• Journal of Korea Multimedia Society
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• v.20 no.8
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• pp.1330-1337
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• 2017

In off-line phase of the preliminary Cut-off indoor positioning scheme, which is one of the indoor positioning scheme using the fingerprint, relative ranks of peak RSSIs received from beacons at each reference point are stored in the fingerprint map. In some reference points, signals of multiple beacons may be received. In this case, the relative ranks may be different when constructing fingerprint and when receiving signals in real-time. To solve this problem, we propose a method to utilize only up to five beacons with high ranking when constructing a fingerprint and when receiving signals in real-time and comparing them with stored information of a fingerprint. Experiments were conducted on the estimation probabilities and the average error when using this method. Those are compared with the previous methods. Experimental results show that the estimation probabilities and the average error are improved by removing only the remaining five beacons at each reference point of the fingerprint.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.2
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• pp.97-103
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• 2005

Most car navigation systems(CNS) estimate the vehicle's location using global positioning system(GPS) or dead reckoning(DR) system. However, the estimated location has undesirable errors because of various noise sources such as unpredictable GPS noises. As a result, the measured position is not lying on the road, although the vehicle is known to be restricted on the road network. The purpose of map matching is to locate the vehicle's position on the road network where the vehicle is most likely to be positioned. In this paper, we analyze some general map matching algorithms first. Then, we propose a map matching method using compensation vectors to improve the performance of map matching. The proposed method calculates a compensation vector from the discrepancy between a measured position and an estimated position. The compensation vector and a newly measured position are to be used to determine the next estimation. To show the performance improvement of the map matching using compensation vectors, the real time map matching experiments are performed. The real road experiments demonstrate the effectiveness and applicability of the proposed map matching.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.2
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• pp.129-136
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• 1990

The purpose of the study was to develope brand positioning map for ladies' ready-to-wear, to find out evaluative criteria in perception and preference to brands, and to persent the relationship between consumer's characteristics and brand preference. Subjects were selected for the housewives of middle and high socioeconomic classes living in Seoul area. A questionnaire including items of life style, self image, similarity between brands, preference degree to brands, and demographic variables was developed for the empirical study. The questionnaire was administrated to 137 housewives during fall in 1989. Data were analyzed by cluster analysis and multidimensional scaling method. The study had two research problems. The first research problem was to construct a brand perceptual map for ladies' ready-to-wear brands, selected for the study The perceptual map was constructed on the basis of brand similarity scores by multidimensional scaling method. As a result, brands were grouped into 4 clusters, and evaluative criteria for perceptual map were found to be fashionability (classic- fashionable) and familiarity (familiar-unfamiliar). The second problem was to construct a brand preference map for ladies' ready-to-wear brands, selected for the study. The preference map was constructed on the basis of brand preference scores by multidimensional scaling method. As a result, the brands were grouped into 4 clusters and evaluative critiera for preference map were found to be fashionability (unfashionable-fashionable) and image to age (mature-young directed). Also was shown the relationship among self image, age, socioeconomic class, and brand preference. The multidimensional scaling method was found to be useful as well as valid instrument for brand positioning research and the result can be utilized for establishing strategies for ladies' ready-to-wear brands.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2685-2690
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• 2014

WPS determines position via a two-step process. In the construction phase, a radio map is constituted by collecting radio information signals. Positioning procedure is a step of comparing the radio signal newly acquired with the radio map. If the signals collected and the radio map are different the accuracy decreases. Even though the rate of accuracy is different according to positioning algorithms, accuracy drop is an issue common to all WPS systems. Signal strength fluctuation is caused by the malfunction of the device that receives positioning signals, obstruction and channel interference, etc. In this paper, in order to solve the problem caused by signal strength change, we propose a new radio map construction technique. The proposed method is intended to constitute a strong radio map to changes in the signal strength and updated by collecting the signal strength changes to the radio map. The use of this method is expected to enhance the accuracy of WPS by actively counteracting signal fluctuation.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.334-347
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• 2013

This study aimed to develop positioning strategies through the preparation of a positioning map by introducing brand personality to online shopping malls. Such a study will be able to furnish useful information for establishing differentiated marketing strategies in the online shopping mall market, which has faced fierce competition. For research subjects, the study was aimed at students who were attending S college in the Busan region. The results of an empirical analysis are as follows. The brand personality of online shopping malls were deduced to be the following factors: "competence refinement", "vitality", "intimateness", and "reliability". Then the study prepared a positioning map with these assessment attributes. As a result, there were mutually significant differences among competitive shopping malls in the positioning of consumers. The most differentiated attributes in the perception of the entire group were discovered to be "intimateness" and "vitality", whereas the least differentiated attribute was found to be "reliability". In addition, also in terms of the preference and ideal points for online shopping malls in accordance with brand personality between the entire group and segmented groups, there were mutually significant differences.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.751-756
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• 2002

