• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.5015-5022
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• 2010

Most of the existing pattern mining techniques are capable of searching patterns according to the continuous change of the spatial information of an object but there is no constraint on the spatial information that must be included in the extracted pattern. Thus, the existing techniques are not applicable to the optimal path search between specific nodes or path prediction considering the nodes that a moving object is required to round during a unit time. In this paper, the precision of the path search according to the spatial hierarchy is analyzed using the Spatial-Temporal Optimal Moving Pattern(with Frequency & Weight) (STOPM(FW)) algorithm which searches for the optimal moving path by considering the most frequent pattern and other weighted factors such as time and cost. The result of analysis shows that the database retrieval time is minimized through the reduction of retrieval range applying with the spatial constraints. Also, the optimal moving pattern is efficiently obtained by considering whether the moving pattern is included in each hierarchical spatial scope of the spatial hierarchy or not.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.2158-2164
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• 2015

In u-GIS environments, various load shedding techniques have been researched in order to balance loads caused by input spatial data streams. However, typical load shedding methods on aspatial data lack regard for characteristics of spatial data, also previous load shedding approaches on spatial, which still lack regard for spatial data density or dynamic input data stream, give rise to troubles on spatial query processing performance and accuracy. Therefore, dynamic load shedding scheme over spatial data stream is proposed through stored spatial data deviation and load ratio of input data stream in order to improve spatial continuous query accuracy and performance in u-GIS environment. In proposed scheme, input data which are a big probability related to spatial continuous query may be a strong chance to be dropped relatively.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.917-923
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• 2004

With a rapid growing of information networks and development achievements in mobile technology the spatial information is one of the most important resources for modern daily life. But the speed of spatial information technology trends are far from the real service demands as compared to the other relevant fields, and it would be natural that this unbalanced gap between the supply and demand of spatial information technology is being resulted from the absence of appropriate modeling concepts at some extents. In this paper there would be shown a new approaching model for the spatial information system based on agent concepts, which is able to perform some spatial tasks if properly implemented afterward. And to give resonable background of the new modeling framework here also some known critics for the commonly used modeling approaches when they applied to spatial information modeling followed by several alternative requirements for a good spatial modeling framework. And also there would be some considerations for applying this approach to the marine geographic information communities.

• Spatial Information Research
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• v.19 no.5
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• pp.13-25
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• 2011

Until now, most of the Web GIS system has been developed with one-sided service type that provides pre-built spatial information to users. Recently, however, interactive web system is getting attention because users can create directly spatial information contents that meet their needs. In line with this trend, this study had a aim to develop a UGC(User Generated Contents) support system for marine science researchers who can generate spatial data by themselves on the web. The main advantage of this system is that it provides marine survey data and marine spatial information that needed to work for marine science research. Furthermore, it provides the functions of extracting of coastline as point data for their marine study area, and making of the spatial planning map for marine field survey work and marine science thematic maps for exploratory analysis after research survey. Such kinds of interactive UGC support system gives researchers a chance for utilizing marine spatial information more easily. Therefore, it is expected that the improving of the efficiency of research works, as well as increasing of the utilization of marine spatial data.

• Journal of Broadcast Engineering
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• v.20 no.6
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• pp.837-847
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• 2015

In this paper, the reception performance of spatial modulation multiple-output multiple-input (MIMO) is analyzed for high speed terrestrial broadcasting. The MIMO scheme is required to reduce the inter symbol interference (ISI) and spatial correlation. The spatial modulation scheme solves the problem of ISI, but the spatial correlation degrades the reception performance of SM scheme. The space-time block coded spatial modulation (STBC-SM) is combined the SM system with space-time block code (STBC) for reducing the effects of the spatial correlation. However, the STBC-SM scheme degrades the spectral efficiency by transmitting same data in the two symbol period. The double space-time transmit diversity with spatial modulation (DSTTD-SM) scheme transmits the data with full antenna combination. To adapt these SM MIMO systems into the terrestrial broadcasting system, the reception performance is analyzed using computer simulation in SUI channel environments.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.143-151
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• 2011

