• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1192-1207
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• 2014

Dynamic spectrum sharing is a key technology to improve spectrum utilization in wireless networks. The elastic spectrum management provides a new opportunity for licensed primary users and unlicensed secondary users to efficiently utilize the scarce wireless resource. In this paper, we present a game-theoretic framework for dynamic spectrum allocation where the primary users rent the unutilized spectrum to the secondary users for a monetary profit. In reality, due to the ON-OFF behavior of the primary user, the quantity of spectrum that can be opportunistically shared by the secondary users is limited. We model this situation with the renewal theory and formulate the spectrum pricing scheme with the Bertrand game, taking into account the scarcity of the spectrum. By the Nash-equilibrium pricing scheme, each player in the game continually converges to a strategy that maximizes its own profit. We also investigate the impact of several properties, including channel quality and spectrum substitutability. Based on the equilibrium analysis, we finally propose a decentralized algorithm that leads the primary users to the Nash-equilibrium, called DST. The stability of the proposed algorithm in terms of convergence to the Nash equilibrium is also studied.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.3
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• pp.560-576
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• 2023

Drawing on gamification affordance theory, this study examines the relationships among key affordances of avatar fashion styling, perceived enjoyment, and engagement behavior intentions-defined as the intention to share content on avatars in the metaverse platform-and the moderating role of metaverse familiarity. Based on survey data collected from 198 Korean ZEPETO users with avatar fashion styling experience, the hereby proposed research model was tested with structural equation modeling. The results demonstrated that self-expression and competition positively influenced perceived enjoyment, which subsequently affected customers' engagement behavior intention. Furthermore, metaverse familiarity as a moderating effect intensified the positive association between affordances and perceived enjoyment as well as between perceived enjoyment and engagement behavior intentions. The individual interaction effect of each affordance dimension on perceived enjoyment was different, with self-expression having a greater influence on enjoyment among the high-familiarity group and competition having a greater influence on enjoyment among the low-familiarity group. Considering that users with low metaverse familiarity might have higher needs for social interaction for adaptation, competition, being more socially triggering, might have affected these users more crucially.

• Journal of Korea Society of Digital Industry and Information Management
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• v.18 no.4
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• pp.85-96
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• 2022

Personalized recommendation technology is one of the most important technologies in electronic commerce environment. It helps users overcome information overload by suggesting information that match user's interests. In e-commerce environment, both mobile device users and smart device users have risen dramatically. It creates new challenges. Our method suggests product information that match user's device interests beyond only user's interests. We propose a device-centered personalized recommendation method. Our method uses both purchase and share behavior for user's devices interests. Moreover, it considers data type preference for each device. This paper presents a new recommendation method and algorithm. Then, an e-commerce scenario with a computer, a smartphone and an AI-speaker are described. The scenario shows our work is better than previous researches.

• Asia pacific journal of information systems
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• v.28 no.2
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• pp.133-153
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• 2018

This study investigates responses to privacy concerns by analyzing the psychological and behavioral characteristics related to the disposition toward invoices of courier service users. To this end, we develop a theoretical framework by combining stimulus response theory, communication privacy management theory, the theory of reasoned action, and the theory of planned behavior. Based on the theoretical framework, we analyze the relationships between social influence, privacy propensity, privacy control, privacy risk, privacy concern, invoice disposition intention, and invoice disposition behavior in the context of courier services. To test our hypotheses, we survey courier service users in the U.S. and Korea. Using a structural equation model, we test the relationships among these various factors for the courier service users of the two countries. Results have distinct implications for the psychological and behavioral characteristics concerning the disposal of courier invoices and enable understanding of the characteristics of courier service customers of the two countries.

