• Title/Summary/Keyword: Spectral studies

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Studies on Essential Oils of Plants of Angelica Genus in Korea (IV) -Essential Oils of Angelicae koreanae Radix- (Angelica속 생약의 정유성분에 관한 연구(IV) -강활의 정유성분-)

  • Chi, Hyung-Joon;Kim, Hyun-Soo
    • Korean Journal of Pharmacognosy
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    • v.24 no.2
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    • pp.111-115
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    • 1993
  • Essential oil of the root of Angelica koreana Max. (Umbelliferae) was investigated. Essential oil was obtained from the dried roots by steam distillation and fractionated by column chromatography. Each isolate or fraction was identified by GC, GC-MS and spectral analysis. It was found to contain nine monoterpenes such as ${\alpha}-pinene$(7.0%), camphene, ${\beta}-pinene$, myrcene, ${\alpha}-phellandrene$, ${\Delta}-3-carene$, p-cymene, limonene(2.8%), terpinolene and also found to contain m-cresol(11.6%), citronellol, citral b, methylcinnamate, eudesmol and osthol. 2-Hydroxy-5-methylacetophenone and twelve compounds were tentatively identified.

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Dyeing Performance of Disperse Dyes Based on 2-aminothiazole for Cellulose Triacetate and Nylon Fibers

  • Maradiya, Hari-Raghav;Patel, Vithal-Soma
    • Fibers and Polymers
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    • v.3 no.1
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    • pp.43-48
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    • 2002
  • A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using various N,N-dialkvlaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers. These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing, perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good.

An Analysis of the English l Sound Produced by Korean Students

  • Yang, Byung-Gon
    • Speech Sciences
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    • v.15 no.1
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    • pp.53-62
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    • 2008
  • The purpose of this study was to examine the English l sound in an English short story produced by 16 Korean students in order to determine various allophones of the sound using acoustic visual displays and perceptual judgments. The subjects read the story in a quiet office at normal speed. Each word included the lateral sound in onset or coda positions and before a vowel of the following word. Results showed as follows: Firstly, there was a durational difference between the two major groups. Also the majority of the subjects produced the clear l regardless of the contexts. Some students produced the sound as the Korean flap or the English glide [r]. A few missing cases were also seen. The dark l was mostly produced by the subjects of English majors in coda position with a few cases before a vowel in a phrase. Visual displays using the computer analysis were very helpful in distinguishing lateral variants but sometimes perceptual process would be necessary to judge them in fast and weak production of the target word. Further studies would be desirable to test the discrepancies between the acoustical and perceptual decisions.

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AKARI INFRARED CAMERA SURVEY OF THE LARGE MAGELLANIC CLOUD

  • Shimonishi, T.;Kato, D.;Ita, Y.;Onaka, T.;AKARI/IRC LMC team
    • Publications of The Korean Astronomical Society
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    • v.32 no.1
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    • pp.83-85
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    • 2017
  • We conducted an unbiased near- to mid-infrared imaging and spectroscopic survey of the Large Magellanic Cloud (LMC) as a part of the AKARI Mission Program "Large-area Survey of the LMC" (LSLMC, PI: T. Onaka). An area of about 10 square degrees of the LMC was observed by five photometric bands (3.2, 7, 11, 15, and $24{\mu}m$) and a low-resolution slitless prism ($2-5{\mu}m$, R ~20) equipped with AKARI /IRC. We constructed and publicly released photometric and spectroscopic catalogues of point sources in the LMC based on the survey data. The catalogues provide a large number of near-infrared spectral data, coupled with complementary broadband photometric data. Combined use of the present AKARI LSLMC catalogues with other infrared point source catalogues of the LMC possesses scientific potential that can be applied to various astronomical studies.

Isolation of Magnolialide and Artesin from Cichorium intybus: Revised Structures of Sesquiterpene Lactones

  • Park, Hee-Juhn;Kwon, Sang-Hyuk;Yoo, Ki-Oug;Jung, Won-Tae;Lee, Kyung-Tae;Kim, Joo-Il;Han, Yong-Nam
    • Natural Product Sciences
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    • v.6 no.2
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    • pp.86-90
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    • 2000
  • Two known eudesmanolides, magnolialide and artesin, were isolated from the roots of Cichorium intybus. Their structures were confirmed by HMBC and NOESY NMR spectral interpretation. Therefore, guaianolides and eudesmanolides that have been previously reported should be revised.

