• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.32 no.4
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• pp.137-143
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• 2021

Objectives: Despite the growing concern regarding the adverse effects related to problematic smartphone use (PSU), little is known about underlying morphologic changes in the brain. The brainstem is a deep brain structure that consists of several important nuclei associated with emotions, sensations, and motor functions. In this study, we sought to examine the difference in the volume of brainstem substructures among adolescents with and without PSU. Methods: A total of 87 Korean adolescents participated in this study. The PSU group (n=20, age=16.2±1.1, female:male=12:8) was designated if participants reported a total Smartphone Addiction Proneness Scale (SAPS) score of ≥42, whereas the remaining participants were assigned to the control group (n=67, age=15.3±1.7, female:male=19:48). High-resolution T1 magnetic resonance imaging was performed, and the volume of each of the four brainstem substructures [midbrain, pons, medulla, and superior cerebellar peduncle (SCP)] was measured. Analysis of covariance was conducted to reveal group differences after adjusting for effects of age, gender, whole brainstem volume, depressive symptoms, and impulsivity. Results: The PSU group showed a significantly smaller volume of the SCP than the control group (F=8.273, p=0.005). The volume of the SCP and the SAPS score were negatively correlated (Pearson's r=-0.218, p=0.047). Conclusion: The present study is the first to reveal an altered volume of the brainstem substructure among adolescents with PSU. This finding suggests that the altered white matter structure in the brainstem could be one of the neurobiological mechanisms underlying behavioral changes in PSU.

• Design Convergence Study
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• v.16 no.6
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• pp.169-184
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• 2017

There is a lot of needs that are not expressed as much as the expressed needs in familiar products and services that are used in daily life such as a smartphone. Finding the 'Inconveniences in familiar use' make it possible to create opportunities for value expanding in the existing products and service area. There are a lot of related works, which have studied the definition of hidden needs and the methods to find it. But, they are making it difficult to address the hidden needs in the cases of familiar use due to focus on the new product or service developing typically. In this study, we try to redefine the hidden needs in the daily familiarity and approach it in the new way to find out. Because of the users' unability to express what they want and the complexity of needs which can not be explained clearly, we can not approach it as the quantitative issue. For this reason, the basic data type selected as the user behavior data excluding all description is the screen-shot of the smartphone. We try to apply the integrated rules and patterns to the individual data using the qualitative coding techniques to overcome the limitations of qualitative analysis based on unstructured data. From this process, We can not only extract meaningful clues which can make to understand the hidden needs but also identify the possibility as a way to discover hidden needs through the review of relevance to actual market trends. The process of finding hidden needs is not easy to systemize in itself, but we expect the possibility to be conducted a reference frame for finding hidden needs of other further studies.

• The Journal of the Korea Contents Association
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• v.13 no.5
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• pp.48-57
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• 2013

Smartphones provide users with environment for communication and sharing information and at the same time play an important role of mobile technology and mobile art development. Smartphone technology-related researches are being accelerated especially with the advent of mobile Augmented Reality(AR) age, but the studies on user participation that is essential for AR content industry were insufficient. In that regard, the assistance from mobile art area that has already developed these characteristics is essential. Thus, this article is to classify mobile art that has not been studied a lot domestically into feature phone usage and smartphone usage and to analyze each example case with the three most used methods. The usage of feature phones which use the sound and images of mobile devices can be divided into three: installation and performing methods, single channel video art method and five senses communication method. On the other hand, the usage of smartphones that use sensors, cameras, GPS and AR can be divided into location-based AR, marker-based AR and markerless AR. Also, as a result of examining mobile AR content utilization technology by industries, combined methods are utilized; tourism and game-related industries use location-based AR, education and medicine-related industries use marker-based AR, and shopping-related industries use markerless AR. The development of AR content industry is expected to be accelerated with mobile art that makes use of combined technology method and constant communication method through active participation of users. The future development direction of mobile AR industry is predicted to have minimized HMD, integration of hologram technology and artificial intelligence and make the most of big data and social network so that we could overcome the technological limitation of AR.

• The Journal of the Korea Contents Association
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• v.20 no.7
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• pp.1-18
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• 2020

Fine dust is one of the top ten causes of deaths globally. More than 95% of the world's population are endangered by it. However, as the fine dust problem is difficult to address immediately, people should be informed of its risk and prepared to deal with it. This study explores the methods used to define, efficiently provide, and manage the complementary relationships between various types of media providing risk information utilizing the competitive characteristics of media in niche theory. A survey consisting of 348 Korean university students was conducted over 12 days, to analyze three factors: consumer perception of fine dust, media usage, and media use gratification. The response value for media gratification was substituted in the equation to derive the niche breadth, niche overlap, and competitive superiority. It was found that 1) for providing fine dust forecast and fine dust response guidance information, a smartphone application was the most effective; 2) smartphone applications were limited in providing additional information such as the severity and origin of fine dust, and hence, it is necessary to establish the functionality of the Internet and TV to complement smartphone applications. Thus, a system considering the above should be developed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.6
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• pp.199-206
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• 2012

