• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.13-21
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• 2011

In mobile environment supporting mobility technologies, user requirements have been increased with respect to utilization of location information. In particular, moving object DBMS has consistently posed in order to efficiently maintain traffic information related to location of vehicle which tents to tremendously change over time. Despite the fact that these sorts of researches must be taken into consideration, empirical studies on moving object in terms of map database for lbs service, spatial attribute of which is continuously changed over time, have rarely performed. Therefore, aim of this paper is to suggest efficient spatial index scheme, which is capable of supporting query processing algorithm and location of moving object over time, by developing new empirical model. As a result, we can come to the conclusion that moving object model based on multi-fixed grid index makes it possible to cut down on the number of entity for retrieving. What's more, this model enables hierarchical data to be accessed through efficient spatial filtering on large-scale lbs data and constraints in accordance with level in order to display map.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.3
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• pp.452-458
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• 2002

Although the reuse of the cached data for scrolling the map reduces the amount of passed data between client and server, it needs the conversions of data coordinates, selertive deletion of objects and cache compaction at client. The conversion is time intensive operation due to limited resources of mobile phones such as low computing power, small memory. Therefore, for the efficient map control in the vector map service based mobile phone, it is necessary to study the method for reducing wireless network bandwidth and for overwhelming the limited resources of mobile phone as well. This paper proposes the methods for racking pre-received spatial objects in client-server systems for mobile CIS. We also analyze the strengths and drawbacks between the reuse of cached data and transmission of raw data respectively.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.1
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• pp.26-35
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• 2009

This paper will propose the efficient method that should be designed to utilize the design pattern of GoF(Gang of Four) for implementation of LBS(Location Based Service) mobile system. The design method proposed by this paper can design and implement system interface using creational patterns, structural patterns and behavioral patterns of design pattern from the user and mobile system viewpoint. The design method using design pattern can show increasing reusability of module and software, abridging the development time, minimizing the maintenance and decreasing the efficiency of memory of system to software development. Therefore, we used a design pattern in order to change the middleware applying geographic information system from mobile environment. Finally, the mobile system applied to design pattern shall contribute to showing high stability and reliability, improving reusability and scalability of module and software and developing efficient LBS mobile system.

• Journal of Korea Spatial Information System Society
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• v.5 no.2 s.10
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• pp.69-82
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• 2003

Mobile transactions updating spatial objects are long transactions that update local objects of mobile clients during disconnection. Since a recovered transaction cannot read the write sets of other transactions committed before the recovery due to disconnection, the recovered transaction may conflicts with them. However, aborting of the recovered long transaction leads to the cancellation of all updates including the recovered updates. It is definitely unsuitable to cancel the recovered updates due to the conflicts. In this paper, we propose the recovery scheme to retrieve foreign conflictive objects from the write sets of other transactions for reducing aborting of a recovered transaction. The foreign conflictive objects are part of the data committed by other transactions and may conflict with the objects updated by the recovered transaction. In the scheme, since the recovered transaction can read both the foreign conflictive objects and the recently checkpoint read set, it is possible to reupdate properly the potentially conflicted objects.

• Journal of Korea Multimedia Society
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• v.11 no.7
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• pp.1025-1034
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• 2008

In this paper, we developed GridGML for efficiently supplying a GML and visualizing the map with partitioning map and caching method to a mobile device. In order to overcome the weighting of a file, which is the biggest weakness of a GML, GridGML extracts only the most necessary parts for the visualization of the map among GML attributes, and makes the file light as a class instance by applying an offset value. GridGML manages a partition based on the visualization area of a mobile device to visualize the map to a mobile device in real time, and transmits the partition area by serializing it for the benefit of transmission. Also, the received partition area is compounded in a mobile device and is visualized by being partitioned again as four visible areas based on the display of a mobile device. Then, the area is managed by applying a caching algorithm in consideration of repetitiveness for a received map for the efficient operation of resources. Also, in order to prevent the delay in transmission time as regards the instance density area of the map, an adaptive map partition mechanism is proposed for maintaining the transmission time uniformly.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.319-321
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• 2005

최근 효율적인 교통 흐름 제어 및 교통정보 서비스 제공을 위한 ITS(Intelligent Transport System)에 대표적인 서비스로는 수집된 정보를 바탕으로 도로의 소통정보를 모니터링하고 이용자들에게 웹이나 지역에 설치된 VMS를 통해 정보를 제공하는 것이라 할 수 있다. 그러나 이러한 서비스를 위한 GIS가 OpenGIS와 같은 표준화 단체에서 제안하고 있는 구조를 따르지 않고 있으며, 지리정보의 표현도 검증 없이 자체적으로 GIS정보를 이용함으로 인해 서비스의 성능과 품질 저하는 물론 정보통합의 어려움을 가지고 있다. 본 논문에서는 OpenGIS에서 공간정보 표현에 권고되고 있는 GML을 기반으로 도로망에 구축되어진 각종 교통정보 기기로부터 ITS로 수집된 실시간 교통정보를 이용하여 데이터베이스를 구축하고, 이를 반영하여 모바일 기기 또는 웹서비스를 통해 교통상황을 모니터링 할 수 있는 시스템을 제안하고자 한다. 제안된 시스템은 GML을 기반으로 한 지리정보 DB와 각종 교통정보 기기로부터 수집된 실시간 교통정보의 통합을 통해 모바일 기기나 웹을 통해 공통적으로 서비스를 제공할 수 있는 Client/server 시스템에 주안점을 두고 설계하였다. 본 연구에서 설계된 시스템은 전용 공간데이터를 구축하지 않고, 표준화된 공간정보인 GML을 이용한 변환 메커니즘을 통하여 서비스를 제공함으로써 비용과 시간을 절약할 수 있으며, 이 기종의 시스템에 서비스가 가능하도록 하였다.

