• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.72-79
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• 1998

The goals of this research are to understand the regeneration characteristics in diesel particulate filter(DPF) using the cerium additive and throttling. The effects of throttling duration and spring tension of throttling valve were studied. Measurements were made on a 6 cylinder direct injection diesel engine and included pressure drop, filter inlet temperature, oxygen concentrations, and torque. The major conclusions of this work include; (i) the pressure drop is increased with increase of the engine load and the engine speed; (ii) the inlet temperature of the filter is reached $350^{\circ}C$ with certain engine operating condition which leads to sufficient temperature to regenerate with additive; and (iii) oxygen concentrations in the filter and engine torque during throttling operation are decreased by 2 percent and 36 percent, respectively, which are not critical about regeneration and vehicle operation.

• Proceedings of the Korean Society for Quality Management Conference
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• 2006.04a
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• pp.14-19
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• 2006

This study examined the effect of waiting in a service queue on the evaluation of service quality focused on its overall process, mediators and moderators The conceptual model of this paper integrates key variables derived from previous studies of consumer waiting behavior. Data obtained from actual customers in service queue at a hospital was used to test the theoretical framework. First, results from the path analysis confirm that negative affect and acceptability of the wait function as mediators in the process that the perceived duration of the wait affects customer's evaluation of overall service quality. Second, the analysis of the data, with the use of moderate regression shows that disconfirmation of wait time expectations, transaction importance, stability of wait time and wait environment work as moderate variables for the relationship between perceived duration of wait and negative affect. For the relationship between perceived wait time and acceptability of the wait, on the other hand, only transaction import ante shows a significant effect as a moderator.

• Journal of Welding and Joining
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• v.24 no.3
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• pp.34-41
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• 2006

The CD (Capacitor Discharge) stud welding utilizes the arc heat and pressure to attach the stud to the workpiece, which consists of the arc. ignition, arcing and pressure welding stages. In order to predict the dynamic behavior of the CD stud welding process, mechanical and electrical models are employed in this work. While the mechanical model estimates the duration of each stage, the electrical model predicts the voltage and current waveforms using the RLC circuit. Effects of process parameters such as the electric components and spring force are analyzed through simulation. It is found that the contact resistance and gap between the stud and base metal influence the tip fusing and arcing duration. The calculated results showed reasonably good agreements with the experiment results.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.5
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• pp.343-350
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• 2019

Map labels are the most recognizable map elements using the human visual system because they are essentially a natural language. In this study, an experiment was conducted using an eye-tracker to objectively record and analyze the response of subjects regarding visual attention to map labels. A primary building object was identified by analyzing visit counts, average visit duration, fixation counts, and the average fixation duration of a subject's gaze for an area of interest acquired using the eye-tracker. The unmarked rate of map labels in Google map, Naver map, and Daum map was calculated. As a result, this rate exceeded fifty-one percent, with the lowest rate recorded for Google map. It is expected that the results of this study will contribute to an increase in the diversity of research in terms of the spatial cognition approach for map labels, which is more helpful to users than the existing body of work on methods of expression for labels.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.3
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• pp.234-240
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• 2019

In this work, the magnetic arc reduction phenomena encountered in AC relay contacts were analyzed. To this end, arc duration, instantaneous voltage, and current changes due to changes in the magnetic field were observed. The arc generated at the contact point was affected by the magnitude of the applied magnetic field; the voltage and current waveforms rapidly intersected, resulting in a decrease in arc duration and arc energy. Furthermore, the orientation of the N pole of the magnetic field was found to play a role in the effectiveness of potential arc prevention.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.61-72
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• 2012

Background: The purpose of this study was to analyze the associations between physical therapists' work-related musculoskeletal pain, quality of life (QoL), and presenteeism. Methods: Self-reported questionnaires were given to 402 physical therapists in Korea. Variables examined included the prevalence of pain sites related to work, pain intensity, pain pattern, pain frequency, pain duration, pain rating score (PRS), general characteristics, QoL, and presenteeism. Results: Of the 314 physical therapists who responded, 251 (79.9%) reported work -related musculoskeletal pain in at least one body part. The most affected regions included the wrist and hand (21.0%), shoulder (19.6%), and lower back (19.1%). On average patients, QoL and presenteeism differed significantly between physical therapists who reported pain and those who did not (P < 0.05). QoL showed a negative correlation with the work-related musculoskeletal pain (P < 0.01) and presenteeism (P < 0.01), while the presenteeism and work-related musculoskeletal pain showed positive one(P < 0.01). Factors influencing a physical therapist's QoL included presenteeism, Working venues (Convalescent hospital), Work status (Contra ct worker) and professional experience, while the presenteeism included QoL, work status (Intern), PRS, working venues (Convalescent hospital), Area of specialty (Pediatrics), age, sex and working hour. Conclusions: Results show that physical therapists appear to be at a higher risk for work-related musculoskeletal pain. Therefore, administrators need to use the intervention strategies to manage the presenteeism and QoL of physical therapists.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.4
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• pp.331-345
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• 2018

