• 전기전자학회논문지
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• 제22권3호
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• pp.658-663
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• 2018

본 논문에서는 실내 위치 추정시스템에 주로 사용되는 시퀀스 기반 위치추정(Sequence-Based Localization, SBL) 알고리즘의 성능향상을 위한 노드배치 알고리즘에 대해 연구한다. 기존의 노드선택 또는 배치알고리즘은 다수의 타겟이 위치하는 공간의 중심값에 노드들을 위치시켜 성능향상을 이루는 반면, SBL에서는 위치추적 알고리즘 특성상 타겟을 에워싸는 공간에서의 노드배치가 효율적일 수 있음에 주목한다. 이를 실현하기 위해 K-means clustering 알고리즘을 통한 노드배치 가능 공간을 선정하고, 그 선정된 공간상의 효율적 노드위치를 찾기 위해 2분법을 활용하여, 설계 복잡도가 낮은 노드배치 알고리즘을 제시한다. 제안된 노드배치알고리즘은 다양한 모의실험을 통해 무작위 노드배치 알고리즘 대비 뛰어난 위치추정성능을 보여주며, 노드위치를 위한 전역탐색 (full search)과 비교하여, 상당히 낮은 설계복잡도를 유지하면서도 만족할 만한 성능을 보인다.

• 인터넷정보학회논문지
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• 제7권4호
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• pp.45-55
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• 2006

본 논문에서는 현장감 있는 모의훈련을 위해 가상영상이 아닌 지상기반 CCD 카메라영상에 지정된 시나리오대로 가상표적을 전시하는 방법을 제안한다. 이를 위해 고해상도 GeoTIFF(Geonraphic Tag Image File Format) 위성영상과 DTED(Digital Terrain Elevation Data)를 이용하여 현실감 있는 3차원 모델을 생성(운용자용)하고 입력된 CCD 영상(운용자 훈련자용)으로부터 도로를 추출하였다. 그러나 위성영상과 지상기반 센서영상은 관측위치, 분해능, 스케일 등에 많은 차이가 있어 특징기반 정합이 어렵다. 따라서 본 논문에서는 영상 워핑함수인 TPS(Thin-Plate Spline) 보간 함수를 일치하는 두 개의 제어점 집합에 적용하여 3차원 모델에 표시된 이동경로를 따라 CCD 영상에도 표적을 전시하는 이동 동기화 방법을 제안하였다. 실험에서는 대전지역의 위성영상과 CCD 영상을 이용하여 제안한 알고리즘의 유효성을 입증하였다.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.71-79
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• 2006

Epidemiologic studies have showed a close correlation between arsenic exposure and heart disease such as, cardiovascular problem, ischemic heart disease, infarction, atherosclerosis and hypertension in human. It may increase the mortality of high risk group with heart disease. Regarding the mechanism studies of heart failure, blood vessel, vascular smooth muscle cells and endothelial cells have long been focused as the primary targets in arsenic exposure but there are only a few studies on the cardiomyocytes. In this study, the generation of oxidative stress by low dose of arsenic trioxide was investigated in rat cardiomyocytes. By direct measurement of reactive oxygen species and fluorescent microscopic observation using fluorescent dye 2',7'-dichlorofluorescin diacetate, reactive oxygen species were found to be generated without cell death, where cells are treated with 0.1 ppm arsenic for 24 hours. With the induction of reactive oxygen species, GSH level was decreased by the same treatment. However, DNA damage did not seem to be serious by DAPI staining, while high dose of arsenic (2 ppm for 24 hrs) caused fragmentation of DNA. To identify the molecular biomarkers of low-dose arsenic exposure, gene expression was also investigated with whole genome microarray. As results, 9,022 genes were up-regulated including heme oxygenase-l and glutathione S-transrerase, which are well-known biomarkers of oxidative stress. 9,404 genes were down-regulated including endothelial type gp 91-phox gene by the treatment of 0.1 ppm arsenic for 24 hours. This means that biological responses of cardiomyocytes may be altered by ROS induced by low level arsenic without cell death, and this alteration may be detected clearly by molecular biomarkers such as heme oxygenase-1.