• Spatial Information Research
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• v.13 no.4 s.35
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• pp.355-364
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• 2005

Vector data sets (e.g. maps) are currently major sources of displaying, querying, and identifying locations of spatial features in a variety of applications. Especially in mobile environment, the needs for using spatial data is increasing, and the relative large size of vector maps need to be smaller. Recently, there have been several studies about vector map compression. There was clustering-based compression method with novel encoding/decoding scheme. However, precedent studies did not consider that spatial data have to be updated periodically. This paper explores the problem of existing clustering-based compression method. We propose an adaptive approximation method that is capable of handling data updates as well as reducing error levels. Experimental evaluation showed that when an updated event occurred the proposed adaptive approximation method showed enhanced positional accuracy compared with simple cluster based compression method.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.451-456
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• 2003

최근 대부분의 대규모로 추진되는 공공 서비스 목적이나 민간 사용 목적의 공간정보 구축 및 시스템 개발 분야는 실제 데이터베이스 구축이나 기술 개발에 앞서 ISP(정보화 전략계획: Information Strategy Planning)의 수립을 선행하는 경우가 일반적이다. 본 연구는 2000년부터 추진중인 한국전자통신연구원의 4S 기술개발 사업에 선행하여 수행된 4S 연계기술지원 사업의 ISP에 포함된 주요 기술사양을 분석하고, 분석 결과에 대하여 급속히 변화하고 있는 4S 관련 정보 기술동향을 반영함으로서 국내 상황에 적합하고 향후 사업에도 적용이 가능한 확장 모델로 제시하는 것을 목적으로 한다. 기본적으로 4S 기술개발 사업은 GIS-SIIS-GNSS-ITS 등 공간정보를 대상으로 하거나 주요 정보자원으로 이용하는 분야의 연계 기술을 컴포넌트 기반으로 개발하고, 개발된 컴포넌트에 대해서는 컴포넌트의 통합 또는 조립과 시험 검증과정을 통하여 국내외에서 전개되고 있거나 추진중인 다양한 공간정보 관련 사업에 적용 가능하도록 하는 것을 목적으로 하고 있다. 이러한 성과로 4S 기술개발 사 4S 모바일 컴포넌트 개발등과 같은 단위사업을 중심으로 소개되고 있었으나 이러한 단위 사업의 도출과정이나 추진 전략 또는 컴포넌트 연계 또는 재사용 과정등에 대하여는 체계적으로 알려진 경우가 거의 없다. 따라서 본 연구에서는 이러한 부문에 대한 내용을 기술적인 측면에서 분석하고, 이를 보다 확대하여 4S 컴포넌트 기반 단위 사업의 활용 가능성을 발전시킬 수 있는 확장된 아키텍처의 정립 과정으로 수행되고 있다.

• Journal of the Korea Society of Computer and Information
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• v.17 no.5
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• pp.93-101
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• 2012

In the field of urban planning and disaster prevention, various geographical information systems (GIS) and design softwares have been in use. Recently urban planners and disaster managing officials face new challenges, as three dimensional GIS, web environment, and smart phone app are rapidly developed. Technical progress in open API and mashup opens a possibility of making the citizen participation-based smart phone applications in the field of urban planning and disaster prevention. Our suggested smart phone applications will have technical, economic, and administrative impacts on the society in general; and play an effective role in developing U-City, U-health, and disaster prevention.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.180-194
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• 2017

Agricultural hazards management technology, which would allow individual farms to respond preemptively, has been developed. A preliminary system developed in the previous study provides precise weather forecasts by farms, notification of weather hazards by crops and delivery of response guidelines (http://www.agmet.kr). Although the GIS map-based alarm system has been implemented for a number of farmers and their farms, its user interface was not designed for individual users who seek information at their farms. In this study, we have developed a mobile application to provide early warnings of weather hazards up to 10 days in advance. A set of information including field-specific weather, crop growth stages and weather hazard alerts can be delivered to individual farmers through their mobile phone. This would guide users to access the map-based system using their smartphone to obtain field-specific weather information by the growth stage of cultivated crops. This would help the farmers make the better use of the existing weather-hazard GIS map-based alarm system.