• The Journal of Information Systems
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• v.29 no.1
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• pp.201-224
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• 2020

Purpose The study focuses on the physical activity behavior change effect of smart wristband, which is the most popular type of fitness tracker nowadays. The purpose of the research is to investigate how people's workout behavior may change after wearing a smart band and examine what kind of role persuasive design plays in behavior change. Design/Methodology/Approach This research employed an experimental study to examine whether the user's workout behaviors changed after using wristband from the "Behavior Wizard" perspective. A representative smart wristband from a major vendor was selected as the objects of experimental study. In the experiment, by comparing users' workout behavior before and after using the wristband, behavior changes of all the experiment participants were classified into one of the 15 behavior change types. Users perceived persuasive design characteristics were measured and group differences were tested among different behavior change groups. Findings This research found that nearly half of the participants changed their workout behavior while half retained their workout status or no exercise status. Half of the participants who did not do exercise in their spare time started walking in the experiment. Results also showed that participants who started working out perceived higher levels of persuasive design devised into the smart band than participants who preserved no exercise status, except for facilitation and reward strategies. Participants who retained workout and those who increased workout frequency perceived no difference in smart band persuasive design.

• Knowledge Management Research
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• v.10 no.2
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• pp.85-103
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• 2009

Web 2.0, characterized as openness, sharing, and participation, has enabled Internet users to easily generate a variety of contents, and to share them through Web 2.0 services. Knowledge search service (KSS) is positioning itself as one of typical Web 2.0 services. Yet, few studies have sharpened our understanding of users' knowledge sharing behavior in the KSS environment. In order to address this knowledge void, this paper attempts to explore antecedents of their usage behavior in the KSS environment. Typically, they utilize stored knowledge and share their knowledge simultaneously. Considering this characteristic, our study regards service usage intention and knowledge sharing intention as final dependent variables. This study advances a research model based on Bhattacherjee's expectation-confirmation model, which is expanded by incorporating trust belief. Because of the openness of KSS, trust belief is believed to play a critical role in forming users' service usage intention and knowledge sharing intention. Furthermore, this study examines the difference of the antecedents' effects in terms of users' gender. We collected data from 275 respondents who have experience in using KSS. PLS (partial least squares) was employed for the analysis of the data. Analysis results confirm the important role of user satisfaction and trust belief in the formation of users' service usage intention and knowledge sharing intention. More importantly, trust belief has a more salient effect on knowledge service usage intention than user satisfaction. This study also shows the moderating role of users' gender. Finally, this paper provides managerial guidance on strategic planning aimed at improving users' service usage intention and knowledge sharing intention in the KSS environment.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.4
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• pp.16-31
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• 2007

This study is aimed at classifying different types of parks in Gwang-Ju city and providing efficient Planning and guidelines to satisfy the needs of park users. The first stage of this study was accomplished by site surveys of neighborhood parks in Gwang-Ju where park types, locations, neighboring conditions, park layout, and other physical environments were surveyed for the specific status of parks. With those basic data, urban neighborhood park types were classified into different categories: 1) urban neighborhood parks; 2) riverside neighborhood parks; and 3) natural(mountain side) neighborhood parks. For the second stage of this study, behavior patterns and satisfaction were investigated to provide empirical data on the relationship between the physical environment and human behavior. The main findings of this study can be summarized as follows: 1. The highest level of satisfaction for the users of urban neighborhood parks in Gwang-Ju city is the accessibility of the parks which are small but located in neighborhoods, The users tend to visit the nearby parks regardless of size. 2. The users have relatively high levels of satisfaction for urban neighborhood parks which have a lot of green zones or park facilities. Therefore, the park planner should consider the natural environment in the park area and should reconsider the type of park in the planning process. 3. The different types of urban neighborhood parks in Gwang-Ju city do not affect the level of satisfaction and the motivation of park visits. However, the accessibility of the parks is the most important factors of users' satisfaction regardless of the type of the park. 4. The level of user satisfaction for all of the urban neighborhood parks in Gwang-Ju city indicates that the users have a relatively low level of satisfaction. Especially, 26.2% of the users have a high level of dissatisfaction. The new parks, which have recently been developed, have a higher level of satisfaction than the old parks which have a lack of facilities, insufficient maintenance, and poor management planning in the park. 5. As a result of factor analysis, all city neighborhood parks showed a similar tendency with urban type parks, but showed a tendency that was different from the other park types.

