• Earthquakes and Structures
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• v.16 no.1
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• pp.119-127
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• 2019

When a structural wall is subjected to multi-directional ground motion, torsion-induced cracks degrade the stiffness of the wall. The effect of torsion should not be neglected. As a main lateral load resisting member, reinforced concrete (RC) structural wall has been widely studied under the combined action of bending and shear. Unfortunately, its seismic behavior under a combined action of torsion, bending and shear is rarely studied. In this study, torsional performances of the RC structural walls under the combined action is assessed from a comprehensive parametrical study. Finite element (FE) models are built and calibrated by comparing with the available experimental data. The study is then carried out to find out the critical design parameter affecting the torsional stiffness of RC structural walls, including the axial load ratio, aspect ratio, leg-thickness ratio, eccentricity of lateral force, longitudinal reinforcement ratio and transverse reinforcement ratio. Besides, to facilitate the application in practice, an empirical equation is developed to estimate the torsional stiffness of RC rectangular structural walls conveniently, which is found to agree well with the numerical results of the developed FE models.

• Steel and Composite Structures
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• v.44 no.2
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• pp.225-240
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• 2022

Local responses of steel plate-concrete composite (SC) walls under impact loads are typically evaluated using design equations available in the AISC N690s1-15. These equations enable design of impact-resistant SC walls, but some essential parts such as the effects of wall size and shear reinforcement ratio have not been addressed. Also, since they were developed for design basis events, improved equations are required for accurate prediction of the impact behaviors of SC walls for beyond design basis impact evaluation. This paper presents a numerical study to construct a robust numerical model of SC walls subjected to impact loads to reasonably predict the SC-wall impact behavior, to evaluate the findings observed from the impact tests including the effects of the key design parameters, and to assess the actual responses of full-scale SC walls. The numerical calculations are validated using intermediate-scale impact tests performed previously. The influences of the fracture energy of concrete and the conservative aspects of the current design equations are discussed carefully. Recommendations are made for design practice.

• Journal of the Korean Geotechnical Society
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• v.28 no.11
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• pp.69-78
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• 2012

Conventional numerical analysis for rainfall-induced slope stability has been estimated by separating seepage and stress-strain behavior, respectively. Many researchers' models from commercial softwares and literatures define that partially saturated permeability is the only function of degree of saturation (or matrix suction) and then they do not consider hydraulic-mechanical characteristics for the analysis. However, in practice, the water flow processes in a deformable soil are influenced by soil skeleton movement and the pore water pressure changed due to seepage will lead to changes in stress and to deformation of a soil. The relationship between seepage and soil behavior causes a change of partially saturated permeability as well as saturated permeability with the lapse of time. Instability of partially saturated soil slopes due to infiltration would be analyzed from reduction of negative pore water pressure calculating the process of water flow based on predicted partially saturated permeability. Therefore, partially saturated permeability should be defined by the function of degree of saturation (or matric suction) and porosity. The paper presents the comparison between staggered and monolithic coupled analysis regarding seepage and stress deformation problems. As a result, the decrease in matric suction on soil slope from monolithic analysis is slower than that from staggered analysis.

• Korean Journal of Health Education and Promotion
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• v.21 no.4
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• pp.35-49
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• 2004

The purpose of this study was to analyze variables associated with smoking and selected health behaviors. This study targeted adult men and women over 20 of age. The sample population was drawn from the national sample, and the samples were chosen from the telephone book. A total of 1,500 cases were collected through a telephone based interview survey. As a tool for this study, a structured questionnaire was developed. the variables included self-perceived health status, and selected 7 health behaviors; smoking behavior, physical activities, eating habit, weight control, alcohol consumption, stress management, and cancer exam. The healthy life practice actions of Trans-theoretical model have been classified into five stages. Smokers were more likely than non-smokers to positive attitudes toward smoking and the impact of smoking in this study. This means that smokers's awareness toward the impact of smoking is very week. Smoking behavior was significantly related to other health related behaviors based on the correlation analysis. However, gender, engaging in regular physical activities, moderate consumption of alcoholic beverages, and receiving a cancer examination were the variables that can explain and predict a person's stages of adopting a non-smoking behavior. Self perceived health status was closely related to other health behaviors. Gender, age, and monthly household income were important demographic variables that have significant relationship with the self-perceived health status. Among the health behaviors, regular physical activities and weight control were significant predictable variables. Similar results have been found in the National health and Nutrition examination survey in Korea. As a result of this study, it was found that among the selected health behaviors, engaging in physical activity was an important variable to increase positive sense of health and non-smoking behaviors. Educational and policy level input is needed to increase awareness and provide chances to participate in fitness activities. To those who maintain exercise, the environmental support and diffusion of knowledge information and education data should be strengthened. To change attitudes toward smoking, more in-dept awareness campaign and education should be provided according to people's different behavioral status. In addition, not only diffusing health education data and delivering knowledge information through related programs, but also environmental support system that helps an individual maintain his/her action is required. Such a support system means settlement of the health enhancement base of school, workplace and community should be carried out, and the policy level support and regular programs should be provided and spread to the unit of community.

