• 한국항행학회논문지
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• 제19권6호
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• pp.558-563
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• 2015

최근 실내 위치측위 기술을 이용하여 다양한 서비스가 이루어지고 있다. 실내 위치측위 방식에는 대표적으로 fingerprinting 방식과 삼변측량 방식이 있으나 활용의 제한성 및 위치추정 오차 등의 문제점이 있다. 이러한 문제점을 해결하기 위해 기존의 측위 방식인 AOA, TOA, TDOA 등의 측위 기술을 응용한 연구가 진행되고 있다. 본 논문에서는 실내 환경에서 RSSI 차이를 이용한 AOA 기반 위치 추정 알고리즘에 대해 연구한다. 4개의 안테나를 가지는 하나의 AP를 가정하여 연구를 진행하며, RSSI를 기반으로 도래각을 추정 후 AOA 알고리즘에 적용한다. RSSI의 보정을 위해 재귀식 평균 필터를 이용하며, 도래각 추정을 위해 보정된 RSSI와 피타고라스 정리를 이용한다. 실험 결과 좁은 간격으로 배치된 4개의 무지향성 안테나의 방사 패턴으로 인하여 18%의 오차율을 보였으며, 지향성 안테나를 이용할 경우 실내 환경에서 AOA 알고리즘을 활용할 수 있을 것으로 판단된다.

• 융합신호처리학회논문지
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• 제22권3호
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• pp.134-140
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• 2021

본 연구는 에너지 하베스팅 기반 저전력 GPS와 IMU를 활용한 개인 위치를 식별할 수 있는 웨어러블 장치 개발에 관한 것이다. 개발된 개인 위치식별 장치는 압전소자를 이용한 에너지 하베스팅 기술을 적용하였고, GPS 및 IMU를 사용하여 정밀한 개인위치 데이터를 획득할 수 있도록 하였다. 실험 결과, GPS 및 IMU 데이터가 정상적으로 수신함을 확인하였다. 개인위치 식별장치는 재난 발생지역 등에서의 개인위치를 파악하여 안전사고에 대응하고, 시간, 장소 및 환경에 구애받지 않고 사용자가 손쉽게 사용할 수 있을 것이며, 레저나 헬스케어 등 다양한 방면에서 사용이 가능할 것으로 기대된다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.229-232
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• 2005

Many kinds of communication systems will be co-existed in the next generation communication environment. Location management will be one of the most important strategies in the future communication network. Whether the user gets the service in any kind of communication system, it is required to know the location of the user properly and manages this location information efficiently. In this paper, mobile IP and WCDMA systems are considered as next generation communication systems. We improve the performance of communication in heterogeneous networks adjusting the conventional region-based location management strategy in homogeneous network. This strategy can be adjusted dynamically to the communication system on the basis of packet-to-mobility ratio (PMR) in mobile IP system or call-to-mobility ratio (CMR) in WCDMA system, lots of different system parameters, and movement pattern of the user. This can be also based on the performance analysis with considering signaling cost and database access cost.

• 한국항해항만학회지
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• 제43권5호
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• pp.281-288
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• 2019

In this paper, we implemented a mobile application of location-based augmented reality that combines self-sensing technology and various safety information using technological advancements of the smartphone. Vessel navigation is a suitable area for augmented reality because it requires accurate knowledge of the distance and location of destinations, danger zones, AtoN, and adjacent vessels. Current smartphone applications only provide 2D images and location information. Such applications do not include information about the surrounding environment, and as a result, they can only function using their own sensing information and surrounding information into a location-based augmented reality. If you provide a variety of sensor information embedded in the smartphone to 'BadaGO', the implemented application through this study, 'BadaGO' can provide safe navigation information to the user device in real time with a variety of its own formed information. The user has a high practicality and applicability of a small ship that is supplied with safe navigation information in a changing marine environment only by providing information through the application on the smartphone.

• 한국항행학회논문지
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• 제12권1호
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• pp.15-21
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• 2008

본 논문에서는 관리대상자의 위치 및 기타 관련 정보를 위치관리시스템(LMS : Location Management System)에서 항시 감시 및 관리할 수 있는 GPS 기반 위치 인식 단말시스템 및 위치관리시스템을 구현하였다. 구현한 시스템은 PID(Personal Identification Device)의 정보를 전송하기 위한 모듈과 GPS 기반의 위치정보 수집 모듈로 구성된 위치 인식 단말장치 (Mobile HTE : Mobile Home Terminal Equipment)와 Mobile HTE에서 수신된 정보를 인터넷 망을 통하여 위치관리시스템에 전송할 수 있는 단말장치 (HTE : Home Terminal Equipment)를 구현하여 관리대상자의 위치를 관리할 수 있는 위치관리시스템을 설계 하였다.

