• Journal of the Korean Society of Safety
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• v.34 no.4
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• pp.76-84
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• 2019

The precast pannels are used as formwork in Half-depth precast deck systems. Therefore, it has many advantages, including safe and convenient construction and reduced construction period compared to cast-in-place construction method. In half-depth precast deck systems, the bonding of precast pannels to cast-in place concrete is very important. To enhance the performance of half-depth precast deck system, it is necessary to improve the composite efficiency of the interface or increase the stiffness of the precast pannel to reduce deformation or stress on the interface. In this study, a flexural test of half-depth precast deck system was performed, in which the shear connecting reinforcement was applied to increase the bonding performance at the interface, and the rib shape precast panels were applied to improve stiffness. In addition, the safety and serviceability of these systems were evaluated. Test results show that all of specimens have the required flexural strength under the ultimate strength limit design. It was also evaluated to have sufficient safety for the serviceability of deflection and crack under the serviceability limit design.

• Journal of the Korean Solar Energy Society
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• v.28 no.5
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• pp.28-35
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• 2008

The aim of this study was to analysis the Heating/cooling performance of movable insulation system built in apartments. The process of this study is as follows: 1) Test-cells of movable insulation are designed through the investigation of previous paper and work. The type of the movable insulation used in test-cell is low emissivity(5%) insulation, measured for heating season and the thermal effects are analyzed. 2) The simulation program(Design Builder) was used in energy performance analysis. the reference model of simulation was made up to analysis energy performance on movable insulation system. 3) Selected reference model(Floors:15, Area of Unit:115.5$m^2$) for heating/cooling energy analysis, Energy performance simulation with various variants, such as slate angle of movable insulation(5$^{\circ}$, 30$^{\circ}$, 50$^{\circ}$) and position of movable insulation. Consequently, When movable insulation system is equipped with balcony window of Apartment, Annual heating energy of reference model was cut down at the average of 5.4kWh/$m^2$ or 4.6% of heating/cooling energy.

• Nuclear Engineering and Technology
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• v.39 no.4
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• pp.273-286
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• 2007

This paper presents the research activities performed to date for the development of a supercritical pressure water-cooled reactor (SCWR) in Korea. The research areas include a conceptual design of an SCWR with an internal flow recirculation, a reactor core conceptual design, a heat transfer test with supercritical $CO_2$, an adaptation of an existing safety analysis code to the supercritical pressure condition, and an evaluation of candidate materials through a corrosion study. Methods to reduce the cladding temperature are introduced from two different perspectives, namely, thermal-hydraulics and core neutronics. Briefly described are the results of an experiment on the heat transfer at a supercritical pressure, an experiment that is essential for the analysis of the subchannels of fuel assemblies and the analysis of a system safety. An existing system code has been adapted to SCWR conditions, and the process of a first-hand validation is presented. Finally, the corrosion test results of the candidate materials for an SCWR are introduced.

• Child Health Nursing Research
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• v.28 no.4
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• pp.259-268
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• 2022

Purpose: Nursing students are susceptible to medication safety incidents in the neonatal intensive care unit (NICU) related to a lack of communication experience. The purpose of the present study was to investigate the impact of a NICU medication safety simulation (NMSS) focusing on communication clarity, patient hand-off confidence, and patient safety competency in senior-year nursing students. Methods: The study utilized a nonequivalent control group pretest-posttest design. In total, 60 nursing students were assigned to two groups. The experimental group participated in the NMSS, which included three medication error scenarios. Pairs of students completed the scenarios together in 10 to 20 minutes. Data were analyzed using the chi-squared test, independent t test, and ANCOVA. Results: The experimental group showed significant improvements in communication clarity (p=.015), and patient safety competency (p<.001) compared to the control group. Using the pretest values as covariates, patient hand-off confidence scores significantly increased (p=.027). Conclusion: Implementing the NMSS focusing on communication in the pediatric nursing curriculum helped students to communicate clearly and concisely about medication errors, and its use is recommended to promote patient safety competency in the NICU.

• Physical Therapy Rehabilitation Science
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• v.12 no.2
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• pp.140-148
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• 2023

Objective: Meniscal injuries are a common and high-risk condition among military personnel, leading to difficulties in performing missions.The objective of this study is to investigate the effects of combining electrical muscle stimulation therapy with exercise therapy during rehabilitation on pain, muscle strength, and function in patients after meniscectomy. Design: A two-group pretest-posttest design Methods: A total of 30 subjects were included in this study. They were randomly assigned to either the experimental group (n=15), which received knee extensor strengthening exercise along with electrical muscle stimulation, or the control group (n=15), which received only knee extensor strengthening exercise. Pre-test was conducted prior to the intervention, which consisted of 30 minutes of treatment five times a week for a total of 20 sessions. Post-test was performed after a 4-week period. Pain, strength, and function were assessed before and after the intervention. Results: The results of the study showed that there was a significant difference in pain reduction and muscle strength improvement in the experimental group, and a significant difference was also found between the experimental group and the control group in terms of functional evaluation. Conclusions: The combination of exercise therapy and electrical muscle stimulation therapy resulted in greater improvements in pain, strength, and function assessment, contributing to improved overall function.

