• Journal of Positioning, Navigation, and Timing
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• 제9권2호
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• pp.139-147
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• 2020

In this paper, design measure were proposed for the construction of terminal systems for airborne platforms, which are key element in the Joint Tactical Data Link System (JTDLS) complete system. The Korean perfect tactical data link (JTDLS) is a communication system to establish an independent tactical data link network and needs to develop a MIDS-LVT (Link-16) communication terminal for datalink. Once a Ground/Navy JTDLS terminal system is established around airborne platform, it will be possible to break away from reliance on NATO-based tactical data link joint operations and establish independent Korean surveillance reconnaissance real-time data sharing and tactical data link operations concepts. in this paper, the essential development elements of airborne platform mounting and operable JTDLS terminals are presented, and the concept of system design is proposed to embody them. Further, improved system performance was analyzed by applying the concepts of complex relative navigation system and Advanced TDMA protocol for the deployment of airborne tactical datalink networks.

• 전자공학회논문지B
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• 제33B권5호
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• pp.109-178
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• 1996

For each reference station and user, the proposed DGPS system is implemented by a GPS module and a modem. The reference station makes plans of the receiving schedule from the satellite sets at each period and then provides the correction data for various satellite sets in a period. Users can utilize the correction data continuously and efficiently through the recursive least squares lattice filters. Furthermore, after taking DGPS techniques, we can improve the positioning accuracy using a kalman filter by decreasing anti-common errors between a reference station and a user. Experimental results show the positioning accuracy of better than 5 meters in almost real time.

• Journal of the Korean Data and Information Science Society
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• 제17권3호
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• pp.677-685
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• 2006

During the previous few years, local universities have experienced a rapid decrease in registration of new student for admission because of the problem of excessive concentration to Seoul metropolitan area and decrease in the number of population under school ages. Even though they are tring to survive from the difficulties by developing new strategies to increase the number of new students, it has no meaning if there is no standpoint of marketing. So, this study suggests that introduction of demander focused marketing concept actively is needed breaking the general and conservative method when the university devise entrance examination strategy. Also, using of positioning map is suggested and the examples are showed as finding differentiation factors with competitive university.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1286-1291
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• 2017

In this paper, we propose an indoor positioning system that makes use of the attenuation model for IEEE 802.11 Channel State Information (CSI) in order to determine its distance from an Access Point (AP) at a fixed position. With the use of CSI, we can mitigate the problems present in the use of Received Signal Strength Indicator (RSSI) data and increase the accuracy of the estimated mobile device's location. For the experiments we performed, we made use of the Intel 5300 Series Network Interface Card (NIC) in order to receive the channel frequency response. The Intel 5300 NIC differs from its counterparts in that it can obtain not only the RSSI but also the CSI between an access point and a mobile device. We can obtain the signal strengths and phases from subcarriers of a system which in turn means making use of this data in the estimation of a mobile device's position.

• 수산해양기술연구
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• 제29권2호
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• pp.109-116
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• 1993

Underwater acoustic positioning systems have been extensively used not only in surface position fixing but also in underwater position fixing. Recently, these systems have been applied in the field of installation and underwater inspection of offshore platforms etc. But in these systems are included the fixing errors as results of a signal with additive noise and irregular motion of vessel by ocean waves. To improve the accuracy of the position fixing a Kalman filter is applied to the supershort baseline (SSBL) acoustic positioning system with beacon mode in noise conditions. The position data obtained by the Kalman filter is compared with raw position data and it is confirmed in the simulation that the former is more accurate than the latter. And an indicator monitoring the filtering effect is described while ship's moving.

• 인터넷정보학회논문지
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• 제10권1호
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• pp.159-173
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• 2009

일반적으로 무선 센서 네트워크는 다수의 노드들을 무작위로 배포하여 데이터를 수집하기 때문에 각 노드로부터 수집되는 데이터뿐만 아니라 계측하는 노드의 위치 또한 매우 중요하다. 무선 센서 네트워크를 구성하는 노드들은 저비용, 저성능의 장치들로 구성되어 있어 위치 측정을 위한 전용 장치를 노드에 추가하는 것은 매우 어렵다. 그러므로 무선센서 네트워크에서 저비용으로 노드의 위치를 정확히 측정하는 것은 매우 중요한 기술이다. 본 연구에서는 위치 측정의 정확성을 높이고, 다수의 센서에 대해서도 정해진 시간 내에 위치를 결정할 수 있는 확장 가능한 상호 협력 위치 측정 시스템을 제안한다. 그리고 시뮬레이션을 통하여 성능, 정확성, 확장성이 우수함을 보였다.

