• 한국기계가공학회지
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• 제14권2호
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• pp.112-120
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• 2015

In this study, the growth rate of surface cracks (da/dN) during the retardation period was analyzed in terms of effective stress intensity factor range(${\Delta}K_{eff}^*$) obtained by using the proposed effective plastic zone concept. Effective stress intensity factors obtained by using the effective plastic zone concept were smaller than those obtained by using Willenborg analysis. On the growth rate of surface cracks analyzed by ${\Delta}K$, the dependence of overload stress levels appears. On the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a linear relationship with two different slops between da/dN and ${\Delta}K_{eff}$. However, on the growth rate by ${\Delta}K_{eff}^*$ obtained by the proposed effective plastic zone concept, there is a linear relationship between da/dN and ${\Delta}K_{eff}^*$ that coincides with the results of constant amplitude loading.

• Safety and Health at Work
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• 제11권3호
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• pp.353-360
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• 2020

Background: Urban bus drivers work under conditions that are among the most demanding, stressful, and unhealthy with higher rates of mortality and morbidity as well as absenteeism and turnover. Methods: Drawing on the job demand-resource model, this study investigates the impacts of job characteristics on emotional exhaustion and the effects of emotional exhaustion on job outcomes (including job satisfaction, life satisfaction, organizational commitment, and turnover intention) in the context of bus drivers. Results: Using self-reported survey data collected from a sample of 320 Taiwanese urban bus drivers, results reveal that role overload and work-family conflict (as job demand factors) positively relate to emotional exhaustion, and organizational support (as a job resource factor) is negatively associated with emotional exhaustion. Emotional exhaustion has negative effects on both job satisfaction and organizational commitment. Job satisfaction positively leads to life satisfaction, whereas organizational commitment negatively relates to turnover intention. Conclusion: This study concludes that role overload and work-family conflict as two stressors related to job demands and organizational support as the job resource factor to affect emotional exhaustion which further influence well-being in bus driver context. The moderating effects of both extraversion and neuroticism on the relationship between job demands and emotional exhaustion are evident.

• 한국직업건강간호학회지
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• 제20권2호
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• pp.163-171
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• 2011

Purpose: This study is to investigate the job stress and presenteeism of nurses with work shift. Methods: The data were collected through questionnaires from 281 clinical nurses working for a university hospital located in D city from 13 to 28 of February, 2009. The data were analyzed by descriptive statistics, t-test, ANOVA, Scheffe verification test, Pearson correlation coefficient and multiple linear regression using SPSS/WIN 16.0. Results: The mean score of job stress was 3.47. Work overload and psychological burden scored the highest point as the sub-category of work stress factor. Work performance loss out of presenteeism showed 26.89 and perceived productivity, 79.79. Also 94.7% of respondents answered they had health problems. A significantly positive correlation was found among job stress, work performance loss and health issue. To determine the factors affecting presenteeism, work performance loss was associated with work overload and perceived productivity with interpersonal relationship conflict. Conclusion: Based on the findings of the study, job stress is positively correlated with work performance loss, and health problems. Therefore, health problems of nurses with work shift need to be considered and plans to manage their job stress affecting presenteeism need to be developed at an earlier stage.

• 대한치과의사협회지
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• 제53권6호
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• pp.418-426
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• 2015

The appropriate occlusion is one of the most important factors for the long-term success of implant and its restorations. The purpose of this review is to investigate and define occlusal considerations to reduce failure of implant prostheses. The physiological movement of implants is markedly lower than that of natural teeth and they also lack in occlusal sensitivity. Proper occlusal pattern may be assigned to compensate for the biological disadvantages and occlusal contacts must be formed where the cantilever effect is minimized. Moreover, the long-term success of implants after osseointegration can be assured by reducing early occlusal loading to avoid implant overloading and selecting appropriate occlusion material. Occlusal overload was brought by the number and location of occlusal contacts, which are under the clinician's control. The concept of implant occlusion is based on the concepts derived from traditional prosthetics. Moreover, there are few evidence on the concept or design of implant occlusion. Several occlusal design was recommended for implant prosthesis. Mutually protected occlusion, group function occlusion and bilateral balance occlusion was recommended for the specific types of implant restorations. This article reviews proper design of occlusion for implant restoration and offers occlusion strategy clinically.

• Animal cells and systems
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• 제8권2호
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• pp.97-103
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• 2004

The cytotoxic effect of iron was examined in peritoneal macrophage to determine contributing factors by iron injection to rat. Viability was reduced by 24% by the iron-overload and by 30% by short-term iron addition. Total iron was increased by 45% in the iron-overloaded with remarkable elevation (9 to 14 fold) in the presence of $FeSO_4$. Free calcium was also increased by 19% in control and 44% in iron-overloaded group due to additional $FeSO_4$ NO and MDA were increased by 40% and 136%, respectively, with significant reduction (37%) of NAD(P)H. RCR and cytochrome c oxidase activity were lowered approximately by 10% with reduction of mitochondrial membrane potential. Addition of iron was frequently associated with altered distribution of mitochondria of high membrane potential in the iron-overloaded macrophage. These results suggest altered mitochondria with high NO and low NAD(P)H due to iron.

