• 제목/요약/키워드: reference map

검색결과 450건 처리시간 0.022초

이웃 참조 위치가 없는 경우를 개선한 실내 위치 추정 사전 컷-오프 방식 (An Improved Preliminary Cut-off Indoor Positioning Scheme in Case of No Neighborhood Reference Point)

  • 박병관;김동준;손주영;최종민
    • 한국멀티미디어학회논문지
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    • 제20권1호
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    • pp.74-81
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    • 2017
  • In learning stage of the preliminary Cut-off indoor positioning scheme, RSSI and UUID data received from beacons at each reference point(RP) are stored in fingerprint map. The fingerprint map and real-time beacon information are compared to identify the nearest K reference points through which the user position is estimated. If the number of K is zero, this scheme cannot estimate user position. We have improved the preliminary Cut-off scheme to get the estimated user position even in the case. The improved scheme excludes the beacon of the weakest signal received by user mobile device and identifies neighborhood reference points using the other beacon information. This procedure are performed repetitively until K > 0. The simulation results confirm that the proposed scheme outperforms K-Nearest-Neighbor (KNN), Cluster KNN and the conventional Cut-off scheme in terms of accuracy while the constraints are guaranteed to be satisfied.

휘도맵의 작성을 위한 HDRI 획득에 있어서 EV의 범위 (An EV Range in HDRI Acquisition as a Luminance Map Creation)

  • 홍승대
    • 조명전기설비학회논문지
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    • 제24권10호
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    • pp.5-12
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    • 2010
  • The purpose of this study is to present the EV range in HDRI acquisition process to create luminance map. The proposed method in this study is to capture the scene at EV ${\pm}0$ that is the longest exposure points and reference point in the scene. With this reference point, sets of 25 LDRI test case were taken manually at ${\pm}2$ EV using the aperture-priority manual mode. The 25 HDRIs were created using Adobe Photoshop. The HDRIs were then imported Radiance lighting simulation program to be analyzed into falsecolor. The analysis results of the 25 HDRIs test case are 50[%] of the all tested case have a margin of error of 10[%]. In case of f/5.6, the luminance map generated with HDRI were similar to the spot luminance meter. As a result, the EV range to reduce error of luminance map generated with HDRI is EV $+2{\sim}{\pm}0{\sim}-10$.

2단계 스테레오 정합기법을 이용한 DEM 추정 (DEM Estimation Using Two Stage Stereo Matching Method)

  • 남창우;우동민
    • 대한전기학회논문지:시스템및제어부문D
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    • 제49권12호
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    • pp.659-666
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    • 2000
  • A stereo matching has been an important tool for reconstructing three dimensional terrain. By using stereo matching technique, DEM(Digital Elevaton Map) can be generated by the disparity from a reference image to a target image. Generally disparity map can be evaluated by matching the reference image to the target image and if the role of the reference and the target are interchanged, a different DEM can be obtained. In this paper, we propose a new fusion technique to estimate the optimal DEM by eliminating the false DEM due to occlusion. To detect the false DEM, we utilize two measure of accuracy: self-consistency and cross-correlation score. We test the effectiveness of the proposed methods with a quantitative analysis using simulated images. Experimental result indicate that the proposed methods show 24.4% and 33.1% improvement over either DEM.

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Probabilistic analysis of Italian extreme winds : Reference velocity and return criterion

  • Ballio, G.;Lagomarsino, S.;Piccardo, G.;Solari, G.
    • Wind and Structures
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    • 제2권1호
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    • pp.51-68
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    • 1999
  • Applying and extending some preceding researches, this paper proposes a map of Italian extreme winds assigning the reference velocity, i.e., the wind velocity averaged over 10 minutes, at 10 m height, in a flat open terrain, with 50 years mean return period, depending on the site and the altitude. Furthermore, an objective criterion is formulated by which the actual values of the local wind velocity are given as a function of the reference velocity. The study has been carried out in view of the revision of the Italian Standards dealing with safety and loads and the introduction of the aeolic Italian map into Eurocode 1.

Land Cover Classification Map of Northeast Asia Using GOCI Data

  • Son, Sanghun;Kim, Jinsoo
    • 대한원격탐사학회지
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    • 제35권1호
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    • pp.83-92
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    • 2019
  • Land cover (LC) is an important factor in socioeconomic and environmental studies. According to various studies, a number of LC maps, including global land cover (GLC) datasets, are made using polar orbit satellite data. Due to the insufficiencies of reference datasets in Northeast Asia, several LC maps display discrepancies in that region. In this paper, we performed a feasibility assessment of LC mapping using Geostationary Ocean Color Imager (GOCI) data over Northeast Asia. To produce the LC map, the GOCI normalized difference vegetation index (NDVI) was used as an input dataset and a level-2 LC map of South Korea was used as a reference dataset to evaluate the LC map. In this paper, 7 LC types(urban, croplands, forest, grasslands, wetlands, barren, and water) were defined to reflect Northeast Asian LC. The LC map was produced via principal component analysis (PCA) with K-means clustering, and a sensitivity analysis was performed. The overall accuracy was calculated to be 77.94%. Furthermore, to assess the accuracy of the LC map not only in South Korea but also in Northeast Asia, 6 GLC datasets (IGBP, UMD, GLC2000, GlobCover2009, MCD12Q1, GlobeLand30) were used as comparison datasets. The accuracy scores for the 6 GLC datasets were calculated to be 59.41%, 56.82%, 60.97%, 51.71%, 70.24%, and 72.80%, respectively. Therefore, the first attempt to produce the LC map using geostationary satellite data is considered to be acceptable.

