• Korean Journal of Applied Biomechanics
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• v.30 no.2
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• pp.155-163
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• 2020

Objective: This study to identify the mechanism of head impact that occurs during youth soccer game with regard to head injuries in sports. Method: Ten male subjects (age: 10.0±2.0 yrs.) were participated during 10 soccer practices spread out over a time period of 10 weeks. During each soccer game, the participants agreed and wore the X-Patch (wireless accelerometer, gyroscopes). The X-Patch records the head impact mechanics, such as peak linear acceleration (PLA), peak rotational acceleration (PRA), peak rotational velocity (PRV), Head Injury Criterion (HIC), and the location of impact. Results: A total of 501 impacts to the head were measured over the 10 soccer games, PLA 17.8±10.4 g, PRA 3168±2442 rad/s²; PRV 16.1±10.6 rad/s; HIC 11.7±34.2. The severity of impact was classified into 3 ranges; low 10~39 g (482 impacts); medium 40~69 g (17 impacts); and high >69 g (2 impacts). There are no significant differences in PLA and HIC (p=0.08, p=0.15), however PRA and PRV show the differences (p<.05) between each of the participants. For the analysis comparing between the soccer games, there are no significant differences in PLA, PRA, PRV and HIC (p=0.11, p=0.13, p=0.14, p=0.05). Conclusion: Our results indicated that there were significant differences between athletes, especially in terms of rotational acceleration, whereas there were significant differences in linear and rotational based variable between each of the soccer games. Although the vast majority of impacts were below 39 g there were 2 potentially dangerous impacts above 69 g. It is important that future research continuous to measure head impact mechanics during soccer to help understand head injury mechanisms to ensure the safety of athletes.

• Journal of Communications and Networks
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• v.11 no.4
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• pp.359-367
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• 2009

Trust-based solutions provide some form of payment to peers to encourage good behavior. The problem with trust management systems is that they require prior knowledge to work. In other words, peers are vulnerable to attack if they do not have knowledge or correct knowledge of other peers in a trust management system. Therefore, considering only trust is inadequate when a decision is made to identify the best set of peers to utilize. In order to solve the problem, we propose a distributed decision-making mechanism for wireless peer-to-peer (P2P) networks based on game theory and relevant trust mechanisms in which we incorporate the element of trust and risk into a single model. The main idea of our mechanism is to use utility function to express the relationship between benefits and costs of peers, and then make the decision based on expected utility as well as risk attitude in a fully distributed fashion. The unique feature of our mechanism is that it not only helps a peer to select its partners, but also mitigates vulnerabilities in trust-based mechanisms. Through analysis and experiments, we believe our approach is useful for peers to make the decision regarding who to interact with. In addition, it is also a good starting point for exploring tradeoffs among risk, trust and utility.

• Korean Journal of Applied Biomechanics
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• v.24 no.4
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• pp.455-461
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• 2014

The purposes of this study were to reveal the kinematic and kinetic difference of hard ground soccer shoe, firm ground soccer shoe and soft ground soccer shoe. Soccer players were shoes of varying stud designs with some preferring the bladed studs while others opting for the conventional studded stud. Statistics were used one way-ANOVA and Tukey's Honestly Significant Difference Method. Seven healthy college soccer players were attended a test. All parameters were recorded using the Zebris system. Spatio-temporal variables were no significant difference. Lateral symmetry was statistically significant differences (p<.05). Vertical GRF parameters were no significant difference. Medial midfoot pressure, lateral midfoot pressure and central forefoot pressure were statistically significant differences (p<.05). This study demonstrates that playing surface significantly affects difference soccer shoes during soccer game. Furthermore, epidemiological investigation is warranted to determine the effects of playing surfaces on sport specific injury mechanisms.

• Journal of Korea Multimedia Society
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• v.25 no.9
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• pp.1348-1355
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• 2022

This study will be an exploratory study from the perspective of IWOM on the intention of word-of-mouth transmission. And based on 256 questionnaire survey data of E-Commerce live broadcast consumers, structural equation modeling is used to explore the paths and mechanisms of influence of consumers' perceived IWOM and perceived value on oral transmission intention in China's E-Commerce live broadcast. The results found that consumers' perceived IWOM had a positive effect on perceived usefulness and perceived entertainment, and that perceived usefulness had a positive effect on purchase intention while perceived entertainment had no direct effect on word-of-mouth transmission intention. Perceived IWOM also indirectly influences willingness to pass on word-of-mouth by affecting perceived value. Among them, the mediating effect of perceived usefulness in the path of perceived network influence on word-of-mouth transmission intention is greater than that of perceived entertainment.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.332-337
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• 2023

