• Steel and Composite Structures
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• v.46 no.4
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• pp.451-469
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• 2023

The use of precast hollow-core slabs (PCHCS) in civil construction has been increasing due to the speed of execution and reduction in the weight of flooring systems. However, in the literature there are no studies that present a finite element model (FEM) to predict the load-slip relationship behavior of pushout tests, considering headed stud shear connector and PCHCS placed at the upper flange of the downstand steel profile. Thus, the present paper aims to develop a FEM, which is based on tests to fill this gap. For this task, geometrical non-linear analyses are carried out in the ABAQUS software. The FEM is calibrated by sensitivity analyses, considering different types of analysis, the friction coefficient at the steel-concrete interface, as well as the constitutive model of the headed stud shear connector. Subsequently, a parametric study is performed to assess the influence of the number of connector lines, type of filling and height of the PCHCS. The results are compared with analytical models that predict the headed stud resistance. In total, 158 finite element models are processed. It was concluded that the dynamic implicit analysis (quasi-static) showed better convergence of the equilibrium trajectory when compared to the static analysis, such as arc-length method. The friction coefficient value of 0.5 was indicated to predict the load-slip relationship behavior of all models investigated. The headed stud shear connector rupture was verified for the constitutive model capable of representing the fracture in the stress-strain relationship. Regarding the number of connector lines, there was an average increase of 108% in the resistance of the structure for models with two lines of connectors compared to the use of only one. The type of filling of the hollow core slab that presented the best results was the partial filling. Finally, the greater the height of the PCHCS, the greater the resistance of the headed stud.

• Journal of Korean Clinical Nursing Research
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• v.16 no.2
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• pp.107-116
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• 2010

Purpose: The purpose of this study was to examine the effects of a self-management program on self-efficacy and quality of life for Korean women with rheumatoid arthritis. Methods: A quasi-experimental study using a nonequivalent control group pretest posttest design was used. The data were collected from July 1 to Sep. 15, 2007. Thirty one arthritis patients (15 in the experimental group and 16 in the control group) were participated in this study. A self-management program developed by Korean Society of Muscle and Joint Health in 1994 was used. The program was consisted of 6 sessions, 2 hours each and held every Friday for 6 weeks. General Self-Efficacy Scale and Quality of Life were used to test the effect of the program. Results: Hypothesis 1; "Self-efficacy in the experimental group after program would be higher than the control group" was supported. Hypothesis 2; "Quality of Life in the experimental group after program would be higher than the control group " was not supported. Conclusion: The self-management program was effective for Korean women with rheumatoid arthritis in terms of increasing self-efficacy. Therefore, to increase self-management skills and self-efficacy for female rheumatoid arthritis patients, the program can be useful.

• Earthquakes and Structures
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• v.24 no.6
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• pp.439-453
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• 2023

Older brick masonry structures generally suffer from low strength defects. Using a cement mortar layer (CML) or steel-meshed cement mortar layer (S-CML) to reinforce existing low-strength brick masonry structures (LBMs) is still an effective means of increasing seismic performance. However, performance indices such as lateral displacement ratios and skeleton curves for LBMs reinforced with CML or S-CML need to be clarified in performance-based seismic design and evaluation. Therefore, research into the failure mechanisms and seismic performance of LBMs reinforced with CML or S-CML is imperative. In this study, thirty low-strength brick walls (LBWs) with different cross-sectional areas, bonding mortar types, vertical loads, and CML/S-CML thicknesses were constructed. The failure modes, load-carrying capacities, energy dissipation capacity and lateral drift ratio limits in different limits states were acquired via quasi-static tests. The results show that 1) the primary failure modes of UBWs and RBWs are "diagonal shear failure" and "sliding failure through joints." 2) The acceptable drift ratios of Immediate Occupancy (IO), Life Safety (LS), and Collapse Prevention (CP) for UBWs can be 0.04%, 0.08%, and 0.3%, respectively. For 20-RBWs, the acceptable drift ratios of IO, LS, and CP for 20-RBWs can be 0.037%, 0.09%, and 0.41%, respectively. Moreover, the acceptable drift ratios of IO, LS, and CP for 40-RBWs can be 0.048%, 0.09%, and 0.53%, respectively. 3) Reinforcing low-strength brick walls with CML/S-CML can improve brick walls' bearing capacity, deformation, and energy dissipation capacity. Using CML/S-CML reinforcement to improve the seismic performance of old masonry houses is a feasible and practical choice.

