• 제목/요약/키워드: ARI

검색결과 215건 처리시간 0.035초

드론 초분광 영상과 다중 식생지수를 활용한 태화강 유역 식생변화 분석 (Analysis of vegetation change in Taehwa River basin using drone hyperspectral image and multiple vegetation indices)

  • 김용석
    • 한국환경복원기술학회지
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    • 제24권1호
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    • pp.97-110
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    • 2021
  • Vegetation index information is an important figure that is used in many fields such as landscape architecture, urban planning, and environment. Vegetation may vary slightly in vegetation vitality depending on photosynthesis and chlorophyll content. In this study, a range of vegetation worth preserving in the Taehwa River water system was determined, and hyperspectral images of drones were acquired (August, October), and the results were presented through DVI(Normalized Defference Vegetation Index), EVI(Enhanced Vegetation Index), PRI(Photochemical Reflectance Index), ARI (Anthocyanin Reflectance Index) index analysis. In addition, field spectral data and VRS-GPS(Virtual Reference System-GPS) surveys were performed to ensure the quality and location accuracy of the spectral band. As a result of the analysis, NDVI and EVI showed low vegetation vitality in October, -0.165 and -0.085, respectively, and PRI and ARI increased to 0.011 and 7.588 in October, respectively. For general vegetation vitality, it was suggested that NDVI and EVI analysis were effectively performed, and PRI and ARI were thought to be effective in analyzing detailed characteristics of plants by spectral band. It is expected that it can be widely used for park design and landscape information modeling by using drone image information construction and vegetation information.

Patient's Factors Correlated with Prostate Volume Recovery after 5 Alpha Reductase Inhibitor Discontinuation

  • Choi, Kwibok;Kim, Byounghoon;Cho, In-Chang;Min, Seung Ki
    • Urogenital Tract Infection
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    • 제13권3호
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    • pp.79-83
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    • 2018
  • Purpose: The 5 alpha reductase inhibitor (5ARI) reduces the size of the prostate and alleviates lower urinary tract symptoms. After stopping 5ARI, the prostate quickly recovers to its pre-medication size. The purpose of this study was to investigate the factors affecting the restoration of prostate size after 5ARI discontinuation. Materials and Methods: Between March 2009 and May 2017, patients who visited an outpatient clinic and were diagnosed with benign prostatic hyperplasia were selected and start 5ARI medication. After 6 months of medication, the patients stopped medication for 1 year. Meanwhile, we measured the prostate volumes of patients 3 times (before and after medication, after discontinuation) and divide the patients into 3 groups (maintained, intermediate, and restored) with recovered prostate volume ratio. After classification, we investigated the relationship between the variable factors (age, serum prostate-specific antigen, initial volume, reduced volume after medication) between groups. Results: Among the 147 selected patients, the mean age and plasma PSA level were $61.6{\pm}7.9$ and $0.8{\pm}0.6$, respectively. The mean initial prostate volume was $32.3{\pm}4.2ml$, which reduced to $23.2{\pm}3.2ml$ after medication. After one year of discontinuation, the mean volume was $31.4{\pm}6.4ml$, with restoration to 101.5% of the reduced size. We noticed a tendency that patients with faster prostate volume recovery were generally older than those with slower recovery; however, this was not statistically significant. Other factors showed no relationship with prostate recovery. Conclusions: When using 5ARI in elderly patients, continuous treatment seems better than intermittent treatment. If discontinuation is needed, short term follow-up is recommended.

How Market Orientation Can Sustain Islamic Microfinance Institutions?

  • Kazemian, Soheil;Rahman, Rashidah Abd;Ibrahim, Zuraeda;Kamaruddin, Badrul Hisham;Mohd, Rohani
    • 동아시아경상학회지
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    • 제2권3호
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    • pp.23-32
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    • 2014
  • Even though Islamic microfinance has flourished in the last two decades, still it faces some problems related to its sustainability and outreach. Market orientation has generally developed some strategies for organizations aiming to retain the current customers and attract new ones. In addition, organizations, which are addressed as Islamic, should be Shariah-compliant in all aspects. This paper introduces the market orientation concept which is adapted to Shariah rules and recommends a solution for sustainability problems of Islamic microfinance institutions. Current study tries to provide some intangible instances and evidences to introduce and use Islamic market orientation concept for Islamic microfinance institutions, in particular.

직접 부착법과 간접 부착법이 열순환 후 부착강도와 미세누출에 미치는 영향에 대한 연구 (Effects of direct and indirect bonding techniques on bond strength and microleakage after thermocycling)

