• Title/Summary/Keyword: Streak

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The Antimicrobial Activities of some 1,4-Naphthalenediones (IV)

  • Ryu, Chung-Kyu;Kim, Dong-Hyun;Kim, Hee-Joeng;Chung, Sae-Young
    • Archives of Pharmacal Research
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    • v.16 no.4
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    • pp.327-330
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    • 1993
  • A series of 2-chloro and 2-bromo-3-(substituted)-1, 4-naphthalenedione derivatives (1-25) were tested for antifungal and antibacterial activities in vitro against Candida albicans 10231 aand Local, Aspergillus niger KCTC 1231, Tricophyton mentagrophytes KCTC 6085, Fusarium oxysporium KTCC 6501, Bacillus subtilis ATCC 6633, Pseudomonas arruginosa NCTC 10490, Staphylococcus aureus ATCC 6358p, Escherichia coli NIHJ and Acinetobacter baumanii Local. The MiC values were determined by twofold afar diution/streak method. Among thee derivatives, 1, 9, 20, 21, 23 and 25 showed more potent antifungal activities than fluconazole. 20 and 23 completely inhibited the gorwth of fungi, such as Candida albicans, Aspegillus niger, Ticophyton mentagrophytes and fusarium oxysporium, at $3.2\;\mu{g/ml}$. Also some derivatives had the antibacterial activities against Gram-positive bacteria.

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Visualization of Flow inside a Regenerative Turbomachinery

  • Yang, Hyeonmo;Lee, Kyoung-Yong;Choi, Youngseok;Jeong, Kyungseok
    • International Journal of Fluid Machinery and Systems
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    • v.7 no.2
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    • pp.80-85
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    • 2014
  • In this study, we visualized the internal flow of a regenerative turbomachinery using the direct injection tracer method. For visualization, the working fluid was water and the tracer was oil colors (marbling colors). Droplets were injected at the inlet of the machinery and the streak were recorded using a high-speed camera with high-power light sources. While circulating inside the groove, the droplets were translated by the rotational motion of the impeller. When the droplets flow out of the impeller groove, relative to the impeller, they moved more slowly. And the droplets repeatedly reentered into the groove and circulated again. Then the droplets either flowed to the outlet or to the stripper. As a result, this experiment has confirmed the internal circulating flow of a regenerative turbomachinery.

Rapid Quenching Dynamics of F Center Excitation by $OH^-$ Defects in KCI

  • 장두전;김필석
    • Bulletin of the Korean Chemical Society
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    • v.16 no.12
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    • pp.1184-1189
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    • 1995
  • The rapid quenching dynamics of F center excitation by OH- defects in KCl crystals are investigated by monitoring ground state absorption bleach recovery, using a picosecond streak camera absorption spectrometer. F center absorption bleach in OH--doped crystals shows three distinguishable recovery components with the current temporal resolution, designated as slow, medium and fast components. The slow one is due to the normal relaxation process of F* centers as found in OH--free crystals. The others are consequent on energy transfer from electronically excited F centers to OH--vibrational levels. The fast component is a minor energy transfer process and resulting from the relaxation of somewhat distant, not the closest, associated pairs of F* and OH- defects. The energy transfer between widely separated F* and OH- defects opens up a recovery process via the medium component which is assisted by OH- librations, lattice vibrations and OH- dipole reorientations. The quenching behaviors of F* luminescence and photoionization by OH- are explained well by the relaxation process of the medium component.

Study on the Prediction of Turning Point of Typhoon Tracks using COMS Water Vapor Images (천리안 수증기 영상을 이용한 태풍진로의 전향위치 예측 연구)

  • Kim, Jong-Seok;Yoon, Ill-Hee
    • Journal of the Korean earth science society
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    • v.35 no.3
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    • pp.168-179
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    • 2014
  • The purpose of this study focuses on the prediction time and location of turning-point of typhoon tracks using the water vapor images of Communication, Ocean and Meteorological Satellite (COMS) which has a very short observation interval. It targets a more accurate prediction of turning-point of typhoon tracks through the relationship between dry slot and northern/southern oscillations of jet stream. Jet stream moves by the position of jet streak and the ${\upsilon}$-component velocity of geostrophic wind. If the ${\upsilon}$-component of geostrophic wind gets stronger toward south, jet stream develops into a circular jet. In that condition, dry slot in satellite water vapor imagery extends toward south, and typhoon track turns as the distance of curved moisture band (CMB) gets narrowed down. If the interval of CMB is below $15^{\circ}$ of latitude, the typhoon track is turning toward north or northeast within 24 hours. As a result, typhoon track showed that when dry slot position was located less than $32^{\circ}N$, typhoon turned its track at $20-23^{\circ}N$ ($1^{th}$ Kong-Rey 2007 and $17^{th}$ Jelawt at 2012), and when in $35^{\circ}N$ above, it turned at $27^{\circ}N$ ($4^{th}$ Man-yi 2007).

