• Journal of Information Processing Systems
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• 제15권4호
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• pp.931-956
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• 2019

Documents contain information that can be used for various applications, such as question answering (QA) system, information retrieval (IR) system, and recommendation system. To use the information, it is necessary to develop a method of extracting such information from the documents written in a form of natural language. There are several kinds of the information (e.g., temporal information, spatial information, semantic role information), where different kinds of information will be extracted with different methods. In this paper, the existing studies about the methods of extracting the temporal information are reported and several related issues are discussed. The issues are about the task boundary of the temporal information extraction, the history of the annotation languages and shared tasks, the research issues, the applications using the temporal information, and evaluation metrics. Although the history of the tasks of temporal information extraction is not long, there have been many studies that tried various methods. This paper gives which approach is known to be the better way of extracting a particular part of the temporal information, and also provides a future research direction.

• 한국공간정보시스템학회 논문지
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• 제5권2호
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• pp.5-21
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• 2003

차세대 무선 인터넷의 킬러 어플리케이션으로 주목받고 있는 위치기반서비스는 시간에 따른 시공간 객체의 위치 및 영역 변화에 대한 분석 기능이 필수적이다. 시공간 데이터베이스 시스템은 대용량 시공간객체의 실시간 위치 정보를 효과적으로 저장하고 빠른 검색을 제공하는 시스템으로 그 필요성이 증가하고 있다. 또한, 시공간 데이터베이스 시스템에서는 시공간 객체의 비공간정보와 공간정보 및 시간정보를 통합 관리할 수 있고, 시간 정보와 관련된 연산을 효율적으로 처리할 수 있는 시공간 데이터모델에 대한 연구가 활발히 진행중이다. 본 논문에서는 시간 흐름에 따라 동적으로 변화하는 시공간 객체 정보들을 현재 시점의 상태와 과거의 변화 과정에 대한 정보를 효과적으로 관리할 수 있는 시공간 데이터 모델을 제안한다. 또한 제안하는 시공간 데이터 모델을 위한 다양한 시공간 연산을 설계하며, 시공간 데이터와 시공간 객체 연산의 무결성을 유지하기 위한 제약조건을 제시한다.

• 대한공간정보학회지
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• 제10권5호
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• pp.17-28
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• 2002

Time is regarded as an essential feature of land information enabling to track historical landmarks of land uses, ownerships, and taxations based on cadastral maps. Object-oriented temporal modeling helps to simulate and imitate time-varying cadastral data in a chronological and persistent manner. The aim of study is to analyze the role of temporal cadastre tracing footprints of foregoing events in response to various needs and demands associated with historical information of cadastral transactions. In this paper, temporal cadastral object model (TCOM) is proposed to delineate object version history. As an evidence of a new approach and conceptual idea for the importance of temporal cadastre, a part of spatio-temporal processes is illustrated to explain major changes of cadastral map. The feasibility and application of the approach is confirmed by proof-of-concept of temporal cadastre in land information management.

• Journal of Information Processing Systems
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• 제6권4호
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• pp.521-536
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• 2010

Spatio-temporal patterns extracted from historical trajectories of moving objects reveal important knowledge about movement behavior for high quality LBS services. Existing approaches transform trajectories into sequences of location symbols and derive frequent subsequences by applying conventional sequential pattern mining algorithms. However, spatio-temporal correlations may be lost due to the inappropriate approximations of spatial and temporal properties. In this paper, we address the problem of mining spatio-temporal patterns from trajectory data. The inefficient description of temporal information decreases the mining efficiency and the interpretability of the patterns. We provide a formal statement of efficient representation of spatio-temporal movements and propose a new approach to discover spatio-temporal patterns in trajectory data. The proposed method first finds meaningful spatio-temporal regions and extracts frequent spatio-temporal patterns based on a prefix-projection approach from the sequences of these regions. We experimentally analyze that the proposed method improves mining performance and derives more intuitive patterns.