• Journal of Industrial Convergence
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• v.21 no.8
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• pp.129-136
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• 2023

The purpose of this study was to test the effects of simulation-based delivery nursing practice on proactivity of problem-solving, clinical Performance and team efficacy in nursing college students. This study conducted with a quasi-experimental one group pretest-posttest design. The subjects of the study were those who participated in the pretest-posttest survey among third graders in nursing who took a simulation-based delivery nursing practice class at S university in D city, and finally, data from 78 students who completed the survey were analyzed. Data collection was conducted from August 30, 2022 to October 28, 2022, and data were analyzed using SPSS 27.0 program. The findings suggest that simulation-based delivery nursing practice had a positive effect by significantly increasing on problem-solving proactivity, clinical performance ability, and team efficacy. However, There are limitations in generalizing the study results. therefore based on a sufficient number of samples, the effects should be verified through randomized controlled pre-and post-test and, To determine whether the effects are consistent, it will be necessary to follow up in the long term.

• Journal of muscle and joint health
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• v.30 no.3
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• pp.254-262
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• 2023

Purpose: This study was to determine the effect of Individualized education-counseling program on the performance of Health behavior and Cardiovascular risk after discharge inpatients with percutaneous coronary intervention. Methods: This study is a quasi-experimental study of the non-equivalence control group and the subjects of this study were patients who underwent percutaneous coronary intervention for coronary artery disease and had no complications due to severe arrhythmia or heart failure. The purpose of the study was explained to the subjects who met the selection conditions, and written consent was obtained, and 50 randomized experimental groups and 50 control groups were selected and assigned. Results: Compared to the control group, health behaviors were significantly higher after 1 week (F=33.63, p<.001) and 12 weeks (F=23.63, p<.001). The cardiovascular risk score based on Framingham risk score differed significantly depending on the measurement period (F=26.18, p<.001), there was no significant difference in the interaction between the two groups and the measurement period (F=0.72, p=.469). Conclusion: It was confirmed that the Individualized education counseling program provided to patients with Percutaneous coronary intervention was effective in increasing the subject's health behavior, but not in lowering the cardiovascular risk.

• Journal of East-West Nursing Research
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• v.30 no.1
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• pp.51-59
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• 2024

Purpose: The purpose of this study was to determine the effect of preoperative guidance and operating room environment experience using virtual reality on increasing satisfaction with information and reducing anxiety in preoperative patients undergoing general anesthesia and local anesthesia. Methods: A non-equivalent control group quasi-experimental design was employed. The participants were 80 surgical patients from 4 wards (40 experimental group and 40 control group) of the general hospital located in Gyeonggi-do. Data collection was conducted from June to November 2023 after completing the control group survey in January 2023. Data were analyzed using Chi-square, t-test, and Mann-Whitney U test using SPSS 23.0 program. Results: Satisfaction with preoperative information was higher in the experimental group than that of the control group. Additionally, anxiety related to surgery in the experimental group was significantly lower than that of the control group. The preoperative state anxiety score in the experimental group was not significantly lower than that of the control group. Conclusions: These results suggest that providing patient education and information using virtual reality technology can not only alleviate patients' anxiety related to surgery, but also have the potential to be used as an effective intervention to improve positive patient experiences.

• Women's Health Nursing
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• v.7 no.2
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• pp.188-202
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• 2001

This study was designed to investigate the effect of one-to-one labor support on labor pain, labor stress response, childbirth experience and neonatal status for primipara by a quasi experiment (nonequivalent control group pretest-posttest design), from April 30, 1999 to February 20, 2000. The subjects of this experiment consisted of eighty two primipara with single gestation, full term, uncomplicated pregnancies. Forty one were in the experimental group and forty one in the control group. Their mean age was 25.95 years, their mean gestation period was 39.9 weeks. A caring package of one-to-one labor support had three components. Physical support consisted of massage, back pressure, touch. Emotional support was provided by a continuous nurse's presence, acceptance and encouragement. Informational support involved teaching breathing skills, relaxation skills and knowledge about the labor process. Data assessed labor pain, pulse rate and blood pressure to measure labor stress response. Also, in measuring the value of labor stress response, plasma epinephrine, plasma norepinephrine and serum cortisol were measured. In the 24 hours after birth, the data for the postpartum mother's childbirth experiences was collected. Umbilical cord arterial blood pH, one minute and five minute Apgar score were measured after birth. Data was analyzed by t-test, $x^2$-test, repeated measures ANOVA, ANCOVA with SAS Program. The results were as follows; 1. Labor pain was significantly low in the experimental group(P=.016). 2. No significant group effects were found, but significant time effects were found for plasma epinephrine, norepinephrine, serum cortisol, pulse rate and blood pressure. 3. The childbirth experience of the experimental group was significantly more positive than the control group (P = .005). 4. The umbilical cord arterial blood pH of the experimental group was significantly higher than the control group(P=.014). There was no significant difference between the two groups in neonatal one minute and five minute Apgar scores. In conclusion, these findings indicate that one-to-one labor support could be effective in decreasing labor pain, and increasing positive childbirth experiences, also increasing the neonatal umbilical cord arterial blood pH for primipara. So, one-to-one labor support could be applied as an effective nursing treatment for primipara.

