• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.619-626
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• 2008

In this paper, we proposed a RSS based cooperative localization algorithm using VRN for wireless sensor networks, which can estimate the BN position. The proposed localization system monitoring all nodes estimates a position of BN, and calculates an intersection area with cooperative localization. From the results, we confirm that BN intersection area is reduced as the number of RN is increased. In addition, the fewer RN exists, the more iteration needs at least 4 times. Moreover, the propose algorithm using 4 RNs is improved 71.6% estimation performance than conventional method. Therefore, the cooperative localization algorithm with VRN provides higher localization accuracy than RSS based conventional method.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.64-75
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• 2018

With the development of location-aware technologies and the activation of smart phones, location based social networks(LBSN) have been activated to allow people to easily share their location. In particular, studies on recommending the location of user interests by using the user check-in function in LBSN have been actively conducted. In this paper, we propose a location recommendation scheme considering time and user activities in LBSN. The proposed scheme considers user preference changes over time, local experts, and user interest in rare places. In other words, it uses the check-in history over time and distinguishes the user activity area to identify local experts. It also considers a rare place to give a weight to the user preferred place. It is shown through various performance evaluations that the proposed scheme outperforms the existing schemes.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.3 no.1
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• pp.5-14
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• 2004

"언제, 어디에서, 어떤 형태의 접속"도 가능하게 하는 유비쿼터스 네트워크 환경의 실현을 위해 음성, 데이터의 통합은 우선 지원되어야 할 애플리케이션이다. 블루투스는 음성, 데이터의 동시 처리가 가능한 무선 개인 영역 네트워크(WPAN: Wireless Personal Area Network) 표준이다. 저가, 저전력의 무선 통신을 기반으로 휴대폰, 무전 전화기(Cordless Telephone) 의 음성 통화와 노트북, PDA 등의 정보기기의 인터넷 접속을 가능하게 한다. 본 논문에서는 블루투스의 음성, 데이터 통합처리를 구현한 블루투스 액세스 포인트(Access Point)에 대해 기술한다. 근거리 무선 데이터 통신과 유실 네트워크의 연결을 이루어 노트북, PDA 등 단말기의 인터넷 동시 접속을 지원하며 블루투스 폰의 VoIP 통화를 구현하였다. 개발 완료된 시스템의 테스트 결과 다양한 벤더들의 제품들과 호환성을 이루어 표준안을 만족하였으며 성능 면에서 역시 규격에서 제시한 최대치에 근접한 매우 우수함을 나타내었다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2016.01a
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• pp.69-70
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• 2016

ZigBee는 전력소모가 적고 근거리통신방식을 사용하며 저비용인 장점을 가지는 개인 영역 네트워크 (PAN)이다. ZigBee가 산업과 헬스케어 등의 여러 애플리케이션에서 많이 사용되면서, 최근 ZigBee에서의 보안이 중요한 문제로 다루어졌다. 본 논문에서는 ZigBee 네트워크에서의 키 관리 기법을 조사하고 보안능력 및 성능을 분석한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.05a
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• pp.117-120
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• 2021

지능형 교통 시스템의 주요 인프라 중 하나인 VANET 은 차량과 인프라 간의 통신을 통해 교통을 예측함으로써 도로 상에서의 안전을 보장한다. VANET 은 모든 노드가 네트워크에 가입할 수 있는 개방형 네트워크이기 때문에 개인 정보 보호가 주된 관심사이다. 분산형 신뢰 관리 시스템은 차량 네트워크에서 수신된 메시지가 신뢰할 수 있는 지에 대한 여부를 결정함으로써, 악의적인 공격자로부터 차량을 지킬 수 있다. 분산형 k-익명성 체계와 블록체인을 결합한 신뢰 관리 시스템은 주변 차량들과 협력하여 익명의 은폐 영역을 구축한다. 본 논문에서는 블록체인을 적용한 분산형 신뢰 관리 시스템을 통해 차량의 위치 정보를 보호하는 최근 연구들을 살펴본 뒤에 향후 발전 방향에 대해 논하도록 하겠다.

• Proceedings of the Korea Multimedia Society Conference
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• 2000.04a
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• pp.111-116
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• 2000

컴퓨터네트워크를 통한 정보의 이동이 빈번한 오늘날, 중요 정보를 지키는 정보 보호 기술의 요구는 점차 늘어나고 있다. 이에 따라, 통신망 상의 프라이버시 보호, 기밀성, 무결성 같은 개인정보보호를 위해서 필수적인 암호학적 도구로 디지털 서명이 이용되고 있다. 본 논문에서는 이산대수 문제의 어려움에 기반하여, 디지털 서명대상을 2명에서 n명으로 확대한 다중서명 기법에 서명자 전원의 동의 없이는 서명을 검증할 수 없는 부정할 수 없는 서명의 기능을 부여한다. 이는 전자, 선거, 전자 현금 등 보다 복잡하고 민감한 사회적 영역에 적용될 수 있을 것이다.