  • Ozturk, Firat;Babacan, Hasan;Nalcaci, Ruhi;Kustarci, Alper
    • 대한치과교정학회지
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    • 제39권6호
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    • pp.393-401
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    • 2009
  • 본 연구는 직접 또는 간접 부착법으로 부착한 교정용 브라켓을 열순환 처리 후에 전단 결합 강도(shear bond strength, SBS)와 치아-접착제-브라켓 복합체의 미세 누출을 비교하기 위하여 시행하였다. 50개의 치아우식증이 없는 사람 소구치를 구하여 동등한 2개의 군으로 나누었다. 직접 부착군에서는 광중합 접착제 및 primer (Transbond XT)를 사용하였고 간접 부착군에서는 광중합 접착제와(Transbond XT) 화학중합 primer (Sondhi Rapid Set)를 사용하였다. 중합 후에 치아는 24시간 동안 증류수에 보관하였고 이후 500회 열순환 처리를 하였다. 미세누출의 평가를 위해 각 군에서 10개의 치아에 nail varnish로 추가 봉연을 실시하고 0.5% basic fuchsin에 24시간 동안 염색한 후 입체현미경으로 검경하였다. 만능시험기를 이용하여 각 군의 치아 15개로 SBS를 계측하였고 adhesive remnant index (ARI)를 평가하였다. 결과 자료는 Mann-Whitney U test, Chi-square test, Fisher's exact test로 통계 분석하였다. 직접 부착군과 간접 부착군 사이에 SBS 및 미세누출의 통계적으로 유의한 차이는 보이지 않았으며 간접 부착군에서 통계적으로 유의하게 ARI 점수가 낮았다. 브라켓의 탈락은 법랑질-레진 계면에서 발생하였다. 이상의 결과로 보아 부착법의 차이는 미세누출의 양과 SBS에 유의한 영향을 미치지 않는다.

EXOSAT X-RAY LIGHT CURVES OF SS ARI

  • Kim, Yong-Gi
    • Journal of Astronomy and Space Sciences
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    • 제15권1호
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    • pp.65-68
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    • 1998
  • We construct the X-ray light curves of the W UMa type contact binary SS Arietis(HD12929) from the EXOSAT data in HEASARC data archive. The phase dependent X-ray light curves obtained by using the ephimeris of Kaluzny & Pojmanski of SS Ari is modulated on the orbital phase as in the case of other W UMa type binaries. Although a detailed analysis of these data is impossible because of the very low X-ray light curves in the context of the radiation in the corona region of W UMa type stars.

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경량화된 MAC을 이용한 강력한 Yoking-Proof 프로토콜 (Strong Yoking-Proof Protocol using Light-Weighted MAC)

  • 조창현;이재식;김재우;전문석
    • 정보보호학회논문지
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    • 제19권6호
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    • pp.83-92
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    • 2009
  • RFID 시스템을 이용하여 다수의 태그를 동시에 인증하기 위한 방법으로 Ari Juels는 Yoking-Proof 프로토콜을 제안하였다. 일반적인 Yoking-Proof 방법은 MAC(Message Authentication Code)을 이용하여 인증을 하기 때문에, 저가형 태그에 적용하기가 어렵다. MD5와 같은 일반적인 해쉬함수도 저가형 태그에 구현하는 것은 쉽지 않기 때문이다. 따라서 Ari Juels는 한번만 인증가능한 경량화된 Yoking-Proof 방법도 함께 제안하고 있다. 하지만 제안된 방법에서 사용된 경량화된 MAC인 Minimalist MAC은 그 특성상 한번만 사용가능하고, 또한 제안된 구조는 재생공격에 취약한 구조를 가지고 있다. 따라서 본 논문에서는 Lamport가 제안한 디지털 서명기법을 이용한 경량화된 MAC을 이용하여, 기존에 제안된 논문보다 재생공격에 강하고 다수의 키 값을 저장할 수 있는 형태의 태그를 이용한 Yoking-Proof 프로토콜을 제안한다.

시변 불확실성을 가지는 선형 시스템을 위한 반복 제어 시스템의 설계 (Design of Repetitive Control System for Linear Systems with Time-Varying Uncertainties)

  • 정명진;도태용
    • 제어로봇시스템학회논문지
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    • 제11권1호
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    • pp.13-18
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    • 2005
  • This paper considers a design problem of the repetitive control system for linear systems with time-varying norm bounded uncertainties. Using the Lyapunov functional for time-delay systems, a sufficient condition ensuring robust stability of the repetitive control system is derived in terms of an algebraic Riccati inequality (ARI) or a linear matrix inequality (LMI). Based on the derived condition, we show that the repetitive controller design problem can be reformulated as an optimization problem with an LMI constraint on the free parameter.

Optimal Periodic PM Schedules Under $ARI_1$ Model with Different Pattern of Wear-Out Speed

  • Lim Jae-Hak
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2005년도 학술발표대회 논문집
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    • pp.121-129
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    • 2005
  • In this paper, we consider a periodic preventive maintenance(PM) policy in which each PM reduces the hazard rate of amount proportional to the failure intensity, which increases since the last PM and slows down the wear-out speed to that of new one. And the proportion of reduction in hazard rate decreases with the number of PMs. Our model is similar to $ARI_1$ proposed by Doyen and Gaudoin(2004) in the sense of reduction of hazard rate. Our model has totally different wear-out pattern of hazard rate after PM's, however, and the proportion of reduction depends on the number of PM's. Assuming that the system undergoes only minimal repairs at failures between PM's, the expected cost rate per unit time is obtained. The optimal number N of PM and the optimal period x, which minimize the expected cost rate per unit time are discussed. Explicit solutions for the optimal periodic PM are given for the Weibull distribution case.

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TT Ari: Recent negative superhumps and QPO'w

  • Kim Y.;Yoon J.N.;Cha S.M.;Andronov I.L.;Chinaiova L.L.
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 2006년도 한국우주과학회보 제15권1호
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    • pp.72-72
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    • 2006
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