• 천문학회보
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• 제41권1호
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• pp.54.3-55
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• 2016

DEEP-South Scheduling and Data reduction System (DS SDS) consists of two separate software subsystems: Headquarters (HQ) at Korea Astronomy and Space Science Institute (KASI), and SDS Data Reduction (DR) at Korea Institute of Science and Technology Information (KISTI). HQ runs the DS Scheduling System (DSS), DS database (DB), and Control and Monitoring (C&M) designed to monitor and manage overall SDS actions. DR hosts the Moving Object Detection Program (MODP), Asteroid Spin Analysis Package (ASAP) and Data Reduction Control & Monitor (DRCM). MODP and ASAP conduct data analysis while DRCM checks if they are working properly. The functions of SDS is three-fold: (1) DSS plans schedules for three KMTNet stations, (2) DR performs data analysis, and (3) C&M checks whether DSS and DR function properly. DSS prepares a list of targets, aids users in deciding observation priority, calculates exposure time, schedules nightly runs, and archives data using Database Management System (DBMS). MODP is designed to discover moving objects on CCD images, while ASAP performs photometry and reconstructs their lightcurves. Based on ASAP lightcurve analysis and/or MODP astrometry, DSS schedules follow-up runs to be conducted with a part of, or three KMTNet telescopes.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.54-54
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• 2008

$Eu^{2+}$, $Nd^{3+}$ co-doped $BaAl_2O_4$ are known as a long afterglow phosphor. We found that $Eu^{2+}$-doped $BaAl_2O_4$ showed ptotoconductivity in the range of UV and visual light. In this study, $BaAl_2O_4$:Eu thin film has been prepared by RF sputtering method and a sensing characteristics to UV and visual light was performed. Only $Eu^{2+}$ and $Nd^{3+}$ co-doped $BaAl_2O_4$ powders and targets for deposition were prepared by a convention solid state method, and the deposition was performed in a reducing $H_2$-Ar mixture gas on Si substrates. The observation of crystalline phase and morphology of the sputtered film were performed using XRD, EDX. The photoluminescence and photocurrent to UV and visual light were measured simultaneously using 300W-Xe solar simulator as a light source. It was confirmed that the photocurrent induced by irradiation of light showed a linear relationship to the light intensity.

• 대한토목학회논문집
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• 제7권4호
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• pp.139-146
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• 1987

지상사진측량(地上寫眞測量)에 의한 3차원변형해석(次元變形測量)은 표정점(標定點)에 대한 3차원좌표(次元變座標)를 계산하고 이들 좌표로부터 변위(變位)를 구하므로써 변형해석(變形測量)을 하게 된다. 지상사진측량(地上寫眞測量)에 의한 변형해석(變形測量)은 3차원좌표(次元變座標) 획득과 변위점검출(變位點檢出) 및 변형량추정(變形量推定)으로 크게 나눌 수 있다. 본(本) 연구(硏究)에서는 처음단계로 번들조정법에 의한 좌표계산에서 지상기준점수(地上基準點數)와 사진수(寫眞數)의 증가에 따른 외부표정요소(外部標定要素)의 분산(分散)-공분산행렬(共分散行列)변화를 분석하였다. 그리고 지상기준점(地上基準點)의 정확도(正確度)를 향상시키기 위한 제약조건을 주기위해 번들조정법에 자유강조정(自由鋼調整)개념을 도입하였다. 이상의 결과분석으로부터 경제성과 시간절약의 측면을 고려할때 지상기준점수(地上基準點數)는 6점(點), 사진수(寫眞數)는 3개가 적합함을 알 수 있다. 또한 번들조정에 자유강조정(自由鋼調整)개념을 적용한 경우 공간거리의 제약조건을 외곽에 분포시키는 것이 바람직함을 알 수 있었다.

• 천문학회보
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• 제37권2호
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• pp.239.1-239.1
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• 2012

This paper presents the results of one of early sciences with Korean VLBI Network (KVN): a large fringe survey of compact radio sources at 43GHz. We established the catalog of correlated flux densities in three ranges of baseline projection lengths of 637 sources from a 43 GHz (Q-band) survey observed with the Korean VLBI Network. Of them, 623 sources have not been observed before at Q-band with VLBI. The goal of this work in the early science phase of the new VLBI array is twofold: to evaluate the performance of the new instrument that operates in a frequency range of 22--129 GHz and to build a list of objects that can be used as targets and as calibrators. We have observed the list of 799 target sources with declinations down to $-40{\circ}$. Among them, 724 were observed before with VLBI at 22 GHz and had correlated flux densities greater than 200 mJy. The overall detection rate is 78%. The detection limit, defined as the minimum flux density for a source to be detected with 90% probability in a single observation, was in a range of 115--180 mJy depending on declination. However, some sources as weak as 70 mJy have been detected. Of 623 detected sources, 33 objects are detected for the first time in VLBI mode. We determined their coordinates with the median formal uncertainty 20 mas. The results of this work set the basis for future efforts to build the complete flux-limited sample of extragalactic sources at frequencies 22 GHz and higher at 3/4 of the celestial sphere.

