• Journal of the Korea Convergence Society
• /
• v.10 no.5
• /
• pp.189-201
• /
• 2019

The aim of this study is to investigate the relationship between communication motive, fatigue and loneliness in mobile environment. According to previous research, the most important communication motive in mobile environment is pleasure. Therefore, pleasure was selected as a representative communication motive. To do this, we collected data for empirical analysis from mobile messenger users using questionnaire. We found that pleasure has a negative effect on loneliness. Second, pleasure has a negative effect on connection, function, and focus. On the other hand, pleasure has no effect on delivery and relationship fatigue. Finally, function and focus have a positive effect on loneliness. On the other hand, connection, delivery, and relationship fatigue have no effect on loneliness. As a result of the research, it is possible to reduce the function and focus fatigue due to the use of the mobile messenger by adding the functions that cause the enjoyment of using the messenger. In addition, the addition of fun-inducing features can also reduce loneliness caused by the use of mobile messenger. Future research will also need to identify factors that may reduce connection and relationship fatigue.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.1506-1510
• /
• 2004

A mobile robot system is developed to inspect the condition of industrial facilities under hot environment. The mobile robot is equipped with internal and external heat insulating material, an internal cooling mechanism, two CCD cameras, wireless communication devices for both the control and image signals, and an embedded controller. The portable controller is equipped with two joysticks for both the mobile robot and the inspection CCD camera, an LCD monitor, and several buttons. The developed mobile robot travels on the internal floor in hot furnaces by operators' joystick operation, captures the images of facilities in the furnaces using a zoom CCD camera, and sends the images to the portable controller through wireless communication. The mobile robot can be operated without any problem under hot environment less than 400$^{\circ}C$ in 30 minutes. This kind of automatic inspection mobile robot can be helpful to prevent significant troubles of industrial facilities without danger of human beings under harmful environment.

• Journal of Institute of Control, Robotics and Systems
• /
• v.22 no.2
• /
• pp.75-82
• /
• 2016

Visible light communication (VLC) using LED lamps is suitable for implementing an indoor positioning system in an indoor environment where the global positioning system (GPS) signal does not reach. In this paper, we present an indoor positioning system for mobile robots using a VLC beacon and fuzzy rules. This system consists of an autonomous mobile robot, VLC modules, and device application software. Fuzzy rules are applied to plan the global and local paths along which the mobile robot navigates indoors. The VLC transmitter modules are attached to the wall or the ceiling as beacons to transmit their own location information. The variable pulse position modulation (VPPM) algorithm is used to transmit data, which is a new modulation scheme for VLC providing a dimming control mechanism for flicker-free optical communication. The mobile robot has a receiver module to receive the location information while performing its mission in the environment where VLC transmitters are deployed.

• Electronics and Telecommunications Trends
• /
• v.33 no.1
• /
• pp.111-122
• /
• 2018

In this review, several new technologies considered when providing an open service environment in a mobile communication network are described. Recently, 3GPP developed some standards related to IoT services for opening a service platform in an SCS environment based on the OSA concept in a 3GPP LTE system. Similarly, the development of a new framework is underway to allow a plurality of services to commonly use an API environment in which a service provider or client accesses a 5G mobile communication system. Extending the existing LTE SCEF concept, the standardization of the northbound API is applied in the 5G CAPIF environment. Therefore, it is possible to construct a framework that facilitates access from outside, and takes advantage of the common management of various open service environments. An open service platform environment is expected to play an important role in transforming a network with simple connectivity services into a variety of new service markets, or into a service environment that can create added value.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.9 no.4
• /
• pp.39-45
• /
• 2009

With the rapid growth of recent wireless mobile computing application technology and handheld mobile terminal device development technology, one of the big issue in these fields is to design online games in wireless mobile ad hoc network environment. Online games in mobile computing environment have lots of constraints for developing online games because mobile terminals have many limitations such as low performance of processor, limited memory space, small bandwidth of wireless communication, and confined life of battery power. Therefore, most of mobile games are restrictive in the function of online and multi-play up to date. In this paper, the online MMORPG game, capable of multi-play with many other mobile users using mobile terminals in wireless mobile computing environment, is designed and implemented. Proposed mobile online game uses bluetooth to construct temporary wireless mobile ad hoc network with other mobile clients, and designed to carry out online MMORPG game with these clients. It also supports multi-play among them.

