• International journal of advanced smart convergence
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• v.7 no.3
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• pp.61-65
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• 2018

A Location Register(LR) system manages each subscriber's location information, which continuously changes in mobile cellular network. For this purpose, the LR database system provides backup management facilities. The objectives of this paper are to identify the problems of the current LR system through rigorous analysis, to suggest solutions to them. I proposed efficient backup methods that takes into account the characteristics of LR database transactions. In the proposed backup method, I use two kinds of dirty flags in order to solve the performance degradation problem caused by frequent registration- location operations.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.854-859
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• 2002

Location Based Services, or LBS refers to value-added service by processing information utilizing mobile user location. With the rapidly increasing wireless internet subscribers and world LBS market, the various location based applications are introduced such as buddy finder, proximity and security services. As the killer application of the wireless internet, the LBS has preconsidered technology about location determination technology, LBS middleware server for various application, and diverse contents processing technology. This paper describes the open architecture for LBS platform ensuring interoperability among the wireless networks and various location-based application services and the functional requirements for the LBS platform. The LBS platform in a narrow sense provides a standard interfaces for location management and network management for location services as follows, positioning (location acquisition through network or/and handset), location managing, location based functions, profile management, authentication and security, location based billing, information roaming between carriers and the system monitoring independent to specific network or ISP/CPs(Content Providers).

• Journal of KIISE:Information Networking
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• v.32 no.2
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• pp.190-202
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• 2005

Mobile nodes are change their point of attachment dynamically such as networks deployed in aircraft, boats, trains, and cars. These mobile nodes move together and share the same nobility properties. Therefore, this paper addresses an efficient location management scheme based on collaboration of mobile nodes to a mobile network. We propose a scheme that combines multicast routing with Mobile IPv6 to support mobile network in the internet. This paper also tests the usefulness of our proposed method using analytical models and compares the results with our scheme and HMIPv6(Hierarchical Mobile IPv6) and Network Mobility(NEMO).

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.676-678
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• 2003

Recently, in according as rapid improvement of telecommunication markets and wireless internet technology, Location- Based Services (LBS) have been discussed as new 'Killer' application. The purpose of LBS is to determine location of user through mobile handset and to offer location information service to end-user. This paper has suggested an efficient transmission scheme of maps data as one of the important content services relating to data transmission of LBS in mobile environment. The basic system consists of three parts : (1) GIS (Geographic Information System) Server for storing, processing and handling map data, (2) Middleware Server for transmitting of map data by request of client, and (3) Client for requesting map data to Server and displaying them on handset. Also, in order to transmit map data, we are to expand WKB (Well Known Binary) in conformance to Simple Feature Specification of OGC (Open GIS Consortium), and increase efficiency of data transmission by developing trans mission data format to be able to transmit lightweight data and considering data compression technology.

• Journal of Multimedia Information System
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• v.3 no.4
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• pp.129-134
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• 2016

A routing protocol in mobile ad hoc networks is important, and a location based routing has attracted attention. We have proposed a method, in which plural mobile agents (MA) manage location information and construct a route and the number of MA dynamically changes depending on the network situation. However, the area where each MA manages is not always appropriate. This would increase the network load due to unnecessary split and mergence of MAs. To solve this problem, in this paper, we propose an enhanced method. In this method, the MA management area is properly determined based on distribution of nodes. From the performance evaluation, we show that the proposed method outperforms conventional methods in terms of packet delivery rate when network load is high.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2402-2414
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• 1996

Registration is the process by which a base station gets the information of location and status about mobile stations. Registration will become an increasingly important issue in mobile cellular communications, especially in microcellular system with the increase of location updating traffic. Four typesof registration schemes, which are specified in US standard IS-95 and Korean standard TTA-KO-0062, power up registration scheme, power down registration scheme, distance based registration scheme and zone based registration scheme, will be mainly used in the future. In this paper, we derive the combined cost of signaling traffic of paging and registration for various parameters of mobile stations behavior(unencumbered call duration, power up and down rate, velocity, etc.) then we present numerical results for the perfroamnce of four registration schemes. The size of location area is provided for optimal operation.

