• Steel and Composite Structures
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• v.30 no.6
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• pp.535-550
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• 2019

Prestressed concrete (PC) bridges using corrugated steel webbing have emerged as one of the most promising forms of steel-concrete composite bridge. However, their long-term behavior is not well understood, especially in the case of large-span bridges. In order to study the time-dependent performance, a large three-span PC bridge with corrugated steel webbing was compared to a similar conventional PC bridge to examine their respective time-dependent characteristics. In addition, a three-dimensional finite element method with step-by-step time integration that takes into account cantilever construction procedures was used to predict long-term behaviors such as deflection, stress distribution and prestressing loss. These predictions were based upon four well-established empirical creep prediction models. PC bridges with a corrugated steel web were observed to have a better long-term performance relative to conventional PC bridges. In particular, it is noted that the pre-cambering for PC bridges with a corrugated steel web could be smaller than that of conventional PC bridges. The ratio of side-to-mid span has great influence on the long-term deformation of PC bridges with a corrugated steel web, and it is suggested that the design value should be between 0.4 and 0.6. However, the different creep prediction models still showed a weak homogeneity, thus, the further experimental research and the development of health monitoring systems are required to further progress our understanding of the long-term behavior of PC bridges with corrugated steel webbing.

• Journal of Korean Society for Quality Management
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• v.30 no.3
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• pp.1-19
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• 2002

Greenberg(1990) suggested that organizational justice research may potentially explain many organizational behavior outcome variables. One example of nontraditional job behavior is service quality, for it is part of the spontaneous and innovative behaviors noted by Katz(1964). The first purpose of this research is to test the effects of organizational justice on service quality, and the second purpose is to test the moderating effects of sex and tenure on the relationships between organizational justice and service quality According to statistical analysis, only interactional justice had an impact on service quality. Also the results of moderating regression analysis showed that short term employees were more sensitive to distributive justice than long term employees. This result means short term employees are more interested In incentive system than long term employees.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.13-20
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• 2015

PURPOSES: This paper describes the expansion caused by the alkali-aggregate reaction (AAR) in concrete pavement currently in service. It also discusses the effects of joints installed to release the stress induced by the AAR expansion. METHODS: The expansion effect on concrete pavement was verified by a visual inspection and long-term measurement of the joint width of a cut-section. The behaviors of 16 newly installed joints were monitored as part of the investigation and long-term monitoring was carried out for three years after cutting. RESULTS: The behavior of a bridge was affected when AAR occurred in the connected pavement. The newly installed joints shrank in the longitudinal direction of the bridge after cutting. The width of the joints decreased over the six months after cutting. A large portion of the joint width (8.5cm) was found to have closed nine months after cutting. It had ultimately shrunk by about 92 percent when the final measurement was taken. CONCLUSIONS : The expansion of the pavement due to AAR was quantitatively described by visual inspection and the long-term monitoring of the newly cut joints. However, the width of the new joints decreased over the six to nine months after cutting. Additional research should be conducted to determine a means of controlling the expansion due to AAR in the pavement.

• Journal of Home Health Care Nursing
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• v.23 no.2
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• pp.155-165
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• 2016

Purpose: The purpose of this study was to investigate factors influencing health workers' infection management behavior in long-term care facilities. Methods: A descriptive cross-sectional survey was conducted with 180 health workers who are employed in long-term care facilities. The data were collected from April, 25 until July, in 2016. Results: Infection management behavior positively correlated with the perceived importance of infection management (r=.77, p<.001), but role conflict negatively correlated with infection management behavior (r=.28, p<.001). The hierarchical regression model with general characteristics (first step) and perceived importance of infection management, work environment, and role conflict (second step) against infection management behavior was statistically significant (F=31.93, p<.001). This model could explain 62.8% of infection management behavior ($R^2=.62$, ${\Delta}R^2=.39$). Particularly, perceived importance of infection management was identified as factors influencing infection management behavior(${\beta}=.70$, p<.001). Conclusion: The findings of this study imply that systemic education about infection control and monitoring should be considered, so as to encourage proper infection management behaviors among health workers in long-term care facilities.

• Korean Journal of Social Welfare
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• v.66 no.2
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• pp.5-29
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• 2014

The purpose of this study is to interpret how the long-term care evaluation system implements in the actual service settings with institutional isomorphism and decoupling based on new-institutional theory. This study conducted in-depth interview with employees engaged in 7 long term care service facilities. Directed qualitative content analysis was used to analyze the data. As a result, unlike the intention of the long-term care evaluation system to improve the efficiency of the organization by market competition, it found that organizations forcibly adapted a evaluation system to rely on government's resources and it results in isomorphism phenomena which is similar between organizations. This results confirmed that the evaluation system has implemented in the direction of enhancing the government's role to standardize and institutionalize the long-term care service rather than improving the efficiency of the organization by market competition. This study also partially found the phenomenon of decoupling between organizational formal structure accompanied by isomorphism and real behaviors. These results suggest that it is required to improve government's evaluation indicators on the issue of inefficiency caused by dual structure of organizations. In addition, this study proposes that government's evaluation index which is reflected the characteristics of care service is necessary for operating.