• Steel and Composite Structures
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• v.26 no.2
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• pp.197-211
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• 2018

The study presents the earthquake performance of the Bosphorus Bridge under multi-point earthquake excitation considering the spatially varying site-specific earthquake motions. The elaborate FE model of the bridge is firstly established depending on the new considerations of the used FEM software specifications, such as cable-sag effect, rigid link and gap elements. The modal analysis showed that singular modes of the deck and the tower were relatively effective in the dynamic behavior of the bridge due to higher total mass participation mass ratio of 80%. The parameters and requirements to be considered in simulation process are determined to generate the spatially varying site-specific ground motions. Total number of twelve simulated ground motions are defined for the multi-support earthquake analysis (Mp-sup). In order to easily implement multi-point earthquake excitation to the bridge, the practice-oriented procedure is summarized. The results demonstrated that the Mp-sup led to high increase in sectional forces of the critical components of the bridge, especially tower base section and tensile force of the main and back stay cables. A close relationship between the dynamic response and the behavior of the bridge under the Mp-sup was also obtained. Consequently, the outcomes from this study underscored the importance of the utilization of the multi-point earthquake analysis and the necessity of considering specifically generated earthquake motions for suspension bridges.

• Nutrition Research and Practice
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• v.17 no.6
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• pp.1155-1169
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• 2023

BACKGROUND/OBJECTIVES: Unhealthy food choices among young adults are common globally, and the incidence of chronic diseases, such as obesity, is rising. Food literacy (FL) is important for improving and maintaining individual health in a rapidly changing food environment and can form the basis for following a sustainable diet. Therefore, it is essential to improve FL among young adults, particularly college students, who are in the formative years of their lifelong food habits. This study examined the facilitators and barriers of FL and related dietary behavior among college students in South Korea. SUBJECTS/METHODS: This study recruited 25 college students with different residence types using convenience and snowball sampling. In-person, telephone, and video interviews were conducted from March to November 2021. The interview data were analyzed using framework analysis based on the socio-ecological model. RESULTS: At the individual level, prior good experiences with food were the most frequently mentioned facilitator. In contrast, the major barriers were a lack of knowledge, financial hardship, irregular schedules, and academic stress. At the interpersonal level, the influences of family and peers, such as early exposure to healthy eating habits and opportunities to have easy accessibility to farms and farming, are major facilitators, but the lack of a sense of community was the major barrier. At the environmental level, the major barriers were unfavorable food environments at home and in neighborhoods, such as the absence of kitchens in housing and large packaging of produce at markets. CONCLUSIONS: Many factors affected the students' FL and related healthy eating practices. These findings suggest that a campus-based FL program should be developed by reflecting on these facilitators and barriers.

• Journal of Nutrition and Health
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• v.48 no.4
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• pp.335-343
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• 2015

Purpose: The aim of this study was to evaluate the food behavior and nutritional status of elementary school students in the Jeju area using Nutrition Quotient (NQ). Methods: The subjects were 440 students (235 boys and 205 girls) in the fifth and sixth grade at four elementary schools located in Jeju. Demographic, lifestyle, and environmental information was collected using a self-reported questionnaire. The food behavior checklist for children's Nutrition Quotient (NQ), consisting of 19 items, and nutrition education related information were also obtained. Results: The mean score of the children's NQ was poor, reaching 60.3 points. The percentage distribution of NQ grade was 19.8% (lowest), 18.6% (low), 45.0% (medium), 10.7% (high), and 5.9% (highest) and the factor scores for balance, diversity, abstinence, regularity, and practice were 56.6, 68.4, 71.3, 57.4, and 54.8 points, respectively. Compared with the NQ cut-off points for defining malnutrition (balance; 57, diversity; 87, abstinence; 66, regularity; 69, and practice; 67 point), average score of abstinence factor was only above the cut-off point and scores of the other factors were below the cut-off point. Subjects with higher NQ scores tended to have higher levels of exercise activity (p < 0.001), frequency of family meals (p < 0.01), and father's educational levels (p < 0.01) compared to those with lower NQ score. NQ score showed positive association with nutrition education experience and practice (p < 0.001). Conclusion: NQ score of elementary school students residing in Jeju was lower than the national average. More opportunities should be provided for participation in nutrition education, which incorporates a range of program strategies, as well as communication and education activities.

