• Journal of Korea Multimedia Society
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• v.22 no.12
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• pp.1466-1480
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• 2019

This paper addresses the efficient processing of all-farthest-neighbors (AFN) queries in spatial network databases. Given a set of data points P={p₁,p₂,…,p_|p|} in a spatial network, where the distance between two data points p and s, denoted by dist (p,s), is the length of the shortest path between them, an AFN query is defined as follows: find the farthest neighbor ω(p)∈P of each data point p such that dist(p,ω(p)) ≥ dist(p,s) for all s∈P. In this paper, we propose a shared execution algorithm called FAST (for All-Farthest-neighbors Search in spatial neTworks). Extensive experiments on real-world roadmaps confirm the efficiency and scalability of the FAST algorithm, while demonstrating a speedup of up to two orders of magnitude over a conventional solution.

• Spatial Information Research
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• v.21 no.1
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• pp.1-13
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• 2013

This paper describes a GIS framework for geo-semantic information retrieval in mobile computing environments. We built geographic ontologies of POI (point of interest) and weather information for use in the combination of semantic, spatial, and temporal functions in a fully integrated database. We also implemented a geo-semantic app for Android-based smartphones that can extract more appropriate POIs in terms of user contexts and geographic ontologies and can visualize the POIs using Google Maps API (application programming interface). The feasibility tests showed our geo-semantic app can provide pertinent POI information according to mobile user contexts such as location, time, schedule, and weather. We can discover a baking CVS (convenience store) in the test of bakery search and can find out a drive-in theater for a not rainy day, which are good examples of the geo-semantic query using semantic, spatial, and temporal functions. As future work, we should need ontology-based inference systems and the LOD (linked open data) of various ontologies for more advanced sharing of geographic knowledge.

• Journal of the Korean Geographical Society
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• v.39 no.3
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• pp.444-456
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• 2004

Recently spatial modeling that combined GIS and Cellular Automata(CA) which are based on dynamic process modeling has been discussed and investigated. However, CA-based spatial modeling in previous research only provides the general modeling framework and environment, but lacks of providing simulation or transition rules for modeling. This study aims to propose a methodology for extracting spatial relation rules using GIS and Knowledge Discovery in Database(KDD) methods. This new methodology has great potentials to improve CA-based spatial modeling and is expected to be applied into several examples including urban growth simulation modeling.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.266-268
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• 2003

This is based on the AGENT-LUC model framework. Luangprabang Province has the largest percentage of shifting cultivation area in Laos PDR. The model simulates the spatial and temporal patterns of the shifting cultivation in the study area, using a GIS database while the total area of shifting cultivation is controlled by supply and demand balance of food. The model simulation period is from 1990 to 1999, at a spatial resolution of 500m. The results are evaluated using statistical data and remote sensing images. Through the validation, it is concluded that the trends simulated agrees to that of statistical data and the spatial and temporal patterns are also replicated satisfactorily.

• Journal of Korean Society for Geospatial Information Science
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• v.4 no.1 s.6
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• pp.43-55
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• 1996

The objective of this research is to design a digital map database structure supporting video images which is one of the fundamental elements of hypermap. In order to reach the research objective, the work includes the identification of the relationships between two dimensional digital map database and video elements. The proposed database model has functions for interactive browsing between video image frames and specific points on two dimensional digital map, fer connecting the map elements and features on video images. After that, the images and the database are transformed to the pilot system fer testing the map database structure. The pilot project results indicate that the map database structure can integrate functionally two dimensional digital map and video images.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.6
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• pp.1-9
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• 2016

Place names of road sign mean various place names being used on road signs for path guidance of drivers such as administrative district, facility, road, etc. It is very important that not only the choice method of place names for connectivity of road signs but standard establishment of spatial impact zone according to place names. However this standard are not established currently, so it is difficult to fix the spatial range for changing place names around the main facility according to the new construction or relocation of main facility in urban region. Considering the use of big data, one of the Government 3.0, we need to utilize actively the road sign management system database. This paper suggested a methodology for standard establishment of spatial impact zone according to place names of road sign in urban regions based on the road sign management system database. To perform a case study, we selected a major facility ("City Hall") which is the most frequently used the place name of road signs and presented standard of spatial impact zone by urban size in 84 cities.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.684-695
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• 2010

