• Proceedings of the Korean Information Science Society Conference
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• 2008.06d
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• pp.332-336
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• 2008

오늘날 보이지 않는 수많은 장치들과 소프트웨어들이 서로 연결되어 각각의 사용자들에게 편리한 서비스를 제공하는 유비쿼터스 환경에서 모바일 단말기는 유저와 서비스간의 매개체 역할을 한다. 하지만 자원이 제한적인 모바일 단말기의 특성상 사용 시에 많은 제약이 있다. 이러한 문제를 해결하기위해 가용한 주변의 장치 자원을 연결하여 사용할 수 있도록 표준 인터페이스를 제공하는 기술들이 있다. 하지만 동적으로 변화하는 사용자의 선호도 정보와 장치 자원 정보와 같은 프로파일 정보를 효율적으로 적용하지 못하여 사용자 맞춤형 디바이스를 제공하지 못하는 문제점이 있다. 본 논문에서는 유비쿼터스 환경에서 이러한 프로파일 정보를 효율적으로 적용하여 사용자 맞춤형 자원 공유 서비스를 제공하는 시스템을 제안한다.

• Journal of the Korea Society of Computer and Information
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• v.16 no.4
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• pp.159-168
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• 2011

As e-commerce and social media service evolves, studies on recommender systems advance, especially concerning the application of collective intelligence to personalized custom service. With the development of smartphones and mobile environment, studies on customized service are accelerated despite physical limitations of mobile devices. A typical example is combined with location-based services. In this study, we propose a recommender system using movie genre similarity and preferred genres. A profile of movie genre similarity is generated and designed to provide related service in mobile experimental environment before prototyping and testing with data from MovieLens.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.1-9
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• 2010

This paper introduces a difference between mobile Augmented Reality (AR) authoring and desktop AR authoring, and suggests an interface system that can be applied to in-situ authoring of AR contents on a mobile device. The mobile devices have enabled users to use the AR system anytime and anywhere. It is now necessary to create user's individualized context information using mobile devices on the spot. To author AR contents easily with mobile devices, we need to maximize the convenience of mobile systems, which have yet limitation. To do so, this paper suggests new interaction approaches that manage augmented contents using visual cues and other simple attribute settings. In addition, to solve the problem that users have to hold their mobile devices to track markers while authoring contents, this system enables users to author contents in environment based on captured images. This interface system also can make cooperation environment for more than one users to author contents. This paper verifies the usefulness of the proposed interface by user tests. The results of an analyzing users' comments show that the proposed interface is suitable for in-situ mobile authoring system.

• The Journal of Korean Association of Computer Education
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• v.11 no.5
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• pp.67-76
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• 2008

Grid computing has a large scale virtual computing environment that enables a collaborative processing through sharing resources of geographically distributed organizations. In recent year, the development of wireless networks and mobile devices enables mobile devices to consider as a resource of the grids. However, there are some problems such as low performance of processors, small capacity of storages, limited capacity of battery, and low bandwidth. In this paper, to overcome these limitations occurred in mobile grid environments, we proposed a proxy-based mobile grid system. Our proposed system enables mobile devices to play roles as a resource consumer and a resource provider and to collaborate with wired grids through a mobile router. Also, we propose an adaptive job scheduling scheme to cope with context changes of mobile devices and compare our scheduling scheme with other scheduling schemes using a simulation tool, SimGrid, to verify the validity of our job scheduling scheme.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.1011-1014
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• 2005

하나의 웹서비스가 이 와 연동하는 클라이언트와 1회 이상의 연동(interaction)을 필요로 할 경우, 웹서비스에서는 이를 명확히 정의하는 규약이 필요하게 되는데 이를 안무(choreography) 또는 대화(conversation)라 부르며, 총칭하여 협업 웹서비스 기술로 부른다. 최근 W3C는 웹서비스의 안무를 위한WS-CDL(Choreography Description Language)를 개발 중에 있으며, WS-CDL은 웹서비스들 간의 전체적인 안무 교환이나 메시지 교환을 정의 한다. 그러나, WS-CDL은 연결성 (connectivity)이 항상 보장되지 않는 모바일 환경이나 사용자가 이동하는 경우에 사용하기에는 비효율이 따른다. 본 논문에서는 WS-CDL개발 동향에 대 해서 살펴 보고, 가지고 있는 문제점을 보완하기 위한 방안을 제시한다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2014.01a
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• pp.305-306
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• 2014

