• Journal of dental hygiene science
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• v.22 no.3
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• pp.148-155
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• 2022

Background: The use of dental floss along with a toothbrush is a well-known oral hygiene product that effectively removes dental plaque and reduces the risk of dental caries and periodontal disease. Despite the fact that various types of floss are being used, flossing methods based on the thread type are being taught. In addition, personal preference according to the floss types has not been investigated. In this study, individual preferences according to the floss types were investigated by experiencing various types of dental floss to both floss users and non-users. In addition, the change in intention to use dental floss in the future after flossing experience of non-users was investigated. Methods: General public participated in the individual interview survey (n=419). Subjects responded to the questionnaire after using all of the thread type, Y-type, and C-type floss. All statistics were expressed frequencies and percentages for categorical variables, and the chi-squared test was used to determine the statistical significance of associations between the variables. Results: As a result of the analysis, the preference of C-type floss was highest in both floss users and non-users. The biggest reason for not using dental floss was not knowing the necessity of flossing (36.4%). In addition, both floss users and non-users responded that C-type floss was suitable for flossing in the anterior and posterior regions. The change in the positive future intention to use dental floss after flossing experience of non-users was statistically significantly associated with age. Conclusion: This result suggests that there is a need to provide education on how to use dental floss in various forms. Based on this, it will be possible to lead a change in individual's attitude for future oral health through active and continuous flossing experience.

• Journal of Mechanical Science and Technology
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• v.14 no.9
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• pp.956-967
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• 2000

In this paper, we explore the issues of force display in the cooperative virtual environment shared by multiple users distributed over the network with heterogeneous hardware platforms. The proposed method is to cope with the problem of small time delay and the difference of sampling rate in the distributed configuration. In the proposed approach the interaction forces of the participants are just treated as the independent sources of acceleration. Thus the action of a participant simply changes the acceleration of the virtual object and consequently the states of the virtual object will be updated. When the updated states are reported to all the participants, the information on the time of state changes is delivered, too. Employing the discrete state information updated by the other users, each user modifies his own virtual environment and pseudo-realtime simulation can be realized. Excluding the software interface and the communication technique, it is proposed the simulation method for the operation of respective users and the way of calculating the driving input to the display device. For experimental verification we construct a cooperative virtual environment shared by two remote users and outline the results of experiments.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.4
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• pp.377-382
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• 2010

For business purposes, it is important to identify diffusion power users, a group of users who have big influence on other users in diffusing content. In this paper, we use the independent cascade model for determining diffusion power users, and to do so, we need a method for calculating the assimilation probability between users. This paper proposes the concepts of user delivery power and a way to quantifying the value of this. User delivery power is used to compute the assimilation probability with user content power. We analyze the proposed method by comparing its performance with those of existing methods through experiments using a real blog network data.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.3
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• pp.1363-1376
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• 2020

An improved clustering scheme based on user group is proposed. Every two users are grouped among N-users in the allowed system according to their link gain from large to small. Each user group is numbered sequentially. Two user clusters are obtained according to the principle of maximizing link gain difference for the users in the first and last user groups. The remaining user groups are added to the two existing user clusters according to the parity of the group number. The clustering should be clustered again among the users in either user cluster if the throughput summation of a user cluster in NOMA is less than that of these users in orthogonal multiple access. The simulation results show that the proposed clustering scheme can increase the system throughput by about 8% compared with the hybrid clustering scheme when the number of users requiring service is 12.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.6
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• pp.1042-1062
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• 2010

Cooperative spectrum sensing (CSS) is an effective technology for alleviating the unreliability of local spectrum sensing due to fading/shadowing effects. Unlike most existing solutions, this paper considers the use of CSS technology in decentralized networks where a fusion center is not available. In such a decentralized network, some attackers may sneak into the ranks of cooperative users. On the basis of recent advances in bio-inspired consensus algorithms, an attack-proof, decentralized CSS scheme is proposed in which all secondary users can maintain cooperative sensing by exchanging information locally instead of requiring centralized control or data fusion. Users no longer need any prior knowledge of the network. To counter three potential categories of spectrum sensing data falsification (SSDF) attacks, some anti-attack strategies are applied to the iterative process of information exchange. This enables most authentic users to exclude potentially malicious users from their neighborhood. As represented by simulation results, the proposed scheme can generally ensure that most authentic users reach a consensus within the given number of iterations, and it also demonstrates much better robustness against different SSDF attacks than several existing schemes.