• Journal of Computing Science and Engineering
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• v.4 no.2
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• pp.173-187
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• 2010

Recent technological advances in mobile communication systems have made explosive growth in the number of mobile device users worldwide. One of the most important issues in designing a mobile computing system is location management of users. The hierarchical systems had been proposed to solve the scalability problem in location management. The scalability problem occurs when there are too many users for a mobile system to handle, as the system is likely to react slow or even get down due to late updates of the location databases. In this paper, we propose a top-down clustering algorithm for hierarchical location database systems in a wireless network. A hierarchical location database system employs a tree structure. The proposed algorithm uses a top-down approach and utilizes the number of visits to each cell made by the users along with the movement information between a pair of adjacent cells. We then present a modified algorithm by incorporating the exhaustive method when there remain a few levels of the tree to be processed. We also propose a capacity constraint top-down clustering algorithm for more realistic environments where a database has a capacity limit. By the capacity of a database we mean the maximum number of mobile device users in the cells that can be handled by the database. This algorithm reduces a number of databases used for the system and improves the update performance. The experimental results show that the proposed, top-down, modified top-down, and capacity constraint top-down clustering algorithms reduce the update cost by 17.0%, 18.0%, 24.1%, the update time by about 43.0%, 39.0%, 42.3%, respectively. The capacity constraint algorithm reduces the average number of databases used for the system by 23.9% over other algorithms.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.917-922
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• 2004

Mobile ad hoc networks (MANETs) are networks of mobile nodes that have no fixed network infrastructure. Since the mobile node's location changes frequently, it is an attractive area to maintain the node's location efficiently. In this paper, we present an adaptive randomized database group (ARDG) scheme to manage the mobile nodes mobility in MHANETs. The proposed scheme stores the network nodes' location in location databases to manage the nodes' mobility. When a mobile node changes its location or needs a node's location, the node randomly select some databases to update or que교 the location information. The number of the selected databases is fixed in the case of querying while the number of the databases is determined according to the node's popularity in the case of updating. We evaluated the performance of the proposed scheme using an analytical model, and compared the performance with that of the conventional randomized database group (RDG) scheme.

• Journal of Internet Computing and Services
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• v.2 no.5
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• pp.49-58
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• 2001

Mobile positioning measurement is the most important technology for Location Based Services in the cellular networks. Generally, we are expecting to use GPS to guarantee high accuracy of the mobile position, A CDMA network-based technique for the Mobile Station position calculation needs to be implemented in the cdma2000 network whether the handsets have GPS or not, The most reliable methods of the network-based location technologies are based on the estimation of time of signal traveling between MS and B18 in a network whose coordinates are identified, Other signal parameters such as the power of the received signal and the signal arrival direction cannot be used as main data for a location system because adoption of only the signal parameters will not meet the FCC requirements, In practice, the estimates of the time of signal propagation between MS and BTS always have errors resulting from low-resolution power of measurements and multi path signal propagation, This paper describes the combined network-based location technology in the cdma2000 1× necessary to meet US FCC requirements. The issues of a calibration table and statistic processing based on the pilot strength as well as combined network-based location technologies(TOA/ TDOA) will help to achieve higher location accuracy than specified in the US FCC Rule.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.3
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• pp.1-11
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• 2013

This study developed the algorithm of location-based service for supplying the efficient tourism service to traveller using mobile device and applied it to the Jeonju HANOK village. First, the location service was advanced using algorithm coupling with GPS error range and travel speed in single line, and with GPS location and nearest neighbor method to line in multiple one. Also this study developed a program using DuraMap-Xr spatial engine for establishing topology to Node and Link in line automatically. And the foundation was prepared for improving travel convenience by programming location-based service technology to single and multiple lines based on Blackpoint-Xr mobile application engine.