• Title/Summary/Keyword: 시공간

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시공간 데이터를 위한 클러스터링 기법의 성능 비교

  • 강주영;이봉재;송재주;신진호;용환승
    • Proceedings of the Korean Information Science Society Conference
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    • pp.49-51
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    • 2004
  • 최근 GPS시스템, 감시 시스템, 기상 관측 시스템과 같은 다양한 응용 시스템으로부터 수집된 시공간 속성을 가진 데이터를 분석하고자 하는 시공간 데이터 마이닝에 대한 관심이 더욱 높아지고 있다. 기존의 시공간 데이터 마이닝에 대한 연구는 문자.숫자 데이터를 기반의 마이닝 기법을 그대로 적용하고 있기 때문에 데이터의 시공간 속성을 충분히 고려한 분석으로는 한계가 많은 것이 사실이다. 본 논문에서는 패턴 인식과 클러스터링 능력이 뛰어나다고 알려진 SOM을 기반으로 시공간 클러스터링 모듈을 개발하고, 개발된 모듈의 성능과 클러스터링 정확성에 대하여 K-means, 응집 계층 알고리즘(Average Linkage, Ward)과 비교함으로써 시공간 데이터 마이닝을 위한 각 알고리즘들의 성능을 분석하였다 또한 입력 데이터의 특성과 클러스터링 결과를 더욱 정확하게 나타내어 가시적인 분석을 도울 수 있도록 시공간 데이터 클러스터링을 위한 가시화 모듈을 개발하였다.

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Extension of Aggregate Functions for Spatiotemporal Data Analysis (데이타 분석을 위한 시공간 집계 함수의 확장)

  • Chi Jeong Hee;Shin Hyun Ho;Kim Sang Ho;Ryu Keun Ho
    • Journal of KIISE:Databases
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    • v.32 no.1
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    • pp.43-55
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    • 2005
  • Spatiotemporal databases support methods of recording and querying for spatiotemporal data to user by offering both spatial management and historical information on various types of objects in the real world. We can answer to the following query in real world: 'What is the average of volume of pesticide sprayed for cach farm land from April to August on 2001, within some query window' Such aggregation queries have both temporal and spatial constraint. However, previous works for aggregation are attached only to temporal aggregation or spatial aggregation. So they have problems that are difficult to apply for spatiotemporal data directly which have both spatial and temporal constraint. Therefore, in this paper, we propose spatiotemporal aggregate functions for analysis of spatiotemporal data which have spatiotemporal characteristic, such as stCOUNT, stSUM, stAVG, stMAX, stMIN. We also show that our proposal resulted in the convenience and improvement of query in application systems, and facility of analysis on spatiotemporal data which the previous temporal or spatial aggregate functions are not able to analyze, by applying to the estate management system. Then, we show the validity of our algorithm performance through the evaluation of spatiotemporal aggregate functions.

Design and Implementation of a Spatio-Temporal Middleware for Ubiquitous Environments (유비쿼터스 환경을 위한 시공간 미들웨어의 설계 및 구현)

  • Kim, Jeong-Joon;Jeong, Yeon-Jong;Kim, Dong-Oh;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • v.11 no.1
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    • pp.43-54
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    • 2009
  • As R&D(Research and Development) is going on actively to develop technologies for the ubiquitous computing environment, which Is the human-oriented future computing environment, GIS dealing with spatio-temporal data is emerging as a promising technology. This also increases the necessity of the middleware for providing services to give interoperability in various heterogeneous environments. The core technologies of the middleware are real-time processing technology of data streams coming unceasingly from positioning systems and data stream processing technology developed for non-spatio-temporal data. However, it has problems in processing queries on spatio-temporal data efficiently. Accordingly, this paper designed and implemented the spatio-temporal middleware that provides interoperability between a mobile spatio-temporal DBMS(DataBase Management System) and a server spatio-temporal MMDBMS(Main Memory DataBase Management System). The spatio-temporal middleware maintains interoperability among heterogeneous devices and guarantees data integrity in query processing through real-time processing of unceasing spatio-temporal data streams and two way synchronization of spatio-temporal DBMSs. In addition, it manages session for the connection of each spatio-temporal DBMS and manages resources for its stable operation. Finally, this paper proved the usability of the spatio-temporal middleware by applying it to a real-time position tracking system.

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A Study of Spatio-temporal Complex Event Processing System (시공간 복합 이벤트 처리 시스템에 대한 연구)

  • Kim, Tae-Gyu;Baek, Sung-Ha;Chung, Warn-Ill;Bae, Hae-Young
    • Proceedings of the Korea Information Processing Society Conference
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    • pp.83-86
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    • 2010
  • 본 논문에서는 시공간 데이터 스트림에서 관심 이벤트를 검출할 수 있고 복잡한 공간 패턴을 감지할 수 있는 시공간 복합 이벤트 처리 시스템을 제안한다. 제안 시스템은 이동 객체 및 정적 객체에서 발생하는 시공간 데이터 스트림에서 스트림 발생시각, 위치 정보와 같은 시공간 정보를 데이터베이스와의 조인을 통해 얻은 관련 속성 정보를 활용하여 이벤트를 검출할 수 있다. 또한, 시공간 정보가 포함된 복잡한 패턴을 처리하기 위해 공간 패턴 연산자를 사용하여 시공간 복합 이벤트를 처리할 수 있다.

