• The Journal of Korean Physical Therapy
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• v.32 no.4
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• pp.198-202
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• 2020

Purpose: This study examined the effects of a paraffin treatment with exercise on the muscle strength and fatigue of the hand according to the use of smartphones. Methods: The measurement subjects were 30 healthy males in their 20s who were divided randomly into the control and paraffin treatment groups. A typing exercise using a smartphone was performed. The pinch grip force was measured to evaluate the muscle strength of the thumb, and muscle fatigue analysis using electromyography was performed to analyze muscle fatigue. Results: The functional changes to the arm and the fatigue of the hand through the use of a smartphone were examined to determine the effects of the paraffin treatment. The dominant hand-pinch grip force test did not show a significant difference, but the non-dominant hand-pinch grip force test showed a significant difference between the groups (p=0.030). In the dominant hand fatigue test, there was a significant difference between the groups (p=0.037). In the non-dominant hand, there was a significant difference between time (p=0.012) and the groups (p<0.001). Conclusion: The effects of paraffin intervention on the hand muscle strength and fatigue due to repeated use of the smartphone were confirmed. These results can be used as a basis for clinical use and can be a guide for the correct use of smartphones, which are essential in modern life.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.2
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• pp.131-138
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• 2017

Lately, Internet-based vessels have begun to appear at sea with the development of ICT. Thereby crews have gained easy Internet access through increased smartphone portability. However, the side effects of smartphone use while on watch, have not been studied seriously despite being a reality. In this study, simulation experiments were carried out using a Ship Handling Simulator in order to distinguish the risks of using a smartphone while on watch. Proximity Evaluation, Control Evaluation, Subjective Evaluation and Situation Awareness to the dangerous situation were used to quantify risk during simulation, and analysis results were compared with cases when using and not using a smartphone. It was found that the degree of risk increased between 1.3 to 3 times given smartphone use. Consequently, this paper represents foundation for the restriction of smartphone use and proposes smartphone usage guideline for ship navigation.

• Korean Journal of Computational Design and Engineering
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• v.16 no.5
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• pp.361-369
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• 2011

As smartphones came into wide use recently, it has become increasingly popular not only among young people, but middle-aged people as well. Most smartphones use capacitive full touch screen, so touch commands are made by fingers unlike the PDAs in the past that use touch pens. In this case, a significant portion of the smartphone's screen is blocked by the finger so it is impossible to see the screens around the finger touching the screen, and difficulty occurs in precise control used for small buttons such as qwerty keyboard. To solve this problem, this research proposes a method of using simple AR markers to improve the interface of smartphones. Sticker-form marker is attached to fingernails and placed in front of the smartphone camera Then, the camera image of the marker is analyzed to determine the orientation of the marker to perceive as onRelease() or onPress() of the mouse depending on the marker's angle of rotation, and use its position as the position of the mouse cursor. This method can enable click, double-click, drag-and-drop used in PCs as well as touch, slide, long-touch-input in smartphones. Through this research, smartphone inputs can be made more precise and simple, and show the possibility of the application of a new concept of smartphone interface.

• Informatization Policy
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• v.25 no.4
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• pp.65-83
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• 2018

This study examined the effects of smartphone usage types and excessive expectation for smartphone on adolescents' smartphone overdependence. It utilized the data of 3,454 adolescents (1,758 males and 1,696 females), aged between 13 and 19 from a smartphone overdependence survey of the National Information Society Agency. As a result of the hierarchical multiple regression analysis, age and household income had a negative effect on smartphone overdependence. Weekly smartphone usage time positively affected the serious consequences (sub-factor of smartphone overdependence). Among the different types of smartphone usage, information seeking, SNS, gaming, and the excessive expectation for smartphones had positive impact on smartphone overdependence. Smartphone usage for leisure seeking did not affect smartphone overdependence, but it negatively influenced serious consequences. Messenger use did not affect smartphone overdependence, but the use had a positive effect on salience, and a negative effect on serious consequences. The results of this study suggest that it is necessary to identify the types of smartphone use as well as the usage time to understand the smartphone dependence of adolescents. In addition, it seems necessary to recognize and correct the irrational excessive expectation for smartphone in order to prevent dependence and implement effective interventions.

• International journal of advanced smart convergence
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• v.10 no.3
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• pp.10-16
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• 2021

In this paper, we devise a Shapley-value-based covert channel in smartphones. More specifically, unlike ordinary use of Shapley value in cooperative game, we make use of a series of Shapley values, which are computed from sensor data collected from smartphones, in order to create a covert channel between encoding smartphone and decoding smartphone. To the best of our knowledge, we are the first to contrive covert channel based on Shapley values. We evaluate the encoding process of our proposed covert channel through simulation and present our evaluation results.

