• 한국멀티미디어학회논문지
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• 제10권12호
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• pp.1752-1761
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• 2007

Location-based services are a recent concept that integrates a mobile device's location with other information in order to provide added value to a user. Although Location-based Services provide users with comfortable information, it is a complex task to manage and share heterogeneous and numerous data in decentralized environments. In this paper, we propose the Semantic LBS Model as one of the solution to resolve the problem. The Semantic LBS Model is a LBS middleware model that includes an ontology-based data model for LBS POI information and its processing mechanism based on Semantic Web technologies. Our model enables POI information to be described and retrieved over various domain-specific ontologies based on our proposed POIDL ontology. This mechanism provide rich expressiveness, interoperability, flexibility in describing and using information about POls, and it can enhance POI retrieval services.

• Architectural research
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• 제12권2호
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• pp.15-22
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• 2010

Our prediction model is based on the development of "Semantic Location Model." It embodies geometrical and topological information which can increase the efficiency in prediction and make it easy to manipulate the prediction model. Data mining is being implemented to extract the inhabitant's location patterns generated day by day. As a result, the self-learning system will be able to semantically predict the inhabitant's location in advance. This context-aware system brings about the key component of the ubiquitous computing environment. First, we explain the semantic location model and data mining methods. Then the location prediction model for the ubiquitous computing system is described in details. Finally, the prototype system is introduced to demonstrate and evaluate our prediction model.

• 정보처리학회논문지A
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• 제14A권4호
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• pp.209-214
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• 2007

3차원 게임 프로그래밍에서 요구되는 가상환경 생성에 있어서 가상환경의 기능이 단순한 배경 제공의 기능 외에 실세계 환경과 직접적으로 관련되는 정보를 포함하는 것이 필요하다. 본 연구에서는 게임에서 실제 환경을 가시화한 가상환경에서 캐릭터가 진행할 때 가상환경에서의 지리적 위치를 알게 함과 동시에 환경과 관련된 정보를 실시간으로 제공하는 시스템을 구현한다. 이러한 기능은 가상환경이 특정 지역에서 고유한 정보를 보유할 수 있게 하고 환경의 조건에 따라 장면을 제어해갈 수 있는 점에서 시맨틱 가상 환경(Semantic Virtual Environment) 구현의 한 방법을 제공한다고 할 수 있다. 본 논문에서는 이러한 게임에서의 시맨틱 가상환경 구현을 목적으로 유비쿼터스 환경에서 위치기반 실시간 정보 입력을 가능하게 하는 시스템과 가상환경 내 특정 위치를 찾아 대화형으로 네비게이션을 제어할 수 있도록 해주는 방법에 대해 설명한다.

• 로봇학회논문지
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• 제12권3호
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• pp.249-257
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• 2017

This paper proposes a method to segment urban scenes semantically based on location prior information. Since major scene elements in urban environments such as roads, buildings, and vehicles are often located at specific locations, using the location prior information of these elements can improve the segmentation performance. The location priors are defined in special 2D coordinates, referred to as road-normal coordinates, which are perpendicular to the orientation of the road. With the help of depth information to each element, all the possible pixels in the image are projected into these coordinates and the learned prior information is applied to those pixels. The proposed location prior can be modeled by defining a unary potential of a conditional random field (CRF) as a sum of two sub-potentials: an appearance feature-based potential and a location potential. The proposed method was validated using publicly available KITTI dataset, which has urban images and corresponding 3D depth measurements.

• Journal of Computing Science and Engineering
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• 제2권2호
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• pp.137-160
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• 2008

The increasing availability of personal location data pushed by the widespread use of location-sensing technologies raises concerns with respect to the safeguard of location privacy. To address such concerns location privacy-preserving techniques are being investigated. An important area of application for such techniques is represented by Location Based Services (LBS). Many privacy-preserving techniques designed for LBS are based on the idea of forwarding to the LBS provider obfuscated locations, namely position information at low spatial resolution, in place of actual users' positions. Obfuscation techniques are generally based on the use of geometric methods. In this paper, we argue that such methods can lead to the disclosure of sensitive location information and thus to privacy leaks. We thus propose a novel method which takes into account the semantic context in which users are located. The original contribution of the paper is the introduction of a comprehensive framework consisting of a semantic-aware obfuscation model, a novel algorithm for the generation of obfuscated spaces for which we report results from an experimental evaluation and reference architecture.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2011년도 한국컴퓨터종합학술대회논문집 Vol.38 No.1(C)
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• pp.255-257
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• 2011

