• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.1
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• pp.735-742
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• 2009

National Geographic Institute recently has produced a national paper map by means of a computer aided editing system using a national digital map 2.0. However, the map generalization should be made due to the portrayal difference between the digital map and the paper one and the criterion of the map generalization should be determined by the visual image. The tolerance limit of the map generalization has to be decided based on human vision. For this purpose, this study attempts to measure the size of the building on various scale map and then analyze its result. As a consequence, this study shows us that the building size eligible for human vision should be over 0.4mm in the short side of building on the map. The tolerance limit of an isolated building, a reduced building and a densely built-up area for the map generalization is based on the criterion mentioned above.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.13 no.1
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• pp.77-83
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• 1995

This paper is concentrated on map generalization in digital environment for automated multi-scale map pro-duction using conventional hardcopy maps. Line generalization is urgently required process to prepare small scale digital map database when large scale map databases are available. This paper outlines a new approach to the line generalization when preparing small scale map on the basis of existing large scale distal map. Line generalizations are conducted based on zero-crossing algorithm using six sheets of 115,000 scale YEOSU area which produced by National Geographic Institute. The results are compared to Douglas-Peucker algorithm and manual method. The study gives full details of the data reduction rates and alternatives based on the proposed algorithm.

• Journal of the Korean association of regional geographers
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• v.20 no.3
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• pp.245-255
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• 2014

There is limitation to represent forms and internal process of topography if using simple symbols for geomorphic landscape in the cartography. One of the alternative method to find a solution to these problems is to use association symbol to imagine real landscapes through map reading. This study suggested making method of association symbols to describe geomorphic landscapes effectively. Landforms are not static objects but dynamic pedogenesis and morphogenesis one. It should be consider form, process, and material to make landform mapping, and also, make landform symbols by considering scalable changeability for point-polygon, line-polygon, point-line by scale. As a results, this study expected to help applications for geomorphology as well as environments, ecology, archaeology, and civil engineering etc.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.19 no.2
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• pp.173-181
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• 2001

It is very important to assess spatial data quality of a digital map produced through digital map generalization. In this study, as a aspect of spatial data quality maintenance, we examined the tolerate range of theoretical expectation accuracy and established the quality assessment standard in spatial data for the transformed digital map data do not act contrary to the digital map specifications and the digital map accuracy of the relational scale. And, transforming large scale digital map to small scale, if we reduce complexity through processes as simplification, smoothing, refinement and so on., the spatial position change may be always happened. thus, because it is very difficult to analyse the spatial accuracy of the transformed position, we used the buffering as assessment method of spatial accuracy in digital map generalization procedure. Although the tolerated range of generic positioning error for l/l, 000 and l/5, 000 scale is determined based on related law, because the algorithms adapted to each processing elements have different property each other, if we don't determine the suitable parameter and tolerance, we will not satisfy the result after generalization procedure with tolerated range of positioning error. The results of this study test which is about the parameters of each algorithm based on tolerated range showed that the parameter of the simplification algorithm and the positional accuracy are 0.2617 m, 0.4617 m respectively.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.25 no.4
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• pp.289-297
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• 2007

Normaly, the map generlization methode has been used for the making of small scale map using a large scale map. The object join methode is consumed of a lots of processing time and the manual process. The object Join technique used in the NGI based on the digital map ver. 1.0 have problems of poor Joining rate and a lots of processing time. This study has improved the object Join technique considering of the geometry and attribute information for the digital map ver. 2.0. Using improved technique increased joining rate of object and reduced the processing time.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1393-1405
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• 2020

