• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.151-153
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• 2001

Feature Simplification is an essential method for multiple representations of spatial features in GIS. However, spatial features re various, complex and a alrge size. Among spatial features which describe spatial information. linear feature is the msot common. Therefore, an efficient linear feature simplification method is most critical for spatial feature simplification in GIS. This paper propose an original method, by which the problem of linear feature simplification is mapped into the signal processing field. This method avoids conventional geometric computing in existing methods and exploits the advantageous properties of wavelet transform. Experimental results are presented to show that the proposed method outperforms the existing methods and achieves the time complexity of O(n), where n is the number of points of a linear feature. Furthermore, this method is not bound to two-dimension but can be extended to high-dimension space.

• Environmental Analysis Health and Toxicology
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• v.28
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• pp.9.1-9.5
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• 2013

Objectives Geographic Information Systems (GIS) is a powerful tool for assessing exposure in epidemiologic studies. We used GIS to determine the geographic extent of contamination by perfluorooctanoic acid, C8 (PFOA) that was released into the environment from the DuPont Washington Works Facility located in Parkersburg, West Virginia. Methods Paper maps of pipe distribution networks were provided by six local public water districts participating in the community cross-sectional survey, the C8 Health Project. Residential histories were also collected in the survey and geocoded. We integrated the pipe networks and geocoded addresses to determine which addresses were serviced by one of the participating water districts. The GIS-based water district assignment was then compared to the participants' self-reported source of public drinking water. Results There were a total of 151,871 addresses provided by the 48,800 participants of the C8 Health Project that consented to geocoding. We were able to successfully geocode 139,067 (91.6%) addresses, and of these, 118,209 (85.0%) self-reported water sources were confirmed using the GIS-based method of water district assignment. Furthermore, the GIS-based method corrected 20,858 (15.0%) self-reported public drinking water sources. Over half (54%) the participants in the lowest GIS-based exposure group self-reported being in a higher exposed water district. Conclusions Not only were we able to correct erroneous self-reported water sources, we were also able to assign water districts to participants with unknown sources. Without the GIS-based method, the reliance on only self-reported data would have resulted in exposure misclassification.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.10a
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• pp.55-61
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• 2004

In this study, we tried to develop the Web-GIS system prototype that will be able to effectively manage the nationwide flood prevention operations and to establish a framework that will be able to maintain the operation consistency. To achieve the study goals, we analysed current system of flood prevention operations, gathered related documents, had interviews with many government employees, and developed the Web-GIS system prototype. Also, we tried to present the benefit-cost analysis method using GIS technique that will be used to decide the priority order of the operation.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2223-2225
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• 2005

In this work, experimental investigation has been mainly done. For this purpose, UHF sensor has been designed and fabricated to detect the partial discharges produced from the 10 artificial defects introduced into the real scale 70kV GIS mock-up under the high voltage at the well shielded room. And also, in order to verify the applicability of the proposed method at the site, the proposed CAPD (chaos analysis of partial discharge) is combined with spectral analysis method in order to identify the nature of the above 10 defects. The PD pattern recognition of each defect has been fulfilled by applying self developed artificial neural network soft ware. The result shows that the recognition rate is reached to be 80% by newly proposed method while the traditional PRPD analysis method leads us to obtain 41%. In consequence, it can be pointed out that the proposed method seems likely to be applicable to the real GIS at the site.

• Journal of the Korean Geographical Society
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• v.46 no.3
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• pp.366-381
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• 2011

A competitive location problem in discrete space is computationally difficult to solve in general because of its combinatorial feature. In this paper, we address an alternative method for solving competitive location problems in discrete space, particularly employing deterministic allocation. The key point of the suggested method is to reducing the number of predefined potential facility sites associated with the size of problem by utilizing geometric concepts. The suggested method was applied to the existing broadband marketplace with increasing competition as an application. Specifically, we compared computational results and spatial configurations of two different sized problems: the problem with the original potential sites over the study area and the problem with the reduced potential sites extracted by a GIS-based geometric algorithm. The results show that the competitive location model with the reduced potential sites can be solved more efficiently, while both problems presented the same optimal locations maximizing customer capture.

