• Title/Summary/Keyword: past query

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Data Stream Storing Techniques for Supporting Hybrid Query (하이브리드 질의를 위한 데이터 스트림 저장 기술)

  • Shin, Jae-Jyn;You, Byeong-Seob;Eo, Sang-Hun;Lee, Dong-Wook;Bae, Hae-Young
    • Journal of Korea Multimedia Society
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    • v.10 no.11
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    • pp.1384-1397
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    • 2007
  • This paper proposes fast storage techniques for hybrid query of data streams. DSMS(Data Stream Management System) have been researched for processing data streams that have busting income. To process hybrid query that retrieve both current incoming data streams and past data streams data streams have to be stored into disk. But due to fast input speed of data stream and memory and disk space limitation, the main research is not about querying to stored data streams but about querying to current incoming data streams. Proposed techniques of this paper use circular buffer for maximizing memory utility and for make non blocking insertion possible. Data in a disk is compressed to maximize the number of data in the disk. Through experiences, proposed technique show that bursting insertion is stored fast.

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A Hierarchical Bitmap-based Spatial Index for Efficient Spatial Query Processing on Air (무선환경에서 효과적인 공간질의 처리를 위한 계층적 비트맵 기반 공간 색인)

  • Song, Doo-Hee;Park, Kwang-Jin
    • Journal of Internet Computing and Services
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    • v.12 no.6
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    • pp.43-51
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    • 2011
  • The recent development of the technology for wireless mobile computing and applied technology for location-based services has made it possible to support query processing faster than that in the past. However, some technological limitations on hardware and software still exist. The most critical aspects of query processing are accuracy and speed. For improving the accuracy, it is required that detailed information on the data involved in query processing be saved. In this case, the amount of information on the data increases, which decreases the speed. On the other hand, for increasing the speed, it is necessary to reduce the broadcast cycle, which enables rapid data acquisition as desired. In this case, because of insufficient index information, the listen time for the client increases, which may cause unnecessary energy consumption. Therefore, a trade-off occurs between the accuracy and speed. This paper proposes a hierarchical bitmap-based spatial index (HBI) as a solution for the aforementioned problems. HBI describes an object with 0 and 1 on the Hilbert curve map. It reduces the broadcast cycle by decreasing the index size on the basis of bit information and tree structure. Therefore, it is able to shorten the listen time and query processing time. In addition, HBI enables the detection of the locations of all the objects so that it is possible selectively listen to a broadcast. A performance evaluation of the proposed technique demonstrates that it is excellent.

Estimation of Uncertain Past and Future Locations of Moving objects (이동 객체의 불확실한 과거 및 미래의 위치 추정)

  • 안윤애;류근호
    • Journal of KIISE:Databases
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    • v.29 no.6
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    • pp.441-452
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    • 2002
  • If continuous moving objects are managed by conventional database, it is not possible for them to store all position information changed over time in the database. Therefore, a time period of regular rate is determined and position information of moving objects are discretely stored in the system for every time period. However, if continuous moving objects are managed as discrete model, we will have problems which cannot properly answer to the query about uncertain past or future position information. To solve this problem, in this paper, we propose the method and algorithm which use the history information stored in the same database, to estimate the past or future location of moving objects. The cubic spline interpolation is used to estimate the past location and the mean movement value of the history information is used to predict the future location of moving objects. Finally, from the location estimation experimentation of using virtual trajectory and location sample, we proved that the proposed cubic spline function has less error than the linear function.

A Study on Spatial-temporal indexing for querying current and past positions (현재와 과거 위치 질의를 위한 시공간 색인에 관한 연구)

  • Jun, Bong-Gi
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.6
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    • pp.1250-1256
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    • 2004
  • The movement of continuously changing positions should be stored and indexed for querying current and past positions. A simple extension of the original R-tree to add time as another dimension, called 3D R-tree, does not handle current position queries and does not address the problem of low space utilization due to high overlap of index nodes. In this paper, 1 propose the dynamic splitting policy for improving the 3D R-tree in order to improve space utilization of split nodes. 1 also extend the original 3D R-tree by introducing a new tagged index structure for being able to query the current and past positions of moving objects. 1 found out that my extension of the original R-tree, called the tagged dynamic 3DR-tree, outperforms both the 3D R-tree and 75-tree when querying current and past position.

Novel Directions in Adjuvant Chemotherapy for Early Stage Epithelial Ovarian Cancer

  • Sakarya, Derya Kilic;Yetimalar, M Hakan;Ozbasar, Demir
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4157-4160
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    • 2015
  • Treatment of early stage ovarian cancer remains controversial despite advances in chemotherapeutic options. Over the past 30 years, molecular and clinicopathologic studies accelerated and treatment of ovarian cancer has undoubtedly improved although there is a debate as to whether this impacts outcome or not. More recently, the introduction of targeted therapy started a new era. Probably it is because early stage disease comprises a small portion of the epithelial ovarian cancer, studies have mostly ignored this group and still there is no clear consensus regarding systemic treatment of early-stage lesions. However this group of patients has the best chance of cure. In this review, we focus on current developments in the treatment of early stage ovarian cancer and query the options.

