• Journal of Information Technology Applications and Management
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• 제14권3호
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• pp.49-77
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• 2007

Role-based access control (RBAC) models are recently receiving considerable attention as a generalized approach to access control. In line with the increase in applications that deal with spatial data. an advanced RBAC model whose entities and constraints depend on the characteristics of spatial data is required. Even if some approaches have been proposed for geographic information systems. most studies focus on the location of users instead of the characteristics of spatial data. In this paper. we extend the traditional RBAC model in order to deal with the characteristics of spatial data and propose new spatial constraints. We use the object-oriented modeling based on open GIS consortium geometric model to formalize spatial objects and spatial relations such as hierarchy relation and topology relation. As a result of the formalization for spatial relations. we present spatial constraints classified according to the characteristics of each relation. We demonstrate our extended-RBAC model called OOGIS-RBAC and spatial constraints through case studies. Finally. we compare our OOGIS-RBAC model and the DAC model in the management of access control to prove the efficiency of our model.

• 한국실내디자인학회논문집
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• 제21권6호
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• pp.100-108
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• 2012

Modern architecture tends to split the everyday life and the space of human. Position of architecture should be on the relationship between nature and human need. It will be study on the everyday life of architecture from architecture and everyday life of human relationships. Based on this study, it makes clear the visual aspects of architectural experience to acquire spatial tones for analyzing architectural Everyday-ness. In this case, Portugal's modern architectural space was impressing, because of the construction of local color and architectural vocabulary of the Everyday-ness. Therefore, the Everyday-ness of Architecture by relationship analysis reveals the space of these spatial tones. Spatial characteristics of the Everyday-ness of architecture be analyzed of simplicity, purity, locality, reminiscent, continuity, and transition, etc. Expression elements of spatial tones can be derived into five classes such as light, color, material, pattern (texture), and depth. In conclusion, spatial characteristics of the Everyday-ness and expression elements of spatial tones consist of configuration matrixes to analyze the spatial tones of the contemporary architecture in Portugal. As a result of this study, the expression characteristics of spatial tones of contemporary architecture in Portugal are background-ness, one-ness, and inherence. I hope this study will be applied to the basic data of the architectural Everyday-ness.

• 지적과 국토정보
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• 제50권2호
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• pp.81-100
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• 2020

본 연구는 풍수해로부터 발생 가능한 피해를 추정하기 위한 공간정보 DB 활용 방안과 공간정보의 품질 점검 기준을 제안하고자 하였다. 국가재난관리정보시스템, 국가공간정보통합체계 공개자료 목록을 대상으로 공간정보 DB 중 풍수해 피해 추정을 위해 활용될 수 있는 데이터를 피해유형별로 매핑하였으며, 해당 데이터를 활용하여 피해 분석을 위한 품질 점검 기준 항목을 제안하였다. 본 연구를 통해 풍수해 피해 추정을 위한 공간정보 DB 활용이 가능할 것이며, 품질 점검 기준을 통해 분석 결과의 신뢰성을 담보할 수 있을 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권12호
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• pp.4617-4632
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• 2021

IEEE 802.11ax is a protocol being developed for high-density Wireless Local Area Networks (WLAN). Several algorithms have been proposed to improve the level of spatial reuse applied in IEEE 802.11ax. However, these algorithms are tentative and do not specify how to select the transmit power and carrier sense threshold in practice; It is unclear when and why the tuned parameters lead to better network performance. In this paper, we restricted the scale of transmit power tuning to prevent the case of backfire in which spatial reuse will result in transmission failure. If the restrictions cannot be satisfied, spatial reuse will be abandoned. This is why we named the proposed scheme as Arbitration based Spatial Reuse (ASR). We quantified the network performance after spatial reuse, and formulate a corresponding maximum problem whose solution is the optimal carrier sense threshold and transmit power. We verified our theoretical analysis by simulation and compared it with previous studies, and the results show that ASR improves the throughput up to 8.6% compared with 802.11ax. ASR can avoid failure of spatial reuse, while the spatial reuse failure rate of existing schemes can up to 36%. To use the ASR scheme in practice, we investigate the relation between the optimal carrier sense threshold and transmit power. Based on the relations got from ASR, the proposed Relation based Spatial Reuse (RSR) scheme can get a satisfactory performance by using only the interference perceived and the previously found relations.

