• 제목/요약/키워드: stress factors

검색결과 6,272건 처리시간 0.033초

유한요소 해석에 의한 맞대기 용접 이음의 응력집중에 과한 연구 (Finite Element Analysis of the Stress Concentrations for Butt Welded Joints)

  • 구병춘;최병일;김재훈
    • Journal of Welding and Joining
    • /
    • 제22권4호
    • /
    • pp.59-64
    • /
    • 2004
  • The purpose of this study is to investigate the influence of weld bead profiles on stress concentration factors of double V groove butt-welded joints. The influence of three parameters such as toe radii, flank angles and bead heights on the stress concentration factors is studied by finite element analysis. It is shown that the three parameters have similar effects on the stress concentration factors. Finally a formula to estimate the stress concentration factors considering the three parameters and others is proposed and estimated results are compared with the results obtained by finite element analysis.

Development of Stress-tolerant Crop Plants

  • Park, Hyung-In;Kang, Jung-Youn;Sohn, Hee-Kyung;Kim, Soo-Young
    • Journal of Plant Biotechnology
    • /
    • 제4권2호
    • /
    • pp.53-58
    • /
    • 2002
  • Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these "environmental or abiotic stresses", which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity, In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.n factors.

Influence of Rehabilitation Therapists Six Personality Factors on Job Stress and Turnover Intention

  • Wang, Joong San;Park, Hyun Ju
    • 국제물리치료학회지
    • /
    • 제9권3호
    • /
    • pp.1528-1532
    • /
    • 2018
  • This study aimed to analyze the six personality factors of rehabilitation therapists and to identify the effects of these factors on their job stress and turnover intention. This study involved physical therapists and occupational therapists as rehabilitation therapists. A structured questionnaire was distributed to rehabilitation therapists, and 186 answered copies were used for data analysis. The results of the survey were as follows: Among the six personality factors, the rehabilitation therapists showed the highest level of honesty-humility and the lowest level of openness to experience. In terms of job stress, the subjects experienced the highest level of stress from job autonomy and the lowest level of stress from relationship conflict. In terms of turnover intention and work motivation reduction, the subjects scored above the median points, showing their high levels of turnover intention. In addition, higher levels of extraversion and agreeableness in the rehabilitation therapists led to a statistically significant reduction in their turnover intention and a statistically significant decrease in most of their job stress factors. Based on these results, organizational management aimed at increasing the personality factors of extraversion and agreeableness is necessary as a measure to effectively manage rehabilitation therapists' job stress and turnover intention.

예능 PD, 예능 작가의 직무스트레스요인이 스트레스 수준 및 우울에 미치는 영향 (The Effects of Entertainment Producer and Writer Job Stress Factors on Stress Level and Depression)

  • 류시내;구정완
    • 한국산업보건학회지
    • /
    • 제29권1호
    • /
    • pp.108-118
    • /
    • 2019
  • Objective: The purpose of this study was to investigate the effects of occupational stress factors on the level of stress and depression of entertainment program producers and entertainment program writers. Methods: This study was based on analysis of a survey collected by 65 respondents out of 224 questionnaires who are entertainment program PDs and entertainment program writers. The survey was conducted from December 20, 2017 to February 20, 2018. Results: In the logistic regression analysis conducted to investigate the factors affecting the stress level in the job-related characteristics of a) higher total career, b) shorter working period in the current firm, c) longer weekly working hours and d) more count of weekend work, the results found higher stress levels. In the sub-factors of job stress, the stress level encountered by respondents was significantly higher for those with a) higher job demand, b) lower insufficient job control and c) higher job instability. In the logistic regression analysis conducted to investigate the factors affecting depression, the depression level in entertainment PD was higher than the entertainment writer in the sociodemographic characteristics. In the sub-factors of job stress, the stress level was significantly higher for those with higher job demand, lower insufficient job control, and higher job instability. For job-related characteristics, depression was significantly higher for longer weekly working hours. Conclusions: Entertainment program producers and entertainment program writers suffer from psychosocial stress and depression which are caused by excessive job demands, lack of job autonomy and job instabilities. Those factors must be managed and also their workweek should be shortened.

