• 한국컴퓨터정보학회논문지
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• 제7권4호
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• pp.16-23
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• 2002

최근 컴퓨터의 대용량화 및 고성능화에 따라 GIS에 근거한 다양한 형태의 연구 및 응용 시스템이 개발되고 있다. 또한, 점차적으로 PDA, HPC 등과 같은 Mobile 장치와 GPS와 같은 위치 추적 기술이 발전함에 따라 개인의 위치에 근거한 다양한 서비스가 제공되어지고 있다 이러한 Mobile GIS에서는 처리 능력이 낮은 Mobile 장치의 특성을 고려한 Mobile GIS를 위한 클라이언트의 개발이 필요하다. 이를 위하여, 본 연구에서는 Mobile GIS를 위한 클라이언트 인터페이스를 설계 및 구현하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권9호
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• pp.4044-4062
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• 2016

We investigate the optimization of energy consumption in Mobile Cloud environment in this paper. In order to optimize the energy consumed by the CPUs in mobile devices, we put forward using the asymptotic time complexity (ATC) method to distinguish the computational complexities of the applications when they are executed in mobile devices. We propose a multi-scale scheme to quantize the channel gain and provide an improved dynamic transmission scheduling algorithm when offloading the applications to the cloud center, which has been proved to be helpful for reducing the mobile devices energy consumption. We give the energy estimation methods in both mobile execution model and cloud execution model. The numerical results suggest that energy consumed by the mobile devices can be remarkably saved with our proposed multi-scale scheme. Moreover, the results can be used as a guideline for the mobile devices to choose whether executing the application locally or offloading it to the cloud center.

• 한국생산제조학회지
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• 제23권4호
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• pp.374-379
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• 2014

Mobile robots with omni-directional wheels can generate instant omni-directional motion without requiring extra space to change the direction of the body. Therefore, they are capable of moving in an arbitrary direction under any orientation even in narrow aisles or tight areas. In this research, an omni-directional mobile robot based on Mecanum wheels was developed to achieve omni-directionality. A CompactRIO embedded real-time controller and C series motion and I/O modules were employed in the control system design. Ultrasonic sensors installed on the front and lateral sides were utilized to measure the distance between the mobile robot and the side wall of a workspace. Through intensive experiments, a performance evaluation of the mobile robot was conducted to confirm its feasibility for industrial purposes. Mobility, omni-directionality, climbing capacity, and tracking performance of a squared trajectory were selected as performance indices to assess the omni-directional mobile robot.

• Educational Technology International
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• 제13권1호
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• pp.49-77
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• 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.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.414-418
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• 2003

VoIP는 voice와 data를 packet 형태로 통합하여 실시간으로 전송하는 기술이다. 최근 VoIP는 voice와 data를 통합하는 핵심 기술로 발전하고 있다. VoIP 기술 중에서 SIP는 VoIP에서 사용하는 H.323 처럼 real time Call 서비스를 위한 signaling protocol이다. 하지만 mobile user를 고려할 때 VoIP는 Mobile IP와 같은 기술과 결합이 절대적으로 필요하다. Mobile IP는 Mobile host가 인터넷상에서 임의의 위치에 접속하더라도 자신의 address로 transport되는 packet을 수신 할 수 있도록 IP 프로토콜을 확장한 기술이다. VoIP Network에서 Mobile service를 위해 해결해야 할 중요한 과제는 Delay 개선이다. 특히, VoIP 서비스가 Mobile IP와 결합할 경우 Delay 때문에 optimal service를 지원하지 못할 수 있다. This paper에서는 지금까지 연구된 방법과는 달리 SIP를 이용하여 Delay를 개선하였다. 본 연구결과는 현재 진행중인 IP 패킷을 이용한 wired/wireless Integrated service에 활용할 수 있도록 하였다.

• Journal of Information Technology Applications and Management
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• 제27권5호
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• pp.49-68
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• 2020

The Push-Pull-Mooring (PPM) model employ to explore the factors that affect the switching intention of mobile game players by analyzing the online survey data of 240 mobile game players in China. From the perspective of PPM model, Dissatisfaction with the current mobile game can promote players to leave the current mobile game, and other more attractive mobile games can pull players out of the current mobile game. As a mooring factor, habit can affect players' switching decisions. Players who have formed strong habits in current mobile games are more likely to resist or ignore the attractiveness of other mobile games and stay in the current mobile games rather than migrate to other mobile games. Another result shows that the more dissatisfied with the current mobile game, the higher the quality of alternative (relative challenge) mobile game, and the lower the investment size in the current mobile game, the more reluctant the players are to continue to maintain the relationship with the current mobile game. The higher the player's commitment to the current mobile game, the more likely it is to maintain the relationship with the current mobile game. The empirical results show that the framework of this study is highly consistent with the results of PPM model, and confirming that they can well apply to mobile game situations.