• International Journal of Contents
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• 제7권1호
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• pp.29-36
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• 2011

Gestures have been employed for human computer interaction to build more natural interface in new computational environments. In this paper, we describe our approach to develop a gesture interface using spatial context information. The proposed gesture interface recognizes a system action (e.g. commands) by integrating gesture information with spatial context information within a probabilistic framework. Two ontologies of spatial contexts are introduced based on the spatial information of gestures: gesture volume and gesture target. Prototype applications are developed using a smart environment scenario that a user can interact with digital information embedded to physical objects using gestures.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2008년도 한국컴퓨터종합학술대회논문집 Vol.35 No.1 (B)
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• pp.588-591
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• 2008

본 논문은 Data mining에서 선호도 분석 등에 사용되는 Skyline Query[2] 중 자료의 속성에 spatial한 성질이 있을 때 사용할 수 있는 Spatial Skyline Query[3] 문제에 대해 연구한다. 우선 Spatial Skyline 집합을 추출하기 위한 기존의 알고리즘의 문제점을 짚어보고 보다 개선된 알고리즘을 제시한다. 또한 전체 Spatial Skyline 집합이 아닌 그 중 더 의미 있을 수 있는 부분 집합을 좀 더 빠른 시간 복잡도에 구하는 방법 또한 제시한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.245-248
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• 2004

In this paper, we propose a framework for synchronization of spatial data between mobile devices and a server by using SyncML(Synchronization Markup Language) that is standard specification for synchronization protocol. We used GML (Geographic Markup Language) to support interoperability of spatial data between various data sources. We also used metadata and catalog service to access and integrate distributed spatial data, considering relationships of spatial data and non-spatial data.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제5권1호
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• pp.57-69
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• 2001

A new initiative in the 7th curriculum of mathematics is the inclusion of spatial sense in geometry. The purpose of this study is threefold: a) to identify the concepts of spatial sense; b) to systematize the contents of spatial sense by analysis the curricular and texbooks; and c) to explore an effective way of teaching-leaning of spatial sense.

• 한국데이타베이스학회:학술대회논문집
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• 한국데이타베이스학회 1997년도 International Conference MULTIMEDIA DATABASES on INTERNET
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• pp.472-482
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• 1997

Multi-dimensional data play a crucial role in various fields, as like computer graphics, geographical information system, and multimedia applications. Indexing method fur multi-dimensional data Is a very Important factor in overall system performance. What is proposed in this paper is a new dynamic access method for spatial objects called HL-CIF(Hierarchically Layered Caltech Intermediate Form) tree which requires small amount of storage space and facilitates efficient query processing. HL-CIF tree is a combination of hierarchical management of spatial objects and CIF tree in which spatial objects and sub-regions are associated with representative points. HL-CIF tree adopts "centroid" of spatial objects as the representative point. By reflecting objects′sizes and positions in its structure, HL-CIF tree guarantees the high spatial locality of objects grouped in a sub-region rendering query processing more efficient.

• 한국공간정보시스템학회 논문지
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• 제11권2호
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• pp.19-26
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• 2009

Ubiquitous service based on Spatio-temporal dataspaces requires not only the moving objects data but also the spatial objects. However, existing methods can not handle the moving objects and spatial objects together. To overcome the limitation of existing methods, we propose a new index structure called UIL (Union Indexing Lists) which contains two parts: MOL (Moving Object List) and SOL (Spatial Object List) to index the moving objects and spatial objects together. In addition, it can suppose the flexible queries on these data. We present the results of a series of tests which indicate that the structure perform well.