본 연구에서는 각종 웹사이트와 이메일을 통해 전달되는 회의공지에 포함된 회의장소를 나타내는 문자열로부터 실제 위치를 추정하는 시스템을 설계 및 구현하였다. 직접 구현한 NER과 Relation-type Classification 모듈을 사용하였으며, 장소에 대한 모델은 기존의 지리정보시스템들과의 상호 운용성을 위하여 OpenStreetMap[6]과 Geonames[7]의 데이터 구조를 참조하여 설계되었고, 실제 위치를 구하기 위하여 내부자원 외에도, 각종 오픈API들을 외부자원으로 활용하였다.

• 음성과학
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• 제10권3호
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• pp.187-209
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• 2003

In this paper, we examine if the lexical information of the verb and its noun object affects the pitch accent patterns of the verb phrase focus. Three types of verb-object combinations with different semantic weights are discussed: when the verbs have optional direct objects, when the objects have the greater semantic weight relative to verbs, and when the verbs and the objects have equal semantic weight. Argument-structure-based works note that the pitch accent location in a focused phrase is closely related to the argument structure and contextual information. For example, it has been argued that contextually new noun objects receive accent while given noun objects don't. Contrary to nouns, verbs can be accented or not in verb phrase focus regardless of whether they are given information or new information (Selkirk 1984, 1992). However, the production experiment in this paper shows that the accenting of verbs is not fully optional, but influenced by the lexical semantic information of the verbs. The accenting of noun objects with given information is possible and the deaccenting of new noun objects also occurs depending on the lexical information of the noun objects. The results demonstrate that in addition to argument structure and information by means of context sentences, the lexical semantic information of words influences the pitch accent location in focused phrase.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.2(A)
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• pp.50-51
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• 2010

• 한국컴퓨터정보학회논문지
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• 제18권3호
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• pp.47-57
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• 2013

최근 스마트폰의 발전에 따라서 많은 위치 기반 서비스가 활용되고 있으며, 위치 정보 노출로 인한 문제점이 사회적 이슈로 대두되고 있다. 기존의 잘 알려진 위치 정보 보호를 위한 공간 클로킹 기법은 사용자가 요청한 지역에서 위치 정보를 흐릿하게 처리하였다. 하지만 계속적으로 움직이는 이동 객체의 모든 지역을 클로킹하기에는 범위공간이 무수히 넓어지는 문제를 가진다. 따라서, 본 논문에서는 이동 객체 정보 보호를 위한 그리드 기반 시멘틱 클로킹 기법을 제안한다. 제안 기법은 시멘틱 클로킹을 위하여 EMD 갱신 스키마를 확장하고 이동 객체를 위한 대표 보호지역의 클로킹을 정의하였다. 성능 평가에서는 제안 기법이 기존 기법에 비해 처리 시간과 공간 범위에서 안전성과 효율성을 높였다. 이를 통해, 성공적으로 다양한 적으로부터 지속적으로 움직이는 객체의 위치 개인 정보를 보호하여 기존의 방법을 능가하는 성능을 보인다.

• Spatial Information Research
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• 제21권1호
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• pp.1-13
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• 2013

This paper describes a GIS framework for geo-semantic information retrieval in mobile computing environments. We built geographic ontologies of POI (point of interest) and weather information for use in the combination of semantic, spatial, and temporal functions in a fully integrated database. We also implemented a geo-semantic app for Android-based smartphones that can extract more appropriate POIs in terms of user contexts and geographic ontologies and can visualize the POIs using Google Maps API (application programming interface). The feasibility tests showed our geo-semantic app can provide pertinent POI information according to mobile user contexts such as location, time, schedule, and weather. We can discover a baking CVS (convenience store) in the test of bakery search and can find out a drive-in theater for a not rainy day, which are good examples of the geo-semantic query using semantic, spatial, and temporal functions. As future work, we should need ontology-based inference systems and the LOD (linked open data) of various ontologies for more advanced sharing of geographic knowledge.