• Information and Communications Magazine
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• v.32 no.10
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• pp.65-70
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• 2015

클라우드 컴퓨팅은 IT 자원(스토리지, 서버, 소프트웨어, 네트워크 등)을 인터넷 기술을 이용하여 서비스 형태로 제공하는 기술이다. 최근 클라우드 컴퓨팅 서비스의 영역이 지속적으로 확대되고 있으며 특히 사물인터넷 (Internet of Things) 등의 IT 기술 발전에 따라 가정, 의료 등에 클라우드 컴퓨팅을 접목하여 활용할 수 있는 방법이 활발히 연구되고 있다. 그러나 클라우드 컴퓨팅 서비스의 확산과 더불어 알려지지 않은 새로운 보안 위협, 클라우드 서비스 고객의 자기정보 통제권 상실, 개인정보 유출로 인해 발생하는 프라이버시 침해 또한 이슈가 되고 있다. 본 논문에서는 클라우드 보안을 위한 국제 표준화 기구와 해당 기구에서 추진 중인 국제 표준화 현황에 대해 살펴본다.

• Information Systems Review
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• v.22 no.2
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• pp.1-24
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• 2020

Cloud computing technology is expanding its services to individual consumers through storage and applications. This study aims to compare the predisposing factors that affect the perceived value and the intention to use between users who have used or experienced services and those who have never experienced services from the perspective of benefit and sacrifice based on the value-based acceptance model. The results showed that the sacrifice factor (perceived cost) had a significant effect on perceived value and perceived value had a significant effect on intention to use, but showed a difference in perceived benefit. Perceived usefulness, ubiquity, and network effects had significant impact for experienced users' perceived value, but for inexperienced users, ubiquity did not have significant impact. In addition, usefulness was the most significant factor for experienced users while network effect was the same for inexperienced users. The results of this study suggest that consumers' intention to use personal cloud service is evaluated as a benefit and sacrifice point and a new attempt to re-examine the role of previous experience.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.233-244
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• 2018

The purpose of this study was to improve awareness of network marketing business in South Korea, which takes a quite negative view of network marketing, to raise awareness of "starting up a business" as independent business owners, to assist them in building their own subjecthood in network business and entrepreneurial identity, and ultimately to give some suggestions on how to improve their self-directed entrepreneurial competency and the quality of their business management. To make an empirical analysis of 121 independent business owners of Korean native network marketing, the personal and background variables of the entrepreneurs were selected as independent variables, and entrepreneurship was selected as a mediator variable. The selected dependent variables were financial and non-financial business performances. A multiple regression analysis was conducted by inputting the variables. The findings of the study were as follows: It produced an effect of more financial performance when the innovation of the independent business owners of network marketing was better, and this innovation was possible to have only when they improved in entrepreneurial efficacy and locus of control. In contrast, only authenticity had an effect on boosting non-financial business performance among the factors of entrepreneurship. To have authenticity, it's necessary to strengthen achievement needs and awareness of locus of control among the personal characteristics of the independent business owners of network marketing. Among the factors of entrepreneurship, there was better authenticity when their personal networks were broader among their background characteristics. In addition, self-efficacy that was one of personal characteristics made a direct contribution to the enhancement of non-financial performance. As a result, independent business owners of network marketing are required to hold a strong belief in their own business, to be active in business activities and to have a high efficacy as spontaneous principal agents, and they also are required to have more adventurous, planned, active and propulsive achievement needs that enable them to attain the goals of their business and keep moving forward. Besides, they should foster their locus-of-control competency that is to control, endure and be responsible for a variety of phenomena or incidents that they face, and there will be better financial performance or non-financial performance only when they demonstrate their self-belief and confidence and when they have faith in and conviction about themselves. For independent business owners of network marketing, a consumer-centered thinking that entails authenticity and trustworthiness and touches the hearts of customers is a more effective marketing strategy than an egocentric thinking as sellers when they approach customers. And they are expected to make progress in terms of the quality of business management when their business attachment or enthusiasm is great enough to match their own efficacy with entrepreneurial identity or strike a balance between them.

• Journal of Digital Convergence
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• v.19 no.6
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• pp.225-232
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• 2021

Nowadays, opinion leaders influence the formation of public opinion on various issues in social network services. There has been a lack of research on the personal characteristics that inspire users to interact with opinion leaders and show intent to act. This paper verifies how the disposition of Facebook users' self-identity affects the quasi-social interaction with opinion leaders on Facebook and the intention to share information. As the perception and behavior of users on social media platforms differ depending on the type of issue, an online survey was conducted by classifying issue types into life culture and political sectors. Research found that personal identity had a significant positive effect on quasi-social interactions in the life culture and politics sectors, while group identity negatively affected quasi-social interactions. In addition, the intention to share information was confirmed to have a significant effect only in the life and culture areas of self-identity (social and group identity). Quasi-social interaction was confirmed to have a significant positive effect on all issue areas. The results of this study suggest the need to consider variations in opinion leader marketing strategies based on the types of self-identity of Facebook users in the future. In addition, the study shows that raising the level of quasi-social interaction at the corporate level without distinction of issue types can lead to effective results.