• The Journal of Information Systems
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• v.21 no.3
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• pp.71-97
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• 2012

There has been an upward trend in smartphone sales in Korea as well as the rest of the world. Even though smartphones are now at the peak of their popularity, the fact that they are somewhat limited in terms of their usages for certain purposes is unexpected. Precisely, compared to PC, smartphones typically have smaller display screens with a lower resolution, which make them difficult to use in general. For instance, when customers search the information about products in mobile shopping malls, due to the smaller screen with a low resolution smartphone users may realize that it is not easy and convenient not only to search the information, but also to read the information they found in the shopping malls. This restriction could become one of reasons that lowers the perceived quality of information in the shopping malls, which in turn leads to the reluctance to use the shopping malls. A comprehensive information systems (IS) literature review found that there has been little empirical evidence on perceived information quality that affects smartphone users' intention to use mobile shopping malls. The purposes of this study is to examine 1) the effects of perceived information quality on smartphone users' intention to use mobile shopping malls and 2) the relationships among behavioral beliefs in the middle of independent and dependent variables, such as information satisfaction, perceived usefulness, and customers' attitude toward mobile shopping. A survey was conducted in March 2012. College students and practitioners took participated in the survey. Structural Equation Modeling(SEM) was used for all data analysis. The results found that there is a strong relationship between perceived information quality and smartphone users' intention to use mobile shopping malls. In addition, this study also showed that there are strong relationships among behavioral beliefs. Further research is expected to validate the findings of this study and apply them in specific contexts.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.23-30
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• 2022

This study is an exploratory study to examine the relation between parents and children's smartphone usage time. The data from the 11th Korea Media Panel Survey conducted by the Korea Information Society Development Institute was used for empirical analysis. The findings revealed that parents' smartphone usage time and children's smartphone usage time are positively correlated, indicating that their smartphone use patterns share similarities as members of a family system. This study lays the foundation for future work to explain individual media use through family and media use environment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.479-494
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• 2020

The purpose of this study is to systematically analyze through structural relationship analysis the relationship between excessive smartphone use by adolescents and school adaption. A questionnaire was administered to 866 elementary, middle and high school students who are using smartphones SEM was applied to the analysis with the following results. First, the relationship between excessive smartphone use and school adaptation was not significant. Second, the relationship between social support and excessive smartphone use had significant influence. Third, there is a significant influence in the relationship between self-control and excessive smartphone use. Fourth, social support and self-control of adolescents had a direct influence on school adaptation. Fifth, social support and self-control mediate the relationship between smartphone overuse and school adaptation. Therefore, increasing the adaptability of adolescents requires efforts to firm social support system by expanding autonomous sense or self-control personally and mutual support in the family.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.3
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• pp.285-296
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• 2014

Recently, the use of Smartphones has been widespread and changed our lives positively. Smartphones which are called as PC in the hand and spread general people rapidly are becoming a medium to use generally various functions such as internet, work, multimedia, etc. beyond the simple function of telephone communication in the past. However, the excessive use of Smartphones has also produced many side effects. The purpose of this study is to examine the Smartphone Addiction on Daily Life Impact. This model tests various theoretical research hypotheses relating to Self-Esteem, Enjoyment, Flow, Social Impact, Smartphone Addiction and Daily life impact. The proposed model is analyzed to target 299 University Students and Smart Partial Least Square(PLS) 2.0 have been utilized for deriving the study results. The Result of Hypothesis testing are as follows. First, Self-Esteem negatively influence Smartphone Addiction. Second, Enjoyment, Flow and Social Impact positively influence Smartphone Addiction. Third, Smartphone Addiction positively influence Daily Life impact. This Research makes a basic research for smart phone addiction papers that will be investigated a lot in the future.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.139-149
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• 2011

Smartphone is a new information technology that converges PDA into a mobile phone. Based on the Technology Acceptance Model, this study examines factors influencing the intention to use smartphone. Independent variables of this research are composed of the subjective norm, innovativeness, perceived usefulness, perceived ease of use, perceived enjoyment, cost relevance. Questionnaires are collected from 289 students who are using a smartphone. The results are following: first, the subjective norm, innovativeness, perceived usefulness, the perceived enjoyment, and cost relevance have positive effect on the intention to use smartphone, but the perceived ease of use has not. Second, the perceived enjoyment is found to be the strongest predictor of the intention to use.