• Computers and Concrete
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• v.30 no.5
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• pp.301-310
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• 2022

Cement-based sensors have been widely used as structural health monitoring systems, however, their long-term sensing performance have not actively investigated. In this study, a deep learning-based methodology is adopted to predict the long-term piezoresistive properties of cement-based sensors. Samples with different multi-walled carbon nanotube contents (0.1, 0.3, and 0.5 wt.%) are fabricated, and piezoresistive tests are conducted over 10,000 loading cycles to obtain the training data. Time-dependent degradation is predicted using a modified long short-term memory (LSTM) model. The effects of different model variables including the amount of training data, number of epochs, and dropout ratio on the accuracy of predictions are analyzed. Finally, the effectiveness of the proposed approach is evaluated by comparing the predictions for long-term piezoresistive sensing performance with untrained experimental data. A sensitivity of 6% is experimentally examined in the sample containing 0.1 wt.% of MWCNTs, and predictions with accuracy up to 98% are found using the proposed LSTM model. Based on the experimental results, the proposed model is expected to be applied in the structural health monitoring systems to predict their long-term piezoresistice sensing performances during their service life.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.481-486
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• 2003

This paper presents experimental study on long-term behavior of RC and SRC columns. Shrinkage and creep tests were performed for two types of concrete used in manufacturing RC and SRC column specimens. Also, long-term tests under sustained load were carried out for RC and SRC column specimens. Shrinkage functions and creep coefficients to optimally fit the corresponding data were obtained from regression analysis and the regression results, ACI and CEB- FIP 90 model were applied to analyse long-term behvavior of RC and SRC column specimens. Creep coefficients calculated from test data were lower than those predicted by ACI and CEB-FIP 90 models. Long-term analysis results for RC and SRC column specimens using the regression results were relatively more accurate than those obtained using the existing models.

• Journal of the Korean Wood Science and Technology
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• v.17 no.4
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• pp.35-43
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• 1989

Nailed joints, which are commonly used in Wooden structures, transmit loads from one member to another and induce partial composite actions between members. Long-term loads induce creep slip in nailed joints and affect load sharing and partial composite action, which may reduce joint stiffness. Two theoretical viscous-viscoelastic models were developed for nailed joints to predict creep behavior under long-term variable loads. Those models were also used to predict stiffness changes under long-term variable loads. The stiffness of nailed joint is defined as a Secant modulus which is called the joint modulus or slip modulus. Input data for the models are the results of constant load tests under three different load levels. To verify the models, nailed joints were also tested under two long-term variable load functions. The predictions of the models were very close to the experimental data. Therefore, the theoretical viscous-viscoelastic models and procedures developed in this study can be applied to predict creep slip and the changes in joint moduli of nailed joints under long-term variable loads.

• Journal of Haehwa Medicine
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• v.27 no.1
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• pp.1-8
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• 2018

Objectives : The purpose of this study was to analyze the status of inpatients in long-term care hospital and the satisfaction of Korean medical treatment. Methods : These analyzed data were collected from patients who were hospitalized in long-term care hospital in Sejong from Jan. 1. 2017 to Dec. 31. 2017. To analyze the status and the satisfaction of inpatients, we calculated the data of inpatients and conducted a survey. Results : Preference for acupuncture treatment was 95.6% and preference for numbers of Korean medical treatment more than two times per week was 40%. In addition, confidence in Korean medical treatment was 4.31, improvement after Korean medical treatment was 4.07 and general satisfaction was 4.58 with five-point scale. Conclusions : Most of the patients in long-term care hospital were satisfied with Korean medical treatment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1271-1279
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• 2013

In this paper, a study on the prediction method of basic wind speed at the construction site of long-span bridge using short-term measurements was conducted. To determine the basic wind speed in the wind resistant design for the long-span bridge away from the weather station, statistical analysis of long-term data at site is required. Wind observation mast was installed at site, and short-term measurements were gathered and the correlation analysis between the site and the station was done using regression analysis and MCP(Measure-Correlate-Predict). The long-term wind data of the site was obtained from correlation formula after topographical revision of long-term data of the station. And basic wind speed could be estimated by extreme probability distribution analysis. The research results show that the wind speed by regression analysis is predicted lower than by MCP and after this study a series of correlation analyses at several sites will show clearly the difference two methods. And also a quality control of long-term wind data is very important in estimation of wind speed.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.27 no.1
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• pp.5-15
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• 2020

Purpose: To identify the relationship between care worker's awareness of human rights and the compliance of caring behaviors among long-term care workers, and to identify factors affecting compliance with caring behaviors. Methods: Using self-report questionnaires, data were collected from 153 long-term care workers between October 4th and October 20th, 2019. Collected data were analyzed using the SPSS/WIN 26.0 program. Results: The data indicate a difference in awareness of human rights according to: the careers of care workers, the possession of other health care-related licenses, and the perceived needs of human rights education. The data also indicate a difference in the compliance of caring behaviors according to: gender, family care experience, and dementia care experience. The factors influencing compliance of caring behaviors, according to the study, are gender (β=.19, p=.009), family care experience (β=.19, p=.023), and human rights (β=.38, p<.001). It was found that 23% could explain the compliance of caring behaviors. Conclusion: Long term care workers were found to have a higher level of the compliance of caring behaviors as their awareness of human rights increased. In order to increase the compliance of caring behaviors among long-term care workers, more educational programs on human rights should be provided.

