• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.5
• /
• pp.599-604
• /
• 2019

This study examined how the characteristics of smartphone affect the functional performance of smartphones. In particular, this study focused on an understanding of the correlation between smartphone functional factors and usage habits. Functionality is defined as 11 kinds of functional elements. The characteristics of the smartphones were defined as the hardware characteristics and the user habits characteristics. Eighty subjects were organized to collect actual data by the smartphone function. The actual time required to perform each function was measured and observed five times for each functional element. Regression analysis was performed using Minitab ver.14 by classifying the measured values of the functional elements as dependent variables, the hardware characteristics collected through the questionnaire, and the user's usage habits as 12 independent variables. Overall, it is difficult to conclude that demographic and hardware characteristics of smartphone users have a significant effect on the performance. On the other hand, the variables related to smartphone usage habits have had a great impact on the performance of smartphone tasks, and as a result, the task execution time has increased. In simple input variables or viewing variables, the effects on usability was relatively small, but in all active variables, the execution time increased 10% - 30% in all tasks except for phone calls, seeking phone numbers, and dictionary search. Thus far, if the smartphone user interface has been provided uniformly in a large and simple manner, users with various usage habits can be utilized even if the input method and task processing method are more complicated and various interface types are provided.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.9 no.5
• /
• pp.277-283
• /
• 2014

In this paper, we propose a control system for synchronizing attitude between an Android smartphone and a mobile robot. The control system is comprised of a smartphone and a mobile robot. The smartphone transports its attitude to the mobile robot and receives the attitude of mobile robot through bluetooth communication. Further, the smartphone displays the mobile robot on the screen by using embedded camera, which can be used as a pseudo augmented reality. Comparing the received attitude data from smartphone, the mobile robot measures its attitude by an AHRS(attitude heading reference system) and controls its attitude. Experiments show that the synchronization performance of the proposed system is maintained in the error range of $1^{\circ}$.

• Journal of the Korea Safety Management & Science
• /
• v.15 no.4
• /
• pp.323-330
• /
• 2013

The number of domestic smartphone users exceeded 30 million people, and the time in the future everyone will use a smartphone that will come with ago. Past purchase decisions, related research and product from the competition between the past case and the relevant literature for the smartphone market smartphone type to derive a purchase decision factors in the decision to purchase any difference between the factors. Literature and practices through performance, switching costs, product loyalty, design, brand, after-sales service, the price more than 7 variables were analyzed. One hundred people surveyed, respectively, did not obtain the response of a variety of ages and occupations, age of the sample used in the analysis of this study, and is concentrated as a student at the university of smartphones used to facilitate users analysis was done. We expect smartphone companies and related companies to be able to give guidelines for effective technology management.

• Korea Journal of Hospital Management
• /
• v.26 no.4
• /
• pp.12-28
• /
• 2021

Purposes: The convenience of smartphones have lead to people's overdependence on devices, which may cause obstacles in daily life. It is useful to manage smartphone overdependence by using mobile health applications. We aimed to investigate the acceptance of mobile health applications designed to help in the management of smartphone overdependence. Methodology/Approach: We developed the extended model based on the Unified Theory of Acceptance and Use of Technology 2. The modified model had six hypotheses with six variables: result demonstrability, performance expectancy, effort expectancy, social influence, perceived risk, and behavioral intention to use. We randomly included 425 smartphone users in an online survey in 2020. A structural equation model was used to estimate the significance of the path coefficients. Findings: Performance expectancy and social influence had a very strong direct positive association with behavioral intention to use. Result demonstrability had a direct positive association with performance expectancy. Perceived risk had a strong direct negative association with performance expectancy. Performance expectancy and social influence were the main factors directly influencing the acceptance of mobile health applications for the management of smartphone overdependence. Practical Implications: We demonstrated smartphone users' acceptance of mobile health applications for smartphone overdependence management. Based on these results, we could develop mobile health applications more effectively.

• Journal of the Korean Society of Visualization
• /
• v.10 no.2
• /
• pp.25-31
• /
• 2012

High-performance smartphones, equipped with a digital camera and an application software, can render conventional bench-top laboratory instruments mobile at affordable costs. As the smartphone-based devices are portable and wireless, they have wide applications especially in providing point-of-care (POC) tests in resource-constrained areas. We developed a hand-held diagnostic system, Mobile SmartScope, which consists of a small optical unit integrated with a smartphone. The performance of the SmartScope was favorably compared with that of conventional light microscopy in detecting and quantifying red blood cells. We also evaluated the fluorescence detection limit of the SmartScope incorporated with a blue light-emitting diode and appropriate optical filters by using fluorescently labeled microbeads for intensity calibration.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.2
• /
• pp.153-163
• /
• 2011

Smartphone is a mobile device which can perform better than feature phone. Recently, growth in demand for advanced mobile devices boasting powerful performance, market share of smartphone is increasing rapidly in mobile device market, for example, iphone and android phone. Smartphone can provide many functionalities, e-mail, scheduler, word-processing, 3D-game, and etc, based on its powerful performance. Thus, various secret information is integrated in smartphone. To provide service, sometimes, smartphone transmits informations to outside via wireless network. Because smartphone is a mobile device, user can lose his/her smartphone, easily, and losing smartphone can cause serious security threats, because of integrated information in smartphone. Also data which is transmitted in wireless network can be protected for privacy. Thus, in present, it is very important to keep secure smartphone. In this paper, we analyze threats and vulnerabilities of smartphone based on its environments and describe countermeasures against threats and vulnerabilities.

