Yoon-Chul Choy

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There are many studies on retrieval methods for structured documents but most of the studies are for those whose structure information is expressed by elements. But when elements are used to describe a document structure, the structure becomes static and difficult to expand. So describing a document structure using attributes is used in many standards. But(More)
ÐGeometric structure analysis is a prerequisite to create electronic documents from logical components extracted from document images. This paper presents a knowledge-based method for sophisticated geometric structure analysis of technical journal pages. The proposed knowledge base encodes geometric characteristics that are not only common in technical(More)
—This paper presents a syntactic method for sophisticated logical structure analysis that transforms document images with multiple pages and hierarchical structure into an electronic document based on SGML/XML. To produce a logical structure more accurately and quickly than previous works of which the basic units are text lines, the proposed parsing method(More)
—SGML/XML are having a profound impact on data modeling and processing. This paper presents an efficient algorithm to compute differences between old and new versions of an SGML/XML document. The difference between the two versions can be considered to be an edit script that transforms one document tree into another. The proposed algorithm is based on a(More)
Developing an automated vectorizing system as an input method for a geographic information system (GIS) is of extreme importance due to the fact that an input process takes a lot of time and cost in constructing a GIS. Most vectorizing systems require users to set the parameters as appropriately as possible for a particular map image, but it is quite(More)
Recently, there is a growing interest from various fields of studies in GIS which promotes efficient storage and retrieval of geographic information. The development of automated vectorizing system, an input method for GIS, is of extreme importance due to the fact that this part of constructing a GIS has been time consuming. Most vectorizing systems require(More)
Navigating in a three dimensional (3D) virtual environment is difficult mainly because of limited navigational information that can only offer a screen-size visualization and low level imitation of other human senses. To address this problem, studies on various methods of navigation aid have been carried out. The navigation aid described in this paper was(More)