• Journal of Korean Society of Steel Construction
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• v.20 no.4
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• pp.505-517
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• 2008

A numerical analysis method was studied to predict the nonlinear behavior of slender double skin composite walls. For convenience in numerical analysis, the model for the double skin composite wall was developed as a macroscopic model that can predict nonlinear behavior with relatively simplified models. For the wall showing flexure-dominant behavior, a multiple layer model was used. Each layer was modeled with composite elements of concrete and steel plate. An X-type truss model was used for coupling beams showing shear-dominant behavior. To describe the cyclic behavior of concrete and steel elements, simplified cyclic models for the materials were proposed. The proposed analysis model was applied to isolated walls and coupled walls with rectangular or T-shaped cross-sections. The analytical results were compared with existing test results.

• Journal of Mechanical Science and Technology
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• v.17 no.6
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• pp.796-804
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• 2003

The use of fracture mechanics has traditionally concentrated on crack growth under an opening mechanism. However, many service failures occur from cracks subjected to mixed-mode loading. Hence, it is necessary to evaluate the fatigue behavior under mixed-mode loading. Under mixed-mode loading, not only the fatigue crack propagation rate is of importance, but also the crack propagation direction. In modified range 0.3$\leq$a/W$\leq$0.5, the stress intensity factors (SIFs) of mode I and mode II for the compact tension shear (CTS) specimen were calculated by using elastic finite element analysis. The propagation behavior of the fatigue cracks of cold rolled stainless steels (STS304) under mixed-mode conditions was evaluated by using K$\_$I/ and $_{4}$ (SIFs of mode I and mode II). The maximum tangential stress (MTS) criterion and stress intensity factor were applied to predict the crack propagation direction and the propagation behavior of fatigue cracks.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.6
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• pp.852-859
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• 2000

The emission in the exhaust gas from diesel engine is effected by the fuel spray characteristics. The spray of D.I. diesel engine impinges on a piston cavity and a cylinder wall. It is very important to know exactly the distribution and behavior of the spray inside cylinder. The objective of this study is to develop more accurate evaporation model. The EPISO code was used to analyze the flow characteristics in the engine. The Wakil model and the Faeth model are applied to the EPISO code to analyze the behavior of impinging spray. And also experimental and numerical analysis were carried out. The spray behavior characteristics were investigated by changing injection pressure, ambient pressure and temperature. The behavior of impinging spray was strongly effected by the change of ambient pressure and temperature. The effects of evaporation and rebounding droplet should be considered.

• Journal of the Korean Applied Science and Technology
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• v.39 no.4
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• pp.499-506
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• 2022

This study is a descriptive research study that attempted to investigate the effects of growth mindset and self-leadership on career preparation behavior of senior nursing students. The data collection period is from November 1 to 30, 2021, and the subject of the study is 173 nursing students from three universities located in G city and J province. For data analysis, t-test, ANOVA, descriptive analysis, Pearson's correlation, and controlled regression analysis were performed using the SPSS 26.0 program. As a result of the study, self-leadership(𝛽=.435, p<.001) and growth mindset(𝛽=.193, p=.005) had a positive effect on career preparation behavior and explained career preparation behavior by 32.0%. Therefore, it suggests that a practical strategy for cultivating self-leadership and growth mindset is necessary to promote career preparation behavior of senior nursing students.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.13 no.2
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• pp.257-270
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• 2000

The objective of this study is to develop a damage model based on damage mechanics that can be used to analyze the mechanical behavior of structures with defects and the global behavior of damaged structures. A modified second order damage tensor that can be applied to finite element analysis is used to reflect the effect of damage. The damage stress computed from the effective stress is considered as an additional loading term acting on nodes and can represent the effect of crack surface. The accuracy of the proposed algorithm is verified by comparing the analysis results with the experimental data from other studies and the analysis results based on transverse isotropic theory. The developed damage model is applied to the analyses of structures with cracks under linear elastic condition. The comparisons confirmed that the quantitative analysis of the structural behavior due to crack orientation and multiple sets of cracks is possible. Also, the damage caused by rock excavation and fault zone is analyzed. The results also showed that the developed model can effectively analyze the global behavior of damaged structures.

• Journal of Distribution Science
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• v.17 no.8
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• pp.57-66
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• 2019

Purpose - The purpose of this study is to elucidate the perception differences between CEOs and employees, and to derive a plan for improving performance by using theory of planned behavior (TPB) to enhance the competitiveness of SMEs exposed to various difficulties until recently. Research design, data and methodology - A total of 238 valid questionnaires were collected for CEOs and members of SMEs. In order to clarify the difference of perception, independent sample t-test and multi-group analysis using AMOS were conducted. Simple regression analysis and structural equation were used to confirm whether the theory of planned behavior was applied at the level of SME. Results - The CEO group is more aware of company's ethical responsibility activities and organizational support than the group of employees, and collectivism contributes more to organizational development than individualism tendency. Also, the theory of planned behavior is applied to the SME level as well. Conclusion - This study suggest that CEOs need to accept the pluralism of their members for the development of SMEs. In addition, it is necessary to form a consensus on ethical responsibility activities that corporations are performing by supporting diverse strategies and members' participation in management decision-making.