중등 보건교사의 직무 스트레스에 영향을 미치는 요인 (Factors Affecting Job Stress of School Nurse in Secondary School)

  • 강인순;조수연;정희진
    • 한국학교보건학회지
    • /
    • 제23권2호
    • /
    • pp.286-295
    • /
    • 2010
  • Purpose: This study was conducted to identify the factors affecting the job stress of school nurses and reducing their the job stress by analyzing degree of the stress according to the factors related to job stress. Methods: The participants were 136 school nurses who worked in Pusan province. The Data were collected by self-reporting questionnaires from Dec. 11th in 2006 to Feb. 9th in 2007. The data were analyzed by Frequency, Mean, t-test, ANOVA, Pearson Correlation Coefficient and Stepwise multiple regression analysis (SPSSwin 12.0s). Results: There was significant difference of the degree of job stress in age. There was significantly negative relationship between the job characteristics and job stress (r=-.473), job satisfaction and job stress (r=-.561), personal values and job stress (r=-.429), achievement motivation and job stress (r=-.215) at p<.01 level. The major factor which influence the degree of job stress was job satisfaction. Conclusion: The factors affecting the job stress of school nurses was correlated with one another and influenced to the degree of the job stress directly and indirectly. The factor that affected the degree of the job stress directly was the job satisfaction and the personal values. As shown this result, it is important that the factor of the job stress lies in the mental characteristics.

전업주부 스트레스에 따른 가공편의식품 구매태도 및 선택속성의 구조적 관계 - 서울, 경기지역 주부를 대상으로 - (Structural Relations of Convenience-Processed Food Purchasing Attitude and Selection Attribute according to Housewives' Stress - Focus on Housewives in Seoul and Gyeonggi Areas -)

  • 김난희;박영일;주나미
    • 대한영양사협회학술지
    • /
    • 제25권4호
    • /
    • pp.257-268
    • /
    • 2019
  • This study provides basic data on how stress impacts the processed convenience foods purchase attitudes and the selection attributes of housewives. The stress consists of 3 factors, which were housework stress, family relation stress and economic stress. The processed convenience food purchase attitude consisted of 2 factors, which were peripheral influence purchase and conviction purchase. The processed convenience food selection attribute consisted of 4 factors, which were quality, convenience, packaging and price. Factor loading confirmation and reliability test were conducted, and the reliability was confirmed with Cronbach's alpha coefficients for all the factors exceeding 0.5. The high stress levels showed significantly high stress factors of housework, family relations and economic stress (P<0.001). The high stress group was shown to make purchases by recognizing peripheral influences (P<0.01). When the selection properties of processed convenience foods depending on different stress levels were examined, it was revealed that among the three groups, the low stress group least considered the price aspect (P<0.01). After deducting the factors, AMOS (Analysis of Moment Structure) was used to conduct the confirmatory factor analysis for verifying validity. The structural equation model was used to determine the path coefficient. From the processed convenience foods purchase attitude, the peripheral influence purchase had significantly positive (+) effects on convenience (P<0.05). Also, conviction purchase was shown to have significantly positive (+) effects on quality (P<0.05). Housework and family relation stress were shown to have negative (-) effects on processed convenience foods selection attribute, and economic stress was shown to have positive (+) effects, although no significant relationships were revealed.

중.고등학교 운동선수가 인지하는 스트레스, 우울, 사회적 지지가 학교생활적응에 미치는 영향 (Effect of stress, depression, and social support on school life adjustment of athletes in the middle and high school students)

  • 문재우
    • 한국학교ㆍ지역보건교육학회지
    • /
    • 제12권2호
    • /
    • pp.43-67
    • /
    • 2011
  • Objectives: The purpose of this study was to analyze factors affecting school life adjustment of athletes in middle and high school. Methods: The data in this study came from the survey which conducted to 500 students of physical education high school athletes and elite athletes in general school from the beginning of December 2009 to the end of January 2010 in Seoul and Kyunggi. Finally 436 cases was used. The dependant variable in this study was school life adjustment. And the independent variables were socio-demographic factors, stress and depression factors, social support factors. The analysis methods were T-test, ANOVA, correlation analysis, stepwise multiple regression analysis by using SPSS Ver. 12.0. Results: First, there was a statistically significant result between school life adaptation and sex, family circumstances, life satisfaction variables Second, there was a negative correlation between social support and stress, depression. Third, there was a negative correlation between school life adjustment and some stress factors, all depression factors. Also relationship between school life adjustment and social support showed a positive correlation. Fourth, Taking a look at the impact on school life adjustment, family factors and practical environmental factors in the stress factors and the feeling of worthlessness in the depression factors appeared to influence negatively. Also teachers' support in the social support factors showed positive effects. Explanatory power of the final regression model was 25.6%. Conclusions: The first step in order to improve the school life adjustment of athletes in middle and high school is the teachers' support. Athletes in middle and high school can have capability, responsibility, initiatives through teachers' attention and affection. The effective prevention education and health education programs on stress and depression should be introduced and carried out in the health education programs actively for student athletes to be free from stress, depression.