Comparison of Three, Motion-Resistant MR Sequences on Hepatobiliary Phase for Gadoxetic Acid (Gd-EOB-DTPA)-Enhanced MR Imaging of the Liver

  • Kim, Doo Ri;Kim, Bong Soo;Lee, Jeong Sub;Choi, Guk Myung;Kim, Seung Hyoung;Goh, Myeng Ju;Song, Byung-Cheol;Lee, Mu Sook;Lee, Kyung Ryeol;Ko, Su Yeon
    • Investigative Magnetic Resonance Imaging
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    • v.21 no.2
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    • pp.71-81
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    • 2017
  • Purpose: To compare three, motion-resistant, T1-weighted MR sequences on the hepatobiliary phase for gadoxetic acid-enhanced MR imaging of the liver. Materials and Methods: In this retrospective study, 79 patients underwent gadoxetic acid-enhanced, 3T liver MR imaging. Fifty-nine were examined using a standard protocol, and 20 were examined using a motion-resistant protocol. During the hepatocyte-specific phase, three MR sequences were acquired: 1) gradient recalled echo (GRE) with controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA); 2) radial GRE with the interleaved angle-bisection scheme (ILAB); and 3) radial GRE with golden-angle scheme (GA). Two readers independently assessed images with motion artifacts, streaking artifacts, liver-edge sharpness, hepatic vessel clarity, lesion conspicuity, and overall image quality, using a 5-point scale. The images were assessed by measurement of liver signal-to-noise ratio (SNR), and tumor-to-liver contrast-to-noise ratio (CNR). The results were compared, using repeated post-hoc, paired t-tests with Bonferroni correction and the Wilcoxon signed rank test with Bonferroni correction. Results: In the qualitative analysis of cooperative patients, the results for CAIPIRINHA had significantly higher ratings for streak artifacts, liver-edge sharpness, hepatic vessel clarity, and overall image quality as compared to, radial GRE, (P < 0.016). In the imaging of uncooperative patients, higher scores were recorded for ILAB and GA with respect to all of the qualitative assessments, except for streak artifact, compared with CAIPIRINHA (P < 0.016). However, no significant differences were found between ILAB and GA. For quantitative analysis in uncooperative patients, the mean liver SNR and lesion-to-liver CNR with radial GRE were significantly higher than those of CAIPIRINHA (P < 0.016). Conclusion: In uncooperative patients, the use of the radial GRE sequence can improve the image quality compared to GRE imaging with CAIPIRINHA, despite the data acquisition methods used. The GRE imaging with CAIPIRINHA is applicable for patients without breath-holding difficulties.

The Analysis of CT Number Rate of Change of Applying The Iterative Metallic Artifact Reduction Algorithm for CT Reconstruction Image (Iterative Metallic Artifact Reduction 알고리즘 적용 CT 재구성영상의 CT Number 변화율 분석)

  • Kim, Hyeonju;Yoon, Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.7
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    • pp.84-91
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    • 2017
  • This study was performed using Somatom Definition Flash (Siemens, Enlarge, Germany) and GE 64-MDCT (Discovery 750 HD, GE HEALTHCARE, Milwaukee, USA.) using high-density medical materials that (are indispensable to?) computed tomography. We analyzed quantitatively the rate of change of the CT number of the CT reconstruction images by means of the IMAR and MAR algorithms using the phantom images acquired after scanning and previously captured raw data images. As a result, it was shown that the IMAR and MAR algorithms provided if ferent phantom images in the case of all medical high-density materials (p <0.05). The black streak artifacts were analyzed using the MAR and IMAR algorithms to determine if they corresponded to stainless steel materials (p>0.05). Also, it was found that the application of the IMAR algorithm affects the attenuation deviation, because there is a change in the image CT number compared to that before. The results suggest that, in the future, after the implant procedure, it would be useful to observe the surgical site and surrounding tissues during follow-up CT scans.

AUTOMATED STREAK DETECTION FOR HIGH VELOCITY OBJECTS: TEST WITH YSTAR-NEOPAT IMAGES (고속이동천체 검출을 위한 궤적탐지 알고리즘 및 YSTAR-NEOPAT 영상 분석 결과)