• Journal of the Korean Geographical Society
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• v.43 no.3
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• pp.324-336
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• 2008

This paper examines the recent changes of summer precipitation in the aspect of temporal and spatial features using long-term($1958{\sim}2007$) observed station data over South Korea. tong-term mean summer precipitation has revealed two precipitation peaks during summer(June to September); one is the Changma as the first peak, and the other is the post-Changma as the second peak. During the Changma period, the spatial distribution of the maximum precipitation areas is determined by the prevailing southwesterlies and the quasi-stationary front, which results in large amount of precipitation at the windward side of mountain regions over South Korea. However during the post-Changma period, the spatial distribution of the maximum precipitation areas is determined by the lower tropospheric circulation flows from the west and the southeast around the Korean peninsula, and the weather phenomena such as Typhoons, convective instability, and cyclones which are originated from the Yangtze river. The larger amount of precipitation is founded on the southern coastal region and mountain and coastal areas in Korea during the second peak. Time series of total summer precipitation shows a steady increase and the increasing trend is more obvious during the recent 10 years. Decadal variation in summer precipitation indicates a large increase of precipitation, especially in the recent 10 years both in the Changma and the post-Changma period. However, the magnitude of change and the period of the maximum peak presents remarkable contrasts among stations. The most distinct decadal change occurs at Seoul, Busan, and Gangnueng. The precipitation amount is increasing significantly during the post-Changma period at Gangnueng, while the precipitation increases in the period between two maximum precipitation peaks during summer at Seoul and Busan.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.5
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• pp.527-533
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• 1999

Hertzian indentation tests with spherical indenters in water were conducted to examine the contact fatigue in three dental ceramics, such as feldspathic porcelain, micaceous glass-ceramic (MGC) and glass-infiltrated alumina, which was used as dental restorations, and evaluated the effect of contact damage on strength. Initial damage was dependent of microstructure, showing cone cracks of brittle behavior in the feldspathic porcelain and deformation of quasi-plastic behavior in the MGC, with an intermediate case in the glass-infiltrated alumina. However, as increasing the number of cyclic loading (n=1~n =$10^6$)all materials showed an abrupt strength degradation, at which fracture was originated from damage in the contact fatigue. There were two strength degradation with increasing the number of cyclic loading in specific loads (200N, 500N, 1000N):first was from the cone cracks, and second was from the radial cracks created by cyclic loading. The radial cracks, once formed, led to rapid degradation in strength properties, Finally the material was failed at the high number of cyclic loading. Strength degradation with indentation load at fixed number of cyclic loading indicated that the feldspathic porcelain should be highly damage tolerant to the contact fatigue.

• Journal of muscle and joint health
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• v.12 no.2
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• pp.155-165
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• 2005

Arthritis is one of the most common chronic degenerative joint disease in elderly. Osteoarthritis is a widespread, slowly developing disease, with a high prevalence increasing with age in women. The large joints mostly involved by the disease are the knees. But there are no treatments available that cure the underlying process of osteoarthritis diseases. Physical exercise helps in increasing cartilage nutrition and remodeling, increases the synovial blood flow, decrease swelling, and improves muscle strength. Thus, exercise has been suggested as an important nursing strategy in osteoarthritis. Purpose: The purpose of this study were to compare muscle strength between Tai-Chi exercise and aquatic exercise for women with knee osteoarthritis. Methods: A quasi-experimental study with pretest and posttest measures was used. The study subjects were those who had been enrolled in a community health center, and agreed to participate in the study for eight weeks, signed the consent form, and obtained the physicians approval. The study dropout rates were 13.2% with the final study subjects of 17 on Tai-Chi exercise, 16 on aquatic exercise program. The collected data were analyzed using SPSS for Window (version 12.0). Independent sample t-test and paired t-test was performed to compare of muscle strength for women with osteoarthritis after 8-week Tai-Chi exercise and aquatic Exercise. Results: The homogeneity tests of demographic characteristics and study variables at the pretest data revealed no significant differences between two groups. After 8-week Tai-Chi and aquatic exercise, there was significant result in pre-post test comparison on muscle strength on Tai-Chi group, but no significant in aquatic group. There were no significant differences of knee extensor (p=.078), and hand grip(p=.118) in group comparisons on muscle strengths. But there were significant differences of knee flexor(p=.024). Conclusion: Tai-chi exercise was effective in improving knee flexor. So, it seems that Tai-chi exercise may be more suitable for aquatic exercise in osteoarthritis exercise programs. Further studies with other comparisons in physical and psycho social outcomes are necessary to confirm the more effects of exercise.