• 한국화재소방학회논문지
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• 제16권4호
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• pp.33-43
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• 2002

선박기관실과 유사한 공간내로 $CO_2$소화제를 분사했을 때 화재화염이 공기유동 및 $CO_2$소화제전달 특성에 미치는 영향을 분석하기 위하여 수치해석을 수행하였다. 노즐 위치에 따라 유동장과 $CO_2$농도장을 계산하였다. 한 경우를 제외한 모든 경우에서 시계방향과 반시계방향 재순환 유동이 노즐 좌, 우측영역에 형성되었으며, 이러한 재순환 유동이 질량전달과 $CO_2$소화제 확산경로에 큰 영향을 미치는 것을 알 수 있었다. 화재화염이 위치한 1층 영역에서는 $CO_2$소화제 확산경로가 재순환 유동 확장경로와 일치하였다.

• 대한가정학회지
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• 제30권3호
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• pp.131-140
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• 1992

The purpose of this study was to investigate the heating regulation systems and the thermal environment of the Co-Generation apartment house in winter. Personal self-administration and interview method were used in the survey of this study. The respondents were 352 housewives who resided in Mokdong apartement using Co-Generation heating systems. Data was analyzed using SPSS PC+ computer package. The results of this study were summarised as follow; The typical patterns of heating regulation systems were intermittent and partial heating in the living room and bedroom exclusive of kitchen area. The present condition of the thermal environment were relatively warm in winter and Heatng regulation systems were influenced by type of location. Determinants of the thermal sensation and thermal comfort were the type of location of apartment as a architectural factor, clo as a personal factor.

• 한국멀티미디어학회논문지
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• 제22권9호
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• pp.1122-1131
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• 2019

This paper covers research on terrain construction for unmanned aerial vehicle simulators using spatial information that was distributed by public institutions. Aerial photography, DEM, vector maps and 3D model data were used in order to create a realistic terrain simulator. A data converting method was suggested while researching, so it was generated to automatically arrange and build city models (vWorld provided) and classification methods so that realistic images could be generated by 3D objects. For example: rivers, forests, roads, fields and so on, were arranged by aerial photographs, vector map (land cover map) and terrain construction based on the tile map used by DEM. In order to verify the terrain data of unmanned aircraft simulators produced by the proposed method, the location accuracy was verified by mounting onto Unreal Engine and checked location accuracy.

• 보험의학회지
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• 제2권1호
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• pp.260-266
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• 1985

Pregancy is a part of women's life and is common process experienced by most women. On the other hand, a few cannot be pregnant. There are many reasons of infertility and myoma uteri of pelvic mass is a rare reason of infertility. Complication of pregnancy accompanied with myoma uteri is largely affected by the size or location of mass and the incidence by myoma uteri in pregnancy rarely happened, but mass with long pedunculus causes torsion as uterus is getting bigger. In labor myoma uteri causes the abnormal condition of fetal presentation and results in the abnormal childbirth. In case of myoma uteri, maternal mortality is low and there by medical hazards also decrease, but as the life insurance medical is the extensive prediction science, we believe that the prediction of perinatal or the condition of afterbirth by knowing the location, size of myoma uteri contributes to the medical examination. We experienced one case of Elderly primigravida with myoma uteri in Med Dept of Dae Han Kyouk life Insurance Co. Ltd. which the insured with medical examination believe herself as menopause. So we report the observations with studies.

• Computers and Concrete
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• 제19권3호
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• pp.257-262
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• 2017

The aim of this study is to investigate the pH threshold value for the corrosion of steel reinforcement in concrete. A method was designed to attain the pH value of the pore solution on the location of the steel in concrete. Then the pH values of the pore solution on the location of steel in concrete were changed by exposing the samples to the environment (CO25%, RH 40%) to accelerate carbonation with different periods. Based on this, the pH threshold value for the corrosion of steel reinforcement had been examined by the methods of half-cell potential and electrochemical impedance spectra (EIS). The results have indicated that the pH threshold value for the initial corrosion of steel reinforcement in concrete was 11.21. However, in the carbonated concrete, agreement among whether steel corrosion was initiatory determined by the detection methods mentioned above could be found.