UAV (Unmanned Aerial Vehicle) can acquire high-resolution images due to low-altitude flight, and it can be photographed at any time. Therefore, the UAV images can be updated at any time in map production. Due to these advantages, studies on the possibility of producing large-scale digital maps using UAV images are actively being conducted. Precise digital maps can be used as base data for digital twins or smart cites. For producing a precise digital map, precise sensor modeling using GCPs (Ground Control Points) must be preceded. In this study, geometric models of UAV images were established through a precision sensor modeling algorithm developed in house. Then, a digital map by stereo plotting was produced to evaluate the possibility of large-scale digital map. For this study, images and GCPs were acquired for Ganseok-dong, Incheon and Yeouido, Seoul. As a result of precision sensor modeling accuracy analysis, high accuracy was confirmed within 3 pixels of the average error of the checkpoints and 4 pixels of the RMSE was confirmed for the two study regions. As a result of the mapping accuracy analysis, it satisfied the 1:1,000 mapping accuracy announced by the NGII (National Geographic information Institute). Therefore, the precision sensor modeling technology suggested the possibility of producing a 1:1,000 large-scale digital map by UAV images.

• Journal of the Korean Geographical Society
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• v.40 no.1 s.106
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• pp.1-26
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• 2005

This paper is to classify old county-maps of Dongrae-bu(東萊府), Busan in late-Chosun dynasty and to analyze place names in maps comparatively. 26 maps covering Dongrae-bu were collected from the old county-map atlas(郡縣地圖帖) and Eupji(邑誌). By e comparative analysis of contents, those maps can be classified into four types. The first type(named 'Haedong-Jido(海東地圖)') included 7 county-maps in which information of military, and administrative contents are mainly mapped. The second type(named 'Yeongnam-do(嶺南地圖)') included 5 coon maps in which information about beacon routes and road systems were regarded as very important. The third type(named 'Grid-system map(方眼式地圖)') included 4 county-maps which were drawn as same scale with 20-ri(理) grids. The fourth type(named 'Local Count-map(地方郡懸地圖)') included 7 county maps which were drawn by local mappers. Comparative analysis of place names between those four types revealed that Grid-system maps were developed toward the large scale whole map of Korea in the 19th century.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.12
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• pp.1806-1814
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• 1993

Efficient speech coders using tree coding combined with harmonic scaling are designed at the rate of 4.8 kilobitts/sec (kbps). A time domain harmonic scaling algorithm (TDHS) is used to compress input speech by a factor of two. This process allows the tree coder have 1.5 bits/sample for 4.8 kbps in the case of a 6.4 kHz sampling rate. In the backward adaptive tree coder, there are three components of the code generator, including a hybrid adaptive quantizer, a short-term predictor and a pitch predictor. The robustness of the tree coder is achieved by carefully choosing the input of the short term predictor adaptation. Also, inclusion of a smoother in the pitch predictor improves the error performance of tree coder in the noisy channel. Subjectively, tree coding combined with TDHS provides good quality speech at 4.8 kbps.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12C
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• pp.1280-1287
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• 2006

We propose a modified stochastic gradient-based (MSGB) filter showing that the filter is the solution to an optimization problem. This paper analyzes the properties of the MSGB filter that corresponds to the nonlinear adaptive filter with additional update terms, parameterized by the variable scaling factor. The variably parameterized MSGB filter plays a role iii connecting the fixed parameterized MSGB filter and the null parameterized MSGB filter through variably scaling parameter. The stability regions and misadjustments are shown. A system identification is utilized to perform the computer simulation and demonstrate the improved performance feature of the MSGB filter.

• Proceedings of the KGS Conference
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• 2003.05a
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• pp.211-214
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• 2003

지도는 기호, 주기, 색상, 경위선, 축척 등과 같은 여러 요소들을 사용하여 지도 사용자들에게 다양한 지리적 사상들(geographic features)의 존재와 그들의 상관관계를 전달하는 일종의 의사소통 수단이다(황철수, 2002). 주기(label)는 $\ulcorner$지역, 인공물, 자연물의 고유명칭 및 고유명이 없는 것의 종류 또는 상태 등을 표시하는 설명 및 표고와 등고선수치 등을 문자 또는 숫자로서 표기하는 것1)$\lrcorner$, 즉 지도에 나타나는 사상들에 대해 설명하기 위해 입력되는 문자열을 의미하는 것으로 지도의 여러 가지 요소들 중에서도 가장 직접적이고 구체적으로 사상을 표현할 수 있는 요소이다. (중략)