• 대한원격탐사학회지
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• 제18권2호
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• pp.117-125
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• 2002

연속적으로 상대적으로 짧은 간격으로 관측된 시계열 원격탐사 자료는 관측환경의 악화와 감지 시스템의 기계적 고장과 같은 관측 장애요인에 의해 많은 미관측 및 악성 자료를 가지게 된다. 본 연구는 adaptive 재구축 시스템을 이용하여 동적합성에 의해 미관측 및 악성 자료를 복구하는 문제를 다루고 있다. 제안된 재구축 방법은 관측 대상의 물리적 특성에서의 시간적 변화와 공간적 연속 특성에 근거한 영상처리 기법이며, adaptive 시스템은 관측 값과 지엽적 시간적 경향에 의해 추정된 예측 티의 가중치 합에 의해 합성영상을 생성하는 동적합성을 수행한다. 제안된 동적합성기술의 adaptive 재구축 시스템은 한반도를 관측한 1999년도와 2000년도 2년간의 NOAA AVHRR의 NDVI자료의 재구축에 적용되었다. 실험결과는 재구축된 시리즈는 미관측 및 악성 자료를 포함하고 있는 실제의 관측 영상 시리즈를 위하여 추정된 완전한 자료 값을 갖는 영상 시리즈로 사용될 수 있음을 보여주고 있다. 추가적으로 제안 시스템은 해당 시간에서의 시간적 변화량을 나타내는 gradient 영상을 생성하고, 이러한 영상들의 연속 시리즈에서 관측 대상의 시계열 변화 특성이 관측 자료 값의 영상 시리즈보다 더욱 분명히 나타나고 있다.

• Animal Bioscience
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• 제34권1호
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• pp.143-153
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• 2021

Objective: To explore the molecular mechanisms of fatty liver hemorrhagic syndrome (FLHS) in laying hens, an experiment was conducted to reveal the differences in histopathological observation and gene expression between FLHS group and normal group. Methods: We compared the histopathological difference using hematoxylin and eosin staining and proceeded with RNA sequencing of adipose tissue to search differentially expressed genes and enriched biological processes and pathways. Then we validated the mRNA expression levels by real-time polymerase chain reaction and quantified protein levels in the circulation by enzyme-linked immunosorbent assay. Results: We identified 100 differentially expressed transcripts corresponding to 66 genes (DEGs) were identified between FLHS-affected group and normal group. Seven DEGs were significantly enriched in the immune response process and lipid metabolic process, including phospholipase A2 group V, WAP kunitz and netrin domain containing 2, delta 4-desaturase sphingolipid 2, perilipin 3, interleukin-6 (IL-6), ciliary neurotrophic factor (CNTF), and suppressor of cytokine signaling 3 (SOCS3). And these genes could be the targets of immune response and be involved in metabolic homeostasis during the process of FLHS in laying hens. Based on functional categories of the DEGs, we further proposed a model to explain the etiology and pathogenesis of FLHS. IL-6 and SOCS3 mediate inflammatory responses and the satiety hormone of leptin, induce dysfunction of Jak-STAT signaling pathway, leading to insulin resistance and lipid metabolic disorders. Conversely, CNTF may reduce tissue destruction during inflammatory attacks and confer protection from inflammation-induced insulin resistance in FLHS chickens. Conclusion: These findings highlight the therapeutic implications of targeting the JAK-STAT pathway. Inhibition of IL6 and SOCS3 and facilitation of CNTF could serve as a favorable strategy to enhance insulin action and improve glucose homoeostasis, which are of importance for treating obesity-related disorders for chickens.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제28권2호
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• pp.31-38
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• 2022

Purpose: This study presents the results of the analysis on space utilization of kidney dialysis units in regional public hospitals, which plays a key role in local public medical services. The result aims to achieve safety from infection, allow comfort for the dialysis environment, and stability for medical support. The purpose of this study is to present fundamental data for architectural plans for the kidney dialysis unit, as well as to alleviate potential infectious diseases such as COVID-19. Methods: For research purposes, the investigation and analysis of space utilization were based on architectural floor plans, research papers and literature, related legal systems, and public statistics. Of the main 35 regional public hospitals, in regards to data accessibility, 15 facilities were selected to conduct the survey and analysis for the objective. Results: The space composition by area research results of kidney dialysis units in public hospitals are as follows: Firstly, most targets do not have required rooms in the access and support area, except for the hemodialysis beds in the treatment section. Secondly, the access area requires necessary room and space design that took into consideration of convenience and accessibility for patients. Thirdly, in regards to infection prevention and control, proper circulation and room plan is essential for storage and disposal of contaminated products and linen after use. For the treatment area, the arrangement plan needs to establish a visual connection between the isolation room, the nursing station, and the bed area. Additionally, consideration of circulation in the preparation, treatment, observation, examination, and all other rooms in the facility is required. Lastly, for the support area, the room is designed to consider adequate working and meeting spaces for the medical staff, consultation space for patients or guardians, separate storage and disposal of clean and contaminated items, and the storage of various equipment for dialysis. Implications: In preparation for the increase in chronic kidney failure patients and the spread of infectious diseases, such as COVID-19, the researched data demonstrates the basic guidelines for space composition of kidney dialysis units and the significant role of regional public hospitals.