• Title/Summary/Keyword: data map

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Assessment of Accuracy of IKONOS Image Map, Traditional Orthophoto Map and Conventional Line Map of Kathmandu Valley : A Pilot Study

  • Kayastha, D.M.;Chhatkuli, R.R.;Paudel, J.R.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.988-990
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    • 2003
  • IKONOS image mapping is being considered a possible replacement to the traditional mapping in many countries due to their ease of access to current data and their potential high resolution. Survey Department of His Majesty's Government completed traditional orthophoto mapping of all urban and semi-urban areas of the country. The 1:5000 monochrome orthophoto maps of Kathmandu Valley were completed in 2003. In 2002, as a test, production of a near natural colour Image Map at 1:5000 scale of a part of Kathmandu Valley based on IKONOS data was carried out. A conventional line map plotting of the same area at 1:5000 was also prepared. The objective of the pilot project was to assess the geometric accuracy and the information content of these maps. The details of the study and their results are underlined. The findings of the study helps to explain whether IKONOS image map can replace conventional orthophoto map at 1:5,000 for urban areas of Nepal like Kathmandu.

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Sort-Based Distributed Parallel Data Cube Computation Algorithm using MapReduce (맵리듀스를 이용한 정렬 기반의 데이터 큐브 분산 병렬 계산 알고리즘)

  • Lee, Suan;Kim, Jinho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.9
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    • pp.196-204
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    • 2012
  • Recently, many applications perform OLAP(On-Line Analytical Processing) over a very large volume of data. Multidimensional data cube is regarded as a core tool in OLAP analysis. This paper focuses on the method how to efficiently compute data cubes in parallel by using a popular parallel processing tool, MapReduce. We investigate efficient ways to implement PipeSort algorithm, a well-known data cube computation method, on the MapReduce framework. The PipeSort executes several (descendant) cuboids at the same time as a pipeline by scanning one (ancestor) cuboid once, which have the same sorting order. This paper proposed four ways implementing the pipeline of the PipeSort on the MapReduce framework which runs across 20 servers. Our experiments show that PipeMap-NoReduce algorithm outperforms the rest algorithms for high-dimensional data. On the contrary, Post-Pipe stands out above the others for low-dimensional data.

Knowledge Map Service based on Ontology of Nation R&D Information (국가R&D정보에 대한 온톨로지 기반 지식맵 서비스)

  • Kim, Sun-Tae;Lee, Won-Goo
    • Journal of Digital Convergence
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    • v.14 no.3
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    • pp.251-260
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    • 2016
  • Knowledge map is widely used to represent knowledge in many domains. This paper presents a method of integrating the national R&D data and assists of users to navigate the integrated data via using a knowledge map service. The knowledge map service is built by using a lightweight ontology modeling method. The national R&D data is integrated with the research project as its center, i.e., the other R&D data such as research papers, patent, and project reports are connected with the research project as its outputs. The lightweight ontology is used to represent the simple relationships between the integrated data such as project-outputs relationships, document-author relationships, and document-topic relationships. Knowledge map enables us to infer the further relationships such as co-author and co-topic relationships. To extract the relationships between the integrated data, a RDB-to-Triples transformer is implemented. Lastly, we show an experiment on R&D data integration using the lightweight ontology, triples generation, and visualization and navigation of the knowledge map.

Vector Map Data compression based on Douglas Peucker Simplification Algorithm and Bin Classification (Douglas Peucker 근사화 알고리즘과 빈 분류 기반 벡터 맵 데이터 압축)

  • Park, Jin-Hyeok;Jang, Bong Joo;Kwon, Oh Jun;Jeong, Jae-Jin;Lee, Suk-Hwan;Kwon, Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.18 no.3
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    • pp.298-311
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    • 2015
  • Vector data represents a map by its coordinate and Raster data represents a map by its pixel. Since these data types have very large data size, data compression procedure is a compulsory process. This paper compare the results from three different methodologies; GIS (Geographic Information System) vector map data compression using DP(Douglas-Peucker) Simplification algorithm, vector data compression based on Bin classification and the combination between two previous methods. The results shows that the combination between the two methods have the best performance among the three tested methods. The proposed method can achieve 4-9% compression ratio while the other methods show a lower performance.

A Study on the Underground Utilities Data Base by UTIC System (UTIC System을 이용한 지하매설물 자료기반 구축에 관한 연구)

  • 이재기;최석근;이재동;이현직
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.13 no.2
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    • pp.135-140
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    • 1995
  • As the expansion of metropolis has been going, the role of underground utilities has importantly increased. The existed data is difficulty to acquire accurate data and computerize it. In the construction site, Particularly, the map of existed underground utilities has included so much inaccurate data. This study suggestes that making terrain map and surveying if the position of underground utilities are simultaneously done, also this method improves data accuracy and makes the computerized map such as CAD easy match the map of established underground map. The excution of this study collectes data by surveying of terrain and under ground utilities. Through new data collection, we can plot and acquire the position of real under ground utilities and attribute data about them.

