• 한국컴퓨터정보학회논문지
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• 제16권12호
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• pp.205-214
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• 2011

본 논문에서는 아이폰의 GPS 기능과 Mapkit 프레임워크를 이용하여 사용자 간에 길 안내를 전달하는 모바일 어플리케이션을 제안한다. 아이폰의 GPS 기능은 사용자의 현재 위치를 얻을 수 있으며, Mapkit 프레임워크를 이용하여 지도에 각각의 위치를 표시 할 수 있다. 사용자는 목적지로 이동하면서 안내가 필요한 지점에서 어플리케이션을 터치하여 기록한다. 사용자는 목적지에 도착할 때까지 기록된 내용을 Google 지도를 통해 확인할 수 있으며, 목적지로 찾아올 다른 사용자에게 데이터를 전달한다. 데이터를 받은 다른 사용자는 카메라의 Overlay 위에 나타나는 다음 위치 아이콘으로 목표 위치를 보거나, 지도 화면을 확인 하면서 목적지로 가기 위해 이동해야 할 다음 위치를 쉽게 안내 받을 수 있다. 즉, 제안 어플리케이션은 사용자가 처음 가는 길 임에도 다른 사용자의 데이터를 전송 받아 손쉽게 길을 안내하는 유용한 기능을 제공한다.

• Journal of Information Processing Systems
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• 제7권1호
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• pp.121-136
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• 2011

With the rapid growth of GPS-enable Smartphones, the interest on using Location Based Services (LBSs) has increased significantly. The evolution in the functionalities provided by those smartphones has enabled them to accurately pinpoint the location of a user. Because location information is what all LBSs depend on to process user's request, it should be properly protected from attackers or malicious service providers (SP). Additionally, maintaining user's privacy and confidentiality are imperative challenges to be overcome. A possible solution for these challenges is to provide user anonymity, which means to ensure that a user initiating a request to the SP should be indistinguishable from a group of people by any adversary who had access to the request. Most of the proposals that maintain user's anonymity are based on location obfuscation. It mainly focuses on adjusting the resolution of the user's location information. In this paper, we present a new protocol that is focused on using cryptographic techniques to provide anonymity for LBSs users in the smartphone environment. This protocol makes use of a trusted third party called the Anonymity Server (AS) that ensures anonymous communication between the user and the service provider.

• 디지털산업정보학회논문지
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• 제10권3호
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• pp.151-159
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• 2014

Recently, spread of large amount Smartphones made users to download location-based service applications, which provided by application developers. These location-based service applications are convenient tool for users. Location-based service use technology to find location of user and provide information of user's location. Leakage of information of user's location and expose of privacy life raised new controversy. In this thesis, it will analyze relations of increase of Smartphone market, usage of Location-based service and severity of personal information leakage. Also, it will analyze examples of user's case of damage which caused by leakage personal information and find solutions to reduce damage of personal information leakage. In research, it will find cases of damage that cause by Location-based service. Also it will analyze and research cases of damage and present with graph and chart. In conclusion, to reduce and prevent from damage which caused by leakage personal information, it is important that users and application developers to realize danger of private and personal information leakage. Also, user's personal information must deal with cautiously and application developers have to research and develop the application with powerful security.

• 한국콘텐츠학회논문지
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• 제18권1호
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• pp.64-75
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• 2018

위치 인식 기술의 발전 및 스마트 디바이스 사용의 활성화로 인해 위치 기반 서비스과 소셜 네트워크를 결합하여 사용자에게 정보를 공유하는 위치 기반 소셜 네트워크(LBSN: Location Based Social Network)이 활성화되고 있다. 위치 기반 소셜 네트워크에서 사용자의 체크인 기능을 이용하여 사용자가 가 흥미있어 할 만한 장소를 추천하는 연구가 활발히 이루어지고 있다. 본 논문은 위치기반 소셜 네트워크에서 시간과 사용자 활동을 고려한 장소 추천 기법을 제안한다. 제안하는 기법은 기존 논문에서 고려하지 못한 시간에 따른 사용자의 선호도 변화와 지역의 전문가, 희귀한 장소에 대한 사용자의 관심을 고려한다. 다시 말해, 사용자의 선호도 변화를 고려하기 위해 시간에 따른 체크인 이력을 사용하고 지역의 전문가를 판별하기 위해 사용자 활동 영역을 구분한다. 그리고 사용자가 선호하는 장소에 가중치를 주기 위하여 희귀한 장소를 고려한다. 다양한 성능평가를 통해 제안하는 기법이 기존 기법에 비해 성능이 우수함을 보인다.