• Journal of the Korean GEO-environmental Society
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• v.10 no.2
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• pp.69-76
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• 2009

In this study, design method for debris flow and drift wood dams used in Japan was evaluated to develop currently available design method practiced in Korea. In Japan, represented a similarity in the aspects of topography and the climate compared with Korea, casualties due to debris flow, landslide, and collapse of cliff as well as earthquake, have been reported every year. Especially, debris flow had often occurred during heavy rainy season rather than due to Typhoons or localized torrential thunderstorms. Since the characteristic of the debris flow reveals in the middle of water flow and soil behaviors, the behavior of debris flow associated with drift wood was not fully understood at this moment and therefore empirical design method to design debris flow dam is adopted in the practice and currently used in Japan. Based on the result of this study, modification of debris flow design method used in Korea are presented.

• Korean Journal of Environmental Agriculture
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• v.37 no.1
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• pp.41-48
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• 2018

BACKGROUND: This study was performed to calculate the biological half-lives and regression coefficient of bistrifluron and cyenopyrafen dissipation in peach and to estimate the Pre-Harvest Residue Limits (PHRLs). METHODS AND RESULTS: The bistrifluron and cyenopyrafen were prepared on the basis of good agricultural practice for peach and treated with a single application. Peaches were harvested at 0, 1, 3, 5, 7, 10 and 14 days after application, prepared for analysis, and analyzed by HPLC-DAD. The limits of quantitation (LOQ) of bistifluron and cyenopyrafen were 0.02 mg/kg and 0.04 mg/kg, respectively. The recoveries of bistrifluron and cyenopyrafen were 99.5~108.7% and 88.4~98.9% at two different concentration levels. The biological half-lives of field I (Sejong) and field II (Pyeongtaek) were 6.1 and 7.0 days for bistifluron, and 6.3 and 7.0 days for cyenopyrafen, respectively. The 95% confidence intervals of dissipation rate constants of bistrifluron in peach were 0.0805~0.1457 and 0.0577~0.1417 for field I and field II, respectively, and those of cyenopyrafen were 0.0911~0.1278 and 0.0576~0.1417, respectively. CONCLUSION: Residue dissipation of bistrifluron and cyenopyrafen in peach were similar to that of correction to sample weight difference during the harvest periods. This study suggests that residue dissipation rate would be helpful to set the PHRLs that protect public health.

• Journal of Korean Academy of Nursing Administration
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• v.8 no.3
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• pp.361-372
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• 2002

Purpose : The purpose of study was to identify to analysis of core nursing interventions performed by Operating Room nurses. Method : The subjects of the study were arbitrarily selected nurses(n=104) working in Operating Room. The period for data collection was 15 days from July, 15, 2002 to July, 30. 2002. The instrument for study was 486 Nursing Interventions Classification developed by McClosky & Bulechek(2000) and was translated into Korean. In 486 nursing interventions, 57 nursing interventions were selected by more than half of 47 professional nurses group of Operating Room. 57 nursing interventions were used as a secondary questionnaire. In the secondary questionnaire, labels and definitions of all 57 interventions were listed. The collected data were self reported by Operating Room nurses. The data were analysed with SPSS program. Result : In 57 nursing interventions, the 'Behavior' domain was the most frequently used. Core interventions of Operating Room were performed several times a day by more than 50% of Operating Room nurses. Core interventions of Operating Room were 16 Core interventions, 7 classes, 5 domains. In the core interventions, the 'Physiological:Complex' domain was the most frequently used. Core interventions of Operating Room were Surgical Preperation, Infection Control:Intraoperative, Surgical Precautions, Fall Prevention, Documentation, Surgical Assistance, Environmental Management:Safety, Skin Surveillance, Physical Restraint, Pressure Ulcer Prevention, Environmental Management:Comfort, Infection Protection, Presence, Emotional Support, Specimen Management, Shift Report. Conclusion : Core interventions of Operating Room have implications for nursing care practice, nursing education, nursing research, and nursing information system in Operating Room.