• Journal of Korean Academy of Nursing
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• v.51 no.3
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• pp.380-389
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• 2021

Purpose: This study aimed to understand the relationship between cigarette and electronic cigarette (e-cigarette) use and sleep health among Korean adolescents. Methods: Using the 14th Korea Youth Risk Behavior Survey, we included 52,928 adolescents who responded to sleep satisfaction and sleep duration. Participants were classified into four groups: non-users, cigarette-only users, e-cigarette-only users, and dual users of both products. To examine the associations between cigarette and e-cigarette use and sleep health, data were analyzed using complex samples cross tabulation and complex samples logistic regression. Results: Of the four groups, dual users reported the lowest level of sleep satisfaction and sleep duration; 57.0% and 86.9% of dual users were not satisfied with their sleep and have insufficient sleep duration, respectively. The proportion of students who were not satisfied with their sleep was higher among cigarette-only users compared to e-cigarette-only users (52.7% vs. 45.8%), but the two groups reported similar rates of insufficient sleep duration (84.2% vs. 84.3%). Compared to non-users, cigarette-only users, e-cigarette-only users, and dual users were more likely to not be satisfied with sleep (odds ratios [ORs] were 1.49, 1.36, and 1.75, respectively) and had significantly higher odds of experiencing insufficient sleep duration (ORs were 1.85, 2.06, and 2.34, respectively). Conclusion: E-cigarette-only use and dual use as well as cigarette-only use were associated with poor sleep health. Therefore, to improve adolescent sleep health, health professionals should provide sleep intervention strategies considering the association between smoking and sleep health.

• The KIPS Transactions:PartB
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• v.11B no.5
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• pp.597-602
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• 2004

In spite of recent increase in the use of avatar systems in Web and Virtual Reality, there has not been a service that allows users to control directly the avatar behaviors. In addition, the conventional behavior control languages required a lot of complicated information for controlling the behaviors, so that users had difficulty using them. To apply written languages to a different task domain, moreover, it was necessary to modify or rewrite the languages. In this paper, for the avatar behavior control more simply define, “Task-Level Behavior Description Language,” which allows description the avatar behaviors in each task domain and “Motion Representation Language,” which enables writing detailed data for motion control. The system, developed in this paper, “included an Interpreter,” which automatically creates the Motion Representation Language, allowing users to easily control the avatar behaviors simply with the Behavior Description Language. The system was also applied to cyber classes, and the Task-level Behavior Description Language was compared with conventional languages to see how it was more effective in behavior description.

• Journal of The Korea Institute of Healthcare Architecture
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• v.22 no.3
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• pp.35-44
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• 2016

Purpose: This study is focus on investigation of user's spontaneous behavior in the public space of ward where chronic patients are hospitalized. Methods: The notion and necessity of social healing environment is analyzed by literature review. User's location and behaviour are investigated for analyzing behavior by visiting the six wards. Results: The result 1) Stay is main behavior of users. 2) The frequency of stay is high in the place where are planned as the dayroom, the program room and the balcony. 3) In the corridor, the users are staying around court and single side corridor. And the users who are staying in the ward planned middle corridor and double corridor are spreaded all over the corridor. As the result of the analysis of correlation between frequency of user for stay and area of public space, 4) The area of the dayroom, the program room and the balcony is bigger, the frequency of users are higher. 5) There is no correlation between area of corridor and frequency of users. 6) When the density of user is highest in the place for stay, one person occupied $1.96m^2$. Implications: Hereafter the public space, which social healing environment is considered, is planned, this study could suggest the directions of architectural planning about area.