (p < 0.05) than those transported with an aggressive driving style. Also, transported with bedding showed higher (p < 0.05) lying behavior but lower (p < 0.05) sitting behavior than those transported without bedding. Pigs transported under normal driving style showed lower (p < 0.05) cortisol level than those transported under aggressive driving style. In conclusion, aggressive driving style cause acute stress in pigs, while bedding helps alleviate acute stress in pigs during transportation in LT.

• 대한기계학회논문집
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• 제12권4호
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• pp.790-805
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• 1988

본 연구에서는 유리섬유 강화 에폭시 복합재료의 파괴 강도와 피로 수명을 정 규분포, 로그 정규 분포와 2모수 및 3모수 Weibull 분포 함수의 기대값으로 살펴 보았 다. 2연속 응력 피로 실험 [작은 응력에서 큰 응력으로의 실험(low-high test), 큰 응력에서 작은 응력으로의 실험(high-low test)]의 결과도 분포 함수들을 사용하여 분 석하였다. 비통계학적 누적 손상 법칙들(non-statistical cumulative damage rules) 을 2연속 응력 피로 수명 분산 예측에 이용하기 위해서 동등 순위 가정(equal rank assumption)을 확장하여 수정하였다. 수정한 누적 손상 모형은 Miner의 법칙, Brou- tman과 Sahu의 손상모형 및 Hashin과 Rotem의 모형 등이다.