• Child Health Nursing Research
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• v.30 no.3
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• pp.187-198
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• 2024

Purpose: This study aimed to implement a child abuse prevention program and evaluate its effectiveness based on the Nursing Model of Resilience and Coping Skills Training Model for unmarried mothers during pregnancy and puerperium. Methods: This study had a prospective single-case, AB design with four repeated self-questionnaire measures and three observational measures. Seven unmarried mothers were provided with 10 sessions child abuse prevention program through individual visits from 32 to 34 weeks of pregnancy to six weeks after childbirth. The questionnaire was composed related to resilience, maternal stress, maternal attitude, parent-child interaction, child abuse potential. The observation was measured by video recording (total 16 times) the interaction of parent-child during feeding and analyzing it by three experts. Data were analyzed by Wilcoxon signed-rank test and Friedman's test. Results: Maternal attitude and parent-child interaction were statistically significantly improved after intervention compared to before intervention. However, maternal stress decreased after intervention compared to before intervention, but it was not statistically significant. Additionally, resilience and child abuse potential were not statistically significant. This program is partially effective in preventing child abuse by promoting parenting attitudes and parent-child interactions. Conclusion: This study focused on individual resilience and applied systematic intervention as coping skills training to prevent child abuse. This study is meaningful in that interventions were conducted through individual visits to unmarried mothers at high risk of child abuse, and the program was applied, including pregnancy and postpartum periods, to prevent child abuse early.

• Journal of the Korean GEO-environmental Society
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• v.16 no.2
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• pp.45-52
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• 2015

To minimize the cost of maintenance, repair and over-design of track substructure, an accurate evaluation of strength and stiffness of the track substructure is necessary. In this study, a cone penetrometer with impact penetration rod (CPI) is developed for the evaluation of track substructure. For applicability test, the chamber and field tests were performed. As the experimental results of the CPI, dynamic cone penetration endex (DCPI), cone tip resistance ($q_c$), friction resistance ($f_s$) and friction ratio (Fr) were obtained. In the chamber test, the experimental results show reasonable values for the simulated track substructure. In the field test, the CPI clearly detects the interface between the ballast and the subgrade. Also, discontinuous layers are detected in the subgrade. It is expected that the developed CPI may be an effective tool for the evaluation of track substructure by evaluating the ballast layer by dynamic penetration and the subgrade by static penetration of the inner rod.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.639-646
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• 2000

It is important to estimate the mechanical properties of clay since it is directly related to the design and the construction of geotechnical structures. Site exploration, which is composed of boring, sampling, in-situ, or laboratory tests, is preformed to estimate the mechanical properties. However, mechanical properties of clay measured from laboratory test may be different from in-situ properties due to disturbances occurred during sampling, transportation, storage, and trimming. In this study, the degree of disturbance according to sampling method was estimated with the test results of CK/sub o/U triaxial compression test on Yangsan clay. The soil samples were obtained by three types of sampling method, j.e., 76mm-tube sampler, 76mm-piston sampler, and block sampler. In order to evaluate the quality of samples, volumetric strain, undrained shear strength, secant Young's modulus, and pore pressure coefficient at peak measured from each sample were compared with one another. From the test results, it was observed that mechanical properties of the block and piston samples were more reliable than those of tube samples. But it was observed that the water content of piston was similar to that of tube samples at given depths while the water content of block samples was 14.3∼15.8% smaller than that of piston and tube samples. In addition to the evaluation of the quality of samples, relationship between c/sub u// σ/sub vc/'and OCR was established from the results of the CK/sub o/U triaxial compression tests, which were carried out using SHANSEP method. And also undrained shear strength was analyzed using the in-situ test data such as Cone Penetration Test(CPT), Dilatometer Test(DMT), and Field Vane Test(FVT) and was compared with that evaluated from CK/sub o/U triaxial compression test.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.4 s.50
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• pp.1-13
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• 2006

Soil and rock dynamic properties such as shear wave velocity $(V_s)$, compressional wave velocity $(V_p)$ and corresponding Poisson's ratio (v) are very important geotechnical parameters in predicting deformational behavior of structures as well as practicing seismic design and performance evaluation. In an effort to measure the parameter efficiently and accurately, various bore-hole seismic testing techniques have been, thus, developed and used during past several decades. In this study, cross-hole seismic testing technique which is known as the most reliable seismic method was adopted for obtaining geotechnical dynamic properties. To perform successfully the cross-hole test for rock as well as soil layers regardless of the ground water level, spring-loaded source which impact laterally a subsurface ground in vertical bore-hole was developed and applied at three study areas, which contain four sites composed of two existing port sites and two new LNG storage facility sites. The geotechnical dynamic properties such as $V_s,\;V_p$ and v with depth from the soil surface to the engineering and seismic bedrock were efficiently determined from the laterally impacted cross-hole seismic tests at study sites, and were provided as the fundamental parameters for the seismic performance evaluation of the existing ports and the seismic design of the LNG storage facilities.

• Journal of the Korean Geosynthetics Society
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• v.11 no.3
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• pp.43-51
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• 2012

This paper describes the stability evaluation of reinforced earth wall using geosynthetic strip based on field test. The wall facing, which is applied in field, is able to present excellent scenery, and the reinforcement has improvement effect of pullout resistance based on rounded band anchor. The measurement is conducted according to construction elapsed time of structure for earth pressure, horizontal displacement of wall facing and reinforcement strain in field test. The evaluation results show that the measured earth pressure is less than theoretical earth pressure due to dispersion effect of earth pressure by geosynthetic strip. The horizontal displacement of wall facing is also satisfied a empirical criteria. The measured strain of reinforcement had nearly no effect on stability of the reinforced earth wall. Therefore, the geosynthetic strip with rounded band anchor can be applied in the reinforced earth wall, and the reinforced earth wall with geosynthetic strip can be commonly used in field because it has a structural stability.