• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.595-602
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• 2016

An automotive wheel bearing is important part that translates rotating motion and bears vehicle weight. Recently, in accordance with the demands for $CO_2$ emission reduction and fuel economy regulation, the requirements for the weight reduction and miniaturization of vehicles has increased. Therefore, life evaluation technology of the bearings has increased in necessity. Since the bearing life is affected by many parameters such as bearing geometry, bearing specifications, and vehicle specifications, it is difficult to predict. In this paper, the bearing life was tested by varying the applied load and rotation speed and comparing them with the basic rating life and modified rating life that were suggested in ISO standards. From the results, it was found that there was a difference between the test life and theoretical life and modified rating life than basic rating life was to be relatively well predicted by test life.

• Research in Community and Public Health Nursing
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• v.29 no.2
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• pp.231-243
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• 2018

Purpose: This study tries to explore experiences with a special rating dementia service among family caregivers of elderly people with dementia. Methods: The participants were 11 family caregivers of elderly people with dementia and had used a day-care service from the special rating dementia service for more than 3 months. Data were collected through individual in-depth interviews and analyzed using content analysis. Results: Three categories emerged: "reminiscence of an entangled life", "feeling relieved from a stifled life", and "hope for a better life through help and support" with 8 sub-categories and 23 codes. By using the special rating dementia service, the participants experienced relief from the burden of caring for their elderly family member with dementia and restored their social relations or family relationships. They experienced a positive transition in which their caring for elderly family members with dementia was integrated into their daily lives, and they expressed their desires for better policies. Conclusion: These findings imply the importance and necessity of the special rating dementia service. Practical and systematic family support programs are necessary and proactive publicity activities by the government and public agencies are suggested to ensure that family caregivers can easily use the special rating dementia system.

• Transactions of Materials Processing
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• v.12 no.2
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• pp.88-93
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• 2003

Several alloy bearing steels have been starting to replace for conventional high carbon and high chromium bearing steel since 1980. In this paper the global bearing developing trends were summarized in several important aspects- developments in alloy bearing steels for improved service life, development of inclusion rating method in bearing steel and developments in bearing service life testing.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.1
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• pp.87-98
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• 2011

Objectives: To evaluate the clinical use of Kupperman's Index, Menopausespecific quality of life questionnaire(MENQOL), Menopause Rating Scale(MRS) by comparison with the Subjective measures of hot flush. Methods: The participants were 107 women (45-60 yr) who were not currently on hormone therapy, and had reached hot flash scores of 10 or higher. The evaluating indexes of this trial are hot flush score, hot flush VAS, Hot flush consistence time, sweating VAS, Kupperman`s Index, Menopause-specific quality of life questionnaire (MENQOL), Menopause Rating Scale(MRS). Results: 1. The hot flush score, hot flush VAS, sweating VAS were significantly correlated with each other, but the Hot flush consistence time with no special relationship was found on Subjective measures of hot flush 2. The Kupperman's Index, Menopause-specific quality of life questionnaire (MENQOL) and Menopause Rating Scale(MRS) were significantly correlated with each other. 3. There was significant correlation between Subjective measures of hot flush and Menopause-specific quality of life questionnaire(MENQOL), Thus Menopausespecific quality of life questionnaire(MENQOL) is considered the most suitable on hot flush related research. Conclusions: There was significant correlation between Subjective measures of hot flush and Menopausal scale, thus the use of various indicators are needed for the assessment of climacteric symptoms.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.819-825
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• 2021

In the industry, the use of lightweight bearings is increasing to minimize motor power loss, and in particular, the application of next-generation systems such as robots and drones is increasing. Bearing manufacturers are producing lightweight bearings by changing the bearing material, but related researches is insufficient. In this paper, life test and structural analysis were performed for lightweight bearings, and shape parameters and scale parameters were derived based on the life test results. It was confirmed that the shape parameter was 2.52 and the scale parameter was 164 hours. As a result of calculating the dynamic load rating based on the B₁₀ life, it was confirmed that the dynamic load rating of the lightweight bearing was 7% compared to the formula suggested by ISO 281. The reason is that the material of the retainer, which is a major failure part, is a polyamide 66 series that reacts sensitively to heat, so It is judged to show a lot of difference from the ISO 281 calculation formula.