  • Kim, Dae-Won;Byun, Yong-Ik;Kim, Su-Yong;Kang, Yong-Woo;Han, Won-Yong;Moon, Hong-Kyu;Yim, Hong-Suh
    • Journal of Astronomy and Space Sciences
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    • v.22 no.4
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    • pp.385-392
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    • 2005
  • We developed an algorithm to efficiently detect streaks in survey images and made a performance test with YSTAR-NEOPAT images obtained by the 0.5m telescope stationed in South Africa. Fast moving objects whose apparent speeds exceed 10 arcsec/min are the main target of our algorithm; these include artificial satellites, space debris, and very fast Near-Earth Objects. Our algorithm, based on the outline shape of elongated sources employs a step of image subtraction in order to reduce the confusion caused by dense distribution of faint stars. It takes less than a second to find and characterize streaks present in normal astronomical images of 2K format. Comparison with visual inspection proves the efficiency and completeness of our automated detection algorithm. When applied to about 7,000 time-series images from YSTAR telescope, nearly 700 incidents of streaks are detected. Fast moving objects are identified by the presence of matching streaks in adjoining frames. Nearly all of confirmed fast moving objects turn out to be artificial satellites or space debris. Majority of streaks are however meteors and cosmic ray hits, whose identity is often difficult to classify.

Analysis of the artifact reduction rate for the types of medical metals in CT with MAR algorithm (CT의 MAR알고리즘 적용 시 의료용 금속 물질별 인공물 감소율 분석)

  • Kim, Hyeon-ju;Yoon, Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.655-662
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    • 2016
  • We investigated on the usefulness of MAR algorithm by making a comparison of the CT value between before and after applying the MAR algorithm in dual energy CT, using the various kinds of medical metals, causing the artifact to lead to the low image quality. As a result, the artifact was reduced in most cases (P<0.05); in particular, the artifact was highly reduced (P<0.05) using high density material, like alloy-stainless (reduced by 78.1%) and platinum, for example GDC coil (reduced by 76.1%). The effect of decreasing the Black hole artifact was outstanding in both the alloy-stainless and alloy-titanium (P<0.05). However, in case of GDC coil-a type platinum, white streak artifact was reduced effectively (P<0.05). Therefore, in case of patients who have medical metals inserted, we think that high-quality image information can be provided by decreasing the artifact caused by high density material through MAR algorithm in dual energy CT.

Development of Sequential Sampling Plan of Bemisia tabaci in Greenhouse Tomatoes (토마토 온실내 담배가루이의 축차표본조사법 개발)

  • SoEun Eom;Taechul Park;Kimoon Son;Jiwon Jeong;Jung-Joon Park
    • Korean journal of applied entomology
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    • v.62 no.4
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    • pp.299-305
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    • 2023
  • Bemisia tabaci is one of polyphagous insect pests that transmits Tomato Yellow Leaf Curl Virus (TYLCV) and Cassava Brown Streak Disease (CBSD). Insecticides are primarily applied to control B. tabaci, but it has limits due to the development of resistance. As a result, a fixed precision sampling plan was developed for its integrated pest management (IPM). The tomato plants were divided into top (more than 130cm from the ground), middle (70 cm to 100 cm above the ground), and bottom (50 cm or less above the ground) strata, before visual sampling of the larvae of B. tabaci. The spatial distribution analysis was conducted using Taylor's power law coefficients with pooled data of top, middle, bottom strata. Fixed precision sampling plan and control decision-making were developed with precision levels and action threshold recommended from published scientific papers. To assess the validation of the developed sampling plans, independent data not used in the analysis were evaluated using the Resampling Validation for Sampling Plan (RVSP) program.

A literatual studies on the furuncle (정瘡에 對한 文獻的 考察)

  • Lee, Jun-Seong;Roh, Seok-Seon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.13 no.2
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    • pp.1-19
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    • 2000
  • 1. The furuncle is nail shaped, whitch tip is sharp and root is deep, very dangerous. It's progress is so rapid and it corresponds to the acute suppurative infection of western medicine. 2. The cause and pathology of the furuncle were divided into three parts, inappropriate care (improper diet and excessive sex), surgical trauma (epidernic infection by domestic animal as like cattle, hoarses, pigs, sheep etc), external evil. 3. The early syndrome of the furuncle is swollen pain, various change of color, fidgetiness, restlessness, aversion to cold, headache, nausea and vomitting etc. Though apply acupuncture, there is no pain and bleeding. There may be streak of blood, curdy of muscles and widen swolling. If it is progressed, its sphere becomes diffuse. This is called as the serious case of furuncle(정독주황). 4. The maim treatment of the furuncle is clear away heat and toxic materials. The method was moxibustion, sticking-plaster, purge blood, oral taking the medicine of detoxication and fire extinguishing etc. 5. The main prescriptionst are omisodokyum(五味消毒飮), hwangyeonheadoktang(黃連解毒湯), ohyangyeongyotang(五香連翹湯), hyeongbangpaedoksan(荊防敗毒散) and so on. The main external prescriptionst are okrhosan(玉露散), cheonchugo(千 膏), guildao(九一丹), palyidan(八二丹), taeyulgo(太乙膏), hongyugo(紅油膏) and so on.

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