• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.7-19
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• 2002

This paper presents the results of an investigation on the effect of foundation stiffness on the performance of soil-reinforced segmental retaining walls (SRWalls). Laboratory model tests were performed using a reduced-scale physical model to capture the fundamentals of the manner in which the foundation stiffness affects the behavior of SRWalls. A series of finite-element analyses were additionally performed on a prototype wall in order to supplement the findings from the model tests and to examine full-scale behavior of SRWalls encountered in the field. The results of the present investigation indicate that lateral wall displacements significantly increase with the decrease of the foundation stiffness. Also revealed is that the increase in wall displacements is likely to be caused by the rigid body movement of the reinforced soil mass with negligible internal deformation within the reinforced soil mass. The findings from this study support the current design approaches, in which the problem concerning the foundation condition are treated in the frame work of the external stability rather than the internal stability. The implications of the findings from this study to current design approaches are discussed in detail.

• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.80-85
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• 2016

The carbon dioxide adsorption behavior of silica with a large specific surface area and pore volume functionalized with aminosilane compounds via in-situ polymerization and functionalization method were investigated. The organosilanes include amino functional group capable of adsorbing carbon dioxide. Elemental analyzer, in situ FT-IR and thermogravimetric analyzer were used to characterize the sorbents and to determine their $CO_2$ adsorption behavior. Comparison of different aminosilane loading in the support revealed that polyaminosilane functionalization of 70% of the pore volume in the support was better in terms of the adsorption capacity and amine efficiency than that of 100% of the pore volume of the support. Furthermore, the sorbents showed a higher adsorption capacity at an adsorption temperature of $75^{\circ}C$ than at $30^{\circ}C$ due to the thermal expansion of synthesized polyaminosilanes inside the pore of silica. The N-[3-(trimethoxysilyl)propyl]ethylenediamine (2NS) sorbent with 70% of the pore volume functionalized showed the highest adsorption capacity of 9.2 wt% at $75^{\circ}C$.

• KIISE Transactions on Computing Practices
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• v.23 no.6
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• pp.343-349
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• 2017

Combat modeling and simulation (M&S) of large-scale computer generated forces (CGFs) enables the development of even the most sophisticated strategy of combat warfare and the efficient facilitation of a comprehensive simulation of the upcoming battle. The DEVS-POMDP framework is proposed where the DEVS framework describing the explicit behavior rules in military doctrines, and POMDP model describing the autonomous behavior of the CGFs are hierarchically combined to capture the complexity of realistic world combat modeling and simulation. However, it has previously been well documented that computing the optimal policy of a POMDP model is computationally demanding. In this paper, we show that not only can the performance of CGFs be improved by an efficient POMDP tree search algorithm but CGFs are also able to conveniently learn the behavior model of the enemy through case studies in the scenario of counterfire warfare and the scenario of a mechanized infantry brigade's offensive operations.

• Korean Journal of Health Education and Promotion
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• v.26 no.1
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• pp.63-80
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• 2009

Objectives: This study identified how personal characteristics, healthy behavior and social capital might influence on physical activity of adults. Methods: This study used data from the health survey of a city of Korea. We surveyed 1,000 adults sampled by stratified sampling methods from 67,889 households. Outcome variable was the stage of physical activity which was broken into 5 categories. Sociodemographic factors, healthy behavior, self-rated health status and social capital were used as control variables. Sociodemographic factors included age, sex, educational status, economic status measured by deprivation score, residential period within survey city. Social capital was measured by Integrated Questionnaire for the Measurement of Social Capital (SC-IQ). This study used chi-square test and ordered logistic regression models to examine the associations between independent variables and physical activity. Variables were added to the regression model in three groups using a hierarchical approach. Results: Physical activity was significantly more likely to become active if they have higher educational status, healthier behavior. Among the six dimensions of SC-IQ, only "groups and networks" that is structural dimensions of social capital and "trust and solidarity" that is cognitive dimensions of social capital were significantly related to physical activity of adults. We found that a person having higher density of membership and having larger size of networks showed the high possibility of active physical activity. A person having high solidarity was significantly associated with physical activity, but general trust was inversely related to physical activity. Output dimensions of social capital did not show significant relationship to physical activity. Conclusion: We found that social capital is useful concept to explain health behaviors like physical activity. However we must consider social, cultural and political context of the study to evaluate the effect of social capital to health status and health determinants and to capture the exact meaning of relationship between them. We suggest further researches to refine the concept of social capital and to explain the relationship of social capital to diverse health determinants.

• Asia-Pacific Journal of Business
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• v.6 no.2
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• pp.19-33
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• 2015

Studies focusing on the constantly changing buying behavior and product preferences of a booming teen market are rare and this is particularly true in the Philippines. To address this gap in the literature, this study focused on the supermarket brands of cologne preferred by teens in the Philippines such as Lewis & Pearl (L&P), Johnson's Baby Cologne, Juicy, Bench, Ellips, Fiona, Bambini and Baby Flo which are manufactured by various competing companies. Essentially, this study presented and described the profile and buying behavior of cologne users and non-cologne users and determined whether preferential differences existed between these brands. The respondents consisted of 473 teens all over the Philippines stratified in terms of general location via the three major groups of islands in the Philippines: Luzon, Visayas and Mindanao. Respondents came from selected schools in Quezon City in Metro Manila, Sariaya in Quezon Province, Cebu City, and Digos City to represent the Greater Metro Manila Area, Luzon, Visayas and Mindanao, respectively. Findings showed that almost all of the respondents used cologne at varying degrees. In general, teens use several scents and brands of cologne and continually shift from one scent/brand to another scent/brand. This made it difficult for any company to capture loyal consumers. The most popular brands used by teenagers were Bench (61.7%), Lewis and Pearl (59%), Juicy (42%), Afficionado (32%), Fiona (19.3%), Penshoppe (18%), Bambini (12.6%), Ellips (11.3%) and Zen Zest (7.5%). Fragrance or scent is the top priority of teenagers in choosing a cologne brand, followed by brand name, affordability, bottle design and endorser. The spray bottle type of colognes is preferred even if cologne spray bottles are priced higher than the splash cologne bottle type. Managerial implications of these findings for market players, marketing scholars and prospective investors are presented.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.4
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• pp.363-370
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• 2009