• Journal of Korean Academy of Nursing
• /
• v.46 no.2
• /
• pp.283-292
• /
• 2016

Purpose: This study was done to verify effects of a self-directed feedback practice using smartphone videos on nursing students' basic nursing skills, confidence in performance and learning satisfaction. Methods: In this study an experimental study with a post-test only control group design was used. Twenty-nine students were assigned to the experimental group and 29 to the control group. Experimental treatment was exchanging feedback on deficiencies through smartphone recorded videos of nursing practice process taken by peers during self-directed practice. Results: Basic nursing skills scores were higher for all items in the experimental group compared to the control group, and differences were statistically significant ["Measuring vital signs" (t=-2.10, p=.039); "Wearing protective equipment when entering and exiting the quarantine room and the management of waste materials" (t=-4.74, p<.001) "Gavage tube feeding" (t=-2.70, p=.009)]. Confidence in performance was higher in the experimental group compared to the control group, but the differences were not statistically significant. However, after the complete practice, there was a statistically significant difference in overall performance confidence (t=-3.07. p=.003). Learning satisfaction was higher in the experimental group compared to the control group, but the difference was not statistically significant (t=-1.67, p=.100). Conclusion: Results of this study indicate that self-directed feedback practice using smartphone videos can improve basic nursing skills. The significance is that it can help nursing students gain confidence in their nursing skills for the future through improvement of basic nursing skills and performance of quality care, thus providing patients with safer care.

• Journal of Korea Society of Industrial Information Systems
• /
• v.19 no.6
• /
• pp.131-150
• /
• 2014

This study investigates factors, which affect subjective judgment of Smartphone users when they switch to a new product or other mobile carrier, and examine a relationship between switching intention and switching expected performance through users of in Korea and China. The results of the study showed that switching intention is positively associated with switching expected performance in both Korean and Chinese users. Brand reliability, functional quality, and general climate for Smartphone business have a significant impact on switching intention in both countries. In addition, personal innovation has a significant impact on switching intention of Korean users but Chinese. However, content quality has the effect on switching intention of Chinese user but Korean. This study provides useful strategies for switching behavior of Smartphone users of two different countries in the mobile industry.

• Korean Journal of Remote Sensing
• /
• v.32 no.1
• /
• pp.49-60
• /
• 2016

This paper presents a set of methods to evaluate the image quality of smartphone cameras as compared with that of a DSLR camera. In recent years, smartphone cameras have been used broadly for many purposes. As the performance of smartphone cameras has been enhanced considerably, they can be considered to be used for precise mapping instead of metric cameras. To evaluate the possibility, we tested the quality of one DSLR camera and 3 smartphone cameras. In the first step, we compare the amount of lens distortions inherent in each camera using camera calibration sheet images. Then, we acquired target sheet images, extracted reference lines from them and evaluated the geometric quality of smartphone cameras based on the amount of errors occurring in fitting a straight line to observed points. In addition, we present a method to evaluate the radiometric quality of the images taken by each camera based on planar fitting errors. Also, we propose a method to quantify the geometric quality of the selected camera using edge displacements observed in target sheet images. The experimental results show that the geometric and radiometric qualities of smartphone cameras are comparable to those of a DSLR camera except lens distortion parameters.

• The Journal of Information Systems
• /
• v.26 no.1
• /
• pp.143-169
• /
• 2017

Purpose With the increase of the elderly population, the growth of its information system related market is increasing. However, empirical studies for the usage of elderly people's smartphones are still limited. This study aims to investigate the factors that affect the seniors' smartphone usage behaviors. Design/Methodology/Approach First, a preliminary study was conducted with targeting seniors who have visited Gwangju Senior Technology Center(GSTC) in order to understand the factors that affect the intention of utilizing smartphones. Next, based on the preliminary study results and literature reviews including the UTAUT model, performance expectancy, effort expectancy and social influence were considered for the major factors affecting the usage of elderly people's smartphones. Also, the moderate effects of personal innovativeness and usage function were discussed. A questionnaire survey of 181 seniors visiting GSTC was analyzed to empirically test the research model. Findings By the empirical tests, the performance expectancy and the effort expectancy of the seniors had significant impacts on their smartphone usage behavior. While the moderating effect of personal innovativeness was not significant, the moderating effect of the usage function was significant in the relationship between performance expectancy and the smartphone usage behavior. The results of this study are expected to provide guidelines to excavate the technical development and the niche market targeting the elderly people.