• Tribology and Lubricants
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• v.28 no.2
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• pp.70-80
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• 2012

Non-contact type mechanical face seals installed in mechanical systems prevent leakage of working fluid using thin working fluid film between stator and rotor. For that purpose, various kinds of surface profiles, grooves and conings have been applied on seal surfaces of stator and rotor to generate hydrodynamic and hydrostatic pressure. The thickness distribution of working fluid film is one of important factors which affect the working performances of mechanical face seal, and it is strongly affected by the surface height profiles of stator and rotor. Therefore, appropriate design of surface height profiles of stator and rotor is necessary to optimize the working performances and life of mechanical face seal. In this study, numerical analysis using finite volume method was conducted to estimate the working performances of wavy mechanical face seals which have 36 coning combinations. As results, minimum thickness of working fluid film, leakage volume of working fluid and friction torque in static equilibrium condition of mechanical face seal, and stiffness of working fluid film were obtained. The results show that the working performances of mechanical face seal were affected by the coning combinations which can change the thickness distribution of working fluid film and pressure distribution in sealing region of mechanical face seal.

• Journal of Korean Academy of Nursing
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• v.29 no.4
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• pp.802-816
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• 1999

The purposes of this research were to identify nursing interventions performed by Korean nurses and to compare the interventions performed by nurses working in the oriental medicine hospitals and with those performed by nurses working in the general hospitals. The samples consisted of 144 Korean nurses working in three hospitals, 70 nurses working in the oriental medicine hospitals and 74 nurses working in the general hospitals. The Nursing Interventions Classification (NIC) Use Questionnaire developed by the Iowa Intervention Project team was translated to Korean and verified using the method of back-translation. The questionnaire consists of 433 intervention labels and definition. Thirteen interventions were used at least daily by nurses working in the oriental medicine hospitals, while twenty-one interventions were used at least daily by nurses working in the general hospitals. The most frequently used interventions by nurses working in the oriental medicine hospitals were Documentation, Shift Report Vital Signs Monitoring, Pressure Ulcer Prevention, Positioning, Fall Prevention, Exercise Promotion, Intravenous (IV) Therapy, Pressure Ulcer care, and Bed Rest Care in that crder. For nurses working in the general hospitals the most frequent intervention was Analgesic Administration, followed by the interventions of Medication Administration : Parenteral and Intravenous Therapy (IV) Therapy, Documentation, Intravenous(IV) Insertion, Shift Report, Fall Prevention, Vital Signs Monitoring, Medication Adnninistraction : and, Fluid Monitoring, and Medication Maragement in that order. The interventions performed least often by nurses working in the oriental medicine hospitals were Hemodialysis Therapy and Bleeding Reduction : Antepartum Uterus, while the interventions performed least often by nurses working in the general hospitals were Rape Trauma Treatment and Contact Lens Care. The nurses working in the oriental medicine hospitals performed the interventions in the Physiological : Complex domain significantly more often than the nurses working in the general hospitals, while the nurses working in the general hospitals performed the intervention in the Behavior domain significantly more often than the nurses working in the oriental medicine hospitals. This study suggests that further study will be needed to developed and validate more interventions sensitive to Korean culture.

• Korean Journal of Labor Studies
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• v.19 no.1
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• pp.35-64
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• 2013

This paper explores whether or not a minimum wage increase can do much to alleviate working poor. For this purpose, I analyze transitions from working poor to working non-poor and to unemployment or non-economically active states, using KLIPS (Korea Labor and Income Panel Study). This study uses the multilevel multinomial logit model to control unobserved individual heterogenous characteristics. It finds that a minimum wage increase tends to cause a higher probability of transitions from working poor to working non-poor. It is also discovered that a minimum wage increase is not negatively related with the persistence of the working state. It is concluded that minimum wage increases are likely to be effective in improving the living standards of the 'working poor'.

• Safety and Health at Work
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• v.15 no.1
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• pp.102-109
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• 2024

Background: In today's modern world, longer working hours, shift work, and working at night have become major causes of the disruption of our natural circadian rhythms. This study aimed to investigate the effects of the type of shift work (rotating vs. fixed day), duty period (on-duty vs. off-duty), and working period within each shift (nighttime vs. daytime) on the circadian rhythm characteristics of nurses who provide direct patient care. Methods: This cross-sectional study used a purposive sampling method. Cosinor analysis was applied to analyze the actigraphy data of nurses providing direct patient care for seven consecutive days. The linear mixed effects model was then used to determine any variances between shift type, duty period, and working period within each shift for the nurses. Results: The mesor value did not differ according to nurses' shift type, duty period, and working period within each shift. The amplitude was statistically higher in on-duty nurses and in daytime working hours. The acrophase was significantly delayed in nighttime working hours. As well as nurses in rotating shift had experience. Conclusion: Our findings revealed that the peak activity of nurses occurs significantly later at night while working and nurses working during nighttime hours may have a weaker or less distinct circadian rhythm. Thus, this study suggests that limits be placed on the number of rotating nighttime shifts for nurses.

