• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.6
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• pp.1-16
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• 2012

In this paper, we propose a cost-effective location and service management scheme in LTE (Long Term Evolution) networks, which a per-user service proxy is created to serve as a gateway between the mobile user and all client-server applications engaged by the mobile user. The service proxy is always co-located with the mobile user's location database such that whenever the MU's location database moves during a location hand-off, a service hand-off also ensues to co-locate the service proxy with the location database. This allows the proxy to know the location of the mobile user all the time to reduce the network communication cost for service delivery. We analyze four integrated location and service management schemes. Our results show that the centralized scheme performs the best when the mobile user's SMR (service to mobility ratio) is low and ${\upsilon}$(session to mobility ratio) is high, while the fully distributed scheme performs the best when both SMR and ${\upsilon}$ are high. In all other conditions, the dynamic anchor scheme is the best except when the service context transfer cost is high under which the static anchor scheme performs the best. Through analytical results, we demonstrate that different users with vastly different mobility and service patterns should adopt different integrated location and service management methods to optimize system performance.

• Journal of KIISE:Information Networking
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• v.35 no.3
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• pp.183-191
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• 2008

In this paper, we propose Stream Control Transmission Protocol(SCTP) proxy which supports making an SCTP connection from a Corresponding Node(CN) to a Mobile Node(MN). Recently, mobility support in transport layer is proposed, which provides mobility in end-to-end way using the extension of SCTP. Mobile SCTP can provide handover to all applications that use SCTP as a transport protocol. However, current SCTP does not include independent location management service and can not make connection from a CN to a MN without assistance of other mobile protocols. To solve this problem, Proposed SCTP proxy interoperates with generic location management service and performs an address transformation to forward connection set up messages to the MN. Using the proposed proxy, SCTP can provide a complete mobility support including a connection setup to the MN and maintaining an existing connection.

• The Transactions of the Korea Information Processing Society
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• v.6 no.4
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• pp.1032-1044
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• 1999

In the mobile communication systems such as PCS(Personal Communication Service), several strategies have been proposed to optimize the signalling traffic load by using the characteristics of traffic and mobile patterns for effective mobility management. According to IS-41 standard, LA(Location Area) consists of static and arbitrarily-defined set of cells, which do not take into account mobility patterns of mobile stations. In this paper, we propose an improved location management mechanism which contains the neighbor cells of the LA selectively using the mobility history of a mobile station and accommodates the LA size adaptively according to the speed of the mobile station. Also, we use the paging priorities for cells in LA to improve the paging efficiency. We compare the performance of conventional mechanism with that of the proposed mechanism using numerical analysis. The analysis results show that the proposed location management mechanism is better than conventional mechanism significantly.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1588-1596
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• 2004

Recently, many WMS(Web Mapping Services) and POI(Point of Interest) service on to be in service on the Internet using Web CIS(Geographic Information System) as information Technology and computer HW are evolved faster in its speed, network bandwidth and features. The Web GIS is, however, limited and constrained on the specification of its system configuration, the service class provided and the presentation methodology of a map. As the mobile Internet becomes popular in mobile service, Web GIS service on mobile environment is strongly required and to be provided by LBS(Location Based Service) on a mobile client such as PDA with location information of the user. In this paper, we made an effort to design and implement a GIS computing environment by thin client for mobile web mapping service. For implementing the thin client GIS computing environment, we were using NGII's(National Geographic Information Institute's) DXF map, representing the map by SVG(Scalable Vector Graphics) recommended by OGC(OpenGis Consortium), and adapting standard XML web service to provide the thin client GIS service on PDA by applying the location information of the user in realtime with GPS on mobile environment.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.800-801
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• 2017

Location-based services (LBS) are used in various applications such as emergency support, navigation, location, traffic routes, information gathering, and entertainment due to the rapid growth of information communication technologies and mobile phones. In general, locations are represented by coordinates and are related to terrain. These are of great interest in mobile-based data transmission. This paper proposes a method to exchange the contact of the other party by detecting the movement of the mobile phone of the individual user based on the location-based service. The proposed method extracts motion using the acceleration sensor of the mobile phone and transmits the location and time information to the server when the motion continues for a predetermined time. Attempts to establish a connection between users who are experiencing motion in mobile phones in the short distance have been made from the server. Once the connection between the users is made, the encrypted contact is received from the server. Experimental results show that the proposed method can exchange data by minimizing the processing in the handset compared with the existing method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.9
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• pp.1193-1201
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• 2020