본 논문은 모바일 기기인 스마트폰이 교육환경을 바꾸고 있는 현실에 착안하여 대학 수업에 필요한 몇 가지 방안을 제시하였다. 모바일 기기인 스마트폰은 휴대성과 신속성이 강하기 때문에 컴퓨터와 노트북이 갖는 불편한 점을 보완할 수 있다. 그렇기에 스마트폰은 교육적 활용도가 높다. 먼저 교수는 수업 전에 학생들이 카카오톡을 가입해서 활동할 수 있게 한다. 예컨대 단체 카톡방, 조별 카톡방을 운영해서 공지사항을 올리고 학생들과 소통해야 한다. 때로는 개별 카톡방을 운용하면서 학생들에게 필요한 정보와 상담을 제공할 수 있어야 한다. 또한 학생들은 주어진 과제를 수행하기 위해서 조별 카톡방을 적극 활용해야 한다. 이는 학생들이 조별 카톡방을 통해 과제를 수행하는 과정에서 발생하는 시간과 공간의 제약을 극복하게 해주기 때문이다.

• Journal of the Korean Institute of Intelligent Systems
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• v.25 no.6
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• pp.551-557
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• 2015

Synchronization methods for shared data need to be selected properly based on characteristics of data and applications. In this paper we suggest a new semantic synchronization method, semanticAppr, for non_transactional data in disconnected mode. Our approach reduces loss of works in cooperative environments by weakening constraint of serializability. In addition it reduces data transfer by sending operation log instead document itself.

• Journal of Information Technology and Architecture
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• v.10 no.2
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• pp.251-261
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• 2013

The appearance of various mobile Internet environment access to existing networks of mobile devices is easier to tell. In addition, mobile device users to use the wireless environment than a wired environment, user profile information is readily available features. Mobile devices have features that use alone. These characteristics of mobile devices to apply the personalization service is the best system. This paper proposes for mobile device users a personalized mobile music content recommendation service. This service propose to utilizes the user's access history information using time-weighting and collaborative filtering. Access history information can find out information of user interest. Using this information, consider the preference of music genre and time-weighted based on the recommendations makes the music. This method the problem of the traditional music recommendation system, point user's favorite music genre is changing over time do not consider that to solve the problem.

• Journal of Intelligence and Information Systems
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• v.12 no.2
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• pp.1-15
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• 2006

Currently the mobile web service is growing with a tremendous speed and mobile contents are spreading extensively. However, it is hard to search what the user wants because of some limitations of cellular phones. And the music is the most popular content, but many users experience frustrations to search their desired music. To solve these problems, this research proposes a hybrid recommendation system, MOBICORS-music (MOBIle COntents Recommender System for Music). Basically it follows the procedure of Collaborative Filtering (CF) system, but it uses Contents-Based (CB) data representation for neighborhood formation and recommendation of new music. Based on this data representation, MOBICORS-music solves the new item ramp-up problem and results better performance than existing CF systems. The procedure of MOBICORS-music is explained step by step with an illustrative example.

• Journal of Intelligence and Information Systems
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• v.15 no.1
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• pp.31-50
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• 2009

As the collected information which is static or dynamic is infinite in ubiquitous computing environments, information overload and invasion of privacy have been pressing issues in the recommendation service. In this study, we propose a recommendation service procedure through P2P, The P2P helps customer to obtain effective and secure product information because of communication among customers who have the similar preference about the products without connection to server. To evaluate the performance of the proposed recommendation service, we utilized real transaction and product data of the Korean mobile company which service character images. We developed a prototype recommender system and demonstrated that the proposed recommendation service makes an effect on recommending product in the ubiquitous environments. We expect that the information overload and invasion of privacy will be solved by the proposed recommendation procedure in ubiquitous environment.