• Journal of the Korean Society for Precision Engineering
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• v.20 no.5
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• pp.140-147
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• 2003

As the huge energy transfer systems like as nuclear power plant and steam power plant are operated for a long time at a high temperature, mechanical properties are changed and ductile-brittle transition temperature is raised by degradation. So it is required to estimate degradation in order to assess the safety, remaining life and further operation parameters. The sub-sized specimen test method using surveillance specimen was developed for evaluating the integrity of metallic components. In this study, we would like to present the evaluation technique of the ductile-brittle transition temperature by the sub-sized specimen test. The four classes of the thermally aged 1Cr-1Mo-0.25V specimens were prepared using an artificially accelerated aging method. The tensile test and fracture toughness test were performed. The results of the fracture toughness tests using the sub-sized specimens were compared with the evaluation technique of the ductile-brittle transition temperature.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.579-584
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• 2001

As the huge energy transfer systems like as nuclear power plant and steam power plant are operated for a long time, mechanical properties are changed and ductile-brittle transition temperature is raised by degradation. So it is required to estimate degradation in order to assess the safety, remaining life, and further operation parameters. The sub-sized specimen test method using surveillance specimen was developed for evaluating the integrity of metallic components. In this study, we would like to present the evaluation technique of the ductile-brittle transition temperature by the sub-sired specimen test. The four classes of the thermally aged 1Cr-1Mo-0.25V specimens were prepared using an artificially accelerated aging method. The tensile test and fracture toughness test were performed. The results of the fracture toughness tests using the sub-sized specimens were compared with the evaluation technique of the ductile-brittle transition temperature.

• Journal of Korean Academy of Nursing
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• v.27 no.3
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• pp.627-638
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• 1997

Most patients having leukemia suffer severely from emotional turmoil due to the generalized perception that cancer will be fatal. The conventional chemotherapy results in side effects such as severe bone marrow depression which interfere with self-care management, vital for improvement in their condition. Bandura's theory of the self-efficacy suggests that self- efficacy can be enforced by performance attainments, vicarious experiences, verbal per-suasion and the release of emotional arousal. Self-efficacy can be enforced by a program of vicarious experiences and verbal persuasion, while the emotional arousal can be relieved through a hope promotion program, If once self-efficacy increases, the patient's self-care behaviors and the quality of life will also increase. The purpose of this study was to empirically test the effects of a program, to promote self-efficacy and hope, on self-care behaviors and quality of life in patients having leukemia. In this study, three types of approaches to enhance self-efficacy and hope were used : 1) a 20-minute long slide /tape for vacarious experiences : 2) a 10-minute long telephone call coaching for verbal persuasion ; and 3) two booklets for information about the symptoms of leukemia and treatment modalities and hope promotion. Thirty one patients were recruited in the experimental group and 29 in the control group with a nonequivalent pretest-posttest design. The subjects were patients with leukemia undergoing chemotherapy. Sherer and Maddux's self-efficacy scale, Nowotny's hope scale, and Padilla's quality of life scale were employed with some modifications. A self-care behavior scale was developed by the researchers. Statistical analyses including paired t-test, Chi-square, ANCOVA and ANOVA, were used. The results are as follows : The levels of self-efficacy, self-care behavior and quality of life were higher in the experimental group than in the control group after four weeks of intervention(F=28.71, P=.0001 ; F=63.35, P=.0001 F=16.57, P=.0001). After ten weeks of intervention, all of the dependent variables(self-efficacy, self-care behavior, hope & quality of life) in the experimental group were higher than in the control group (F=74.12, P=.0001 ; F=108.34, P=.0001 ; F=13,11, P=.001 : F=43.52, P=.0001). In conclusion, self-care behavior and quality of life increased mainly through an increase in self-efficacy, while increases in hope took more time and effort.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.19-35
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• 2021

Purpose : Recently, there has been a growing social interest in aging well. Consequently, wellness tourism has begun to attract attention. However, no studies on whether wellness tourism has any objective health benefits have been carried out yet. In this study, we assess the health benefits as well as the degree of improvement in health of a wellness tourism program. Methods : The study involved 30 adults over the age of 19 who live in the Gyeongsangnam-do region. Participants were evaluated on health indicator before and after participating in wellness tourism program. Participants took heart rate variability (HRV) test, and LFT, RFT, CBC, FBS HbA1C, and CRP test were conducted before and after the tour. Additionally, a survey was conducted before and after the program, and participant satisfaction was evaluated. Statistical differences in the tests conducted before and after the program were analyzed using a design t-test, a Wilcoxon signed-rank test, and McNemar's test. Results : The study showed that participants were very satisfied with and had significant health improvements after the wellness tourism program. The program was also found to be beneficial in improving participants' emotions as follows: BDI (p<.001), fatigue recovery (p=.006), stress relief (p=.003), improved quality of life (p<.05), and improved sleep quality (p<.001). Conclusion : Wellness tourism programs are specifically beneficial for improving participants' emotions (depression, anxiety), fatigue, stress levels, quality of life, and sleep. Therefore, they are beneficial to the overall health. Further research in the future by way of a follow-up study on the long-term effects on health after short-term interventions will provide more validation data.