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Performance Comparisons of Quasi-orthogonal Space-time Block Codes Concatenated with Turbo Codes (터보부호와 연접된 준직교 시공간 블록부호의 성능 비교)

  • 김현일;박효열;황금찬
    • Proceedings of the Korean Information Science Society Conference
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    • pp.121-123
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    • 2004
  • 시공간 블록부호는 송신단에서 여러 개의 안테나를 사용하여 무선 통신의 신뢰도를 높인다. 그런데 4개의 송신안테나를 사용하는 시공간 블록부호는 다이버시티 차수 4와 전송률 1을 동시에 얻을 수 없다. 직교 시공간 블록부호는 다이버시티 차수 4를 유지하지만 전송률에서 손해를 보는 반면, 준직교 시공간 블록부호는 다이버시티 이득에서 손해를 보면서 전송률 1을 유지한다. 본 논문에서는 준직교 시공간 블록부호의 복호기에서 최대 우도 복호 방법으로 비트별 연성결정값을 출력하고, 터보부호와 연접하여 다양한 전송률에서 직교 및 준직교 시공간 블록부호의 성능을 비교하였다.

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Development of a Spatio-Temporal Query Processing System for Mobile Devices (모바일 장치용 시공간 질의 처리 시스템의 개발)

  • Shin, In-Su;Yang, Hyeong-Sik;Kim, Joung-Joon;Han, Ki-Joon
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.2
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    • pp.81-91
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    • 2012
  • As the recent development of the ubiquitous computing environment, u-GIS is being highlighted as the core technology of the ubiquitous computing environment, and thereby, studies on spatio-temporal data are being actively conducted. In this u-GIS environment, it is still difficult for existing mobile devices to efficiently manage the massive spatio-temporal data of u-GIS that are increasing day by day. Therefore, this paper develops a spatio-temporal query processing system for mobile devices in order to solve the problem. The system provides various spatio-temporal operators to insert/delete/update/search spatio-temporal data and supports a query optimization function that uses a spatio-temporal index for the flash memory and a spatio-temporal histogram for guaranteeing query execution speed. Lastly, by applying the spatio-temporal query processing system developed in this paper to the virtual scenario, this paper has proved that the system can be utilized in various application fields necessary to process spatio-temporal data in the mobile environment.

Extension of OpenGIS Model for Four Dimensional Spatiotemporal Data (4차원 시공간 데이터를 위한 OpenGIS 모델의 확장)

  • Kim Sang Ho;Chi Jeong Hee;Ryu Keun Ho
    • The KIPS Transactions:PartD
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    • v.12D no.3
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    • pp.375-384
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    • 2005
  • Most of data objects in the real world have spatial and temporal information simultaneously. One of the objectives of spatiotemporal databases is to provide a very expressive framework for spatiotemporal database applications. The object oriented spatiotemporal model can manage spatiotemporal data efficiently because the model is able to store the complete history of any objects. Therefore, in order to handle the spatiotemporal data in object oriented fashion, we proposed a low dimensional spatiotemporal model in the object oriented fashion that extended dimensionally two dimensional spatial model of OpenGIS to fit into the real world information and to include temporal information. In order to proof the proposed model, we design a data provider component which consists of the data source, the session, the command, and the rowset component, and implement it. The proposed four dimensional spatiotemporal data model and provider in the object oriented fashion can be used to store, retrieve and manage the object oriented spatiotemporal data.

An Detection Process of Spatiotemporal Event in Active Rule (능동규칙에서 시공간 사건의 검출과정)

  • 이지영;신예호;오광진;윤성현;류근호
    • Proceedings of the Korean Information Science Society Conference
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    • pp.367-369
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    • 1999
  • 기존의 능동 데이터베이스 시스템에 관한 연구는 관계형 및 객체지향형 데이터베이스 시스템을 위주로 연구되어 왔다. 그런데 능동규칙이 다차원 공간상의 공간 객체 및 공간 객체의 시간 흐름에 따른 이력을 포함하는 시공간 데이터를 다루기 위해서는 능동규칙의 시공간 확장이 필요하다. 이에 이 논문은 시공간 능동규칙 연구의 일환으로서 시공간 사건을 정의하기 위한 사건 부분을 시공간에 대응하도록 확장하고 이의 검출 모델에 관해 연구한다.

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Design and Implementation of Update Propagation Technique for Update Spatio-Temporal Data in Mobile Environments (모바일 환경에서 갱신된 시공간 데이터의 변경전파 기법의 설계 및 구현)

  • Kim, Hong-Ki;Kim, Dogn-Hyun;Cho, Dae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.2
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    • pp.395-403
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    • 2011
  • Various studies were performed for providing the latest spatio-temporal information in mobile GIS Environments. The two-way synchronization scheme collects updated spatio-temporal data in the field and synchronizes with a server by using the wireless network. However, the other mobile terminals have to perform periodically synchronizes with a server. In this paper, we propose the update propagation scheme about spatio-temporal data collected from the mobile terminal. The update propagation scheme does considering various factors where an influence is in the update propagation. Therefore, it provides various update propagation policies according to each factors.

A Relational Spatiotemporal Database Query Language and Their Operation (관계형 시공간 데이터베이스 질의언어와 연산)

  • Kim, Dong-Ho;Ryu, Keun-Ho
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.10
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    • pp.2467-2478
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    • 1998
  • The spatiotemporal databases support historical informations as well as spatial managements for the objects in the real world, and can be efficiently used to various applications such as geographic information system, urban plan system, car navigation system. Although there are so far several pioneering works in spatioemporal data modeling, it is little to study on spatiotemporal query language. So in this paper, we at first survey a modeling technique that makes spatiotemporal objects into databases, and then show some sighificant functions supported by query language. Also we suggest a new spatiotemporal database query language, entitled as STQL, which make users to enable to manage efficient historical information as well as spatial management function on the basis of relational query language, SQL. Also the proposed STQL, shows their operationsl in spatiotemporal daabases.

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