• Journal of Korean Institute of Industrial Engineers
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• v.41 no.1
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• pp.64-73
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• 2015

Recent emergence of spatial big data attracts the attention of various research groups. This paper analyzes the research trend on spatial big data by text mining the related Scopus DB. We apply topic model and network analysis to the extracted abstracts of articles related to spatial big data. It was observed that optics, astronomy, and computer science are the major areas of spatial big data analysis. The major topics discovered from the articles are related to mobile/cloud/smart service of spatial big data in urban setting. Trends of discovered topics are provided over periods along with the results of topic network. We expect that uncovered areas of spatial big data research can be further explored.

• Atmosphere
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• v.20 no.3
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• pp.343-353
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• 2010

A regional wind network with complex surface conditions must be designed with sufficient space and time resolution to resolve the local circulations. In this study, the spatial variations of the wind field observed in the Seoul and Jeju regional networks were evaluated in terms of annual, seasons, and months to assess the spatial homogeneity of wind fields within the regional networks. The coherency of the wind field as a function of separation distance between stations indicated that significant coherency was sometimes not captured by the network, as inferred by low correlations between adjacent stations. A meso-velocity scale was defined in terms of the spatial variability of the wind within the network. This problem is predictably most significant with weak winds, dull prevailing wind, clear skies and significant topography. The relatively small correlations between stations imply that the wind at a given point cannot be estimated by interpolating winds from the nearest stations. For the Seoul and Jeju regional network, the meso-velocity scale has typically a same order of magnitude as the speed of the network averaged wind, revealing the large spatial variability of the Jeju network station imply topography and weather. Significant scatter in the relationship between spatial variability of the wind field and the wind speed is thought to be related to thermally-generated flows. The magnitude of the mesovelocity scale was significantly different along separation distance between stations, wind speed, intensity of prevailing wind, clear and cloudy conditions, topography. Resultant wind vectors indicate much different flow patterns along condition of contributing factors. As a result, the careful considerations on contributing factors such as prevailing wind in season, weather, and complex surface conditions with topography and land/sea contrast are required to assess the spatial variations of wind field on a regional network. The results in the spatial variation from the mesovelocity scale are useful to represent the characteristics of regional wind speed including lower surface conditions over the grid scale of large scale atmospheric model.

• Journal of the Korean Regional Science Association
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• v.11 no.2
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• pp.53-63
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• 1995

Changes in transport are reflected in the accessibility of a place, which is denoted as the inherent advantageous characteristics of a place with respect to overcoming spatial friction, and affect the land use ultimately. A composite accessibility measurement scheme is developed and applied to the subway network in Seoul, which has been constructed in 1972. Changes in the transport network are reflected in the spatial structure of accessibility and affect ultimately the land use pattern. Therefore, it is of relevance to examine the changes in the spatial structure of accessibility, which allows to forecast the direction of changes in the land use pattern.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.3
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• pp.80-91
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• 2008

The Purpose of this study is the applicaion of social network analysis for expanding the use of spatial data in local government. Spatial data generated from UIS projects play very important roles as a means of supporting decision making and solving complicated urban problems, but the utilization of the spatial data has not reach the expected level, considering to the huge amount of investment. Accordingly, there should be efforts in efficient management of spatial data, establishment of a sharing system, and expanded utilization of spatial data. Social network analysis applied to this research is a theory that explains the behaviors and patterns of units forming the system and measures distances between nodes, strength, etc. based on relations among nodes forming the network and the structural characteristics of the network. According to the results of surveying civil servants who were using spatial data on Busan Metropolitan City, obstacles to the sharing of spatial data were mostly non technical factors related to data users' attitude and their relations with circumstances. In order to expand the use of spatial data, this study performed social network analysis that applied the theory of planned behavior and examined the flow of spatial data, and by doing so, we analyzed related personnel's perception, identified obstacles to data sharing, and suggested a framework for promoting the expanded utilization of spatial data.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.8
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• pp.3641-3655
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• 2016