Cell planning, which determines the cell structure for location management of mobile terminals in mobile communications, has been dealt with as an important research task to determine network performance. Among the factors influencing the cell structure planning in mobile communication, the signal cost for location management plays the most important role. In this paper, we propose an optimization algorithm that minimizes the location management cost of all the cells used to plan the cell structure in the network with reporting cell structure in mobile communication. The proposed algorithm uses a Tabu search algorithm, which is a meta-heuristic algorithm, and the proposed algorithm proposes a new neighborhood generation method to obtain a result close to the optimal solution. In order to evaluate the performance of the proposed algorithm, the simulation was performed in terms of location management cost and algorithm execution time. The evaluation results show that the proposed algorithm outperforms the existing genetic algorithm and simulated annealing.

• International Journal of Control, Automation, and Systems
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• v.4 no.2
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• pp.204-216
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• 2006

Latest advances in hardware technology and state of the art of mobile robot and artificial intelligence research can be employed to develop autonomous and distributed monitoring systems. And mobile service robot requires the perception of its present position to coexist with humans and support humans effectively in populated environments. To realize these abilities, robot needs to keep track of relevant changes in the environment. This paper proposes a localization of mobile robot using the images by distributed intelligent networked devices (DINDs) in intelligent space (ISpace) is used in order to achieve these goals. This scheme combines data from the observed position using dead-reckoning sensors and the estimated position using images of moving object, such as those of a walking human, used to determine the moving location of a mobile robot. The moving object is assumed to be a point-object and projected onto an image plane to form a geometrical constraint equation that provides position data of the object based on the kinematics of the intelligent space. Using the a priori known path of a moving object and a perspective camera model, the geometric constraint equations that represent the relation between image frame coordinates of a moving object and the estimated position of the robot are derived. The proposed method utilizes the error between the observed and estimated image coordinates to localize the mobile robot, and the Kalman filtering scheme is used to estimate the location of moving robot. The proposed approach is applied for a mobile robot in ISpace to show the reduction of uncertainty in the determining of the location of the mobile robot. Its performance is verified by computer simulation and experiment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2B
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• pp.148-158
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• 2011

Stationary nodes and mobile nodes co-exist wireless sensor network(WSN) can provide variety of new services. The stationary sensor node acts not only the gathering the environmental sensing data but also a access point to bidirectional communication with numerous mobile sensor nodes(mobile node), and the mobile sensor nodes are installed inside mobile objects and identify the location in real-time and monitor the internal status of the object. However, only using the legacy WSN protocol, it is impossible to set up the stable network due to the several reasons caused by the free-mobility of the mobile nodes. In this paper, we suggest three methods to increase the hit-ratio of the asynchronous message delivery(AMD) among mobile nodes. We verified the performance of the suggested methods under the stationary-mobile co-existed WSN testbed.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.3
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• pp.43-58
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• 2008

In this paper, we have presented a dynamic, predictive location update scheme that takes into account each user's mobility patterns. A user's past movement history is used to create two-dimensional transition probability matrix which makes use of two directional consecutive location areas. A mobile terminal utilizes the transition probability to develop a predictive path which consists of several predictive nodes and then the location update is saved as long as a mobile user follows the predictive path. Using continuous-time Markov chain, cost functions of location update and paging are derived and it is shown that the number of predictive nodes can be determined optimally. To evaluate the proposed scheme, simulations are designed and the numerical analysis is carried out. The numerical analysis features user's mobility patterns and regularity, call arrival rates, and cost ratio of location update to paging. Results show that the proposed scheme gives lower total location management cost, compared to the other location update schemes.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.7 s.337
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• pp.1-6
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• 2005

Now that the reduction of the cell size in order to serve the increasing subscribers has raised the frequency of the location update, it has increased the cost of location management. In this paper, we show that the location management strategy based on the call arrival probability(CAP) can reduce the cost of the location management by analyzing that cost in this strategy which was proposed in [1] to reduce the cost of the location management in mobile communication. And we compare the location management cost by analyzing with that by simulating.