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The Developing Method of Map Outline Using Caricature Generation Algorism (캐리커처 생성 알고리즘을 이용한 지도 외형선 생성 방법)

  • Kim, Sung-Kon
    • Archives of design research
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    • v.20 no.3 s.71
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    • pp.345-354
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    • 2007
  • Sometimes characterized graphic map rather than realistic graphic map can help users to understand information more easily. This paper tried to reveal the relation between the methodology to create outline on the map using caricature automatic algorism and level of human cognition. Caricature algorism such as exaggeration transformation algorism, joint transformation algorism and simplification algorism were used to create outline on the map. In order to apply exaggeration transformation algorism and joint transformation algorism, the method to create average form of the object were developed. We survey how users recognize the similarity of the characterized map with the real map when realistic map is simplified by certain value of simplification rate and transformed into certain value of exaggeration rate or joint transformation rate. We also survey how users recognize the similarity differently according to the scale of the map. As a result of this study, the method to calculate the optimal data is developed for users to recognize caricatured map effectively by shifting scale. This data can be used as basic data, when map developers create outline of map with programming code on computer

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Fast Local Indoor Map Building Using a 2D Laser Range Finder (2차원 레이저 레이진 파이더를 이용한 빠른 로컬 실내 지도 제작)

  • Choi, Ung;Koh, Nak-Yong;Choi, Jeong-Sang
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.99-104
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    • 1999
  • This paper proposes an efficient method constructing a local map using the data of a scanning laser range finder. A laser range finder yields distance data of polar form, that is, distance data corresponding to every scanning directions. So, the data consists of directional angle and distance. We propose a new method to find a line fitting with a set of such data. The method uses Log-Hough Transformation. Usually, map building from these data requires some transformations between different coordinate systems. The new method alleviates such complication. Also, the method simplifies computation for line recognition and eliminates the slope quantization problems inherent in the classical Cartesian Hough transform method. To show the efficiency of the proposed method, it is applied to find a local map using the data from a laser range finder PLS(Proximity Laser Scanner, made by SICK).

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The Analysis of Positional Accuracy with Input/Output Instruments in Digital Mapping of National Base Map (국가기본도 수치지도제작 과정에서 입출력장비에 따른 위치정확도 분석)

  • 이현직;손덕재
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.16 no.2
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    • pp.291-297
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    • 1998
  • In order to accomplish the digital map production I/O devices should be used which are used for data input procedure to convert original paper map(hardcopy) data into computer compatible digital map data, and for the mapsheet output procedure of worked out data. For the input device, digitizer and scanner are most frequently used. Digitizer has possibility of direct production of digital data, and are mainly used for input procedure of partly plotted source map. In contrary, scanner is rather easy to operate the instrument, so that is widely used for the input procedure of original sheet map. In this study, to extract the input device characteristics, some kinds of digitizers and scanners were cheesed and used for the positional error analysis through the operational method and types of instruments. Also for the output device characteristics, some kinds of plotter and materials are used and compared to analyze the positional error through the instrumental types and output sheet materials.

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A Study on Tile Map Service of High Spatial Resolution Image Using Open Source GIS (Open Source GIS를 이용한 고해상도 영상의 Tile Map Service 시스템 구축에 관한 연구)

  • Jeong, Myeong-Hun;Suh, Yong-Cheol
    • Journal of Korean Society for Geospatial Information Science
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    • v.17 no.1
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    • pp.167-174
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    • 2009
  • A Tile Map Service is a regular map service that has been enhanced to serve maps very quickly using a cache of static images. The map cache is a directory that contains image tiles of a map extent at specific scale levels. Returning a tile from the cache takes the server much less time than drawing the map image on demand. Use of a Tile Map Service can dramatically improve the time that clients take to display complex base-maps. Using Tile Map Services thus eliminate the need to trade quality for performance. This study provides a way to construct Tile Map Service System using Open Source GIS. We used GDAL(Geospatial Data Abstraction Library) which is one of the Open Source GIS Softwares to make Tile Map Image and OpenLayers to publish Web Page. Moreover, We conducted a performance test on Tile Map System and Dynamic Map System and evaluated the results of it. As a result, the proposed method makes it easier to construct high performance Tile Map Service using Open Source GIS without commercial products.

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A Design for XMDR Search System Using the Meta-Topic Map (메타-토픽맵을 이용한 XMDR 검색 시스템 설계)

  • Heo, Uk;Hwang, Chi-Gon;Jung, Kye-Dong;Choi, Young-Keun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.8
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    • pp.1637-1646
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    • 2009
  • Recently many researchers have been studying various methods for data integration. Among the integration methods that the researchers have studied, there are a method using metadata repository, and Topic Map which identifies the relationships between the data. This study suggests Meta-Topic Map to create Topic Map about search keyword by applying metadata and Topic Map, and the XMDR as a way to connect Meta-Topic Map with metadata in the legacy system. Considering the semantic relationship of user's keyword in the legacy system, the Meta-Topic Map provides the Topic Map format and generates the Topic Map about user's keyword. The XMDR performs structural integration through solving the problem of heterogeneity among metadata in the legacy system. The suggested svides isproves the interoperability among existing Relational Database constructed in the legacy system and the search efficiency and is efficient in expanding the system.