• 대한기계학회논문집A
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• 제31권10호
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• pp.1009-1016
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• 2007

Finite element alternating method has been suggested and used effectively to obtain the fracture parameters in assessing the integrity of cracked structures. The method obtains the solution from alternating independently between the FEM solution for an uncracked body and the crack solution in an infinite body. In the paper, the finite element alternating method is extended in order to obtain the elastic-plastic stress fields of a three dimensional inner crack. The three dimensional crack solutions for an infinite body were obtained using symmetric Galerkin boundary element method. As an example of a three dimensional inner crack, a penny-shaped crack in a finite body was analyzed and the obtained elastc-plastic stress fields were compared with the solution obtained from the finite element analysis with fine mesh. It is noted that in the region ahead of the crack front the stress values from FEAM are close to the values from FEM. But large discrepancy between two values is observed near the crack surfaces.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1063-1068
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• 2007

개인마다 소음, 음악과 음향진동 자극에 대한 인체의 반응은 상당한 차이가 발생하는 것을 고려하여 뇌파 파워의 상대적인 비율로 비교.고찰하였다. 우선 강한 소음 자극에 대한 뇌파의 변화는 긴장과 스트레스 증가를 의미하는 베타파의 증가 및 긴장완화와 안정을 의미하는 알파파의 감소를 보였고, 좋은 자극에 대해서는 그 반대의 효과를 보였다. 즉, 좋은 자극에 의한 스트레스저감의 효과가 있음을 확인하였다. 자극 후의 변화에서는 좋은 자극시와 마찬가지로 대체로 알파파가 증가하는 경향이 있지만 이와 반대의 경우도 발생하고있어 이 역시 개인차가 있음을 알았다.

• 한국콘텐츠학회논문지
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• 제8권11호
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• pp.242-250
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• 2008

아토피 피부염은 그 증상이 심각하고 그와 더불어 환자의 심리적 상태도 통제할 수 없을 정도로 황폐화되는 난치성 질환이다. 최근 연구보고들에 따르면 이 질환에 스트레스와 같은 심리적 요인이 중요하게 작용하며, 심리적 문제를 치료하는데 사용되는 기법들이 이 질환에도 유효하게 작용한다고 한다. 따라서 여기에서는 심리적 스트레스를 완화시켜 다양한 정신신체질환을 예방하고 치료하기 위한 목적으로 널리 사용되는 심신의학 프로그램을 아토피 질환의 추가적 치료 수단으로 제안하였다. 또한 심신의학 프로그램 의 치료 효과 모형과 치료자가 갖추어야 할 요건에 대해서도 논의하였다.

• 기본간호학회지
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• 제20권2호
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• pp.168-176
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• 2013

Purpose: The purpose of this study was to identify factors affecting quality of life according to Body Mass Index (BMI) of women college students. Methods: The research design was a descriptive survey design using a convenience sampling. Data were collected using self-report questionnaires. Participants were 348 women college students. Data analysis was done using SPSS/WIN 18.0 program for descriptive statistics, Pearson correlation coefficients and hierarchial multiple regression. Results: According to BMI, 3 groups of students were identified. Differences between the groups for quality of life were significant. The major factors affecting quality of life in the underweight group were departments (college), body stress and ego-resilience which explained 27.9% of the variance in quality of life. Body stress and ego-resilience were significant predictors explaining 23.1% of the variance in quality of life in the normal weight group. Ego-resilience was also a significant predictor in the overweight group explaining 15.2% of the variance in quality of life. Conclusion: Findings indicate a need to decrease body stress and strengthen ego-resilience to improve quality of life of women college students. Further studies are needed to examine nursing intervention strategies for improving quality of life for women college students.

• 지역사회간호학회지
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• 제24권3호
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• pp.314-322
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• 2013

Purpose: The purpose of the study was to examine associations between job stress and work-related musculoskeletal symptoms (WRMS) in street sanitation workers. Methods: A cross-sectional correlational study was conducted with 87 male street sanitation workers at E Gu in Seoul. The Job stress and WRMS were measured by using the Korean Occupational Stress Scale-Short Form and the KOSHA GUIDE H-9-2012 instrument, respectively. The WRMS was evaluated according to the National Institute of Occupational Safety and Health criteria. Results: The participants reported greater levels of insufficient job control and interpersonal conflict than the general Korean population. Of the participants, 44.8% reported WRMS at any body parts. Specifically, 28.7% reported WRMS at upper parts, while 16.5% reported WRMS at lower parts. Compared to low levels of job demand, its high levels were significantly associated with WRMS at both upper and lower parts of the body (OR=3.62, 95% CI=1.15~11.38; OR=3.60, 95% CI=1.04~12.39). Compared to low levels of occupational climate, its high levels were significantly associated with WRMS at upper parts of the body (OR=3.18, 95% CI=1.22~8.26). Conclusion: Among street sanitation workers, job stress may be a correlate of WRMS. Therefore, nursing strategies for reducing job stress are needed to prevent and manage WRMS.

