• Journal of Korea Spatial Information System Society
• /
• v.5 no.1 s.9
• /
• pp.13-25
• /
• 2003

The advent of LBS is caused by mobility advantage of wireless internet. The mobility has the information such as location which is based on LBS(Location based Services). It comes out as a killer application for wireless internet when market of wireless internet is diffused. In this paper, we build up the technical model and survey the requirement of technologies related LBS expanded as wireless internet services rapidly. First, we construct the conceptual model for LBS based on functions of LBS and characteristics of foreign models. This model is consisted of generalized components of LBS and can be used as a basic model to survey the requirement of each technologies. Second, we survey the demand of each technology for LBS. Then we analyze the importance of technologies for LBS to prepare developing various LBS. From this research, we can introduce proper plans and policy for LBS to develop technology stepwise, to promote industry activities and how to make up the foundation for LBS by government.

• Journal of KIISE:Information Networking
• /
• v.35 no.3
• /
• pp.183-191
• /
• 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 Journal of the Korea institute of electronic communication sciences
• /
• v.7 no.2
• /
• pp.391-399
• /
• 2012

This paper proposes a particle filter approach for SLAM(Simultaneous Localization and Mapping) of a mobile robot. The SLAM denotes estimation of both the robot location and map while the robot navigates in an unknown environment without map. The proposed method estimates robot location simultaneously with the locations of the ultrasonic beacons which constitute landmarks for navigation. The particle filter method represents the locations of the robot and landmarks in probabilistic manner by the distribution of particles. The method takes care of the uncertainty of the landmarks' location as well as that of the robot motion. Therefore, the locations of the landmarks are updated including uncertainty at every sampling time. Performance of the proposed method is verified through simulation and experiments. The method yields practically useful mapping information even if the range data from the landmarks include random noise. Also, it provides more accurate and robust estimation of the robot location than the usual least squares methods or dead-reckoning method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.4B
• /
• pp.647-658
• /
• 2010

Many localization schemes estimate the locations of radio nodes based on the physical locations of anchors and the connectivity from the anchors. Since they only consider the knowledge of the anchors without else other nodes, they are likely to have enormous error in location estimate unless the range information from the anchors is accurate or there are sufficiently many anchors. In this paper, we propose a novel localization algorithm with the location knowledge of anchors and even one-hop neighbors to localize unknown nodes in the uniform distance from all the one-hop neighbors without the range information. The node in the uniform distance to its all neighbors reduces the location error relative to the neighbors. It further alleviates the location error between its actual and estimated locations. We evaluate our algorithm through extensive simulations under a variety of node densities and anchor placement methods.

• Journal of Korean Society for Geospatial Information Science
• /
• v.16 no.3
• /
• pp.43-49
• /
• 2008

The Real Time Location System (RTLS) is very important in the ubiquitous society for real time tracking of men, high price assets, and logistics products. In this work, we developed an active RF system for RTLS and tested its performance. The RTLS system developed in this work was constructed of three active readers and one active tag. The small size tag developed in this work operated with a coin type battery. To make the tag smaller, we used an internal PCB antenna and a chip antenna. We tested the performance of the tag. To reduce the manufacturing cost of our RF system, we used low price RF transceiver CC2510 chip-set. The CC2510 chip-set provided RSSI(Received Signal Strength Indicator) signal which could be used to determine the distances between an active tag and three active readers.

• Spatial Information Research
• /
• v.17 no.4
• /
• pp.445-454
• /
• 2009

Beyond simple transfer of information through sensor network, this study will provide the insights about the way to embody the real context aware location based service in an ubiquitous computing environment. In this paper, a new formal approach is introduced to derive knowledge about the scope of influence for a point object. A scope of influence is defined as the conceptual area where there is a possibility of the phenomenon or event occurring because of this point object. A point object can be spatially extended by considering this scope of influence in conjunction with the point. These point objects are called Spatially Extended Point (SEP) objects. Compositions of gradual changes of topological relations between a SEP and the environment near the SEP show how to represent the qualitative spatial behaviors of a SEP objects. These qualitative spatial behaviors will be good standards for Location Based Service (LBS) to provide more subdivided and suitable information to the users.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2018.10a
• /
• pp.145-147
• /
• 2018

As mobile devices increase use, users are forced to recognize and navigate their own location and virtual space within a given small display. Unlike trains and buses, this study aims to select a space inside a subway train that is difficult to transfer location information to and suggest an interface to reduce cognitive differences to users. First, observe the actual environment and then derive the empirical factors. Second, by using Metapo which is an act of understanding or experiencing specific targets that are not familiar with familiar objects, the interface is designed according to the UX principle after converting the experience element into metapo. Finally, usability will be assessed through user experience evaluation and problem elicited and supplemented in future studies. This study expects the use of spatial interfaces to be increased and applied as a variety of services by using metaphors through experience elements to help users easily recognize their location within the mobile interface.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.2B
• /
• pp.107-118
• /
• 2009

In this paper, we present design and implementation for identification and location tracking techniques for vehicle information terminals in high-speed mobile environment using IEEE 802.11 wireless LAN technology. RSU be installed at a specific point. RSU recognizes it and then aware identification and location tracking for target vehicle when target vehicle that is equipped with information terminals pass near point. Issue of quick recognition using IEEE 802.11 access management frame, issue of weak wireless LAN security and tracking a range of restrictions be raised and we present solutions. Vehicle information terminal, RSU and a server-side GUI-based management program be implemented based on proposed solution. Implementation system be performed experiment at actual road environment and effectiveness be verified.

• Journal of Digital Contents Society
• /
• v.12 no.3
• /
• pp.361-370
• /
• 2011

Recent popularity of the smartphone market, with the explosive growth of mobile location-based SNS(Social Network Service), is into the mainstream. SNS aims to cooperate and share information with all users, but mobile SNS is still not easy people with disabilities. In addition to using the Web, it has difficulty to provide an appropriate interface to access such as smartphone for people with disabilities. This paper will specify and analyze the context-awareness technology and SNS function, and study a variety of information that students with disabilities such as time, location and activity states including data collection and analysis of the situation by converting the status information. It has provide that students with disabilities to lead comfortable life in school according to the various types of disabilities, and school information and safety services using mobile location-based SNS.

• Journal of the Korean Society for Railway
• /
• v.20 no.5
• /
• pp.703-712
• /
• 2017

The railway system is an interface industry that can be safely operated by organically operating the lines, vehicles, controls, etc. Various data are generated in the operation and maintenance activities of the railway system. These data are utilized in cooperation with safety and maintenance activities in each field, but amount of data is insufficient for data analysis of safety management due to relevant data being produced without any synchronous criteria such as time or space. In particular, reference data such as location and time of failure data for each field are set to different criteria according to the work characteristics in each field. So, it is not easy to analyze data integrally based on location and time. Therefore, mapping of reference data can be required for integrated analysis of data defined in different formats. By selecting data mapping tools and verifying the results of safety relevant data with the same criteria, the purpose of this paper is to enable integrated analysis of railway safety management data occurring in different fields based on location and time.