Wireless sensor networks (WSNs) provide a promising approach to monitor the physical environments, to prolong the network lifetime by exploiting the mutual correlation among sensor readings has become a research focus. In this paper, we design a hierarchical network framework which guarantees layered-compression. Meanwhile, a data sorting-based adaptive spatial compression scheme (DS-ASCS) is proposed to explore the spatial correlation among signals. The proposed scheme reduces the amount of data transmissions and alleviates the network congestion. It also obtains high compression performance by sorting original sensor readings and selectively discarding the small coefficients in transformed matrix. Moreover, the compression ratio of this scheme varies according to the correlation among signals and the value of adaptive threshold, so the proposed scheme is adaptive to various deploying environments. Finally, the simulation results show that the energy of sorted data is more concentrated than the unsorted data, and the proposed scheme achieves higher reconstruction precision and compression ratio as compared with other spatial compression schemes.

• ETRI Journal
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• v.25 no.2
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• pp.140-143
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• 2003

In this paper, we present a probabilistic approach to determining whether extracted facial features from a video sequence are appropriate for creating a 3D face model. In our approach, the distance between two feature points selected from the MPEG-4 facial object is defined as a random variable for each node of a probability network. To avoid generating an unnatural or non-realistic 3D face model, automatically extracted 2D facial features from a video sequence are fed into the proposed probabilistic network before a corresponding 3D face model is built. Simulation results show that the proposed probabilistic network can be used as a quality control agent to verify the correctness of extracted facial features.

• 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.

• The KIPS Transactions:PartD
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• v.13D no.3 s.106
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• pp.325-336
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• 2006

For supporting LBS service, recent studies on spatial network databases (SNDB) have been done actively. In order to gain good performance on query processing in SNDB, we, in this paper. design efficient storage and index structures for spatial network data, point of interests (POIs), and moving objects on spatial networks. First, we design a spatial network file organization for maintaining the spatial network data itself consisting of both node and edges. Secondly, we design a POI storage and index structure which is used for gaining fast accesses to POIs, like restaurant, hotel, and gas station. Thirdly, we design a signature-based storage and index structure for efficiently maintaining past, current, and expected future trajectory information of moving objects. Finally, we show that the storage and index structures designed in this paper outperform the existing storage structures for spatial networks as well as the conventional trajectory index structures for moving objects.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.331-342
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• 1998

본 연구에서는 공간정보를 활용한 전산망 관리시스템을 개발하고자 한다. 이 시스템은 Spatial Data Manager, Network Manager, 3D Viewer 세 부분으로 구성되었다. Spatial Data Manger는 공간상의 Network 장비 및 각종 시설물의 위치와 속성정보를 보여준다. 속성정보 중에서 IP(Internet Protocol)정보는 Network Manager와 연결된다. Network Manager는 ICMP(Internet Control Message Protocol)를 사용하여 네트워크 상태를 파악한다. 3D Viewer는 사용자가 원하는 위치 및 방향에서 시설물을 볼 수 있도록 한다. Spatial Data Manager의 좌표는 3D Viewer의 Camera 좌표와 연동하여 사용자가 원하는 지역을 동시에 2차원과 3차원형태로 볼 수가 있다. 기존 전산망 관리시스템이 단지 수치적으로 네트워크의 상태에 관한 정보를 보여주던 것에 비하여, 개발된 시스템은 공간 위치를 같이 보여줌으로써 누전, 누수 등과 같이 다른 시설물이 전산망에 미칠 수 있는 영향과 전산망 케이블의 종류에 따라 다른 길이의 제약에 따른 영향 등을 분석할 수가 있다. 또한 다른 시설물의 도면 및 시설물에 관련된 기타 정보를 빠르게 검색할 수 있으므로 전산망관리 뿐만 아니라 통합적인 관리를 할 수 있다. 이를 통해 전산망 관리비용을 줄일 수 있을 것으로 기대된다.

• Journal of Korea Spatial Information System Society
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• v.3 no.2 s.6
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• pp.53-61
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• 2001

The GIS Network consists of the Clearinghouse Network Gateway and Clearinghouse Node and Geo-spatial Data Server. Recently with the development of Information and Network technologies, GIS Network should be needed to be more secure than ever. In this paper, we proposed the effective access control method for the distributed GIS network. PKI (Public Key Infrastructure) Technologies are used for access control and security for transmission on Geo-spatial data