• 한국IT서비스학회지
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• 제11권2호
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• pp.339-353
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• 2012

Mobile communication technology is advancing forward to deliver more connected devices and richer content and applications. The number of subscriptions continues to grow along with an explosive increase in the mobile data traffic demand. Thereby, it creates a significant network capacity shortage concerns for mobile network operators. In order to address this problem, it is essential to increase the network capacity at a low additional cost. The device-to-device (D2D) communication based proximity service is believed to have a promising future mobile communication technology that is capable to create new mobile service opportunities and offload traffic to the eNB. In addition, it is also required to develop new mobile communication services and its business models not only to accommodate the increasing mobile traffic demand but also to foster profitability of mobile business service providers such as the network providers, contents providers and platform providers. In this article, we first analyze current mobile business eco-system in the context of CPNT based value chain. Then, propose service development framework and business model creation methodologies for the device-to-device communication based services in the beyond LTE/LTE-Advanced systems.

• 한국정보시스템학회지:정보시스템연구
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• 제17권3호
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• pp.153-174
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• 2008

Mobile commerce is defined as any direct or indirect transaction conducted and facilitated through a wireless telecommunication network such as payment, ticketing, auction and mobile banking. Despite the importance of mobile commerce, there have not been so many academic studies on the unique characteristics of mobile commerce environments. In this study, our research model is developed based on TAM(Technology Acceptance Model) to investigate the user's technology acceptance process in mobile commerce environment. The factors, such as ubiquity, compatibility, perceived usefulness, perceived ease of use, cost, security, attitude and behavior intention for mobile commerce were selected from pier study in information systems area. The data for empirical analysis of the research model is collected online-questionnaire of 167 mobile commerce users in South Korea. The hypotheses were analyzed using SPSS 15.0 and AMOS 7.0. The results of our study show that: (1) compatibility, perceived usefulness and security had influences on the attitude whereas perceived ease of use and cost did not have any significant impact on the attitude, (2) compatibility influenced perceived usefulness whereas perceived ease of use did not, and finally (3) ubiquity, perceived usefulness and attitude had considerable influences on intention for mobile commerce. Therefore, practitioners should focus on enhancing security, quality of contents and services as well as offering what mobile commerce users want. The results of this study may useful for academicians and practitioners alike.

• 융합신호처리학회논문지
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• 제11권4호
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• pp.332-337
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• 2010

본 논문에서는 로봇기술(Robot Technology, RT)과 정보기술(Information Technology, IT)의 핵심 인 휴대폰을 활용한 RITS(RT&IT System) 융합기술을 이용하여 로봇제어 및 원격감시를 수행하는 G-Robot의 프레임웍을 설계하고 구현하였다. 구현된 시스템에서 로봇에 장착된 휴대폰은 로봇을 제어하는데 활용할 뿐만 아니라 사용자의 휴대폰으로 영상정보를 전송한다. 사용자는 휴대폰을 활용하여 로봇의 주변지역을 감시하고 로봇의 움직임을 제어한다. 뿐만 아니라, 미리 설정된 상황이 발생했을 경우, 휴대폰이 합체된 로봇은 사용자의 휴대폰으로 데이터를 전송한다. 실험결과, 3세대 이동통신이 가능한 지역에서 휴대폰을 이용하여 실시간으로 로봇을 제어하였고, 로봇의 주변 환경을 감시 할 수 있었다. 또한 시야에서 관찰되는 영역에 로봇 있을 경우 휴대폰 대신 블루투스를 이용하여 실시간으로 로봇을 제어할 수 있었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.145-148
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• 2011

As a futuristic construction model, building information model(BIM) based project management system(PMIS) and mobile PMIS have been showing visible sign. However, researches on the 3D BIM based PMIS using mobile device are hard to find, result from limitation of mobile device application(slow speed at huge BIM file, display size, and etc.) and undefined standard of business processes. Therefore, this research aims at studying feasibility of mobile BIM PMIS based on cloud computing as a business model. In case of applying mobile BIM PMIS, 3D drawings and integrated building informations are possible on mobile devices in real time. it would support increasing the productivity of project participants as designer, engineer, supervisor, and etc. Globally, BIM based PMIS and Mobile BIM system, cloud computing based mobile BIM simulator are in the concept or experimental phase, therefore it is possible to secure global leading technology of IT and construction merger in the mobile BIM.