• Journal of the Korean GEO-environmental Society
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• v.24 no.11
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• pp.19-24
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• 2023

Ground anchor has been widely used specially for maintaining stability on reinforced cut slope in expressway. While the durability of the ground anchors should be ensured over the service life. However, the long-term loss of tensile force has occurred in most of field-installed anchors. Main causes are not clearly identified and very few studies have been made for analyzing long-term behavior of ground anchor in slopes. In this study, full-scale model tests and long-term measurements were made to obtain the load-displacement data and identified the causes of the long-term behaviors of ground anchor. As a result, the bond strength decreases exponentially with increasing water-binder ratio. Especially, groundwater is the most influencing factor to the bond strength. In the long-term behavior, the load decreases sharply until the initial settlement stabilized, and thereafter the tension force decreases constantly.

• Journal of the Korean Home Economics Association
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• v.43 no.7 s.209
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• pp.79-91
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• 2005

The purpose of the study was to examine the current status of financial management behaviors of college students and to determine the affecting factors. The data were collected from 481 college students in Busan and Kyungnam areas by a self-administered questionnaire. Frequencies, Cronbach's alpha, factor analysis Pearson's correlation analysis and regression analyses were conducted by SPSS WINDOWS. The results from this study were as follows. first, the mean of preparation for the future was the highest among 5 dimensions of money attitudes, whereas the mean of the ostentatious means was the lowest. In addition, the college students showed good practices in drawing up shopping lists, budgeting, and keeping receipts, but bad practices in short-term and long-term planning. Second, many factors such as gender, grade, mother's education, fathers' occupation, and mothers' occupation were significant in the regression analyses for the financial management behaviors. Especially, money attitudes and experience of consumer education were significant in many categories of financial management behaviors. In combination, these results suggest that financial management education for college students should be conducted, and that contents related to value should be included in the education program.

• Journal of Families and Better Life
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• v.24 no.4 s.82
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• pp.37-50
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• 2006

The purpose of this study is to analyze the determinants of financial behaviors and subjective economic well-being in personal financial education through research targeted at adults. The results indicated by the research can be summarized as follows. First, there was a significant difference found in the changes of financial behaviors in accordance with the types of financial education programs, the time period, and the methods of financial education. Second, financial behaviors were higher when participating in profit financial education programs or in workplace financial education programs. Additionally, the increase was higher when participating in long-term programs. Third, the positive effects on subjective economic well-being were financial behaviors, participation in profitable financial education programs, unmarried and income level.

• Journal of Korean society of Dental Hygiene
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• v.17 no.3
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• pp.527-537
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• 2017

Objectives: The purpose of this study was to examine the practice of oral hygiene behaviors and oral health status of long-term care facility residents and to analyze the factors related to salivary hemoglobin level which can predict active periodontal disease. Methods: From 30th October 2015 to 7th January 2016, a questionnaire was provided to 63 participants and their dental plaque and saliva samples were collected to assess the levels of salivary hemoglobin and dental plaque acidogenicity. In order to analyze the factors related to salivary hemoglobin level, multiple linear regression analysis was performed. Results: Toothbrushing was most frequently performed by the participants themselves (98.4%) and toothbrushing was performed after eating breakfast (81.3%). 68.8% of participants reported brushing their tongue. 35.9% of participants perceived having bad teeth, and 87.5% had high dental caries activity. The percentages of participants with hyposalivation and ${\geq}0.20{\mu}g/ml$ salivary hemoglobin level were 45.3% and 59.4%, respectively. The salivary hemoglobin level was significantly higher in the group in which stimulated salivary flow rate was ${\leq}0.70ml/min$, dental plaque acidogenicity was superior, and perceived having bad teeth (p<0.05). There was also a tendency for the salivary hemoglobin level to increase with age (p<0.05). Conclusions: Oral health status of the long-term care facility residents was still not improved, and the characteristics of salivary volume and dental plaque were important factors affecting salivary hemoglobin level. Therefore, it is necessary to operate an oral hygiene intervention program by oral health professionals in such facilities in order to provide residents with effective oral care aligned with their respective needs. Furthermore, it is necessary for caregivers to complete mandatory oral health education to improve the oral hygiene status of the long-term care facility residents.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.51.1-51.15
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• 2023

Background: Recently, there has been increasing worldwide concern about outdoor air pollution, especially particulate matter (PM), which has been extensively researched for its harmful effects on the respiratory system. However, sufficient research on its effects on cardiovascular diseases, such as hypertension, remains lacking. In this study, we examine the associations between PM levels and hypertension and hypothesize that higher PM concentrations are associated with elevated blood pressure. Methods: A total of 133,935 adults aged ≥ 40 years who participated in the Korean Genome and Epidemiology Study were analyzed. Multiple linear regression analyses were conducted to investigate the short- (1-14 days), medium- (1 and 3 months), and long-term (1 and 2 years) impacts of PM on blood pressure. Logistic regression analyses were conducted to evaluate the medium- and long-term effects of PM on blood pressure elevation after adjusting for sex, age, body mass index, health-related lifestyle behaviors, and geographic areas. Results: Using multiple linear regression analyses, both crude and adjusted models generated positive estimates, indicating an association with increased blood pressure, with all results being statistically significant, with the exception of PM levels over the long-term period (1 and 2 years) in non-hypertensive participants. In the logistic regression analyses on non-hypertensive participants, moderate PM₁₀ (particulate matter with diameters < 10 ㎛) and PM_2.5 (particulate matter with diameters < 2.5 ㎛) levels over the long-term period and all high PM₁₀ and PM_2.5 levels were statistically significant after adjusting for various covariates. Notably, high PM_2.5 levels of the 1 year exhibited the highest odds ratio of 1.23 (95% confidence interval: 1.19-1.28) after adjustment. Conclusions: These findings suggest that both short- and long-term exposure to PM is associated with blood pressure elevation.