• Journal of the HCI Society of Korea
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• v.5 no.1
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• pp.37-43
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• 2010

Twitter has been continuously growing since October, 2006. Especially, not only the users and the number of messages have been increasing but also a new concept in social networking called 'micro blogging' has diffused. Within Korea, service such as 'me2day' has already been introduced and the improvement of internet accessibility within mobile devices is expected to expand the 'micro blogs'. In this point, this research is executed to study the new medium, 'micro blog'. To do so, we collected and analyzed Twitter logs of Korean users. Especially, we were curious about the extreme heavy users using Twitter, despite of the linguistic and cultural barrier of the foreign service. Who they are, why and how they use the 'micro blog'. First, we reviewed the general aspect of followers and messages by collecting a certain number of random samples. Using the Lorenz curve we found out that there was the imbalance within the users and based on this phenomenon we deducted an extreme heavy user group. In order to perform further analysis, log analysis was performed on the extreme heavy users. As the result, the users used multiple mobile and desktop 'Twitter' clients. The usage pattern was similar to that of internet usage time but was used during their "micro" time. The users using 'Twitter' not only to spread messages about important information, special events and emotions, but also as a habitual 'chatting tool' to express ordinary personal chats similar to SMS and IM services. In this research, it is proved that 68% of the total messages were ordinary personal chats. Also, with 24% of the total messages were retweets, we were able to find out that virtually connected 'people' and 'relationships' acted as the dominant trigger of their articulation.

• Nuclear Engineering and Technology
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• v.50 no.3
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• pp.356-367
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• 2018

A series of tests dedicated to station blackout (SBO) accident scenarios have been recently performed at the $Prim{\ddot{a}}rkreislauf-Versuchsanlage$ (primary coolant loop test facility; PKL) facility in the framework of the OECD/NEA PKL-3 project. These investigations address current safety issues related to beyond design basis accident transients with significant core heat up. This work presents a detailed analysis using the best estimate thermal-hydraulic code TRACE (v5.0 Patch4) of different SBO scenarios conducted at the PKL facility; failures of high- and low-pressure safety injection systems together with steam generator (SG) feedwater supply are considered, thus calling for adequate accident management actions and timely implementation of alternative emergency cooling procedures to prevent core meltdown. The presented analysis evaluates the capability of the applied TRACE model of the PKL facility to correctly capture the sequences of events in the different SBO scenarios, namely the SBO tests H2.1, H2.2 run 1 and H2.2 run 2, including symmetric or asymmetric secondary side depressurization, primary side depressurization, accumulator (ACC) injection in the cold legs and secondary side feeding with mobile pump and/or primary side emergency core coolant injection from the fuel pool cooling pump. This study is focused specifically on the prediction of the core exit temperature, which drives the execution of the most relevant accident management actions. This work presents, in particular, the key improvements made to the TRACE model that helped to improve the code predictions, including the modeling of dynamical heat losses, the nodalization of SGs' heat exchanger tubes and the ACCs. Another relevant aspect of this work is to evaluate how well the model simulations of the three different scenarios qualitatively and quantitatively capture the trends and results exhibited by the actual experiments. For instance, how the number of SGs considered for secondary side depressurization affects the heat transfer from primary side; how the discharge capacity of the pressurizer relief valve affects the dynamics of the transient; how ACC initial pressure and nitrogen release affect the grace time between ACC injection and subsequent core heat up; and how well the alternative feeding modes of the secondary and/or primary side with mobile injection pumps affect core quenching and ensure stable long-term core cooling under controlled boiling conditions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2913-2921
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• 2012