지도 정보를 활용한 저사양 GPS의 위치 정확도 향상 기법 (Low-end GPS Position Accuracy Enhancement Method by using Map Information)

  • 최덕선;강정민;김한솔;박진배
    • 전기학회논문지
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    • 제65권4호
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    • pp.659-665
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    • 2016
  • In this paper, we propose a novel position accuracy enhancement method of a low-end GPS using digital map information. The latest digital map has various kinds of information on geographical features. The proposed method uses position information of lane marks among the geographical features. We define the position information of lane marks as the reference points. The position information of a low-end GPS acquired for a period of time is defined as the source points. In the proposed method, rotation and translation matrices between the reference and the source points are calculated by using an Iterative Closest Point(ICP) algorithm. The source points are transformed by the obtained rotation and translation matrices. Finally, the transformed source points are projected on the reference points. Through these processes, the position accuracy of a low-end GPS is ultimately enhanced. To verify the proposed method, the various real experimental results are presented.

Two-Dimensional Reference Map of Schizosaccharomyces pombe Proteins (Update)

  • Kim, Sun-Kyung;Won, Mi-Sun;Sun, Nam-Kyu;Jang, Jae-Won;Lee, Seung-Hee;Shin, Hee-Young;Song, Kyung-Bin
    • Journal of Microbiology and Biotechnology
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    • 제16권10호
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    • pp.1499-1512
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    • 2006
  • Based on the first 2D reference map of the fission yeast Schizosaccharomyces pombe protein reported previously, we expanded and updated the map using narrower pI ranges. In this paper, 240 protein spots were identified on our reference map. In the pI 4-7 range, 144 spots corresponding to 86 different proteins were identified. In the pI 6-9 range, 43 spots corresponding to 35 different proteins were identified. Fifty-three new spots corresponding to 39 different proteins were further identified in the pI 5-6 range.

재해석자료를 이용한 한반도 해상의 기준풍속 추정 (Estimation of Reference Wind Speeds in Offshore of the Korean Peninsula Using Reanalysis Data Sets)

  • 김현구;김보영;강용혁;하영철
    • 신재생에너지
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    • 제17권4호
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    • pp.1-8
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    • 2021
  • To determine the wind turbine class in the offshore of the Korean Peninsula, the reference wind speed for a 50-y return period at the hub height of a wind turbine was estimated using the reanalysis data sets. The most recent reanalysis data, ERA5, showed the highest correlation coefficient (R) of 0.82 with the wind speed measured by the Southwest offshore meteorological tower. However, most of the reanaysis data sets except CFSR underestimated the annual maximum wind speed. The gust factor of converting the 1 h-average into the 10 min-average wind speed was 1.03, which is the same as the WMO reference, using several meteorological towers and lidar measurements. Because the period, frequency, and path of typhoons invading the Korean Peninsula has been changing owing to the climate effect, significant differences occurred in the estimation of the extreme wind speed. Depending on the past data period and length, the extreme wind speed differed by more than 30% and the extreme wind speed decreased as the data period became longer. Finally, a reference wind speed map around the Korean Peninsula was drawn using the data of the last 10 years at the general hub-height of 100 m above the sea level.

Habitability evaluation considering various input parameters for main control benchboard fire in the main control room

  • Byeongjun Kim ;Jaiho Lee ;Seyoung Kim;Weon Gyu Shin
    • Nuclear Engineering and Technology
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    • 제54권11호
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    • pp.4195-4208
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    • 2022
  • In this study, operator habitability was numerically evaluated in the event of a fire at the main control bench board (MCB) in a reference main control room (MCR). It was investigated if evacuation variables including hot gas layer temperature (HGLT), heat flux (HF), and optical density (OD) at 1.8 m from the MCR floor exceed the reference evacuation criteria provided in NUREG/CR-6850. For a fire model validation, the simulation results of the reference MCR were compared with existing experimental results on the same reference MCR. In the simulation, various input parameters were applied to the MCB panel fire scenario: MCR height, peak heat release rate (HRR) of a panel, number of panels where fire propagation occurs, fire propagation time, door open/close conditions, and mechanical ventilation operation. A specialized-average HRR (SAHRR) concept was newly devised to comprehensively investigate how the various input parameters affect the operator's habitability. Peak values of the evacuation variables normalized by evacuation criteria of NUREG/CR-6850 were well-correlated as the power function of the SAHRR for the various input parameters. In addition, the evacuation time map was newly utilized to investigate how the evacuation time for different SAHRR was affected by changing the various input parameters. In the previous studies, it was found that the OD is the most dominant variable to determine the MCR evacuation time. In this study, however, the evacuation time map showed that the HF is the most dominant factor at the condition of without-mechanical ventilation for the MCR with a partially-open false ceiling, but the OD is the most dominant factor for all the other conditions. Therefore, the method using the SAHRR and the evacuation time map was very useful to effectively and comprehensively evaluate the operator habitability for the various input parameters in the event of MCB fires for the reference MCR.

실내 위치 추정 방식에서 정확도를 향상시키기 위해 컷-오프 핑거프린트 지도를 구성하는 방식 (A Method to Construct a Cut-off Fingerprint Map to Improve Accuracy in Indoor Positioning Scheme)

  • 김동준;손주영
    • 한국멀티미디어학회논문지
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    • 제20권8호
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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.