• International Journal of Highway Engineering
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• v.8 no.3 s.29
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• pp.49-61
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• 2006

This study suggests long-life asphalt pavement method which can save maintenance cost by increasing the design and performance period of pavements. The high modulus asphalt binder developed and then various physical tests are performed. Laboratory performance tests and accelerated pavement test are conducted for the high modulus and conventional mixtures. The test results show that dynamic modulus values of high modulus mixtures are higher than those of the conventional mixtures, The high modulus mixtures yield better fatigue, rutting and moisture damage performance than conventional mixtures. Structural analysis is performed and a database is built up for long life asphalt pavement design. Pavement response model is developed through a multiple regression analysis program, SPSS using the database. A design software for the long life pavements is developed based on the pavement response model and laboratory and field performance tests results. In addition, optimum pavement sections and materials are suggested. The suggested AC thickness of long life asphalt pavement is 29cm. A Life cycle cost analysis(LCCA) is conducted to check the economical efficiency of the long life pavement section. The LCCA result shows that initial construction costs of long life and conventional pavements are almost equal, but long life pavement is more profitable in terms of the LCCA.

• Journal of Hospice and Palliative Care
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• v.24 no.1
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• pp.26-35
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• 2021

Purpose: The purpose of this study was to determine the effects of awareness of good death and end-of-life care attitudes on end-of-life care performance in long-term care hospital nurses. Methods: This study used a cross-sectional study design. The participants were 147 nurses working at six long-term care hospitals with more than 200 beds in B city, South Korea. Data were collected using self-reported questionnaires, and analyzed with descriptive statistics, the t-test, analysis of variance, Pearson correlation coefficients, and multiple stepwise regression analysis using IBM/SPSS 26.0 for Windows. Results: The participants' awareness of good death, end-of-life care attitudes, and end-of-life care performance were positively correlated. The factors affecting end-of-life care performance were age, education level, awareness of good death, and end-of-life care attitudes; these variables explained 19.0% of end-of-life care performance. Conclusion: In order to improve long term care hospital nurses' end-of-life care performance, continuing education and training should be provided regarding awareness of good death and end-of-life care attitudes.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1058-1062
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• 2004

High-temperature cylindrical stainless steel/sodium heat pipe was manufactured and tested under long-term operation. The container material was stainless steel 316L and the working fluid was sodium. The heat pipe was 25.4 mm in diameter and 1000 mm in length with a two-layer screen mesh wick. The evaporator part was 600 mm and the condenser part was 300 mm in length. Total measurement points on heat pipe were 15 points and 12 points were located in condenser part. The heat pipe was heated for 142 days(3400 hours) at $800^{\circ}C$. In the test period, the maximum temperature difference was increased from $18^{\circ}C$ o $28^{\circ}C$ and the maximum thermal resistance was as low as $0.015^{\circ}CW$.

• Journal of the Korean Society of Safety
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• v.33 no.3
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• pp.8-14
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• 2018

Ni-base superalloy has excellent resistance to extreme environments such as high temperatures and high stresses and are used as materials for large gas turbines. In this paper, the specimens were taken from the blade that were used for a long time, and their life span was studied by microstructure analysis and avoidance of cursing. The microstructural analysis of the specimens was carried out using a OM and SEM to observe the coarsening, carbides on gamma prime. Low-cycle fatigue tests were performed on new material and airfoil of long time-used blade. The test was conducted under various deformation conditions and temperature conditions of $760^{\circ}C$ and $870^{\circ}C$. The low cycle fatigue test was carried out using the Coffin-Manson equation and the fatigue life was predicted. After the test, crack path and fracture surface were analyzed using SEM.

• The KSFM Journal of Fluid Machinery
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• v.15 no.2
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• pp.51-56
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• 2012

The butterfly valve has been used over all industries. It has been studied to improve its performance through the theoretical analysis and the test in industry. Though products adopted those improvements have been sold in markets, manufacturers often launch products without the life test. One reason is because of the long development period and financial difficulties. The other is the lack of the design and fabrication experiences on building the life test equipment. Thus, this study has been researched for the design and fabrication of our life test equipment, and developed and improved the equipment to check the leakage of the valve with the naked eyes during the test.

• 연구논문집
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• s.34
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• pp.79-85
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• 2004

There are several types of life test method for hose assemblies. The two major tests used for hose assemblies are impulse test and burst test. And magnification adjustment of impulse pressure, heating of testing oil and repetitive motions of bending and straightening of testing hose are also performed for accelerating the life. According to the manufacture process of hose and swaging process of fitting, there is a difference in the life of hose assemblies from minimum 7 times to maximum 40 times during the life test in the same functioning condition. Like this, the life test of hose which has a wide scope of life distribution gives a problem that observation should take a long time to find out the existence of the bursting from the beginning of the test to the completion of bursting of hose assemblies. Therefore, this research proposes a process of concentrating on the defective section of hose assemblies and maximizing the life acceleration by giving 'Knockdown stress' to hose assemblies just until before the hose assemblies get out of order.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.227-237
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• 2021

The aim of this study is to identify the influence of care services on the quality of life of elderly residents in long-term care facilities, and to determine the mediating effect of family support. The subjects of the study were 192 older adults living in long-term care facilities in the Daegu and Gyeongsangbuk-do region. The collected data were analyzed using the SPSS 22.0 program, and the methods used include descriptive statistics, t-test, ANOVA, Pearson correlation analysis, and regression analysis. The results of the study found that the subjects' quality of life differed depending on their age, education, income level of their children, reasons for admission, and length of stay. The factors that influenced their quality life included age, education, the income level of their children, reasons for admission, length of stay, and care services. The study also revealed that family support was the mediating effect in the relationship between care services and quality of life. The results of the study will provide insight in establishing a nursing intervention plan to improve the quality of life of elderly residents in care facilities.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.211-212
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• 2019

It is possible to realize the concept of long-life housing by utilizing the wall piping infill system. However, when using the wall piping infill system, there is no detailed standard in Korea. Problems may occur in actual use. In this study, we use the results obtained from the performance test method as a basic data. Since the load resistance test of the toilet is not available in Korea, GB 6952 (Sanitary wares) of China is applied. According to the experiment of load resistance of the toilet in this study, the strain recovery ability was good. However, it is not possible to exclude the possibility of permanent deformation of the toilet seat due to long - term repeated loading. Therefore, it is necessary to consider the stiffness enhancement of the wall (steel frame) to the fixing part when installing the toilet in the wall pipe infill system.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2271-2279
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• 1993

In the case of life prediction on the structures and machines after long service, it is natural to consider a degradation problems. Most of degradation data form practical structures are isolated data obtained at the time of periodical inspection or repair. From such data, it may be difficult to obtain the degradation curve available and necessary for life prediction. In this paper, for the purpose of obtaining a degradation curves, developed the simulate degradation method and fatigue test and Charpy impact test were conducted on the degraded, simulate degraded and recovered materials. Fatigue life prediction were conducted by using the relationship between fracture transition temperature (DBTT : vTrs) obtained from the Charpy impact test through the degradation process and fatigue crack growth constants of m and C obtained from the fatigue test.

• Korean Journal of Pharmacognosy
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• v.43 no.2
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• pp.147-151
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• 2012

The marker constituent was isolated from Rubia cordifolia as a major compound. Quantitative method for the marker of the natural medicine was developed using HPLC-DAD and using established method the extract of Rubia cordifolia was evaluated. In addition, long term and accelerated stability test in the extract was examined for six months. No significant change in content of the marker constituent of the extract observed during the period of long term test.