• Journal of Families and Better Life
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• v.4 no.1
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• pp.71-93
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• 1986

The purpose of this study is to identify sevral variables which were assumed to have relationships with the role conflict and marital satisfaction of married working women, and to examine the relationship of the role conflict and marital satisfaction of married working women in Korea. The data for this study was obtained from the survey of the 262 married working women who reside in the city of Seoul employing questionnaire method. Such methods as frequency, percentile, factor analysis, analysis of variance (t-test, F-test), and Pearson's correlation were used for the statistical analysis for this study. The major findings of this study can be summarized as follows; 1) The role conflict level of married working women was related to variables such as age, the number of children, work time, husband's support, job satisfaction, motivation to work outside the home. 2) The overall marital satisfaction was relatively high when they have two children and the presence of household work help. Futhermore, ut was found that marital satisfaction considerably high when husband's support and job satisfaction was highly accorded. 3) The role conflict and marital satisfaction of married working women were significantly negatively correlated.

• Journal of Families and Better Life
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• v.27 no.4
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• pp.117-126
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• 2009

The purpose of this study was to analyze the difference of working mothers' work-child rearing strain and their demand on special care services according to each mother's work conditions and childcare situation. 477 working mothers who have only one child each were gathered by the use of the purposive quota sampling method and analyzed with t-test, F-test, correlation, and multiple regression. The main results showed that working mothers had high work-child rearing strain and demand on special care services when their working conditions were inflexible and they were not satisfied with the care services for their child. The major variable which explained working mothers' demand on special care services was e their work-child rearing strain.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.8
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• pp.934-940
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• 2006

The aims of this study is to develop working robot for a installed trolley cable of an electric train and objective of this paper is to implement mobile control of working robot. In this paper an approach to method for scheme of a mobile control system is presented in a dynamic hybrid velocity/tension control of working robot. The working robot is composed the velocity and tension controllers using the concept of two-degrees-of-freedom servo-controller. This robot moved at same time a certain distance to constrain a constant tension and installed a trolley cable of an electric train. To move the robot the velocity control system have design and implemented. Simulation and experimental results are presented to illustrate the validity of designed mobil scheme.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.224-228
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• 2000

The piercing and blanking of thin sheet metal working is specified division in press die design and making. In order to prevent the detects, the optimum design of the production part, strip process layout, die design, die making and try out etc. re necessary the analysis of effective factors. For example, theory and practice of metal shearing process and its phenomena, die structure, machine tool working for die making, die materials and its heat treatment, metal working in industrial and its know how etc. In this study, we analyzed whole of data base, theoretical back ground of metal working process, and then performed the progressive die tryout with the screw press. This study regards to the aim of small quantity of production part's press working. Part 1 of this study reveals with production part and strip process layout design.

• Journal of the Korea Safety Management & Science
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• v.7 no.2
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• pp.85-94
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• 2005

The purpose of this study is to execute the investigation of injurious factors causing muscle-skeletal diseases at an automotive glass manufacturing company and, on the basis of the results, to enhance productivity by the improvement of working environment. By using an survey and an ergonomic evaluation method, symptoms of muscle-skeletal diseases of workers and working postures at each process were analyzed, and quantitative evaluation of muscle-skeletal disease risk against each process was performed. Based on the result of the evaluation, to enhance the working environment, improvement of worktable, working space, tools, and outfit was suggested, and induction of mechanical system was also suggested. Suggested improvement plan was applied to the workplace step by step and it is confirmed that improvement plan not only removes the injurious factors of muscle-skeletal diseases but also is effective to enhance productivity.

• Geomechanics and Engineering
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• v.24 no.3
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• pp.227-235
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• 2021

A criterion and a method for solving a problem on the prevention of mine working fracture under the action of tectonic and gravitational forces are offered. Based on minimal criterion, theoretical analysis of the definition of the optimal shape of working in the rock mass weakened by arbitrarily located rectilinear cracks was carried out. A closed system of algebraic equations allowing to minimize the stress state and stress intensity factors depending on mechanical and geometrical characteristics of the rock, is constructed. The relation between the shape of the working and the stress intensity factors and also location and sizes of the cracks is obtained. The found optimal shape of working increases load-bearing capacity of the rock.