We simulated large deformation and inelastic behavior of API-X80 steel linepipes using nonlinear finite element method. Gurson-Tvergaard-Needleman(GTN) model is employed for the development of the constitutive model of the steel. The GTN model is implemented in the form of the user-supplied material subroutine(UMAT) for the commercial software of ABAQUS. To calibrate the model parameters, we simulated the behavior of the uniaxial tension test using ABAQUS equipped with the developed GTN model. Using the set of the model parameters, we were able to capture the characteristics of the plastic buckling of API-X80 steel linepipes.

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.148-155
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• 2018

To get a better understanding of the effect of physicochemical properties and microstructure on $SO_2$ absorption behavior of DESs with different molar ratios of EmimCl and EG (from 2:1 to 1:2), densities (${\rho}$), viscosities (${\eta}$), speeds of sound (u), refractive indices ($n_D$), and thermal decomposition temperatures ($T_d$) of EmimCl-EG DESs were measured and used to obtain the other derived properties, such as thermal expansion coefficient (${\alpha}_p$) and activation energy for viscous flow ($E_{\eta}$). Moreover, FT-IR spectra and in situ variable-temperature NMR spectroscopy were employed to study the microstructures of DESs. Based on physicochemical and spectroscopic properties, the influence of the concentrations of EmimCl on the interactions in DESs was explored to be associated with their $SO_2$ absorption behavior. The results show that the interactions between $Emim^+$ and $Cl^-$ of EmimCl is gradually weakening with increasing the concentration of EG in DESs by forming of hydrogen bond interaction of $O-H{\cdots}Cl^-$, resulting in a decrease of ${\rho}$, ${\eta}$, u, $n_D$, and $T_d$ of DESs, and hindering the charge-transfer interaction of $SO_2$ with $Cl^-$ and deceasing $SO_2$ capture capacity. Moreover, the $SO_2$ absorption capacity of DESs is proportional to their ${\rho}$ and $E_{\eta}$, respectively.

• Journal of Navigation and Port Research
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• v.44 no.6
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• pp.469-476
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• 2020

Modeling and Simulation (M&S) systems which deal with situational complexity often require human involvement due to the high-level decision-making that is necessary for ship movement, navigation, control center management, shipping company logistics, meteorological system information, and maritime transportation GIS. In order to properly simulate maritime traffic, it is necessary to accurately model the human decision-making process of the ship officer, including aspects of the ship officer's behavioral tendencies, personal navigation experience, and pattern of voyage errors, as this is the most accurate way in which to reproduce and predict realistic maritime traffic conditions. In this paper, which looks at agent-based maritime traffic simulation, we created a basic survey in order to conduct behavior analysis on ship operators' collision avoidance strategies. Using the information gathered throughout the survey, we developed an agent-based navigational behavior model which attempts to capture the behavioral patterns of a ship officer during an instance of ship collision. These results could be used in the future in further developments for more advanced maritime traffic simulation.

• Journal of the Korean Geotechnical Society
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• v.22 no.4
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• pp.73-83
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• 2006

Seepage analysis through unsaturated zone based on the theory of unsaturated flow is commonly performed to evaluate dam safety. However, the concepts of unsaturated soil behavior have not been transferred into the hands of practicing geotechnical engineers since the problems involving unsaturated soils often have the appearances of being extremely complex. There is variability and uncertainty associated with the unsaturated hydraulic properties that in turn will lead to variability in predicting unsaturated soil behavior such as seepage rate and the pore water pressure distribution. In this paper, measurements of the soil-water characteristic curve and saturated hydraulic conductivity for the core material of dam were conducted. Then, finite element stochastic analysis was used to capture the effect of unsaturated hydraulic properties on the seepage behavior of dam. It is observed that the amount of seepage increases, as the values of unsaturated soil parameters a and n increase. The values of m and p showed opposite trend.

• Korea journal of population studies
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• v.30 no.2
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• pp.97-116
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• 2007

As the fertility level in Korea continues to drop with detrimental implications for the society, it has regained much attention of academics and policy makers. This study, building on the previous research on fertility behavior, attempts to explore the plan of young married women to have an additional child. While such plan is not always put into practice, it is still closely related to fertility behavior. In addition, it can provide useful clues to understanding behavior in the future. Utilizing a recent nationwide survey on marriage and fertility, the study analyzes the plan of further birth among young married women according to the number of their children. The results show that the plan for first child is quite universal as no difference is found by their socioeconomic and demographic characteristics. However, having plan for second child differs by the work status of husbands, presence of mother of young married women, and the sex of first child. The effects of first two factors suggest that young married women take into consideration stability of home economics and availability of care sharing. As for the plan for the child, the present and ideal sex composition of children appear most important. The results indicate that the mechanism of fertility progression differs by the current number of children. Thus, consideration of such differential would help us deepen our understanding of fertility behaviors and need to reflect in the study. The study also argues that comprehensive and systematic qualitative research should be accompanied by to capture complexity of fertility decision making process.