• Journal of Korea Multimedia Society
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• v.16 no.11
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• pp.1239-1249
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• 2013

According to development of weather radar, researches about observation, analysis or forecast of weather phenomena such as tornado, flash-flood etc. were encouraged by reducing frequency interferences, transmission noises, attenuations of radar signal. In contrast, there is a growing interest in the visualization and expression methods for weather radar data but weather radar manufacturers or the organs of government for weather are just busy interpreting expressed weather images projected on GIS. We propose an effective high definition weather radar information visualization method able to apply various GIS platforms to observe and take actions against rapid local weather changes effectively. In this paper, first we change information acquired from weather radar to raster or vector type high definition data structures using specific algorithms. And then, we quadrate our processed raster/vector type weather data with various GIS platforms accurately to make observers can recognize and check weather situations over exact geographical positions and elevations intuitively. Experimental results verify that our method make observers can recognize and analyze weather changes, tornados, local downpours or flash floods accurately by analyzing high definition weather radar data combined with GIS platform including detailed target locations and elevations.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.5
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• pp.510-519
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• 2002

The OpenGIS Consortium has proposed a new web-mapping technology to support interoperability in web GIS environment by developing the specifications of MapServer and GML. In this environment, the MapServer transforms legacy spatial data into GML data, and clients display them on standard web browsers. This web-mapping testbed proposes methods for discovering, accessing, integrating and displaying GIS information except processing of spatial operations which are essential services in GIS environment. This paper proposes the method for executing spatial operations on GML data which are overlays of different map layers in legacy data servers. To support spatial operations on GML data in web GIS environment, this paper designs and implements GDOM based on the W3C's DOM Specifications and OGC's Simple Features Specifications. This paper shows the specifications and implementation of GDOM and the process of spatial operations in web-mapping testbed environment.

• Spatial Information Research
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• v.12 no.1
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• pp.1-12
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• 2004

The 3-dimensional GIS data provider system manages and retrieves 2, 3-dimensional spatial and time data. This system provides the standard interfaces which help developers to omit additional works to do modify or convert a format of 2 or 3-dimensional spatial data, which has been already accumulated, into that dependent on a specified system. This system consists of a data provider and data access component. The former deals with the connections with some databases and manages the meta data, so that the various GIS or software can access to 3-dimensional spatial and time data via the same method, and the latter takes charge of index management and spatial operations on GIS data for consumers. The system offers the diverse spatial operations and analysis functions for 3-dimensional GIS.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.3
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• pp.70-80
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• 2001

It is necessary to construct an effective regional information system in facing the incoming information intensive society. Many local government in Korea began to recognize a need for constructing a GIS(Geographic Information System) and they are planning to construct GIS´s to improve their administrative efficiency. However, ti requires high-priced hardware, software, and an experienced operator to sue a GIS effectively. The purpose of this study is to develop the GIS program which can be sued with ease by common users. By developing a GIS functioned program using a coordinate recognition module by application of geo-spatial data, and a digital map which is already made, this program can be used efficiently only by only inputting attributes without high-priced hardware and software, and can be utilized easily to every purposes of work with geo-spatial data and attributes. MapObjects, mapping and GIS component, was employed to use geo-spatial data, and Access 97 from Microsoft to manage and attributes database. Visual Basic, objected-oriented language, was used to develop an application program. Results of this study were applied to constructing the Information system of Kanwon National University. This program could be used for various purposed by common users without additional hardware and software.

• 한국전산유체공학회:학술대회논문집
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• 2006.05a
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• pp.21-26
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• 2006

A large-scale finite element simulation and modeling method is presented for environmental flows in urban area. Parallel stabilized finite element method based on domain decomposition method is employed for the numerical simulation. Several GIS and CAD data are used for the preparation of the shape model for landform and urban structures. The present method Is applied to the simulation of flood flow and wind flow In urban area. The present method is shown to be a useful planning and design tool for the natural disasters and the change of environments in urban area.