• Journal of Korea Spatial Information System Society
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• v.6 no.2 s.12
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• pp.15-22
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• 2004

Map services for cellular phone have problem for implementation, which are the limitation of a screen size. To effectively represent map data on screen of celluar phone, it need a process which translate a detailed map data into less detailed data using map generalization, and it should manipulate zoom in out quickly by leveling the generalized data. However, current spatial indexing methods supporting map generalization do not support all map generalization operations. In this paper, We propose a leveled spatial indexing method, LMG-tree, supporting map generalization and presents the results of performance evaluation.

• 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.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.167-170
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• 2005

In the mobile environments for the vector map services, a map simplification work through the map generalization steps helps improve the readability of the map on a large scale. The generalization operations are various such as selection, aggregation, simplification, displacement, and so on, the formal operation algorithms have not been built yet. Because the algorithms require deep special knowledge and heuristic, which make it hard to automate the processes. This thesis proposes some map generalization algorithms specialized in mobile vector map services, based on previous works. We will show the detail to adapt the approaches on the mobile environment, to display complex spatial objects efficiently on the mobile devices which have restriction on the resources

• Communications of Mathematical Education
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• v.30 no.1
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• pp.23-46
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• 2016

This study is aimed to implement a preferred generalization classes for gifted students. By designing and applying the generalization lesson using GSP, we tried to investigate the characteristics on the class. To do this, we designed a lesson on generalization of Viviani theorem and applied to 13 8th grade students in a math gifted class. As results, we could extract five subjects as followings; mediating the conjecture by GSP and checking the pattern, misunderstanding the confirm by GSP as a proof and its overcoming, digressing from the topic and cognitive gap, completing the proof by incomplete conjecture, gap between the generalization and understanding generality. Based on this subjects, we discussed the educational implications in order to help implement a preferred generalization classes for gifted students.

• Spatial Information Research
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• v.6 no.1
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• pp.11-23
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• 1998

Map generalization functions to visualize the spatial data or to change their scale by changing the level of details of data. Until recently, the studies on map generalization have concentrated more on line features than on point features. However, point features are one of the essential components of digital maps and cannnot be ignored because of the great amount of information they carry. This study, therefore, aimed to find out a detailed procedure of point features' generalization. Particularly, this work chose the distribution pattern of point features as the most important factor in the point generalization in investigating the geometric characteristics of source data. First, it attempted to find out the characteristics of distribution pattern of point features through quadrat analysis with Grieg-Smith method and nearest-neighbour analysis. It then generalized point features through the generalization threshold which did not alter the characteristics of distribution pattern and the removal of redudant point feautres. Therefore, the generalization procedure of point features provided by this work maintained the geometric characteristics as much as possible.

• Journal of Korean Society for Geospatial Information Science
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• v.8 no.2 s.16
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• pp.35-46
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• 2000

The digital maps, important data to build NGIS, require different scales in the same area. The organization for producing a digital map tries to find product method for digital map with economical efficiency and quality. The objectives of this study is to develope digital map generalization system to solve above problems. In order to develop this system, the work processing for digital map generalization is established, the analysis of related law and analysis on maps in different scales were performed, and each of digital map generalization algorithms was compared. The result of digital map generalization using this system shows that have a good result about positional accuracy which was evaluated by comparison between the generalized 1/25,000 and the corresponding 1/5,000 digital map. Furthermore, this system reduce the time required for 1/25,000 digital map production and the physical data amount by around 80%. In conclusion, the generalization system developed for this research can be useful for the digital map generalization from large scale to small scale digital map.

• Korean Journal of Mathematics
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• v.26 no.4
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• pp.665-674
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• 2018

A generalization of Ostrowski-type inequality involving functions of two independent variables is given.

• School Mathematics
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• v.10 no.1
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• pp.23-42
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• 2008

The purpose of this study was to describe characteristics of thinking in elementary gifted students' solutions to algebraic tasks. Especially, this paper was focused on the students' strategies to develop generalization while problem solving, the justifications on the generalization and metacognitive thinking emerged in stildents' problem solving process. To find these issues, a case study was conducted. The subjects of this study were four 6th graders in elementary school-they were all receiving education for the gifted in an academy for the gifted attached to a university. Major findings of this study are as follows: First, during the process of the task solving, the students varied in their use of generalization strategies and utilized more than one generalization strategy, and the students also moved from one strategy toward other strategies, trying to reach generalization. In addition, there are some differences of appling the same type of strategy between students. In a case of reaching a generalization, students were asked to justify their generalization. Students' justification types were different in level. However, there were some potential abilities that lead to higher level although students' justification level was in empirical step. Second, the students utilized their various knowledges to solve the challengeable and difficult tasks. Some knowledges helped students, on the contrary some knowledges made students struggled. Specially, metacognitive knowledges of task were noticeably. Metacognitive skills; 'monitoring', 'evaluating', 'control' were emerged at any time. These metacognitive skills played a key role in their task solving process, led to students justify their generalization, made students keep their task solving process by changing and adjusting their strategies.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.1
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• pp.37-44
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• 2003

This study is focused on development of generalization processing for 1/25,000 digital mapping using l/5,000 digital map. The generalization processing for digital map included in spatial and attribute information consists of 3 steps. The first, elimination of layer which is not included in 1/25,000 feature code. The second, classification of 8 feature codes. The third, merging of spatial and attribute information. Therefore using generalization workflow developed in this project, automatic generalization system will develope optimal in the future and also contribute product to small scale digital map and thematic map.

• School Mathematics
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• v.9 no.2
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• pp.313-326
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• 2007

Recently in algebra curriculum, to recognizes and explains general nile expressing patterns is presented as the one alternative and is emphasized. In the seventh School Mathematic Curriculum regarding 'regularity and function' area, in elementary school curriculum, is guiding pattern activity of various form. But difficulty and problem of students are pointing in study for learning through pattern activity. In this article, emphasizes generalization process through research activity of pictorial/geometric pattern that is introduced much on elementary school mathematic curriculum and investigates various approach and strategy of student's thinking, state of symbolization in generalization process of pictorial/geometric pattern. And discusses generalization of pictorial/geometric pattern, difficulty of symbolization and suggested several proposals for research activity of pictorial/geometric pattern.