Geographic information system (GIS) is being increasingly used for decision making, planning and agricultural environment management because of its analytical capacity. GIS and remote sensing have been combined with environmental models for many agricultural applications on monitoring of soils, agricultural water quality, microbial activity, vegetation and aquatic insect distribution. This paper introduce principles, vegetation indices, spatial data structure, spatial analysis of GIS and remote sensing in agricultural applications including terrain analysis, soil erosion, and runoff potential. National Academy of Agricultural Science (NAAS), Rural Development Administration (RDA) has a spatial database of agricultural soils, surface and underground water, weeds, aquatic insect, and climate data, and established a web-GIS system providing spatial and temporal variability of agricultural environment information since 2007. GIS-based interactive mapping system would encourage researchers and students to widely utilize spatial information on their studies with regard to agricultural and environmental problem solving combined with other national GIS database. GIS and remote sensing will play an important role to support and make decisions from a national level of conservation and protection to a farm level of management practice in the near future.

• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.511-519
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• 2016

National Institute of Environmental Research (NIER) has developed the Korean Reach File (KRF) for scientific and systematic analysis of variables related to water quality, pollutant sources and aquatic ecosystems in consideration of steam reach networks. The KRF provides a new framework for data production, storage, management and analysis for water related variables in relation to spatial characteristics, connections, and topologies of stream reaches. However, the current version of KRF (ver.2) has limited applicability because its nodes include not only the stream points based on topological characteristics but also those based on water quality monitoring stations, which may undermine its generality. In this study, a new version of KRF (ver.3) was designed and established to overcome the weak point of version 2. The version 3 is a generalization of the old KRF graphic data and it integrates the attribute data while separating it from the graphic data to minimize additional work that is needed for data association and search. We tested the KRF (ver.3) on actual cases and convenience and adaptability for each application was verified. Further research should focus on developing a database link model and real-world applications that are targeted to process event data.

• Korean Journal of Remote Sensing
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• v.27 no.3
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• pp.379-388
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• 2011

At present, GEOBIA (Geographic Object-based Image Analysis), heir of OBIA (Object-based Image Analysis), is regarded as an important methodology by object-oriented paradigm for remote sensing, dealing with geo-objects related to image segmentation and classification in the different view point of pixel-based processing. This also helps to directly link to GIS applications. Thus, GEOBIA software is on the booming. The main theme of this study is to look into the applicability of geo-spatial processing open source to GEOBIA. However, there is no few fully featured open source for GEOBIA which needs complicated schemes and algorithms, till It was carried out to implement a preliminary system for GEOBIA running an integrated and user-oriented environment. This work was performed by using various open sources such as OTB or PostgreSQL/PostGIS. Some points are different from the widely-used proprietary GEOBIA software. In this system, geo-objects are not file-based ones, but tightly linked with GIS layers in spatial database management system. The mean shift algorithm with parameters associated with spatial similarities or homogeneities is used for image segmentation. For classification process in this work, tree-based model of hierarchical network composing parent and child nodes is implemented by attribute join in the semi-automatic mode, unlike traditional image-based classification. Of course, this integrated GEOBIA system is on the progressing stage, and further works are necessary. It is expected that this approach helps to develop and to extend new applications such as urban mapping or change detection linked to GIS data sets using GEOBIA.

• Journal of Veterinary Clinics
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• v.36 no.1
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• pp.15-22
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• 2019

Highly pathogenic avian influenza (HPAI) is among the top infectious disease priorities in Korea and the leading cause of economic loss in relevant poultry industry. An understanding of the spatial epidemiology of HPAI outbreak is essential in assessing and managing the risk of the infection. Though previous studies have reported the majority of outbreaks occurred clustered in what are preferred to as densely populated poultry regions, especially in southwest coast of Korea, little is known about the spatial distribution of risk areas vulnerable to HPAI occurrence based on geographic information system (GIS). The main aim of the present study was to develop a GIS-based risk index model for defining potential high-risk areas of HPAI outbreaks and to explore spatial distribution in relative risk index for each 252 Si-Gun-Gu (administrative unit) in Korea. The risk index was derived incorporating seven GIS database associated with risk factors of HPAI in a standardized five-score scale. Scale 1 and 5 for each database represent the lowest and the highest risk of HPAI respectively. Our model showed that Jeollabuk-do, Chungcheongnam-do, Jeollanam-do and Chungcheongbuk-do regions will have the highest relative risk from HPAI. Areas with risk index value over 4.0 were Naju, Jeongeup, Anseong, Cheonan, Kochang, Iksan, Kyeongju and Kimje, indicating that Korea is at risk of HPAI introduction. Management and control of HPAI becomes difficult once the virus are established in domestic poultry populations; therefore, early detection and development of nationwide monitoring system through targeted surveillance of high-risk spots are priorities for preventing the future outbreaks.