• Educational Technology International
• /
• v.13 no.1
• /
• pp.49-77
• /
• 2012

The development of mobile devices and network technology is changing the ways in which people communicate with one another. Mobile text message has emerged as one of the most frequently used form of communication, which also gave rise to various non-verbal texts such as emoticons. Nonetheless, the use of text messages has largely been denied in education because text messages often involve colloquial and non-verbal texts considered inappropriate or grammatically incorrect by the teacher. In efforts to provide a theoretical framework to better understand mobile e-text communication, this research compared the practical usages of non-verbal texts in the mobile e-learning environment. The study developed three types of text messages according to the degree of using non-verbal texts and their phraseology as instructors' messages, which were then distributed to 259 students via mobile text messaging. The perceptions of students were analyzed using a semantic differential scale and a questionnaire. The results showed clear differences in students' perceptions of non-verbal text and traditional text, and that optimally designed non-verbal texts turned out to encourage the students' interaction the most out of the three types of text messages. Following the discussion of the results, an expanded theoretical framework beyond Ong's concepts of orality and literacy is also suggested to understand the evolution of mobile e-text communication in education.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.5 no.3
• /
• pp.107-115
• /
• 2009

Traditionally, simulation method is used to test and evaluate the performance of communication protocol or functional elements for mobile communication service. In this paper, wireless network simulator is implemented using the C++ object-oriented programming language. This simulator can simulate wireless data services, like as ad-hoc networks, by considering the user's mobility. In this paper, the simulator includes network traffic model to reflect wireless data service and traffic source model to represent a user's mobility similar to real service environment and traffic characteristics can be reflected on the simulation, and also more accurate simulation results can be got through that. In addition, by using object-oriented techniques, new service feature or environment can be easily added or changed so that the developed mobile communication simulator can reflect the real service environment all the time. This simulator can be used in adjusting the characteristics of wireless data hosts following the mobility of the user, and also can be used in building new wireless ad-hoc network routing protocols.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2001.01a
• /
• pp.186-191
• /
• 2001

Mobile agent technologies are getting popular as means for accessing network resources efficiently. In order for mobile agents to be accepted as a reliable technology for applications such as e-commerce, a proper framework for mobile database should be established. In this paper, we first discuss weak points of current mobile computing systems that mostly result from the limitations of current mobile computing technology including frequent disconnection, limited battery capacity, low-bandwidth communication and reduced storage capacity. These weak points also have become the cause of transaction problem where mobile devices issue transactions. In order to eliminate this transaction problem in the mobile environment, we propose a mobile database framework, Proxyne, which is based on the proxy and SyncML.

• Journal of Korea Society of Industrial Information Systems
• /
• v.18 no.2
• /
• pp.59-69
• /
• 2013

By the end of 2012, there were 5.1 billion mobile communication subscribers in South Korea. The majority of subscriptions (97.3 percent) were for mobile phones, particularly smartphones. From 2010 to 2012, the number of mobile phone subscriptions increased 2,000 percent, growing from an initial subscriber base of 150 million. This paper explores the changing mobile communication landscape from a socio-technological perspective to understand the underlying drivers of change and their effects on the South Korean populace. A content analysis of 11,156 electronic newspaper articles mentioning mobile communication in South Korea and occurring between 2010 and 2012 was conducted. 5,119 keywords were extracted based on frequency statistics and further analyzed to determine the drivers of change. Based on this analysis, we conclude that South Korea's mobile communication environment is focused on rapid expansion of technology with minor consideration given to the social aspects of this change. This has resulted in several negative consequences and we urge for new policies by government and industry to address this gap.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.5
• /
• pp.125-129
• /
• 2016

This study has a purpose of development of mobile health monitoring system for measuring, saving and transmitting health signals by standardizing and encoding methods under the mobile environment. The system consists of a module for measuring the health signals with Bluetooth function, encoding equipment for encoding the measured health signals by a standardized encoding method so as to maintain mutual compatibility between devices, and a mobile system for saving and transmitting the encoding health signals. The proposed system was realized under the mobilet environment and has showed to be able to make good use.