• Asian Oncology Nursing
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• v.8 no.1
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• pp.50-60
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• 2008

Purpose: The purpose of this study was to compare Quality of life (QOL) in type and time after Hematopoietic stem cell tansplantation (HSCT) for patients with hematologic cancer. Method: This study was cross-sectional. The autologous recipients was 120, the allogeneic recipients was 237. The obtained data were analyzed using T-test, One-way ANOVA, Scheffe's test. Results: No significant differences were total QOL between the autologous and allogeneic recipients. But the autologous recipients reported better status than the allogeneic recipients in physical domain, especially 1-3 yr after HSCT. There was poorer QOL of 1-3 yr compared to 1 yr after HSCT in physical, psychological and social domain between the two groups. QOL in time after HSCT of the autologous recipients was significance differences in psychological, social domain. And QOL in time after HSCT of the allogeneic recipients was significant differences in physical, psychological and social domain. Conclusions: QOL of recipients undergoing HSCT is recovered beyond 3 yr point. Accordingly, long term care and service is essential to recipients undergoing HSCT. And further studies with a longitudinal design are necessary.

• Journal of Korean society of Dental Hygiene
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• v.16 no.3
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• pp.363-371
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• 2016

Objectives: The purpose of the study was to investigate the relationship between oral health perception and oral health-related quality of life-14(OHIP-14) in a geriatric hospital. Methods: A self-reported questionnaire was completed by 230 elderly people in a long-term care institution. The questionnaire was consisted of items on general characteristics, oral health perception and OHIP-14. Except incomplete answers, 226 data were analyzed statistically with one-way ANOVA, t-test, Pearson's correlation coefficient and post hoc Tukey test and ANOVA when significance was set at 0.05. Results: The OHIP-14 showed a negative linear relationship(p<0.01) of r=-0.272 with the oral health perception. Among the subgroups of the OHIP-14, quantitative linear relationship(p<0.01) was shown in functional limitation(r=0.822), physical pain(r=0.825), psychological discomfort(r=0.568), physical disability(r=0.895), psychological disability(r=0.652), social disability(r=0.804) and handicap(r=0.818). Conclusions: In order to improve the oral health perception and OHIP-14 in a geriatric hospital, it is necessary to develop continuously a variety of oral health education and systematic oral health promotion program.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.5
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• pp.23-30
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• 2007

This research was to evaluate the shrinkage and durability performance of latex modified repair mortar and to improve the service lift of the agricultural concrete structures. The shrinkage characteristics of the repair material creates the delamination of repair materials and existing concrete. It may reduce the service life of structures. Also the reduction of durability performance of the repair materials induces the destruction of the repaired concrete structures at early stage. In this research, plastic and drying shrinkage, thermal expansion coefficient for shrinkage properties, durability performance, permeability, repeated freezing and thawing, and resistance of chemical solution test were performed. Test results showed that the latex modified repair mortar indicated the shrinkage amount which the delamination does not happen, and the latex modified repair mortar appeared excellent long-term durability performance which can increase the service life.

• The Korean Journal of Applied Statistics
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• v.8 no.2
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• pp.121-132
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• 1995

In this paper we consider optimal designs of partially step-stress life testing which is deviced for k-component series systems with the considerably long life time. Test items are first run simultaneously at use condition for a specified time, and the surviving items are then run at accelerated condition until a predetermined censoring time. The optimal criterion for the change time to accelerated condition is to minimized either the generalized asymptotic variance of maximum likelihood estimators of the hazard rates at use condition and the acceleration factors or the asymptotic variance of the maximum likelihood estimators of the acceleration factors.

• Tribology and Lubricants
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• v.15 no.2
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• pp.150-155
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• 1999

The rolling fatigue lives (RFL) of five kinds of silicon nitride balls were investigated. Four kinds of Si$_3$N$_4$balls were fabricated using different raw materials, sintering aids and sintering conditions. Commercially available Si$_3$N$_4$ball was also studied for comparison. All the balls were finished up to the dimensional accuracy of Grade 10 defined in KS B 2001 (Steel Balls fer Ball Bearings) with a size of 9.525 mm. RFL tests were then conducted under the initial theoretical maximum contact stress 6.38 GPa and the spindle speed 10,000 rpm. Gear oil was provided by oiled race as lubricant. The results of RFL test indicated the prerequisitic conditions for the long rolling life of Si$_3$N$_4$ball : (1) the high density, (2) microstructures consisted of small uniformly distributed grains, (3) little glassy phase in grainboundary, and (4) little crystalline phase and secondary phase that induces residual thermal stress due to the differences of thermal expansion coefficient with Si$_3$N$_4$phase.

• Korean Journal of Materials Research
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• v.25 no.10
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• pp.516-522
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• 2015

Aging aircraft structures are inevitably exposed to environment for a long time facing many potential problems, including corrosion and wide spread fatigue damage, which in turn cause the degradation of flight safety. In this study, the environmental surface damages on aging aircraft structures induced during service were quantitatively analyzed. Additionally, S-N fatigue tests were performed with center hole specimens extracted from aging aircraft structures. From the results of quantitative analyses of the surface damages and fatigue tests, it is concluded that corrosion pits initiated during service reduce the fatigue life significantly. Finally, using the fracture mechanics and the EIFS (equivalent initial flaw size) concepts, the remaining fatigue life was predicted based on actual fatigue test results.