The purpose of the study was to analyze consumers' perceptions of gamification. Based on the analyzed data, we would like to provide data by systematically organizing the concept, game elements, and mechanisms of gamification. Recently, gamification can be easily found around medical care, corporate marketing, and education. This study collected keywords from social media portal sites Naver, Daum, and Google from 2018 to 2023 using TEXTOM, a social media analysis tool. In this study, data were analyzed using text mining, semantic network analysis, and CONCOR analysis methods. Based on the collected data, we looked at the relevance and clusters related to gamification. The clusters were divided into a total of four clusters: 'Awareness of Gamification', 'Gamification Program', 'Future Technology of Gamification', and 'Use of Gamification'. Through social media analysis, we want to investigate and identify consumers' perceptions of gamification use, and check market and consumer perceptions to make up for the shortcomings. Through this, we intend to develop a plan to utilize gamification.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.445-446
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• 2020

최근 사물인터넷의 발전에 따른 많은 기기들이 디지털화 되면서 네트워크의 새로운 주요 장비로 등장하고 있으며 이 중 CCTV의 경우 대부분 IP를 갖는 독립적인 네트워크 디바이스가 되고 있다. 하지만 이러한 CCTV의 네트워크 접근에 따른 해킹 가능성이 끊임없이 제공되면서 CCTV를 통한 내부망의 침투가 현실적으로 가능한 상황이다. 현재 대부분의 영상 화면이 암호화되어 운영되고는 있지만 CCTV를 통제하는 제어 데이터는 어떠한 보안조치도 이루어지지 않은 것이 현실이다. 이러한 점을 보완하기 위해 면에서 본 논문에서는 CCTV 통제를 위한 제어 데이터도 인증 및 암호화를 통해 일반적인 접근을 완전히 차단할 수 있는 방안을 제시하고 이를 통한 사물인터넷의 안정성을 검증하는 방안을 제안하고자 한다.

• Archives of design research
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• v.19 no.1 s.63
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• pp.119-128
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• 2006

'Play' itself is enough of a motivation for anyone to do it. Still, it will be very difficult to continue to enjoy meaningless and aimless repetition of fights, mimicking, chases, discoveries or changing of sceneries by the mechanism alone. Of course, in rare occasions there are games like Tetris which can be enjoyed on its great gameplay alone for hours. But for most cases, players need goals, initiatives, and dynamism through storytelling for their experiences to be a rich one. Validity and feasibility of storytelling in games has always existed with plenty of skepticism. However, as games evolved from some small play mechanisms for spare times to a major entertainment with recognizable volume and content, a need to keep players interested and participating has made storytelling an essential ingredient. Storytelling within games has to have different meanings and shapes to existing narratives. Hence, new definition and methodology must emerge and studies has been active. If a case can be made so that a tested and tried methodology that has been successful for other media can be substituted for games, then it can bring a new direction to the ongoing studies. This study will borrow some methodology from cinema which can sometimes be seen as opposite to games and sometimes as something games want to be alike.

• Asia pacific journal of information systems
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• v.25 no.4
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• pp.763-783
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• 2015

Online customer reviews (i.e., electronic word-of-mouth) has gained considerable interest over the past years. However, a knowledge gap exists in explaining the mechanisms among the factors that determine the product sales in online retailing environment. To fill the gap, this study adopts a principal-agent perspective to investigate the effect of customer reviews and customer incentives on product sales in online retail stores. Two customer review factors (i.e., average review ratings and the number of reviews) and two customer incentive factors (i.e., price discounts and special shipping offers) are used to predict product sales in regression analysis. The sales ranking data collected from the video game titles at Amazon.com are used to analyze the direct effects of the four factors and the interaction effects between customer review and customer incentive factors to product sales. Result reveals that most relationships exist as hypothesized. The findings support both the direct and interaction effects of customer reviews and incentive factors on product sales. Based on the findings, discussions are provided with regard to the academic and practical contributions.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.896-899
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• 2002

In this paper, we present the experimentation and demonstration results of Korea-Japan high-speed satellite ATM network using Ka-band Koreasat-3. This experimentation consists of two items - TCP/IP and MPEG-2 video/audio transmission over 155Mbps ATM based satellite network. The goals of this experimentation are to measure TCP performance when the only standard mechanisms approved by IETF in order to improve TCP performance in LFN(long fat network) are used and to derive the effects of quality for the high definition video stream when MPEG-2 TS is transmitted through 155Mbps satellite ATM link. With on the results of the experiments, we demonstrated the applications suitable to the high-speed satellite ATM network. The first TCP/IP and MPEG-2 transmission experiments were done at the rate of 155Mbps using Ka-band KOREASAT-3 between Korea and Japan, and its results will be demonstrated with the ATM-based 3D-HDV(3 dimensional High definition video) and HDTV during 2002 Korea-Japan World Cup Soccer Game.

• Journal of Internet Computing and Services
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• v.8 no.4
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• pp.137-147
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• 2007

As Web-based online communities are rapidly growing, the agents in social groups need to know their measurable belief of trust for safe andsuccessful interactions. In this paper, we propose a computational model of trust resulting from available feedbacks in online communities. The notion of trust can be defined as an aggregation of consensus given a set of past interactions. The averagetrust of an agent further represents the center of gravity of the distribution of its trustworthiness and untrustworthiness. And then, we precisely describe the relationship between reputation, trust, and averagetrust through a concrete example of their computations. We apply our trust model to online internet settings in order to show how trust mechanisms are involved in a rational decision-making of the agents.