Since it is important to understand data acquiring characteristics through relationship between spatial types and spatial elements and apply it to spatial plans for smooth communication between designer and user of space, the conclusions gained from analysis of data acquiring characteristics of spatial elements through image evaluation by types of interior space can be summarized as in the followings: First, for the amount of acquired data by types of interior space, it shows that the acquired amount of data is to change by types and data acquiring method (phrase and image) even though the spatial elements are same. Second, for the data acquiring process of spatial types by gender, it shows that there is a big difference in acquiring of data according to the evaluation method by phrase and image. Third, for the amount of acquired data of spatial types by gender, it shows that there is a difference between male and female, which is by "classic ${\rightarrow}$ modern ${\rightarrow}$ natural" in case of male and "classic ${\rightarrow}$ natural ${\rightarrow}$ modern" in case of female. regarding both of phrase and image. Fourth, for the evaluation by gender, it shows that there is a deviation in the value of difference according to the elements by which data acquiring characteristics evaluate space. It is considered that this deviation characteristic is in need of reflection in the process of spatial evaluation. This study analyzed data acquiring characteristics of space user's spatial elements through image evaluation by types of space to understand how data acquiring would be changed of spatial elements according to type and gender. Through this study, it expects to make clear that, when a designer is planning a certain space, if the space can be a space for the user by understanding of which elements should be exposed to users by types to acquire more data.

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.2 s.40
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• pp.43-49
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• 2007

In this study, a GIS spatial analysis method adopted fuzzy concept was introduced and land suitability analysis of waste landfill were conducted through this method. Previous studies conducted site evaluation and land suitability analysis by appling spatial overlay of conventional GIS that based on the boolean logic of crisp set. However these method can not consider the uncertainty of spatial data and the incongruity of data classification criteria, because these method handle spatial data based on the boolean logic of crisp set. As not provided trustable analysis result, conventional GIS spatial overlay method lacks opportunity for expanding use in reality. This study selected waste landfill as facility for analysis and applied fuzzy spatial analysis method as an objective approach. In the concrete contents of study, a series process with regard to the definition procedure of membership function for continuous data and the fuzzy input value generation of spatial data for fuzzy analysis is established. As a result, in this study we proposed a method that derive parameters for deciding the membership function of spatial data by considering the criterion of data classification and factor selection for land suitability analysis of waste landfill.

• Journal of KIISE:Databases
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• v.32 no.5
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• pp.536-546
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• 2005

In this paper, we focus on the filtering step of candidate objects for spatial join operations on the input tables that none of the inputs is indexed. Over the last decade, several spatial Join algorithms for the input tables with index have been extensively studied. Those algorithms show excellent performance over most spatial data, while little research on solving the performance degradation in the presence of skewed data has been attempted. Therefore, we propose a spatial hash strip join(SHSJ) algorithm that can refine the problem of skewed data in the conventional spatial hash Join(SHJ) algorithm. The basic idea is similar to the conventional SHJ algorithm, but the differences are that bucket capacities are not limited while allocating data into buckets and SSSJ algorithm is applied to bucket join operations. Finally, as a result of experiment using Tiger/line data set, the performance of the spatial hash strip join operation was improved over existing SHJ algorithm and SSSJ algorithm.

• Journal of the Korean Society of Earth Science Education
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• v.6 no.1
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• pp.28-39
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• 2013

The purpose of this study is to investigate the conceptions about altitude of the Sun of elementary students according to differences by the spatial ability. In this study through the qualitative analysis, 4 students who were similar understanding levels of concepts to altitude of the Sun and differences by the spatial ability were selected out of 75 in 6th grade elementary located in Sunchang, Jellabuk-do Province. 4 students for the qualitative analysis were selected by the test instrument of spatial ability and altitude of the Sun. The results of study was students with higher spatial ability were higher understanding levels of concepts to altitude of the Sun. However, both of student with higher and lower spatial ability showed a false concept to the expanded concepts into outer space like a cause of seasonal change, change of altitude of the Sun by latitude unlike the intution. Students with lower spatial ability didn't form the scientific concepts, not only a cause of seasonal change and change of altitude of the Sun but also difference of energy density by altitude of the Sun. A student of two with lower spatial ability has been impediment strongly to form the scientific concept by the false concepts to the distance. The findings were as follows; Learning to altitude of the Sun regardless of the difference of spatial ability should be learned to interact to the intution, celestial movement and model experiment. To students with lower spatial ability should be developed teaching methods to understand the relation between the Sun and celestial movement.

• Spatial Information Research
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• v.12 no.4 s.31
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• pp.307-319
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• 2004

Managing GML data in traditional database systems is not efficient since It has not only characteristics of spatial data but also features of (semi) structured n documents. XML enabled database systems can manage U data efficiently, however they cannot handle spatial data. Spatial database systems are good at spatial data handling but those are inefficient for XML data. This paper proposes a storage method of GML data for spatial database systems in order to solve the problems. The proposed method generates spatial database schemas from GML application schemas and store GML data into SDBMS through the generated schemas. A prototype of the storage method has been implemented on the Postgre SQ/SPE system to show the proposed method is appropriate for storing GML data. As a result, the implemented system was able to store various GML data which had diverse XML structures and different size. Stored data size was smaller than GML files. Furthermore, spatial, non-spatial, and mixed content queries could be performed over the stored GML data as quickly.