  • PDF

U-노치 및 균열을 갖는 보의 응력집중계수 및 응력확대계수 (Stress Concentration Factor and Stress Intensity Factor with U-notch and Crack in the Beam)

  • 서보성;이광호
    • 대한기계학회논문집A
    • /
    • 제40권5호
    • /
    • pp.513-523
    • /
    • 2016
  • 단순보와 외팔보의 U-노치 및 균열에 대한 응력집중계수 및 응력확대계수를 유한요소법 및 광탄성실험에 의해 해석하였다. 해석결과를 사용하여 응력집중계수 및 응력확대계수의 추정 그래프를 얻었다. 노치의 응력집중계수해석을 위하여 무차원 노치 길이 H(시편의 높이)/h=1.1~2, 무차원 틈 간격 r(노치선단의 반경)/h=0.1~0.5로 하였다. 여기서 h=H-c, c=노치길이이다. 해석결과 틈 길이가 증가할수록 그리고 틈 간격이 좁아질수록 응력집중계수는 증가 한다. 응력집중계수는 단순보가 외팔보다 더 크게 나타나나, 실제 일정한 하중과 노치길이 및 틈 간격 하에서 최대 응력값은 단순보보다 외팔보에서 크게 발생함을 알 수 있었다. 균열해석을 위하여 무차원 균열길이 a(균열길이)/H=0.2~0.5로 하였다. 균열의 길이가 증가 할수록 무차원 응력확대계수는 증가한다. 일정한 하중과 일정한 균열길이하에 응력확대계수값은 단순보 보다 외팔보에서 크게 발생함을 알 수 있었다.

한국 근로자의 업무관련성 스트레스와 위험요인 (Work-related Stress and Risk Factors among Korean Employees)

  • 최은숙;하영미
    • 대한간호학회지
    • /
    • 제39권4호
    • /
    • pp.549-561
    • /
    • 2009
  • Purpose: Work-related stress and risk factors among Korean employees were identified in this study. Methods: Data were obtained from employees aged 20 to 64 using the Korean Working Conditions Survey 2006 (KWCS). Multiple logistic regression analysis using SAS version 9.1 was performed to examine risk factors of work-related stress by gender. Results: The age-adjusted prevalence of work-related stress among male and female employees was 18.4% and 15.1% respectively. After adjustments for multiple variables among both male and female employees, there was a significant relationship between work-related stress and risk factors including education, company size, work time, ergonomic risks, biological chemical risks, and job demands. The significant variables for male employees were housework load, occupational class, and shift work, and for female employees, type of employment. Conclusion: There is a need to develop and support intensive stress management programs nationally giving consideration to work-related stress associated with working time, physical working environment, and job demands. Based on gender specific approaches, for male employes, stress management programs should be developed with consideration being given to occupational class and shift work. For stress management programs for female employees, consideration needs to be given to permanent employment status, specifically those in small companies.

일부 알코올 의존자의 삶의 질 및 재발 스트레스 요인과의 관련성 연구 (A Study on Relation between the Quality of Life and Factors for recurrent Stress of Alcohol Dependents)

  • 유호달;정명수
    • 대한의료기공학회지
    • /
    • 제13권1호
    • /
    • pp.105-144
    • /
    • 2013
  • This study intended to provide fundamental data to take countermeasures against recurrent stress by analyzing the health-related quality of life and factors for recurrent stress of alcohol dependents. Structured questionnaire was prepared for patients who quitted drinking after they had been hospitalized for alcohol dependence to take medical treatment but suffered recurrence, and analysis on health-related quality of life and environmental factors with drinking risk was conducted. The quality of life was at a relatively satisfactory level, where pain was found at the highest level and general health condition was found at the lowest level. Environmental factors with drinking risk were found to be a moderate level, drinking for the reason of family and friends in terms of complications with other persons was found to be highest, and then job, self control, bad emotions, and social pressure on drinking were found in order. For health-related quality of life, the quality of life was found to be high in case of the only son, professional job, well-educated persons, and no history of hospitalization. Regarding factors for recurrent stress, stress was found to be high in case of the eldest son and being without religion, and the lower was the quality of life, the higher were recurrent stress and environmental factors with drinking risk. It was found that demographic factors including age, marriage, and job influenced the recurrence of alcohol dependence, and factors for recurrent stress, etc. also influenced recurrent alcohol dependence with drinking risks. Specially, the lower was the quality of life, the higher were factors for recurrent stress, and drinking risks, therefore measures to improve the quality of life are required to be taken to prevent alcohol dependence from recurrence.