The Development for Change Detection Technique in the Remotely Sensed Images by GIS (GIS를 이용한 원격탐사영상의 변화탐지기법 개발)

  • 양인태;한성만;박재국;천기선
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2003.04a
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    • pp.397-408
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    • 2003
  • The information about land use presents future development and vision being the basis of nation development; therefore, it is necessary to more active research that can detect wide land use and changes for the information and efficient management about land use. In this study, we wished to analyze effectively land use changes to Ansan city that is fast changing land use by the latest national land development and urbanization. this study executed land-cover classification using 4 year's Landsat TM images including Ansan city, and efficiently could manage the result of land-cover changes through Arc/Info GRID analysis. Especially, by using change detection system that is developed in this research, we could variously detect land-cover changes, and query and search easily past land-cover changes of pixels that correspond to specific region.

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Anatomy of Current Issues on Content-Based Image Retrieval (내용기반 영상검색 시스템의 분석 및 발전 방안)

  • Singh, Kulwinder;Ma, Ming;Park, DongWon;An, Syungog
    • The Journal of Korean Association of Computer Education
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    • v.6 no.4
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    • pp.31-36
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    • 2003
  • In the past few years, enormous improvements have been obtained in the field of content-based image retrieval (CBIR). This paper presents a comprehensive survey on the current CBIR systems and some of their challenging technical aspects, which stand as an obstacle on its way to become successful. Furthermore, we have focused on the current state of semantic image retrieval and also we have suggested future promising directions for further research.

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The Study on Dynamic Query Visualization of Digital Data - Focusing on Developing Element, Expression and Interface - (디지털 데이터의 동적 질의형 시각화에 관한 연구 -개발 요소, 표현, 인터페이스 중심으로-)

  • 최홍석;김성곤
    • Archives of design research
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    • v.17 no.2
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    • pp.437-450
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    • 2004
  • Advancement of the media it will be able to express the development and information of computer system causes a problem, how to get the information from plenty of digital data. It needs to the research that provides efficient interface to the user and presents the information visualization standard to the author Consequently, From this paper it investigated analysis of the dynamic diagram and the computer software it led development process of information visualization and result of development outcome. Important developing forms of Information visualization are include Element, Expression, Interface. For developing information visualization model, First, Find the element from many kind of media, include graphic. Second, Find form of the expression from past the diagram which comes to be used plentifully. Last, To get appropriate result it applies the interface, necessary from the interface component which is various uses from computer program. like this, on this paper presents about important three visualization developing forms with detail examples.

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Selectivity Estimation for Multidimensional Sequence Data in Spatio-Temporal Databases (시공간 데이타베이스에서 다차원 시퀀스 데이타의 선택도추정)

  • Shin, Byoung-Cheol;Lee, Jong-Yun
    • Journal of KIISE:Databases
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    • v.34 no.1
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    • pp.84-97
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    • 2007
  • Selectivity estimation techniques in query optimization have been used in commercial databases and histograms are popularly used for the selectivity estimation. Recently, the techniques for spatio-temporal databases have been restricted to existing temporal and spatial databases. In addition, the selectivity estimation techniques focused on time-series data such as moving objects. It is also impossible to estimate selectivity for range queries with a time interval. Therefore, we construct two histograms, CMH (current multidimensional histogram) and PMH (past multidimensional histogram), to estimate the selectivity of multidimensional sequence data in spatio-temporal databases and propose effective selectivity estimation methods using the histograms. Furthermore, we solve a problem about the range query using our proposed histograms. We evaluated the effectiveness of histograms for range queries with a time interval through various experimental results.

A Moving Object Management System for Location Based Service (위치기반서비스를 위한 이동 객체 관리 시스템)

  • 안윤애
    • Journal of the Korea Computer Industry Society
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    • v.4 no.12
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    • pp.986-998
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    • 2003
  • A moving object management system manages spatiotemporal data o( moving objects which change their location continuously over time such as people, animals, cars, cellular phones, and so on. This system can be applied to location based services such as vehicle tracking systems, digital battlefields, and animal habitat management. The existing systems neither suggest location estimation of the moving objects nor handle the loss data of the moving objects in real-time environment. Thus the existing systems have problems that they give the uncertain results of the query processing to the user query. In this paper, we design a new moving object management system. The proposed system processes the past and future location information of the moving objects by the location change function. Also we propose a location triggering method, which supplements loss of the location data of the mobile objects in real-time environment. Finally, we implement and apply the proposed system to a vehicle tracking system based on PDA. Thus we ascertain that the proposed system can be applied to the location based system.

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