• 한국컴퓨터정보학회논문지
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• 제22권12호
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• pp.35-48
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• 2017

Extracting temporal information from documents is becoming more important, because it can be used to various applications such as Question-Answering (QA) systems, Recommendation systems, or Information Retrieval (IR) systems. Most previous studies only focus on English documents, and they are not applicable to the other languages due to the inherent characteristics of languages. In this paper, we propose a new system, named ExoTime, designed to extract temporal information from Korean documents. The ExoTime adopts an external Knowledge Base (KB) in order to achieve better prediction performance, and it also applies a bagging method to the temporal relation prediction. We show that the effectiveness of the proposed approaches by empirical results using Korean TimeBank. The ExoTime system works as a part of ExoBrain that is an artificial intelligent QA system.

• Journal of information and communication convergence engineering
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• 제5권2호
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• pp.159-163
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• 2007

RFID applications are mostly associated with the timestamp when the events occur. For managing RFID data we need to design data modeling for RFID data to support monitoring and temporal queries. In this paper, we propose a temporal RFID data modeling to maintain the history of events and state changes and to monitor the states of RFID objects. This data modeling involves essential basic operations for RFID data to monitor the information of RFID objects and to support temporal queries. Filter operations can achieve better query performance and obtain efficient storage space usage. It is possible to adapt into different temporal business applications.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권3호
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• pp.149-157
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• 2001

In the video retrieval system, visual clues of still images and motion information of video are employed as feature vectors. We generate the temporal textures to express the motion information whose properties are simple expression, easy to compute. We make those temporal textures of wavelet coefficients to express motion information, M components. Then, temporal texture feature vectors are extracted using spatial texture feature vectors, i.e. spatial gray-level dependence. Also, motion amount and motion centroid are computed from temporal textures. Motion trajectories provide the most important information for expressing the motion property. In our modeling system, we can extract the main motion trajectory from the temporal textures.

• 한국언어정보학회지:언어와정보
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• 제6권1호
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• pp.91-103
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• 2002

The temporal structure of events on the discourse level has long been of great interest in both theoretical and computational linguistics. In this paper, we offer a unified approach to the temporal relationships related to a hierarchical discourse structure. We apply the method of pronoun resolution to the interpretation of tense. It is based on an analysis within the framework of the controlled information packaging theory. A unique aspect of our account is that temporal interpretation across discourse segments in global discourse is subject to the same principles as the interpretation of global anaphora, and that there is thus no need to postulate independent principles to account for the discourse behaviour of tense. In this way, we can neatly explain the general view that tense parallels the anaphoric nature of pronouns.

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권7호
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• pp.509-522
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• 2009

W3C 웹 온톨로지 워킹그룹에서는 시맨틱웹을 위한 온톨로지 언어를 위해서 OWL을 개발하였다. 하지만 OWL은 시간에 대한 의미체계를 표현할 수 없기 때문에 시간 정보에 기반한 추론을 수행할 수 없다. 실세계의 개체들은 시간의 흐름에 따라 변하고 어떤 사건의 발생으로 인해 새로운 사실들이 생겨나고 있기 때문에 만약 지식베이스에 존재하는 지식이 시간 정보를 가지지 않는다면 불완전하고 부정확 해질 수 밖에 없다. 따라서 본 논문에서는 시맨틱웹에서 시간 정보를 표현하고 추론할 수 있도록 OWL을 시간에 대한 의미체계를 가지도록 확장한 온톨로지 언어인 TL-OWL올 제안한다.

• 한국정보처리학회논문지
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• 제5권6호
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• pp.1418-1430
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• 1998

시간지원 데이터베이스는 유효시간과 거래시간을 통해 객체에 대한 효율적인 이력관리를 제공한다. 유효시간은 현실세계에서 객체에 발생한 시간을 의미하며, 거래시간은 객체가 데이터베이스에서 정의된 연산 뿐만 아니라 사용자 질의에 내포된 이력정보에 관련된 연산을 처리할 수 있도록 확장되어야 한다. 따라서 이 논문에서는 시간지원 질의언어인 TQuel(temporal query language)을 대상으로 하는 이전에 제안된 시간지원 질의 처리 시스템에 대하여 시간지원 구문분석과 시간지원 의미분석, 그리고 시간지원 코드 생성 및 시간지원 실행기 등의 기본적인 요소를 기반으로 거래시간 관리, 시간지원 집계, 시간지원 뷰, 그리고 시간지원 죠인 및 최적화 기능을 추가로 설계 구현하고, 그 처리과정을 예를 들어 설명한다.