• 설비공학논문집
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• 제27권1호
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• pp.14-23
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• 2015

Although research and technology developments have recently increased to save lighting energy within buildings, such research and technology development are judged to be unsuitable for energy savings since they are limited in the sense that the application of the technology is fragmented. This study proposes a user and location awareness technology applied to dimming lighting control system and verified the effectiveness of energy savings by building a test bed. The results were as follows : 1) This study suggested a user and location awareness technology applied to dimming lighting control system. 2) The system shows 96.6% and 82.8% energy saving rates, respectively, on the basis of one user, compared to an on/off lighting control and the user and location awareness technology applied to on/off lighting control system. 3) The energy consumption of the user and location awareness technology applied to on/off lighting control system and the user and location awareness technology applied to dimming lighting control system increased to 96.6%, 88.3%, and 59.6% and 82.8%, 85.0%, 51.5%, respectively, on the basis of one, two, and three users, compared to the on/off lighting control system. This study confirmed the energy saving performance of the user and location awareness technology applied to the dimming lighting control system through performance evaluation. In this regard, further study needs to be undertaken to evaluate the performance at night time.

• 한국경영과학회지
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• 제33권3호
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• pp.43-58
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• 2008

In this paper, we have presented a dynamic, predictive location update scheme that takes into account each user's mobility patterns. A user's past movement history is used to create two-dimensional transition probability matrix which makes use of two directional consecutive location areas. A mobile terminal utilizes the transition probability to develop a predictive path which consists of several predictive nodes and then the location update is saved as long as a mobile user follows the predictive path. Using continuous-time Markov chain, cost functions of location update and paging are derived and it is shown that the number of predictive nodes can be determined optimally. To evaluate the proposed scheme, simulations are designed and the numerical analysis is carried out. The numerical analysis features user's mobility patterns and regularity, call arrival rates, and cost ratio of location update to paging. Results show that the proposed scheme gives lower total location management cost, compared to the other location update schemes.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제12권10호
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• pp.437-444
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• 2023

현재 위치기반서비스는 우리의 일상생활에서 중요한 역할을 하고 있으며, 이에 따라 위치 정보의 수집과 이용이 급속하게 증가하고 있다. 위치기반 서비스가 발전하면서 사용자가 느끼는 편의성은 증대되었지만, 프라이버시 침해에 대한 불안 역시 증가하였다. 이에 본 논문에서는 사용자의 위치 기록을 안전하게 기록하고 관리할 수 있는 애플리케이션을 설계 및 구현한다. Room DB를 이용하여 수집한 개인 위치 정보를 위치기반서비스 사업자의 서버가 아닌 사용자 기기의 로컬 데이터베이스에 저장한다. 또한 사용자가 원할 때 기록을 시작하고 종료할 수 있게 하여 위치 정보에 관한 개인정보 보호 측면을 강화한다. 사용자가 본인의 위치 정보를 스스로 제어함으로써 이동 경로 기록에 관한 사용자의 불안감을 감소시킬 수 있다.

• International Journal of Contents
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• 제5권2호
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• pp.59-63
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• 2009

Since it is hard to use GPS for tracking mobile user in indoor environments, much research has focused on techniques using existing wireless local area network infrastructure. Signal strength received at a fixed location is not constant, so fingerprinting approach which use pattern matching is popular. But this approach has to pay additional costs to determine user location. This paper proposes a new approach to find user's location efficiently using an index scheme. After analyzing characteristics of RF signals, the paper suggests the data processing method how the signal strength values for each of the access points are recorded in a radio map. To reduce computational cost during the location determination phase, multidimensional indexes for radio map with the important information which is the order of the strongest access points are used.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.311-315
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• 2009

The ubiquitous smart home is the home of future that takes advantage of context information from user and home environment and provides automatic home services for the user. User's location and motion are the most important contexts in the ubiquitous smart home. This paper presents a method positioning user's location using four cameras and some home context parameter together with user preferences provided. Some geometry math problems would be raised to figure out approximately which area is monitored by cameras. The moving object is detected within the image frames and then simulated in a 2D window to present visually where user is located and show his moving. The moving ways are statistically recorded and used for predicting user's future moving.

• 센서학회지
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• 제16권4호
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• pp.270-276
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• 2007

A location-aware system, which is capable to detect a user's whereabout in a region and provide real-time location information in outdoor environment is designed and fabricated, specifically using the GPS (global positioning system) as key technology in view of its stability and high precision in outdoor environment. Experiment is conducted to test this application in campus-based environment. Once GPS receiver detects specific location which is tagged with GPS coordinates, the system provides information relevant to that context and user can operate and react accordingly. Besides, this location-aware system is able to provide user with the route in order to get to a desired place by detecting the direction that the user is moving towards from his/her initial location. The mapping data is transferred via wireless LAN to PDA carried by the user as well as to the back-end system on real-time basis. The test result is analyzed and discussed to validate the effectiveness of using GPS in implementing this system and indicates future works that could be made to improve this prototype to be implemented in other applications, such as theme park, tourist attraction spot or recreational park.