• Journal of the Korean Solar Energy Society
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• v.33 no.5
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• pp.1-8
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• 2013

Wind resource data of short-term period has to be corrected a long-term period by using MCP method that Is a statistical method to predict the long-term wind resource at target site data with a reference site data. Because the field measurement for wind assessment is limited to a short period by various constraints. In this study, 2 different MCP methods such as Linear regression and Matrix method were chosen to compare the predictive accuracy between the methods. Finally long-term wind speed, wind power density and capacity factor at the target site for 20 years were estimated for the variability of wind and wind energy. As a result, for 20 years annual average wind speed, Yellow sea off shore wind farm was estimated to have 4.29% for coefficient of variation, CV, and -9.57%~9.53% for range of variation, RV. It was predicted that the annual wind speed at Yellow sea offshore wind farm varied within ${\pm}10%$.

• KDI Journal of Economic Policy
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• v.31 no.1
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• pp.139-167
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• 2009

A new public insurance for long-term care was introduced in July 2008 to provide for the rising demand for long-term care as the population is aging rapidly. The demand for long-term care is expected to rise further because more and more elderly are living alone or in households with only other elderly, such as his/her spouse, without informal care of their adult children. Even when the elderly are living together with their adult children, daughters and daughters in law, once the main informal care-givers, are not available because they choose to become economically active and work more over time. Experiences of countries such as Japan and Germany with similar public long-term care insurance scheme highlight the importance of detailed analysis on the demand for long-term care for the financial stability of the insurance scheme. Countries which had underestimated the demand for long-term care at the time of adopting the scheme went through financial instability of insurance schemes. This study analyzes the determinants of the demand for long-term care using data from the second demonstration project (April 2006~April 2007) of the long-term care insurance scheme for the elderly in Korea. Taking full advantage of detailed data on the long-term care, this paper analyzes the eligibility for the long-term care insurance scheme and its use. According to study results, even when common diseases among the elderly such as cancer, diabetes, arthritis, dementia, hypertension, etc. are controlled together with other individual and socioeconomic factors, limitations the elderly are faced with in their twelve activities of daily living significantly affect the eligibility for the Korean Long-term Care Insurance Scheme. This means that limitations in daily living activities are more critical than common diseases among the elderly are to the eligibility for the Korean Long-term Care Insurance Scheme. Bathing and toileting problems have been found to be the most important factor affecting the eligibility for the insurance scheme, followed by eating, dressing and moving around inside the house. Moreover, the choices of whether to use long-term care and which to use between home care and institutional care are found to be significantly influenced by health status and various socioeconomic factors of the elderly. In particular, those with more limitations in daily living activities and the female elderly are more likely to use long-term care and institutional care rather than home care. As for home care users, those living alone or with adult children and those with monthly household income of more than 500,000 won are more likely to use home care. Most importantly, even when the monthly household income of the elderly is controlled, the elderly recipients of the National Basic Living Security, who are not charged for long-term care, are more likely to choose home care. This implies that price as well as income is a critical factor for the decision to use long-term care. Further study on the duration of long-term care use will surely enhance the long-term care policy, when panel data is available for simultaneous analysis of the likelihood of long-term care use and its use duration.

• Journal of East-West Nursing Research
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• v.26 no.1
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• pp.63-70
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• 2020

Purpose: The purpose of this study was to compare the moral distress and burnout between long-term care hospital nurses and general nurses. Methods: This study was a cross-sectional survey. Participants were 193 nurses (long-term care hospital 95, general hospital 98) working in a hospital in Seoul, Daegu and Busan city. Data were collected from October 02 to November 30, 2018 using a structured questionnaires and analyzed with SPSS/PC ver 21.0 programs. Results: The scores of moral distress by nurses working in long-term care hospitals were higher than those of nurses in general hospitals. The score of burnout by nurses working in general hospitals was significantly higher than that of nurses in long-term care hospitals. There was a significant positive relationship between moral distress and burnout in both long-term care hospital nurses and general hospital nurses. Conclusion: This research shows that long-term care hospital nurses have higher moral distress and burnout than those of general hospital nurses. Therefore, nursing managers and organization should strive to raise the perception of moral distress and burnout in long-term care hospital nurses.

• Korea Journal of Hospital Management
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• v.15 no.1
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• pp.49-69
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• 2010

The major purpose of this study is to find out relevant factors affecting utilization of Long Term Care Hospitals since the Elderly Long Term Care Insurance System was adopted in Korea. The sample hospitals of this study are 5 long term care hospitals located in 4 big cities and 1 local area. The research data were collected with structured questionnaire from 247 patients and patients' protectors in 5 sample hospitals. Analyzing methods are descriptive statistics, factor analysis and multiple regression with SPSS(version 12.0). Major results of this study are as follows. 1) Utilization and recommendation of patients is affected significantly by the level of hospital facilities (0.043), fee level(0.026), level of staff (0.000), and discomfort of services(0.001). 2) Level of staff is very positively correlated with utilization and recommendation of patients. 3) Discomport of services is very negatively correlated with utilization and recommendation of patients. On the basis of results this study conclude that the management of Long Term Care Hospitals is required conclude to improve the level of staff and facilities and to solve discomport problems of services for patients' marketing. And also more in-depth study on the utilization factors of long term care hospital in Korea is required.