• Journal of Korean Elementary Science Education
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• v.40 no.3
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• pp.390-406
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• 2021

This study investigated how elementary students with different spatial ability constructed spatial thinking process about on volcanoes and earthquakes with GeoMapApp-based materials. Students' spatial thinking process was analyzed in terms of spatial concept recognized, tools of spatial representation, and their spatial reasoning to construct topographic structure. The student group with high-scored spatial ability showed the spatial reasoning based on internal representation of building mental images through sectional division of horizontal distance, directly connected with spatial concept, or distorting spatial concept. The student group with low-scored spatial ability built the spatial reasoning directly connected with spatial concept instead of transforming into internal representation, and partially recognized spatial concept on either distance or depth. Based on the results, we argued identifying spatial concepts such as distance, height, or depth from the GeoMapApp data would be funda- mental for the better spatial thinking.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.5
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• pp.47-56
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• 2003

Geometric cutting-simulation and verification play an important role in detecting NC machining errors in mold & die manufacturing and thereby reducing correcting time & cost on the shop floor. Current researches in the area may be categorized into view-based, solid-based, and discrete vector-based methods mainly depending on workpiece models. Each methodology has its own strengths and weaknesses in terms of computing speed, representation accuracy, and its ability of numerical inspection. The paper proposes a hybrid modeling scheme for workpiece representation with z-map model and discrete vector model, which performs 3-axis and 5-axis cutting-simulation via tool swept surface construction by connecting a sequence of silhouette curves.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.212-217
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• 1992

In this paper, a two ports machine(TPM) model for discrete event dynamic systems(DEDS) is proposed. The proposed model is a finite state machine which has two inputs and two outputs. Inputs and outputs have two components, events and informations. TPM is different from other state machine models, since TPM has symmetric input and output. This symmetry enables the block diagram representation of the DEDS with TPM blocks, summing points, multiplying points, branch points, and connections. The graphical representation of DEDS is analogous to that of control system theory. TPM has a matrix representation of its transition and information map. This matrix representation simplifies the analysis of the DEDS.

• Spatial Information Research
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• v.19 no.1
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• pp.73-82
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• 2011

Recently, demand for the use of cadastral map is increasing in both public and private area. To use cadastral map in web or mobile environment, construction of the multi-representation database(MRDB) that is the compressed into multiple scale from the original map data is recommended. In this study, the map generalization methodology for the cadastral map by applying overlay with topographic map and polygon generalization technique is suggested. This process is composed of three steps, re-constructing the network data of topographic map, polygon merging of parcel lines according to network degree, and applying line simplification techniques. Proposed methodologies are applied to the cadastral map in Suwon area. The result map was generalized into 1:5,000, 1:20,000, 1:100,000 scale, and data compression ratio was shown in 15% 8% 1% level respectively.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.2
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• pp.73-79
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• 2010

The most popular technique for image retrieval in a heterogeneous collection of color images is the comparison of images based on their color histogram. The color histogram describes the distribution of colors in the color space of a color image. In the most image retrieval systems, the color histogram is used to compute similarities between the query image and all the images in a database. But, small changes in the resolution, scaling, and illumination may cause important modifications of the color histogram, and so two color images may be considered to be very different from each other even though they have completely related semantics. A new method of color feature representation based on the 3-dimensional RGB color map is proposed to improve the defects of the color histogram. The proposed method is based on the three 2-dimensional projection map evaluated by projecting the RGB color space on the RG, GB, and BR surfaces. The experimental results reveal that the proposed is less sensitive to small changes in the scene and that achieve higher retrieval performances than the traditional color histogram.

• Journal of information and communication convergence engineering
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• v.2 no.2
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• pp.123-127
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• 2004

The most popular technique for image retrieval in a heterogeneous collection of color images is the comparison of images based on their color histogram. The color histogram describes the distribution of colors in the color space of a color image. In the most image retrieval systems, the color histogram is used to compute similarities between the query image and all the images in a database. But, small changes in the resolution, scaling, and illumination may cause important modifications of the color histogram, and so two color images may be considered to be very different from each other even though they have completely related semantics. A new method of color feature representation based on the 3-dimensional RGB color map is proposed to improve the defects of the color histogram. The proposed method is based on the three 2-dimensional projection map evaluated by projecting the RGB color space on the RG, GB, and BR surfaces. The experimental results reveal that the proposed is less sensitive to small changes in the scene and that achieve higher retrieval performances than the traditional color histogram.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.10 no.2
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• pp.63-71
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• 1992

The digital map database is often produced for multiple purposes, including mapping at multiple scales; it is increasingly rare that a base map is digitized for mapping at a single scale. The most important problems in process of line simplification in map generalization and multiple representation is that tolerance value selected for simplifying base map information must be modified as feature geometry varies within the digital file to ensure both accuracy and recognizability of graphic details on a generalized map. In this study, we explored various algorithms regarding to line simplication at many scales from a single digital file, and presents a rule by which to determine those scale at which line feature geometry might be expected to change in map representation. By applying two measured of displacement between a digitized line and its simplification, five algorithms have been evaluated. The results indicate that, of the five, the Douglas-Peucker routine produced less displacement between a line and its simplification. The research has proved to automating map simplification, incorporating numeric guidelines into digital environment about what magnitude and variation in geometric detail should be preserved as the digital data is simplified for representation at reduced map scales.

• Journal of the Korean Institute of Gas
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• v.9 no.2 s.27
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• pp.28-33
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• 2005

Because chemical industrial facilities deal with large amount of hazardous materials, the damage affect to off-site as well as on-site when an accident occurs. So it is necessary to develop a Risk Representation System for effective control and response to major accidents. In this study a Risk Representation System(S/W) was developed to help analyzing actual risk and to set an alternative that can reduce the analyzed risk by drawing the level of individual plant's risk on a digital map network.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.488-490
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• 2003

Over the past few years, a number of studies have been made on web map services, which enable the GIS user to access spatial data through the web. They, however, have focused on only implementation techniques separately, such as map client implementation, map server implementation, communication between client and server, and the map data representation. Therefore, it is hard to share and practical use the spatial data, because they does not ensure interoperability in heterogeneous map servers. In this paper, we have designed and implemented the web map server with open architecture, which complies with the standard interfaces proposed by OpenGIS Consortium (OGC). In particular, we have extended the OGC’s interfaces for a map server to support one or more data sources. This paper has contributed to construction and practical use of web map services by newly proposing the method of implementation of a map server, which could be reused regardless of the types of data sources.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.6
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• pp.135-140
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• 2015

The Cyber-Physical Systems (CPS) complexly perform modeling and simulation (M&S) for the various embedded systems. In this case, due to use diverse formatted models, we suggest to apply with the SEDRIS to systematically manage the different formatted data on M&S. The SEDRIS can reduce time and cost with reusing and interoperating environment data developed in the specific domain. To do this, we should input the data transformed the height map for terrain representation in a simulator into raster data of SEDRIS for which interoperate between the existed simulator and the SEDRIS. To solve the problem, we propose the transformation method to transfer the polygon data from RAW file used in terrain representation. With the proposed method, we can provide two advantages. First, it can possibly express the environment data into SEDRIS. Second, we can see the terrain like an image file through a viewer. Therefore, even non-expert easily constructs the terrain environment data.