Introduction: The impact of cervical cancer prevention programs depends on persuading women to go for screening and, if needed, treatment. As part of an evaluation of a pilot project in Indonesia, qualitative research was conducted to explore the factors that influence women's decisions regarding screening and treatment and to generate practical recommendations to increase service coverage and reduce loss to follow up. Methods: Research was conducted at 7 of the 17 public health centers in Karawang District that implemented the pilot project. Interviews and focus group discussions were held with 20 women, 20 husbands, 10 doctors, 18 midwives, 3 district health officials, and 16 advocacy team members. Results: Free services and mobile outreach events encouraged women to go for screening, along with promotional efforts by community health workers, advocacy teams, and the mass media. Knowledge and perceptions were the most important barriers to screening: women were not aware of cervical cancer risks, did not know the disease was treatable, and were fatalistic. Factors facilitating treatment were social support from husbands, relatives, and friends and the encouragement and role modeling of health workers. Barriers to prompt treatment included limited access to services and the requirement for husband's consent for cryotherapy. Conclusion: As cervical cancer prevention services are scaled up throughout Indonesia, the findings suggest three strategies to expand screening coverage and ensure prompt treatment: strengthening community mobilization and advocacy activities, modifying the service delivery model to encourage a single visit approach to screening and treatment, and working to gain men's support.

• Korean Journal of Cognitive Science
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• v.22 no.1
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• pp.39-55
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• 2011

People tend to overestimate their emotional reactions to events such as physical handicap and buying a new car in the future. Students overestimate their reactions to a future grade as compared to their reactions after receiving the grade. Impact bias refers to people's tendency to overestimate the intensity and the duration of emotional reactions to a future event. The present study explored whether impact bias occurs to risky objects such as nuclear energy, genetically engineered food, and mobile phone. Participants were asked to predict their emotional reactions at three time points, that is, at the present, a week after, and a year after. They predicted their reactions before and after two debiasing tasks. The present study demonstrated a different pattern of impact bias at three time points: A largest bias was observed a week after the present. A defocalism manipulation has eliminated the impact bias whereas an adaptation manipulation has not. Several points were discussed regarding the difference between the previous and the present work.

• Journal of Multimedia Information System
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• v.1 no.2
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• pp.101-110
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• 2014

The purpose of this research is to extend Ad-hoc network system lifetime with the proposed routing protocol which has considered hop lifetimes of the nodes while guaranteeing QoS in the establishment process of Ad-hoc network communication paths. Based on another power aware routing system that proposed in the advanced research [1], we are proposing an alternative power aware routing system in which nodes' hop lifetimes are compared in order to extend the lifetime of an Ad-hoc network system and delay factors have been considered for the assurance of QoS. The research of the routing protocol in this paper, which aims to maximize the system survival time considering power consumption status during the path searching in MANET and pursues the mechanism that controls hop delays for the same reason, can be applied to the study of WSN. The study concerning such phenomena is essential so that the proposed protocol has been simulated and verified with NS-2 in Linux system focusing on the lifetimes of the hops of the nodes. Commercialization of smart devices and arrival of the ubiquitous age has brought about the world where all the people and things are connected with networks. Since the proposed power aware method and the hop delay control mechanism used to find the adequate communication paths in MANET which mainly uses batteries or in WSN, they can largely contribute to the lifetime extension of the network system by reducing power consumptions when utilized for the communications attempts among soldiers during military operation, disaster areas, temporary events or exhibitions, mobile phone shadow areas, home networks, in-between vehicle communications and sense networks, etc. This paper presents the definitions and some advantages regarding the proposed outing protocol that sustain and extend the lifetime of the networks.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.409-419
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• 2018

The purpose of this study is to examine how the experience factors of KIMAWEEK yacht experience participants affect the experience satisfaction and re-participation intention. this study, 515 KIMAWEEK participants in Pusan metropolitan city conducted a mobile survey and the following conclusions were drawn. First, deviant, educational, and aesthetic factors among the experience factors of yacht experience participants were found to affect the satisfaction of experience, but entertainment factors did not affect it. Second, educational and entertainment factors, among the experiential factors, influenced re-participation intention in relation to the experience factor and re-participation intention, but deviant factors and aesthetic factors did not affect it. Third, the relationship between the experience satisfaction and re-participation intention was also found to have a similar effect. Through this study, various and differentiated experience factors should be provided in order to increase the satisfaction of KIMAWEEK yacht experience participants. In particular, realistic events that meet local characteristics should be held.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.221-227
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• 2014