• International Journal of Concrete Structures and Materials
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• v.10 no.1
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• pp.99-112
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• 2016

During earthquake, reinforced concrete walls show complicated post-yield behavior varying with shear span-to-depth ratio, re-bar detail, and loading condition. In the present study, a macro-model for the nonlinear analysis of multi-story wall structures was developed. To conveniently describe the coupled flexure-compression and shear responses, a reinforced concrete wall was idealized with longitudinal and diagonal uniaxial elements. Simplified cyclic material models were used to describe the cyclic behavior of concrete and re-bars. For verification, the proposed method was applied to various existing test specimens of isolated and coupled walls. The results showed that the predictions agreed well with the test results including the load-carrying capacity, deformation capacity, and failure mode. Further the proposed model was applied to an existing wall structure tested on a shaking table. Three-dimensional nonlinear time history analyses using the proposed model were performed for the test specimen. The time history responses of the proposed method agreed with the test results including the lateral displacements and base shear.

• Journal of Industrial Technology
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• v.33 no.A
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• pp.73-80
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• 2013

This paper is results of numerical analysis on the behavior of colluvium slope with combinations of soil nails and earth anchors during excavation. In order to maintain the stability of the colluvium cut, being composed of gravel and boulder and thus local in stability being expected during slope cut, temporary reinforcing method of soil nailing with shotcrete might be used. Subsequent method of cast-in-place facing with earth anchors can be used to maintain cut slope stable permanently. For the cut slope where these methods had been applied, the numerical techniques were applied to their behaviors and investigate the stability of the slope. Limit equilibrium methods were used to confirm to maintain the slope stability during and after excavation and application of those reinforcing methods. Another numerical technique of FEM was also used to find the stress and strain as well as deformation distribution in reinforcing materials and slope ground during excavation.

• Journal of the Korean Society of Food Culture
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• v.23 no.3
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• pp.377-387
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• 2008

The objective of this study was to use cluster analysis to determine differences in eating-out behavior among grouped clusters of female consumers after each cluster was divided based on lifestyle patterns. The data were collected by interview survey from a biased sample of 1,300 females, ranging from ages 20 to 59, and living in residential districts of Seoul. Reliability analysis, factor analysis, cluster analysis, cross-tabulation analysis, and analysis of variance (ANOVA) were applied to the data. Four lifestyle factors were extracted by lower-division and classified as follows: health condition, consuming, food, and housing lifestyles. Based on these four factors, the female consumers were grouped as three clusters: the consuming-individuality type, rational-pursuit type, and conservative-stability type. The eating-out behavior of each cluster was significantly different in terms of frequency of eating-out, eating-out expenditures, restaurant selection criteria, food preferences, and the purpose for eating-out. Since this study surveyed females from ages 20 to 59, age and demographics were the differential factors in determining the various lifestyle types. Thus, to target the consumers who form a target market, the food industry should consider market segmentation that combines demographic factors such as age, income, and marital status.

• Journal of the Korean Home Economics Association
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• v.42 no.9
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• pp.111-134
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• 2004

The purpose of this dissertation is firstly to examine the level of pro-environmental behavior of urban employed wives depending on their life style type and secondly to identify effective ways to promote their pro-environmental behavior. A structured questionnaire interview was conducted with 700 urban employed wives who lived in the Seoul Metropolitan area, and 566 of the responses were valid for analysis. For statistical analysis, this research reviewed the frequencies, percentage, mean, standard deviation(SD), Pearson's correlations, Cronbach's u, factor analysis, cluster analysis, ANOVA, $\chi$$^2$-test, Duncan's Multiple Range Test, and multiple regression using SPSS/PC WIN. The findings of analysis of the study are as follows: 1. Among life style types of employed wives, the order of ecological value was orientation type (37.3%), followed by economical value orientation type (25.8%), uninterested type (18.7%), and convenience-centric value orientation type (18.2%).Pro-environmental behavior scored relatively highly at 3.45 in average. 2. In the analysis of the relationship between life style and background variations, every variation except environmental knowledge was meaningful. 3. In the relationship between pro-environment behavior and background variations, every variation was meaningful except housing types, having helper or not, and environmental knowledge. 4. The recognition level of environmental pollution was important among the variations affecting pro-environmental behavior. 5. There was a difference in pro-environmental behaviors by the following life style types: ecological value orientation, economical value orientation, convenience centric orientation and uninterested. 6. For the relative contribution comparison of background variations (socio-economic variation and environmental variation) and life style variations to the pro-environmental behavior of urban empolyed wives, this research additionally applied each independent variable group. As a result, the explanation level drastically increased in the third step that analyzed the relationship with life style.