• Journal of the Korean Association of Geographic Information Studies
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• v.1 no.2
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• pp.67-79
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• 1998

Most GIS applications are read-intensive on a large number of spatial objects and when the spatial objects are composite objects, the contained objects within the composite objects are also accessed. In GIS applications, creation, deletion, and update operations on spatial objects occur very rarely, but once they occur they deal with a large number of spatial objects. This paper proposes the concept of the multi-level pre-fetch query to retrieve a large number of spatial objects efficiently, and the functionality of the deferred-flush on the newly created persistent objects into the database with the optimal performance, and presents the design and implementation details of those ideas into an object-oriented DBMS BADA-III while considering these characteristics of GIS applications. The multi-level pre-fetch query retrieves the objects that satisfy the query and the objects that are contained within the objects up to the level specified by users, and registers the retrieved objects on the client cache. The deferred-flush flushes a large number of composite objects that are created by the application with a minimal overhead of the server and a minimal number of communications between the client and the server. These two functionality are suitable for the applications that search or create a large number of composite objects like GIS applications.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.268-271
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• 2004

Today, the vehicle is used the mean of transportation as well as the mobile office with the third digital life space. So telematics is an emerging industry that has tremendous future potential. It is necessary the essential contents for telematics services : navigation map for navigation, POI, real-time traffic information etc. In this paper, we proposed the telematics contents server to manage the telematics contents with efficient performance in distributed environment. The telematics contents server transforms and stores the essential contents and provide it to user through standard interface. The telematics contents server is middleware to offer a rapid essential telematics contents management, client connectivity, and communications. It is useful for the telematics service provider to build telematics system under distributed environment.

• The KIPS Transactions:PartD
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• v.8D no.3
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• pp.193-202
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• 2001

Currently, the components of the GIS have been physically run on a stand-alone system. With rapid advances in internet technology, GIS users require that they are able to not only access they heterogeneous and remote GIS database as well as their own information, but also share them. However, these GIS have the defects that can not handle formats different from own data format. Therefore, in this paper, we propose to integrate the components of the heterogeneous and remote GIS using CORBA in order to solve these problems, which is a distributed object technology, the mediator and wrapper technology in client and server layers.

• The KIPS Transactions:PartD
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• v.10D no.3
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• pp.359-366
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• 2003

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, selective deletion of objects, cache compaction and object structuring step in the clients. The conversion is a time- intensive operation due to limited resources of mobile phones such as low computing power, small memory. Therefore, in order to control the map efficiently in the vector map service based mobile phones, it is necessary to study the methods which reuse cached objects for reducing wireless network bandwidth and overwhelming the limited resources of mobile phones as well. This paper proposes the methods of reusing pre-received spatial objects for map control in the mobile vector map service system based on client-server architecture. The experiments conducted on the Web GIS systems with real data show that the proposed method is appropriate to map services for mobile phone. We also analyze the advantages and drawbacks between the reuse of cached data and transmission of raw data respectively.

• Spatial Information Research
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• v.9 no.2
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• pp.207-225
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• 2001

This study develops a GIS-based system which examines the adequacy of the Groundwater development project before the actual designing of the project. A system environment is constructed in order to efficiently and scientifically manage and analyze data related to Groundwater through a Server/Client environment. For this programs such as GIS S/W ArcVies3.2, RDBMS ORACLE, ArcSDE (Spatial Database Engine) are used. WHPA and AQTESOLV are employed as a underground water simulation program and Scripts, a language for ArcView, is used to develop graphic user interface (GUI). Using the system developed here, we can transfer simulation results obtained by WHPA regarding Groundwater levels in new development projects into GIS. We can also judge whether a Groundwater development project should be permitted through examining overlaps of th effects of the development and comparing with o pollutants. At the same time, the system has a feature of supporting Groundwater development and based designing through judging the proper amount of Groundwater in a new project. It is also possible to easily and quickly prepare charts and reports using the outputs of the system. Since a two-tiered system which shares DB using inter-and intranets is developed, all the departments in the ministry of agriculture and forest and the agriculture base corporation can share accurate, reliable and latest information related to Groundwater.