• 유통과학연구
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• 제18권8호
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• pp.75-87
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• 2020

Purpose: This study uses the protection motivation theory and information processing theory to discuss the high number of fraud phenomenon in Indonesia which causes worries to the internet users. The second problem is the large amount of information transparency in e-commerce which actually hinders the users in making decisions so it causes a negative behavior pattern, namely discontinue usage intention. Design/methodology: Therefore, this research hopes to provide insight to the online or e-commerce business community, especially for Tokopedia, to develop its business from understanding the factors influencing consumer attitude when shopping online. The sample are students from Universitas Indonesia, Institut Teknologi Bandung, Institut Pertanian Bogor, Universitas Gadjah Mada and Institut Teknologi Surabaya, with total 900 respondents. Result: The results of this research indicate that ubiquitous connectivity (UC) variable significantly affects variables such as the privacy concern (PC), information transparency (IT) and information overload (IO). PC and IO variables also significantly affect Discontinue Usage Intention (DUI). Conclusion: This study gives a new perspective that despite the phenomenon, the millennial generation especially are not entirely concerned about the privacy concern, however, this study clearly shows that the privacy issue in the digital word continues to be something that needs to be cared for.

• 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.

• Human Ecology Research
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• 제59권3호
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• pp.297-310
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• 2021

This study examined the social wellbeing of working mothers of preschool children with the aim of identifying relationships between social wellbeing and influencing factors, focusing on the individual, relationship, and work environment of the mothers. Data on 390 working mothers were used for this study. The data were analyzed using the SPSS 18.0 program and descriptive statistics. Pearson's correlation analyses and hierarchical regression analyses were performed. The results show that social wellbeing has significantly positive correlations with education, monthly household income, number of children, age of the first child(8 and over), social capital for childcare, division of childcare, maternal role values, spouse's beliefs about paternal parenting involvement, and family-supportive work environment, as well as significantly negative correlations with weekly working hours, sociological ambivalence, spouse's beliefs about father's breadwinner role and gender-role values, job overload, and gender-role attitudes of coworkers. In addition, hierarchical regression revealed that spouse's beliefs about paternal parenting involvement and a family-supportive work environment were significantly positive predictors of working mothers'social wellbeing, whereas working mothers'sociological ambivalence toward their roles, job overload, and gender-role attitudes of coworkers were significantly negative predictors of working mothers'social wellbeing. These results point to ways of changing education and policy to improve the social wellbeing of working mothers.

• 한국IT서비스학회지
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• 제20권5호
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• pp.55-71
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• 2021

Technostress management is increasingly getting important as ICT advances and infiltrates every job and task. Especially with the advent of COVID-19, workers had to switch to teleworking utilizing ICT extensively. In this study, we developed a research model explaining antecedents and their impacts on technostress in telecommuting context, especially under the COVID-19 situation. The result revealed that techno-complexity, techno-invasion, and techno-overload are the dominant factors that affect the negative psychological responses in the COVID-19 situation. Among them, we found that techno-overload maintain the most significant influence. It is due to the lack of instant feedback on workload allocations in telework and the lack of adjustment period with the sudden shift to telecommuting. In the case of techno-complexity, employees seem to experience difficulty acquiring new technical skills. Finally, the techno-invasion came out significant, signifying the infiltration of working space by home-related activities. The emotion-focused coping strategy had a moderating effect. In contrast, the problem-focused coping strategy had no significant effect, indicating that an appropriate emotional coping strategy is more important for workers undergoing extreme changes in the work environment. Subsequently, practical and theoretical implications, limitations, and future research directions are discussed.

• 근관절건강학회지
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• 제3권2호
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• pp.151-165
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• 1996

The purpose of this study is to describe the acknowledgement of the cause of the illness in the patients with RA. I used naturalistic inquiry as a research methodology. The purposive sampling was conducted. 23 subjects who experienced RA, lived in middle-sized city in Korea, and 19 women and 4 men. I collected data using indepth structured interview, "What is the acknowledgement of the cause of the illness?" I used inductive data analysis-such as unitizing and categorizing. This process is used constant comparative method. Summerising the results of this study, the acknowledgement of the cause of the illness are composed of physical constitution, fatalism, the attribution of physical overload, the attribution of stress, the lack of nutrition. The factors which affect the acknowledgement of the cause of the illness are composed of internal factors, external factors, environmental factors. The internal factors are the weakness of the childhood, the illness experience in the family members, juvenile rheumatoid arthritis, personality, lack of nutrition. The external factors are pregnancy, delivery, role burden and conflict, economic problem. The environmental factors are humid condition, abrupt environmental change. It is needed to explaine the coping pattern according to the acknowledgement of the cause of the illness in the next research.