Attempt to use as a marker of natural objects directly in the real world, but there is a way to use the accelerometer of the smartphone, to convert the Frontal-View virtual, because it asks only the pitch of the camera, from the side there is a drawback that can not be converted to images. The proposed algorithm, to obtain the rotation matrix of axis 3 pitch, roll, yaw, we set the reference point of the yaw of the target image. Then, to compensate for the rotation matrix to determine Myon'inji any floor, wall, the ceiling of the target image. Finally, to obtain the homography matrix for obtaining the Frontal-View to account for the difference between the gyro sensor coordinate system and image coordinate system, so we can get the Frontal-View from the captured images through the projection transformation was designed. Was tested to convert Frontal-View the picture was taken in an environment smartphone environment surrounding floor, walls and ceiling in order to evaluate the conversion program Frontal-View has been implemented, in this paper, design and The conversion algorithm implementation, it was confirmed that to convert a regular basis Frontal-View footage taken from multiple angles.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.102-111
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• 2011

This paper aimed at smartphone applications of department store brands in order to examine the traits of applications for the brand image. The study carried out survey research with 114 smartphone users who experienced the application of a department store, assuming that the design, contents, ease of use, and community characteristics of the application would affect satisfaction and the brand image. This paper performed a confirmatory factor analysis, correlation analysis, and the test of a model using PLS. Results showed that the design and contents of the application affected the improvement of satisfaction and of a brand image, whereas ease of use did not affect satisfaction and brand image. Also, community was influential on satisfaction, whereas it was not influential on the improvement of a brand image. Satisfaction with the application showed a strong impact on the improvement of a brand image; thus, it was found necessary for upcoming brand applications to enhance satisfaction for building a positive brand image.

• KIPS Transactions on Computer and Communication Systems
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• v.7 no.5
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• pp.127-136
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• 2018

In this paper, we propose a PIN entry method that combines with machine learning technique on smartphone. We use not only a PIN but also touch time intervals and locations as factors to identify whether the user is correct or not. In the user registration phase, a remote server was used to train/create a machine learning model using data that collected from end-user device (i.e. smartphone). In the user authentication phase, the pre-trained model and the saved PIN was used to decide the authentication success or failure. We examined that there is no big inconvenience to use this technique (FRR: 0%) and more secure than the previous PIN entry techniques (FAR : 0%), through usability and security experiments, as a result we could confirm that this technique can be used sufficiently. In addition, we examined that a security incident is unlikely to occur (FAR: 5%) even if the PIN is leaked through the shoulder surfing attack experiments.

• Journal of Korea Game Society
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• v.16 no.3
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• pp.27-34
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• 2016

New game systems have emerged with the rapid growth of Korea smartphone game industry. Especially auto battle system introduced in RPG which is the most popular genre, which has brought a significant change in the understanding of the computer games. To understand this change, it is necessary to look at what circumstances did emerge auto battle system. What is important here is the smart phone as the technical apparatus which defines the presence of a smart phone game, and the use pattern of the smart phone. the technical device and Its use pattern are affecting the activity of the user how to play the game, game developers are to create the game system according to this play style. By examining the appearance and growth of this auto battle system, we can confirm that the micro changes in the game system, reflect changes in the present form of a computer game. This fact will widen the understanding of the history of computer games.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.51-57
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• 2015

In this paper, we tried to broaden a width of practical use field for applications through combining to existing contents after constructing various contents for companion animals. For this, we designed and developed our new companion animal management system(PET-IN) by adding various contents such as information management, schedule management, health management, QR code, SNS, shopping, map service for companion animals to smartphone applications. By PET-IN accessibility and satisfactory level tests, we found out that new synergy effect have appeared through combining each contents, and connectivity is increased. So, practical use field is broaden. These tests show us that comprehensive content composition is necessary for companion animal applications, and this study can be used as important data when new companion animal application contents are constructed in the future.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.3
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• pp.519-525
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• 2014

In this paper, we show a scheme to directly access DLNA network with the 3G/4G communication module of a smartphone in home or office environment. By exploiting this scheme, end users can use DLNA service more conveniently regardless of the type of activated communication module in a smartphone. For the implementation of this scheme, we use a femtocell that is a basestation with small coverage. A problem caused by the IP address hierarch discrepancy between the IP address of 3G/4G module of smartphone and those of local network nodes is resolved by deploying local IP address scheme. The processing of multicasting packet, that is required in DLNA service, is enabled by using IP tunneling scheme. As a result, end user can access DLNA network regardless of the type of activated wireless communication module. We validate the design result by implementing it on a commercial WCDMA femtocell.