• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.2B
• /
• pp.119-129
• /
• 2009

According to the advent of the ubiquitous environment, not only a location based service at the outside but also a location based service at the inside was more increased socially. Accordingly, this paper proposes the efficient determination system to locate a object in frequent change of indoor environment. Proposing system in this paper introduce the NLOS identification and mitigation to resolve NLOS problem, using this way that corrects location data as RWA and KF apply to result data can improve accuracy of a object. At last we are going to compare and analyze existing typical triangulation with proposed indoor location determination system to demonstrate algorithm efficiency for proposed indoor location determination system.

• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.317-320
• /
• 2005

The LBS (Location-Based Services) are valuable information services combined the location of moving object with various contents such as map, POI (point of Interest), route and so on. The must general service of LBS is route determination service and its applicable parts are FMS (Fleet Management System), travel advisory system and mobile navigation system. The core function of route determination service is determination of optimal route from source to destination in various environments. The MODB (Moving Object Database) system, core part of LBS composition systems, is able to manage current or past location information of moving object and massive trajectory information stored in MODB is value-added data in CRM, ERP and data mining part. Also this past trajectory information can be helpful to determine optimal route. In this paper, we suggest methods to determine optimal route by querying past trajectory information in MODB system and verify the effectiveness of suggested method.

• Journal of the Korea Safety Management & Science
• /
• v.14 no.1
• /
• pp.209-215
• /
• 2012

This paper deals with the construction of system for correct location determination of fixed tag. We adapted to construct the above method. Also we adapted the several filtering method. This system was constructed through using of several filtering methods to decrease the location determination error and fingerprint method which is composed of training phase and positioning phase. We constructed this system using Labview 2010 and MS-SQL 2000 as database. This system results in less location determination error than least square method, triangulation positioning method, and other fingerprint methods.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.1
• /
• pp.251-256
• /
• 2006

In the work package 'Integrated Positioning' of the research project NAVIO (Pedestrian Navigation Systems in Combined Indoor/Outdoor Environements) we are dealing with the navigation and guidance of visitors of our University. Thereby start points are public transport stops in the surroundings of the Vienna University of Technology and the user of the system should be guided to certain office rooms or persons. For the position determination of the user different location sensors are employed, i.e., for outdoor positioning GPS and dead reckoning sensors such as a digital compass and gyro for heading determination and accelerometers for the determination of the travelled distance as well as a barometric pressure sensor for altitude determination and for indoor areas location determination using WiFi fingerprinting. All sensors and positioning methods are combined and integrated using a Kalman filter approach. Then an optimal estimate of the current location of the user is obtained using the filter. To perform an adequate weighting of the sensors in the stochastic filter model, the sensor characteristics and their performance was investigated in several tests. The tests were performed in different environments either with free satellite visibility or in urban canyons as well as inside of buildings. The tests have shown that it is possible to determine the user's location continuously with the required precision and that the selected sensors provide a good performance and high reliability. Selected tests results and our approach will be presented in the paper.

• Journal of the Korea Safety Management & Science
• /
• v.13 no.1
• /
• pp.99-105
• /
• 2011

Location-Based Service(LBS) is a service that provides a variety of convenience in life using location information that can be obtained by mobile communication network or satellite signal. In order to provide LBS precisely and efficiently, we have to need technologies such as location determination technology, platform technology and server technology first. In this study, we studied on how we can reduce the error on location determination of objects such people and things. Fingerprint location determination method was applied to this study because it can be used at current wireless communication infrastructure and less influenced by a variety of noisy environment than other location determination methods. We used the time of arrival(ToA) method in fingerprint location determination method. In order to confirm the performance of suggested method, we developed location determination test program with LAbVIEW 2010 and performed the test. According to indoor test results, the suggested method reduced the distance error by 24%, 34% and 19% respectively at indoor environment compared with deterministic kWNN and Rice Gaussian fingerprint methods.

• Journal of the Korea Safety Management & Science
• /
• v.16 no.4
• /
• pp.305-311
• /
• 2014

Recently, though it was developed several services using the context-awareness technology of IoT, there exist also obstacles for high quality service. Specifically it is short the study for uncertainty of context-awareness. This study focused on understanding the effect of frequency interference among several environmental factors for location determination to increase precision of location determination. It was found that frequency interference between devices using 2.4Ghz frequency effect on the location determination precision. It was resulted that frequency interference increase the error of location determination precision. Then, we confirmed that it was required the suitable compensation method corresponding to frequency interference.

• Journal of Korea Water Resources Association
• /
• v.46 no.11
• /
• pp.1103-1113
• /
• 2013

In this study, determination methods of the pressure monitoring location in water distribution system were introduced and applied to sample pipe network. The best determination method of the pressure monitoring location was suggested and applied to the real city pipe network. Three kinds of determination methods of pressure monitoring locations are categorized such as the sensitivity analysis according to changing roughness coefficient, pressure contribution analysis, and sensitivity analysis according to changing demand. Further-more, pressure contribution analysis and sensitivity analysis from the results of unsteady analysis were conducted and compared each other. From the results, the most accurate and simplest method was selected in this study. Therefore, the best method can be applied for the pressure management or leakage detection as a determination method of pressure monitoring location in water distribution system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.122-124
• /
• 2010

WPS(Wifi Positioning System) is a location determination technique that utilizes AP information scattered all over the real world. In general, the finger print technique is used for location calculations in WPS. However the finger print technique is a location determination technique that utilizes average values and has problems in the accuracy of the location determination. It also shows low performance of the system due to arithmetic operations. In this paper, the MSS(Max Signal Strength) method is proposed to resolve the existing problems in the finger print technique. The proposed method can reduce the operation time and improve the accuracy of the system under the same conditions. Test environments of the system is presented and the performance of the system is analyzed to verify the methods.

• Journal of Information Technology Services
• /
• v.10 no.4
• /
• pp.243-258
• /
• 2011

With increasing interest in ubiquitous computing technology, an infrastructure for the short-distance wireless communication has been extended socially, bringing spotlight to the security system using the image or location. In case of existing security system, there have been issues such as the occurrences of blind spots, difficulty in recognizing multiple objects and storing of the unspecified objects. In order to solve this issue, zone-based location-estimation search system for the image have been suggested as an alternative based on the real-time location determination technology combined with image. This paper intends to suggest the search service for the image zone-based location-estimation. For this, it proposed the location determination algorism using IEEE 802.15.4/ZigBee's RSSI and for real-time image service, the RTP/RTCP protocol was applied. In order to combine the location and image, at the event of the entry of the specified target, the record of the time for image and the time of occurrence of the event on a global time standard, it has devised a time stamp, applying XML based meta data formation method based on the media's feature data based in connection with the location based data for the events of the object. Using the proposed meta data, the service mode which can search for the image from the point in time when the entry of the specified target was proposed.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.48 no.10
• /
• pp.20-28
• /
• 2011

This paper proposes a reliable high-precision positioning system that converges a satellite navigation system and a vision system in order to resolve position errors and outdoor shaded areas, two disadvantages of a satellite navigation system. In kinematic point positioning, the number of available satellite navigation systems changes in accordance with a moving object's position. For location determination of the object, it should receive location data from at least four satellite navigation systems. However, in urban areas, exact location determination is difficult due to factors like high buildings, obstacles, and reflected waves. In order to deal with the above problem, a vision system was employed. First, determine an exact position value of a specific building in urban areas whose environment is poor for a satellite navigation. Then, identify such building by a vision system and its position error is corrected using such building. A moving object can identify such specific building using a vision system while moving, make location data values, and revise location calculations, thereby resulting in reliable high precision location determination.