Since the operation of the first satellite-based navigation services, satellite positioning has played an increasing role in both surveying and navigation, and has become an indispensable tool for precise relative positioning. However, in some situations, e.g. at a low angle of elevation, the use of satellites for navigation is seriously restricted because obstacles like buildings and mountains can block signals. As a mean to resolve this problem, the quasi-zenith satellite system has been proposed as a next-generation satellite navigation system. Quasi-zenith satellite is a system which simultaneously deploys several satellites in a quasi-zenith geostationary orbit so that one of the satellites always stay close to the zenith if viewed from a specific point on the ground of East Asia. Thus, if a position measurement function compatible with GPS is installed in the quasi-zenith and stationary satellites, and these satellites are utilized together with the GPS, four satellites can be accessed simultaneously nearly all day long and a substantial improvement in position measurement, especially in metropolitan areas, can be achieved. The purpose of this paper is to evaluate the effectiveness of quasi-zenith satellite system on positioning accuracy improvement through simulation by using precise orbital information of the satellites and a three-Dimensional digital map. Through this simulation system, it is possible to calculate the number of simultaneously visible satellites and available area of the positioning without the need of actual observation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.239-241
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• 2011

Recently, studies on the indoor positioning system in application of wireless AP have been actively going on. The indoor wireless positioning system can be classified into several types according to the positioning techniques. Among them, the fingerprint technique is a technique that establishes the radio map by collecting MAC information of AP and RSSI (Received Signal Strength Indication) before executing positioning and then determines the position in comparison with the information of AP collected during the course of positioning. In the traditional fingerprint techniques, they control and manage by installing APs that are utilized for positioning. However, in case of specific indoors, the management can be done by installing a small number of APs but, in case of wide outdoors, it's practically impossible to install and manage equipments for positioning. In order to solve such problem, there is an improved fingerprint technique that utilizes the APs that are already scattered around. This technique will allow positioning without additional cost, but even the improved fingerprint positioning technique may incur dropped accuracy as well due to wide fluctuation of the AP information. In this paper, the traditional fingerprint technique and the improved fingerprint technique are explained in comparison, and we will compares difference in performance with the proposed WPS_WS (Wi-Fi Positioning System_Weak Signal) technique.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2006.05a
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• pp.113-127
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• 2006

본 연구에서는 최근에 민간 부문 뿐 아니라 정부부처를 포함한 공공기관에서 확산되고 있는 BSC 성과관리 시스템을 통해 BSC관점에서 출발하여 구성되는 BSC 성과지표이 BSC관점 및 기관이 추구하는 가지고 있는 전략방향과 어떠한 상관관계를 얼마만큼 가지고 있는지를 확인하고, 이를 전략적으로 활용할 수 있는 도구로서 "성과지표 Positioning Map"을 제안하고, 이를 KIST의 BSC 주요성과지표의 내용으로 분석하여 이를 검증해보고자 한다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.395-398
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• 1996

A Global Positioning System(GPS) in an automobile can provide navigational information for identifying the current location of the automobile and helping the drive determine a desirable route to the destination. Usefulness of such a system depends on many design factors. This study examined two critical design factors from a human factors standpoint. The rotation methods and updating schemes of a map were manipulated in a simulated driving environment. Design guidelines are suggested based on the experimental results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.10
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• pp.1917-1922
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• 2017

WPS(Wifi Positioning System) conducts positioning using wireless signals scattered in real world. This process is divided into two stages: Construction Stage that collects information on wireless signals for determining location and constructs a radio map and Positioning Stage that compares the constructed information with the collected information on wireless signals. WPS lowers the accuracy of positioning if changes occur to the collected signals during positioning. PDR have recently been studied. IPS is a system designed to find out the final destination by analyzing pedestrian's no. of gait, travel range, and direction through inertial sensors. If the positioning results of WPS appear in more than two locations, it can be thought as the problem of positioning accuracy. In some cases, problems occur. In this respect, this study analyzes the situations in which the problem as mentioned above occurs and proposes a system to solve this problem through PDR.