This paper presented a design which was a minimized remote control robot. This remote control robot was created for preventing life damage from conflagrations, nuclear events and HF gas accidents. This robot's system based smart phone that had camera and GPS systems. When fire came out, The robot figured out that how big fire was, where the fire was started and various aspects of situations. And The robot broadcasted the informations to smart phone using mobile application and wi-fi camera. By doing these, the fire mans could more accurate and be easier to plan a strategy for saving life. The body of robot are 2 parts. One is a car and the other one is a remote controller. By the power, 1step to 10steps, of grabbing remote controller could change the car's speed to move. Also, The prototype robot was already confirmed its utility itself.

• Journal of Communications and Networks
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• v.15 no.5
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• pp.504-513
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• 2013

Communication in delay tolerant networks (DTNs) relies on message transport by mobile nodes, and a correct understanding of the node mobility characteristics is therefore crucial to the design of an efficient DTN routing protocol. However, previous work has mainly focused on uncovering all behaviors of node movement, which is not conducive to accurately detecting the specific movement characteristics of a different node. In this paper, we seek to address this problem based on a consideration of social relationships. We first consider social ties from both static and dynamic perspectives. For a static perspective, in addition to certain accidental events, social relations are considered for a long time granularity and tend to be stable over time. For a dynamic perspective, social relations are analyzed in a relatively short time granularity and are likely to change over time. Based on these perspectives, we adopted different efficient approaches to dividing node pairs into two classes, i.e., familiar and unfamiliar pairs. A threshold approach is used for static social ties whereas a density-based aggregation method is used for dynamic social relationships. Extensive experimental results show that both familiar and unfamiliar node pairs have the same inter-contact time distribution, which closely follows a power-law decay up to a certain point, beyond which it begins to exponentially decay. The results also demonstrate that the inter-contact time distribution of familiar pairs decays faster than that of unfamiliar pairs, whether from a static or dynamic perspective. In addition, we also analyze the reason for the difference between the inter-contact time distributions of both unfamiliar and familiar pairs.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.159-165
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• 2018

In this research, the researcher is seeking how to develop growing O2O food delivery platform service. The food delivery platform is newly creating the profit system which wasn't exist before by adding up IT and new technologies, and young generations who are used to mobile environment have became main consumers. For the methodology of research, internal and external delivery platform cases research is used to suggest the development idea. Food delivery platform market is showing an active development like business expansion by M&A of IT, distribution, manufacturing, circulation and it still has to attract the constant use of consumer through zero commission, discount events. Further research is required for various delivery platform channel and consumer's value of overall experience, above hereafter food delivery platform based on this research.

• Asian Journal of Atmospheric Environment
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• v.8 no.4
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• pp.202-211
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• 2014

In this study, long-term rainfall data with irregular spatial distribution in Seoul, Korea, were separated into individual precipitation events by the inter-event time definition of 6 hours. Precipitation washout of $PM_{10}$ and $NO_2$ concentrations in the air considering various complex factors were analyzed quantitatively. Concentrations of $PM_{10}$ and $NO_2$ in the atmosphere were lower under condition of rainfall compared to that of non-precipitation, and a noticeable difference in average $PM_{10}$ concentrations was observed. The reduction of concentrations of $PM_{10}$ and $NO_2$ by rainfall monitored at road-side air monitoring sites was also lower than that of urban air monitoring sites due to continuous pollutant emissions by transportation sources. Meanwhile, a relatively smaller reduction of average $PM_{10}$ concentration in the atmosphere was observed under conditions of light rainfall below 1 mm, presumably because the impact of pollutant emission was higher than that of precipitation scavenging effect, whereas an obvious reduction of pollutants was shown under conditions of rainfall greater than 1 mm. A log-shaped regression equation was most suitable for the expression of pollutant reduction by precipitation amount. In urban areas, a lower correlation between precipitation and reduction of $NO_2$ concentration was also observed due to the mobile emission effect.