• Journal of Communications and Networks
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• v.15 no.3
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• pp.283-291
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• 2013

In this paper, we propose new multiuser detectors (MUDs) based on compressed sensing approaches for the large-scale multiple antenna systems equipped with dozens of low-power antennas. We consider the scenarios where the number of receiver antennas is smaller than the total number of users, but the number of active users is relatively small. This prior information motivates sparsity-embracing MUDs such as sparsity-embracing linear/nonlinear MUDs where the detection of active users and their symbol detection are employed. In addition, sparsity-embracing MUDs with maximum a posteriori probability criterion (MAP-MUDs) are presented. They jointly detect active users and their symbols by exploiting the probability of user activity, and it can be solved efficiently by introducing convex relaxing senses. Furthermore, it is shown that sparsity-embracing MUDs exploiting common users' activity across multiple symbols, i.e., frame-by-frame, can be considered to improve performance. Also, in multiple multiple-input and multiple-output networks with aggressive frequency reuse, we propose the interference cancellation strategy for the proposed sparsity-embracing MUDs. That first cancels out the interference induced by adjacent networks and then recovers the desired users' information by exploiting the low user activity. In simulation studies for binary phase shift keying modulation, numerical evidences establish the effectiveness of our proposed MUDs exploiting low user activity, as compared with the conventional MUD.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1311-1324
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• 2019

In the traditional cellular network communication, the cellular user and the base station exchange information through the uplink channel and downlink channel. Meanwhile, device-to-device (D2D) users access the cellular network by reusing the channel resources of the cellular users. However, when cellular user channel conditions are poor, not only D2D user cannot reuse its channel resources to access the network, but also cellular user's communication needs cannot be met. To solve this problem, we introduced a novelty D2D communication mechanism in the downlink, which D2D transmitter users as half-duplex (HD) relays to assist the downlink transmission of cellular users with reusing corresponding spectrum. The optimization goal of the system is to make the cellular users in the bad channel state meet the minimum transmission rate requirement and at the same time maximize the throughput of the D2D users. In addition, i for the purpose of improving the efficiency of relay transmission, we use two-antenna architecture of D2D relay to enable receive and transmit signals at the same time. Then we optimized power of base station and D2D relay separately with consideration of backhaul interference caused by two-antenna architectures. The simulation results show that the proposed HD relay strategyis superior to existing HD and full-duplex (FD) models in the aspects of system throughput and power efficiency.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.12
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• pp.6034-6056
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• 2018

This paper describes two user studies in remote collaboration between two users with a video conferencing system where a remote user can draw annotations on the live video of the local user's workspace. In these two studies, the local user had the control of the view when sharing the first-person view, but our interfaces provided instant control of the shared view to the remote users. The first study investigates methods for assisting drawing annotations. The auto-freeze method, a novel solution for drawing annotations, is compared to a prior solution (manual freeze method) and a baseline (non-freeze) condition. Results show that both local and remote users preferred the auto-freeze method, which is easy to use and allows users to quickly draw annotations. The manual-freeze method supported precise drawing, but was less preferred because of the need for manual input. The second study explores visual notification for better local user awareness. We propose two designs: the red-box and both-freeze notifications, and compare these to the baseline, no notification condition. Users preferred the less obtrusive red-box notification that improved awareness of when annotations were made by remote users, and had a significantly lower level of interruption compared to the both-freeze condition.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.8
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• pp.2720-2735
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• 2022

This study proposes an internet design framework for users to improve their positive emotions when they are in a negative mood. First, the literature review focuses on the definition of emotion, positive emotional design in internet experiences, and emotion regulation. Second, in order to construct an internet design framework that improves positive emotion, this paper adopts a qualitative analysis method to analyze 70 collected studies in the area of regulating emotion and stimulating positive emotions. Additionally, bibliometrics and statistics are conducted to summarize the framework and strategies. Third, two cases of internet design are presented: (a) Internet design that improves users' positive emotions is examined under the background of extreme rainstorm as an example; an applet service design is provided by case study; (b) in the context of COVID-19, we developed an Internet of things interactive design that improves users' positive emotions. Fourth, the internet design framework and the results of the case studies are analyzed and discussed. Finally, an internet design framework is proposed to improve users' positive emotions when they are in a negative mood, which includes the Detachment-empathy framework, External-protection framework, Ability-strengthen framework, Perspective-transformation framework, and Macro-cognitive framework. The framework can help designers to generate design ideas accurately and quickly when users are in a negative mood, to improve subjective well-being, and contribute to the development of internet experience design.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.7
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• pp.1868-1887
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• 2024

Recommendation systems research is a subfield of information retrieval, as these systems recommend appropriate items to users during their visits. Appropriate recommendation results will help users save time searching while increasing productivity at work, travel, or shopping. The problem becomes more difficult when the items are geographical locations on the ground, as they are associated with a wealth of contextual information, such as geographical location, opening time, and sequence of related locations. Furthermore, on social networking platforms that allow users to check in or express interest when visiting a specific location, their friends receive this signal by spreading the word on that online social network. Consideration should be given to relationship data extracted from online social networking platforms, as well as their impact on the geolocation recommendation process. In this study, we compare the similarity of geographic locations based on their distance on the ground and their correlation with users who have checked in at those locations. When calculating feature embeddings for users and locations, social relationships are also considered as attention signals. The similarity value between location and correlation between users will be exploited in the overall architecture of the recommendation model, which will employ graph convolution networks to generate recommendations with high precision and recall. The proposed model is implemented and executed on popular datasets, then compared to baseline models to assess its overall effectiveness.