• Journal of the Korean housing association
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• v.20 no.6
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• pp.57-65
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• 2009

In Korea, Housing Performance Rating Indication System was first adopted in 2006. Main purpose of the System is on developing criteria which can systematically measure the level of housing performance. Among the five categories of Housing Performance Rating Indication System, Repair Convenience is closely related to Remodeling which has been widely recognized as an alternative to the building reconstruction. Especially, as the actual housing supply level in Korea is reaching almost 100%, it is crucial to expand Long-life Housing through the effective maintenance and management. In addition, consumers should have an access to the performance ratings of apartment buildings on which they can rely on in choosing their own housings. And for construction companies, a performance code enacted by government will provide them with a standard that they can utilize in determining performance level of buildings that they build. This study examines data which has been obtained from the recent application of Housing Performance Rating Indication System and Repair Convenience category is main concern. Findings from the study will provide vital information in improving current Housing Performance Rating Indication System.

• Journal of the Korean housing association
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• v.20 no.6
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• pp.47-56
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• 2009

Housing Performance Rating Indication System was started in 2006. The aim of Housing Performance Rating Indication is to provide the guideline of housing performance. Repair Convenience is similar to Remodeling. Remodeling has been paid more attention as an alternative for reconstruction. Especially, now the actual house supply is facing almost 100%, it is time to keep and maintenance management of apartment buildings, and ultimately it will expand the Long life housing. Especially consumers has to have a right to select apartment buildings by comparing performance of house. For construction companies, they need a performance code that standardized by government, so they can provide a Certain performing house. This study examines data which has been obtained from the recent application of Housing Performance Rating Indication System and Repair Convenience category is main concern. Findings from the study will provide vital information in improving current Housing Performance Rating Indication System.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.1
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• pp.53-61
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• 2016

Angular misalignment has a significant effect on the characteristics of angular contact ball bearings (ACBBs). This paper presents an analysis of fatigue life for ACBBs subjected to angular misalignment. A simulation model is developed with de Mul's bearing model and the ISO basic reference rating life model. Simulation is performed to calculate the life of the ACBBs subjected to angular misalignment. The numerical results show that angular misalignment influences the load distribution significantly, thus reducing the bearing rating life. The fatigue life of ACBBs is decreased by angular misalignment regardless of axial preload, external radial load and rotational speed. The results show that angular misalignment should be maintained at less than 1mrad for ACBBs.

• Korean Journal of Biological Psychiatry
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• v.4 no.1
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• pp.116-120
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• 1997

This study investigated the antidepressant efficacy and it's impact on the quality of life of depressed patients. We performed Hamilton Depression Rating Scale(HDRS), and Montgomery-Asberg Depression Rating Scale(MADRS), and Health-related Quality of Life Questionnaire(HQLQ) to both tricyclic antidepressant(TCA) and sertraline groups. There were 16 subjects in this study. The tricyclic group had 9 subjects and the sertraline group had 7. The TCA and sertraline produced a similar degree of response. Both groups experienced a reduction of 70% or more in mean HDRS and MADRS total score after 6wks. In HQLQ, the TCAs group also showed improved bed disability days, alertness behavior, and social interaction, the sertraline group showed improved health perception, alertness behavior, home management, and social interaction. We suggested that the improvement of "Quality of life" were not in proportion to the clinical symptom's improvement. Therefore, clinicians should consider the benefit of antidepressant treatment in terms of quality of life.

• Journal of the Korean Society of Safety
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• v.18 no.1
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• pp.108-115
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• 2003

Bridges are rated at two levels by either Load Factor Design (LFD) or Allowable Stress Design (ASD). The lower level rating is called Inventory Rating and the upper level rating is called Operating Rating. To maintain bridges effectively, there is an urgent need to assess actual bridge loading carrying capacity and to predict their remaining life from a system reliability viewpoint. The lifetime functions are introduced and explained to predict the time-dependent failure probability. The bridge studied in this paper was built 30 years ago in rural area. For this bridge, the load test and rehabilitation were conducted. The time-dependent system failure probability is predicted with or without rehabilitation. As a case study, an optional rehabilitation is suggested, and fir this rehabilitation, load rating is computed and the time-dependent system failure probability is predicted. Based on rehabilitation costs and extended service lifes, the optimal rehabilitation is suggested.