• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.90-92
• /
• 2017

Due to the popularity of social networks and the development of technology in mobile networking, the mobile social networks (MSNs) provide opportunities for the spread of information between mobile devices. As a result, understanding the information diffusion in the emerging MSNs is a critical issue. Many research studies have addressed diffusion minimization, which is a problem of how to find the proper initial k users who can effectively propagate as widely as possible in the minimum amount of time, similar to influence maximization. We address a study on association analysis among nodes in information diffusion and mobility pattern for mobile social networks. Experiments in our study were conducted in the Opportunistic Network Environment (ONE) simulator using GPS trace of mobile node, to show that the study results in MSNs. We also demonstrate that our experiments outperform other existing algorithms with various communication range and ratio of k influential nodes.

• Journal of Korea Society of Industrial Information Systems
• /
• v.29 no.1
• /
• pp.49-62
• /
• 2024

In this paper, a sustainable closed-loop supply chain (SCLSC) network model is proposed for domestic mobile phone industry. Economic, environmental and social factors are respectively considered for reinforcing the sustainability of the SCLSC network model. These three factors aim at minimizing total cost, minimizing total amount of CO₂ emission, and maximizing total social influence resulting from the establishment and operation of facilities at each stage of the SCLSC network model. Since they are used as each objective function in modeling, the SCLSC network model can be a multi-objective optimization problem. A mathematical formulation is used for representing the SCLSC network model and a hybrid meta-heuristic approach is proposed for efficiently solving it. In numerical experiment, the performance of the proposed hybrid meta-heuristic approach is compared with those of conventional meta-heuristic approaches using some scales of the SCLSC network model. Experimental results shows that the proposed hybrid meta-heuristic approach outperforms conventional meta-heuristic approaches.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.36 no.5
• /
• pp.927-936
• /
• 2016

This research aims to analyze the effect of different types of urban parks and their locational characteristics on the apartment price in the entire metropolitan area of Busan, Korea. Although an urban park is an environmental good that influences the surroundings in many ways, most of the previous studies have underestimated its impact on the value of the surrounding area. This research focuses on the economic value of urban parks by understanding their relationship with the value of the apartments in the surrounding area with its significance in their physical and objective characteristics. Furthermore, the research emphasizes the different typological characteristics of urban parks in the analysis. In summary of the result, the number of levels (stories) and units of the apartment complex, ranking of the contractor, age of a park and accessibility to sub-central are positively related to the price of apartment units. On the other hand, the total area of apartment complex, the age of apartments, the distance to the nearest park and accessibility to civic-central or regional district are negatively related to the price of apartment units. Having a plan for constructing a park is also positively related to the price. For the typological characters of a park, neighborhood park, small-sized park, and sports park are positively related to the price, while children's park is negatively related to the price of apartment units. Considering that the price increases as the distance to the nearest park decreases, people prefer to live near the benefits that urban parks provide. In order to maximize the value and benefits that parks provide, it is necessary to approach them creatively.

• Journal of Gifted/Talented Education
• /
• v.23 no.5
• /
• pp.671-695
• /
• 2013

This study provides an illustrative example of using the multivariate generalizability theory. Specifically, it investigates relative effects of each error source, and finds optimal measurement conditions for the number of items within each content domain that maximizes the reliability-like coefficients, such as a generalizability coefficient and an index of dependability. The method is based on teacher recommendation letters and self-introduction letters, using an analytic scoring method in the context of selection of mathematically gifted students by observation and nomination. This study analyzed data from the 2011 academic year in the science education institute for the gifted, which is attached to the university located in the Seoul metropolitan area. It should be noted that the optimal scoring structures of this study are not generalizable to other selection instruments. However, the methodology applied in this study can be utilized to find optimal measurement conditions for the number of raters, the number of content domains, and the number of items in other selection instruments self-developed by many institutions including: the education institutes for the gifted at provincial offices of education, gifted classes, and the science education institutes for the gifted attached to universities in general. In addition, the methodology will provide bases for making informed decisions in selection instruments of the gifted based on measurement traits.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.46 no.6
• /
• pp.41-48
• /
• 2018

The aim of this study is to provide foundational knowledge of how to enhance the user satisfaction of urban parks. The study seeks to identify essential factors that influence user satisfaction and to provide better design strategies for future park design as well as the reorganization of existing ones. To measure user satisfaction, this study used factor analysis to extract essential factors - facility conditions, landscape and scenery, safety, and kindness - by using data from a survey conducted by the city of Seoul in 2017. We then used a regression analysis to infer causal relationships between the independent variables and the dependent variables (user satisfaction). The results revealed that the most significantly and positively related variable to user satisfaction in urban parks was safety (${\beta}=0.276$, p<.000), followed by landscape and scenery (${\beta}=0.230$, p<.000), facility conditions (${\beta}=0.215$, p<.000), and kindness (${\beta}=0.208$, p<.000). The results indicate that, for future urban park designs, planners and designers should prioritize the issues of safety by adopting crime prevention through environmental design (CPTED). In addition, planners and designers of future park designs should heavily weigh the selection and provision of relevant facilities for the intended use as well as well-arranged and well-managed plants and trees. Based on the results of IPA analysis, the most urgent improvement elements appeared to be the factor of kindness; however, the impact of kindness influencing user satisfaction was less important than that of safety and landscape and scenery in the urban park design processes. This study demonstrates that to maximize the user satisfaction of the urban park design processes and to provide more valuable spaces for users, it is necessary to secure park safety and to create well-composed landscape and scenery. Future research should provide more detailed and specified urban park design strategies corresponding with the importance of the factors identified in this study.