• 대한기계학회논문집
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• 제14권1호
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• pp.119-129
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• 1990

본 연구에서는 선적분화 된 체적력항을 갖는 경계요소법을 이용하여, Griffi- th균열에 대한 열응력세기계수를 구하여 Sumi의 결과와 비교 검토하고, 유무한체내의 대칭 입술형및 대칭 익형 커스프균열들(symmetric lip and airfoil cusp cracks)의 열 응력세기계수를 균열묘면이 단열된 경우와 일정 온도로 유지된 경우에 대해 계산하고 자 한다.

• Journal of Nutrition and Health
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• 제23권7호
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• pp.504-512
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• 1990

In experiment 1, dietary self-selection of the 3 macronutrients, protein, fat, and carbohydrate were examined in male rats given 3 food cups of 80% carbohydrate, 80% protein, and 70% fat diets simultaneously. All the rats showed normal growth pattern and organ weight, which means they have ability to select just right kinds and amounts of nurients in order to support their growth and development. Mean values of caloric intake, body weight gain, serum lipid values and empty carcass compositions were not significantly differ between the upper and lower quartile groups of fat proportion of empty carcass compared to the lower quartile group(LF). Same feeding design was employed in experiment 2 where the effect of mild electric stress on food selection was studied. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The rats in both control and electric stress group revealed a normal growth curve and organ weights. The stress group showed higher caloric intake and body weight gain than control group, but no significant effects of stress on serum and empty carcass components was found. Even though normal rats seemed to select macronutrients according to their physiolosical needs, there were individual differences in food selection whether they were exposed to stress or not. Therefore life long individual food selection pattern may have a great influence on nutritional status and chronic degenerative diseases of eldery, and on aging process.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.561-568
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• 2014

Background: The skin is the largest body organ that regulates excretion of metabolic waste products, temperature, and plays an important role in body protection against environmental physical and chemical, as well as biological factors. These include agents that may act as oxidants or catalysts of reactions producing reactive oxygen species (ROS), reactive nitrogen species (RNS), and other oxidants in skin cells. An increased amount of the oxidants, exceeding the antioxidant defense system capacity is called oxidative stress, leading to chronic inflammation, which, in turn, can cause collagen fragmentation and disorganization of collagen fibers and skin cell functions, and thus contribute to skin diseases including cancer. Moreover, research suggests that oxidative stress participates in all stages of carcinogenesis. We report here a summary of the present state of knowledge on the role of oxidative stress in pathogenesis of dermatologic diseases, defensive systems against ROS/RNS, and discuss how physical activity may modulate skin diseases through effects on oxidative stress. The data show duality of physical activity actions: regular moderate activity protects against ROS/RNS damage, and endurance exercise with a lack of training mediates oxidative stress. These findings indicate that the redox balance should be considered in the development of new antioxidant strategies linked to the prevention and therapy of skin diseases.

• Journal of Mechanical Science and Technology
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• 제15권6호
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• pp.709-719
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• 2001

In particle or short-fiber reinforced composites, cracking of reinforcements is a significant damage mode because the cracked reinforcements lose carrying capacity. This paper deals with elastic stress distributions and load carrying capacity of intact and cracked ellipsoidal inhomogeneities. Three dimensional finite element analysis has been carried out on intact and cracked ellipsoidal inhomogeneities in an infinite body under uniaxial tension and pure shear. For the intact inhomogeneity, as well known as Eshelbys solution, the stress distribution is uniform in the inhomogeneity and nonuniform in the surrounding matrix. On the other hand, for the cracked inhomogeneity, the stress in the region near the crack surface is considerably released and the stress distribution becomes more complex. The average stress in the inhomogeneity represents its load carrying capacity, and the difference between the average stresses of the intact and cracked inhomogeneities indicates the loss of load carrying capacity due to cracking damage. The load carrying capacity of the cracked inhomogeneity is expressed in to cracking damage. The load carrying capacity of the cracked inhomogeneity is expressed in terms of the average stress of the intact inhomogeneity and some coefficients. It is found that a cracked inhomogeneity with high aspect ratio still maintains higher load carrying capacity.

• Safety and Health at Work
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• 제6권4호
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• pp.279-288
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• 2015

Background: In this study, the measurement of job stress of electric overhead traveling crane operators and quantification of the effects of operator and workplace characteristics on job stress were assessed. Methods: Job stress was measured on five subscales: employee empowerment, role overload, role ambiguity, rule violation, and job hazard. The characteristics of the operators that were studied were age, experience, body weight, and body height. The workplace characteristics considered were hours of exposure, cabin type, cabin feature, and crane height. The proposed methodology included administration of a questionnaire survey to 76 electric overhead traveling crane operators followed by analysis using analysis of variance and a classification and regression tree. Results: The key findings were: (1) the five subscales can be used to measure job stress; (2) employee empowerment was the most significant factor followed by the role overload; (3) workplace characteristics contributed more towards job stress than operator's characteristics; and (4) of the workplace characteristics, crane height was the major contributor. Conclusion: The issues related to crane height and cabin feature can be fixed by providing engineering or foolproof solutions than relying on interventions related to the demographic factors.