• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.3
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• pp.1-10
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• 1995

In this paper, a fault-tolerant Mini-MAP system with high reliability is proposed. For fault-tolerance, the LLC sublayer, MAC sublayer, and physical layer of the Mini-MAP system are dualized. The detection of faults, the replacement of the failed network, and the management of the network are three major functions required for the dualization, and they are performed by ESM(Error Supervisory Machine), EMM(Error Management Machine), and NMM(Network Management Machine) of the proposed fault-tolerant Mini-MAP system, respectively. The ring maintenance function of the MAC sublayer is used for the detection of the faults. In the proposed fault-tolerant Mini-MAP system, the data are received from both of the dualized networks and transmitted to the selected one of the two. We analyze the reliability and the MTTF(Mean Time To Failure) of the proposed fault-tolerant Mini-MAP system and show that it has better performance compared to a general Mini-MAP system.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.19-30
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• 2009

The service that has recently come into the spotlight utilizes the map to first approach the map and then provide various mash-up formed results through the interface. This service can provide precise information to the users but the map is barely reusable. The sketch-map system of this paper, unlike the existing large map system, uses the method of presenting the specific spot and route in XML document and then clustering among sketch-maps. The map service system is designed to show the optimum route to the destination in a simple outline map. It is done by renovating the spot presented by the map into optimum contents. This service system, through the process of analyzing, splitting and clustering of the sketch-map's XML document input, creates a valid form of a sketch-map. It uses the LCS(Longest Common Subsequence) algorithm for splitting and merging sketch-map in the process of query. In addition, the simulation of this system's expected effects is provided. It shows how the maps that share information and knowledge assemble to form a large map and thus presents the system's ability and role as a new research portal.

• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.709-715
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• 2010

This paper represents a map building and localization system for mobile robot. Map building and navigation is a complex problem because map integrity cannot be sustained by odometry alone due to errors introduced by wheel slippage, distortion and simple linealized odometry equation. For accurate localization, we propose sensor fusion system using encoder sensor and indoor GPS module as relative sensor and absolute sensor, respectively. To build a map, we developed a sensor based navigation algorithm and grid based map building algorithm based on Embedded Linux O.S. A wall following decision engine like an expert system was proposed for map building navigation. We proved this system's validity through field test.

• Journal of Korea Multimedia Society
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• v.22 no.4
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• pp.417-423
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• 2019

This paper presents an evaluation system to determine the completeness of a space map obtained by a visual SLAM(Simultaneous Localization And Mapping) algorithm. The proposed system consists of three parts. First, the proposed system detects the occurrence of loop closing to confirm that users acquired the information from all directions. Thereafter, the acquired map is divided with regular intervals and is verified whether each area has enough map points to successfully estimate users' position. Finally, to check the effectiveness of each map point, the system checks whether the map points are identifiable even at the location where there is a large distance difference from the acquisition position. Experimental results show that space maps whose completeness is proven by the proposed system has higher stability and accuracy in terms of position estimation than other maps that are not proven.

• ETRI Journal
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• v.33 no.4
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• pp.476-486
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• 2011

The quality of navigation service is determined by the accuracy of the available data. For existing navigation services, a full map update is provided in order to keep the map data of mobile devices current. As content and services of mobile devices have recently been diversifying, the size of map data managed in mobile devices has increased, reaching several gigabytes in size. It generally takes tens of minutes to write several gigabytes of data into mobile device storage. For traditional navigation systems, a complicated storage structure called a physical storage format (PSF) is used to assure maximum processing performance of map data in mobile devices within limited resources. Consequently, even though modified navigation map data actually affects only a portion of a map, the full map data is updated because partial updates are not possible. In this paper, a navigation system is studied to solve this difficult partial map update problem. The map air update navigation system, which is the result of this study, provides real-time partial map updating using wireless communications.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2009.04a
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• pp.75-78
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• 2009

As a digital map is tile based of 2D, it is difficult to be satisfied with accuracy and up-to-date. In this study, we analyzed requirements of an object-oriented continuous digital map and designed the system. The digital map is 3D continuous object and has the accuracy and up-to-date, and designs with management system, transfer system, change information management system, frequent updating system and, same time updating system.

• The Journal of Korea Robotics Society
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• v.1 no.2
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• pp.117-124
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• 2006

In this paper, we develope the navigation system for patrol robots in indoor environment. The proposed system consists of PDA map modelling, a localization algorithm based on a global position sensor and an automatic charging station. For the practical use in security system, the PDA is used to build object map on the given indoor map. And the builded map is downloaded to the mobile robot and used in path planning. The global path planning is performed with a localization sensor and the downloaded map. As a main controller, we use PXA270 based hardware platform in which embedded linux 2.6 is developed. Data handling for various sensors and the localization algorithm are performed in the linux platform. Also, we implemented a local path planning algorithm for object avoidance with ultra sonar sensors. Finally, for the automatic charging, we use an infrared ray system and develop a docking algorithm. The navigation system is experimented with the two-wheeled mobile robot using North-Star localization system.

• Journal of Software Engineering Society
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• v.25 no.4
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• pp.63-67
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• 2012

According to the growth of data being generated in man fields, a distributed programming model MapReduce has been introduced to handle it. In this paper, we build two cluster system with Solaris and Linux environment on SUN Blade150 respectively and then to evaluate the performance of a MapReduce application running on MapReduce middleware Hadoop in terms of its average elapse time and standard deviation. As a result of this experiment, we show that the overall performance of the MapReduce application based on Hadoop is affected by the configuration of the cluster system.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.31-36
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• 1992

This paper describes the development of a 'General-purpose ETRI MAP interface module' (GEM) for a Mini-MAP network. GEM operates as a Mini-MAP node in our FA system. To communicate between GEM and programmable devices such as PLC, CNC, and robot, RS232C is used, which is a traditional method. A Mini-MAP host system controls and monitors programmable devices via GEM. The Mini-MAP function of GEM is implemented and tested on the basis of the MAP V3.0.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.311-313
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• 2010

This study is on the adapting vehicle-based mobile mapping system to the frequent unscheduled revision of 1:5000 scale national base map. We analyzed map layers which could be built by vehicle-based mobile mapping systems and studied surveying methods for each layers. Also, the methods of maintain surveying accuracy to satisfy accuracy standards of national base map were suggested. The maps of Yeouido, Hyangnam, and Suwon area were revised by vehicle-based mobile mapping system on a trial bases and possibility of utilizing vehicle-based mobile mapping system for map revision was analyzed. As a results it was revealed that vehicle-based mobile mapping systems were adequate for a irregular revision of national base map.