Objective: Shift work including night work is known to be harmful to the health of nurses. This study was conducted in order to systematically review the academic literature on the health effects of working time patterns, including shift work or night work, among Korean nurses and propose a research direction for the future. Methods: We searched online academic databases to find relevant papers in domestic and international journals using the keyword terms 'shift work', 'night work', 'night shift', 'work shift', 'nurse', and 'Korea', and reviewed a total of 36 articles. Results: As a result of this literature review, more than half of the articles were found to investigate the health effects between shiftwork and non-shiftwork nurses. A few studies considered the shift type(n=6), frequency of night shift(n=4), and shiftwork duration(n=3) as working time patterns. These studies focused mainly on mental health(n=18) or sleep(n=15). Conclusions: Based on the review results obtained from this study, it is necessary to assess working time patterns of Korean nurses using a variety of variables including night-work-related factors, and various health outcomes should be examined considering the confounder.

• Women's Health Nursing
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• v.28 no.1
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• pp.18-26
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• 2022

Purpose: This study investigated whether parenting stress, work-family conflict, resilience affect retention intent in Korean nurses returning to work after parental leave. Methods: The participants in this study were 111 nurses recruited from 10 hospitals in Korea, who were working after formal parental leave from their hospitals. Collected data were analyzed using descriptive statistics, the t-test, analysis of variance, the Mann-Whitney U-test, Pearson correlation coefficients, and hierarchical regression. Results: Retention intention (33.80±7.78), parenting stress (101.70±17.57), and resilience (85.02±12.75) were at greater than moderate levels and a midpoint level of work-family conflict (29.63±7.00) was noted in this sample of mostly women nurses in their 30s. The factors affecting retention intent were parental leave duration, the number of times that participants had taken parental leave, health condition, work-family conflict, and resilience. The total explanatory power of these variables was 36.7%. Retention intent had a negative correlation with parenting stress and work-family conflict. Conversely, retention intent was positively correlated with resilience. Conclusion: This study supports the need for flexible adjustment of returning nurses' working hours and family-friendly policies to promote balance between work and family. It is also necessary to develop and apply measures that boost resilience and support health improvement for nurses returning to work.As nurses are often assigned to new areas of work upon return, training programs to aid their adjustment may also be helpful.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.5
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• pp.735-742
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• 2010

This paper reviewed the diving standards for underwater work in hostile environment and analyzed applied Navy diving technique, diving equipments and procedure for rescue operation of Navy ship Cheonan's missing crew occurred near Bak Ryung Do in March 2010. The operation was done beyond the international standards and safety practice, and by considering the nature of the mission, urgency and effectiveness as well as the detailed facts such as duration and depth of the dive, type of work to be performed, environmental conditions, time constraints of early rescue operation, it is analyzed that using air scuba diving system was adequate.

• Journal of Families and Better Life
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• v.11 no.1
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• pp.134-148
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• 1993

The study was designed to examine the present state of the provider-role consciousness of married working women in Korea and to identify five variable-clusters which were drawn from the theoretical perspectives. The subjects of this study were 573 married working women whose husbands also had their work. The statistical methods adopted for data analyses were frequencies. oneway ANOVA. Scheffe-test t-test, and multiple regression analysis. The major findings of this study can be summarized as follows; 1) The level of the provider-role consciousness of married working women was slightly high. 2) As for the aspects of the individual attribute variables. educational level job income age native area motive of work. and sex-role identity significantly influenced the provider-role consciousness of married working women. 3) Concerning the family background variables marriage duration number of children mother's experience of employment father's educational level and husbands's income were significantly related to the provider-role consciousness of married working women, 4) As for the social relationship variables. degree of participation in social associations significant others' attitudes toward housewife's work degree of domestic role sharing with husband and wife/husband income ration significantly affected the provider-role conscious-ness of married working women. Based on these findings it came to be revealed that multidirectional perspecitves were useful to identify variables which could predict the provider-role consciousness of married working women, Also it was revealed that the significant others' approvals for women's work were necessary to the establishment of the provider-role consciousness of married working women.