• Proceedings of the Korea Multimedia Society Conference
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• 2002.05d
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• pp.1056-1061
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• 2002

지리정보시스템은 이미 우리 생황의 많은 분야에서 활용되고 있으며, 점차 그 활용 범위가 확대되어 가고 있다. 이러한 지리정보시스템을 WWW 환경에서 구축함으로써 웹 브라우저만 있으면 누구나 쉽게 지리정보시스템을 접할 수 있게 되었다. 본 논문에서는 지리정보시스템과 같이 많은 데이터를 처리하기에는 속도상의 문제가 발생할 수 있기 때문에, 이를 해결하기 위한 방법으로 Client/Server 설계, GIS-Engine 설계, 위치 검색 시스템 설계, 수직 분할 구조의 설계 등 Web 기반의 지리정보시스템의 설계 기법을 고찰해 보고, 이들 설계 기법을 이용한 관광지리정보시스템을 설계해 보았다. 앞으로 계속된 연구를 통하여 이를 구현하여 Web-GIS를 관광분야에 활용할 수 있도록 할 것이며, Web-GIS가 단지 지리정보의 검색시스템으로 한정하지 않고 응용 범위를 확대하여 다양한 분야에서 활용될 수 있도록 노력하겠다.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.219-221
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• 2003

With regarding to web GIS, OGC promotes WFS allowing a client to retrieve geospatial data encoded in GML which is a modeling language to encode the semantics, syntax and schema of geospatial information resources. Even though GML provides benefits for geographic description, it is too heavy to be processed by mobile devices. In order to address the issue, this paper evaluates GML service with WFS server and GML viewers. Through this paper, we get analyses of properties of GML geospatial data and the effects on wireless devices, which are expected to be fundamental materials onto a design of mobile applications.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.7
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• pp.75-80
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• 2009

In this study, a Web server was constructed using LabVIEW's DataSocket, which makes possible acquisition, analysis, and saving in real time. The output value of the optical current sensor at the web server PC was measured and the output value was displayed using the Web browser of the client PC. DataSocket by LabVIEW makes the construction of a Web server easier than other languages and is compatible with other application programs. An optical current sensor was composed using a 1310 [nm] laser diode, and 9/125 [${\mu}m$] standard single mode optical fiber and was created to be a close type sensor. Data measurement using Web servers has the advantage of monitoring electric power systems at a great distance and can fuse IT technology and electric power systems. Also, this measurement uses inexpensive mounting and programming when compared to existing measurement equipment allowing the construction of a measurement system in any situation or surrounding.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.153-158
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• 1998

Since the mid-1990′s, researches on 3D GIS have been regarded as one of main issues both in the academic sites and commercial vendors; recently, some prototyped systems or the first versioned software systems of commercial basis are being reported and released. Unlike conventional 2D GIS, which consists in intelligent structured GIS or desktop GIS, every 3D GIS has its own distinguished features according to data structure-supporting capability, GIS-styled functionality, external database accessibility, interfacing extents with 2D GIS, 3D visualization/texture mapping ability, and so forth. In this study, technical aspects related to system development, SERI-Web3D GIS ver. 1.2, are explained. Main features in this revised 3D GIS can be summarized: 2-tier system model(client-server), VGFF(Virtual GIS File Format), internal GIS import, Feature manager(zoning, layering, visualization evironment), Scene manager(manage 3D geographic world), Scene editor, Spatial analyzer(Intersect, Buffering, Network analysis), VRML exporter. While, most other 3D GISes or cartographic mapping systems may be categorized into 3D visualization systems handling terrain height-field processing, 2D GIS extension modules, or 3D geometric feature generation system using orthophoto image: actually, these are eventually considered as several parts of "real 3D GIS". As well as these things, other components, especially web-based 3D GIS, are being implemented in this study: Surface/feature integration, Java/VRML linkage, Mesh/Grid problem, LOD(Level of Detail)/Tiling, Public access security problem, 3-tier architecture extension, Surface handling strategy for VRML.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.2
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• pp.263-268
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• 1997

Software structure must be dynamic to support new geospatial information sources and their object-oriented implementation on the Web. JAVA is interactive, platform idependent and object-oriented language and meets all needs on Internet GSIS. This paper introduce JAVA based GIS program to manipulates various geographic data on Internet, communicating interactively and transfer real-time data between server and client. This and this program analysis roof detector in all part of Pusan area and indicates the traffic states, road surface conditions, weather information, shortest cut, and road names in JAVA client windows. Also this study shows various techniques in expression real time traffic informations.