• 한국조리학회지
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• 제12권3호
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• pp.219-236
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• 2006

The purpose of this study is to examine the elements that satisfy customers in order for restaurants to survive in competition, and to examine effective positioning strategies. Since the designation of Haeundae in Busan as a Special Tourism Zone, diverse food service markets have been established and various marketing activities are anticipated accordingly. The results of this study can be summarized as follows: First, after the examination of the competitive relationships among restaurants, based on the image similarity data, it was found that Bennigan's, Outback Steakhouse, and T.G.I. Friday's are in close proximity with one another. Hence the fierce competition between them. Secondly, as a result of PC-MDS PROFIT analysis, a positioning map was drawn with image similarity measurement of the restaurants and scores 9 evaluation categories for each brand name as follows: food taste, food price, service, access convenience, hygienic condition and cleaning, atmosphere, various events, circumferential environment, and public image. Thirdly, as a result of MDPREFMAP analysis based on the customer preference, data from the restaurant brand names, an ideal location of a restaurant preferred by customers and the position of restaurant brand names were indicated at the same time.

• 대한공간정보학회지
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• 제13권1호
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• pp.37-43
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• 2005

GPS 기술의 빠른 발전에 힘입어 정밀 측위 분야에도 GPS의 활용은 증가하고 있다. GPS로부터 정밀한 좌표를 획득하기 위해서 GPS 신호에서 모호 정수값을 정확하게 결정하는 것이 중요하다. 이를 위해 기존에는 다중시점(multi-epoch) 데이터를 사용한 방법이 일반적이었으나 최근에 단일시점(single-epoch) 데이터를 이용한 방법이 개발되었다. 이에 본 연구는 각각의 방법이 구현된 세 가지 소프트웨어를 활용하여 GPS 기선해석과 관련된 다양한 실험을 수행하여 결과를 분석하였다. 이를 통해 실시간 정밀 측위에 대한 이용 가능성을 검증하였다.

• 한국위성정보통신학회논문지
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• 제5권2호
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• pp.69-74
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• 2010

본 논문에서는 LED 조명 기반의 실내 측위 시스템을 제안하였다. LED가 빛을 방출하며 고속의 switching이 가능하다는 반도체 조명이라는 특징을 이용하여 각각의 LED 조명에 고유의 8 비트 ID를 부여 후, 이를 방출되는 조명 빛에 변조하여 보내주었다. 수신기는 16 개의 LED 조명으로부터 조합된 정보를 수신하게 되고, 수신된 정보와 각각의 ID 정보 간의 correlation coefficient를 이용하여 $4\;m\;{\times}\;4\;m\;{\times}\;2\;m$의 공간에서 100 cm 및 50 cm resolution을 가지는 위치인식 시스템을 시뮬레이션을 통해 구현하여 보았다. 제안된 측위 시스템은 간단한 알고리즘을 사용하였고, LED 조명 인프라를 사용하여 구축함으로써 설치비용 절감이 가능할 것이라 기대된다.

• 한국융합학회논문지
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• 제9권11호
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• pp.1-7
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• 2018

최근 들어, 실내 공간에서의 활동 영역이 넓어지면서 실내 공간에서의 사용자 위치 측위, 추적, 공간 패턴 분석, 환경 분석 등 다양한 형태의 공간 활용 서비스 기술이 개발, 적용되고 있다. 이러한 실내 공간에서의 서비스 기술을 위해 BLE 기반의 Beacon이 대표적으로 사용되고 있다. 따라서, 본 논문에서는 비콘을 기반으로 실내 위치 측정에 대한 신호를 수집, 분석하여 비콘을 이용한 실내 위치 측정의 효율성을 분석하기 위한 모듈을 설계하였다. 실험 결과, 근거리에서 측정된 데이터의 정확도가 높으며, 실내 공간에서 장애물이 없을수록 위치 데이터가 보다 정확하게 추출되는 것으로 분석되었다.