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Studies on the Constituents of Chenopodium acuminatum (버들명아주의 성분(成分)에 관한 연구(硏究))

  • Kim, Chong-Won;Lee, Kyoung-Suk
    • Korean Journal of Pharmacognosy
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    • v.16 no.4
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    • pp.206-209
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    • 1985
  • White needle crystalline compound, mp.\;78{\sim}79$, was isolated from the petroleum ether fraction of the aerial parts of Chenopodium acuminatum. This compound was supposed to be cycloalkane by chemical properties, spectral data and elemental analysis. After extraction with petroleum ether, the methanolic extract of this plant found to contain aspartic acid, threonine, serine, glutamic acid, glycine, cystine, valine, isoleucine, tyrosine, and phenylalanine. Inorganic elements contained in this plant are as following: Mg 4.84%, Ca 9.602%, Zn 1.11%, K 29.104%, Mn 5.124%, Fe 27.039%, Co 0.31%, Pb 0.995%, Na 0.039% and Cu, 0.0076%.

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Tricuspid valve dysplasia complicated with pulmonic regurgitation in a Cocker Spaniel dog

  • Nam, So-Jeong;Choi, Ran;Park, In-Chul;Hyun, Changbaig
    • Korean Journal of Veterinary Research
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    • v.48 no.4
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    • pp.481-487
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    • 2008
  • A 17-month-old intact male Cocker Spaniel was presented with primary complaints of severe ascites, exercise intolerance, and diarrhea. Diagnostic studies revealed tricuspid and pulmonic regurgitation on phonocardiogram, right ventricular enlargement on the electrocardiogram, typical right cardiac enlargement signs on the thoracic radiography and tricuspid valve malformation and marked enlargement of the right atrium and right ventricle on the echocardiography and tricuspid and pulmonary regurgitation on the color spectral echocardiography, suggesting tricuspid valve dysplasia and pulmonary hypertension. Using angiography and cardiac catheterization, pulmonary hypertension was ruled out. Further echocardiographic study revealed membranous valvular structures cranial to pulmonary annulus causing pulmonary regurgitation. Based on these findings on the diagnostic investigation, the case was diagnosed as tricuspid valve dysplasia complicated with pulmonic regurgitation. The dog was medically managed with furosemide, enalapril, nitroglycerine transdermal patch and pimobendan after the ascitic fluid removal.

EXPERIMENTAL INVESTIGATION OF PRESSURE FLUCTUATIONS ON THE BED OF FLIP BUCKET SPILLWAYS

  • KAVIANPOUR M.R.;POURHASAN M.A.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.09a
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    • pp.590-591
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    • 2005
  • Hydrodynamic pressure fluctuations and their roles on the design of hydraulic structures has been the subject of many investigations. The studies showed that turbulent pressure fluctuations may cause serious damages to hydraulic structures. In case of high velocity flows, separation of flow from the boundary also causes the local pressure to drop and as a result, the resultant pressure fluctuations may trigger cavitation. Sever hydrodynamic pressures are also associated with the vibration of structures. Therefore, in this work, experiments were performed to determine the intensity of pressure fluctuations and their distribution along the bed of a ski-jump flip bucket. Experiments were completed on a physical model at the Institution of Water Research of Iran. The results consist of the statistical characteristics of pressure fluctuations, its maximum, minimum, and r.m.s values along the bed of the bucket. The spectral analysis of pressure fluctuations which is useful for the instability analysis of such structures is also provided. It is hoped that the present results will help the designer of such structures.

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The effects of high hell on back muscle fatigue (High Heel이 허리 근육 피로에 미치는 영향에 관한 연구)

  • 현수돈;김정룡
    • Journal of the Ergonomics Society of Korea
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    • v.16 no.3
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    • pp.37-48
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    • 1997
  • It is very common for women wear shoes with a high heel. It has been known that the high heel could disfigure the foot shape and cause various joint problems including back pain. However, few quantitative studies have been conducted. Therefore, in this study, the low back muscle has been investigated in order to find fatifue effect due to different heights of the heel. In particular, 0, 4, 6 and 8cm heel and two different shapes of heel have been used for an experiment. Ten healthy female subjects volunteered for the study. Isometric Trunk Exertion Frame(ITEF) and Electromyography were used to measure tha Median Frequency via Spectral analysis. The results indicated that the heel height significantly affected the local muscle fatigue of the back. After post hoc analysis, it was found that a proper heel height ougth to be lower than 5cm not to have severely fatigued back muscle after a casual walk for an hour. Such results could be applies to female industrial workers in order to prevent a cumulative trauma disorder of the back, and also to design a female dress shoes minimizing low back fatigue.

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Vegetation Classification from Time Series NOAA/AVHRR Data

  • Yasuoka, Yoshifumi;Nakagawa, Ai;Kokubu, Keiko;Pahari, Krishna;Sugita, Mikio;Tamura, Masayuki
    • Proceedings of the KSRS Conference
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    • 1999.11a
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    • pp.429-432
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    • 1999
  • Vegetation cover classification is examined based on a time series NOAA/AVHRR data. Time series data analysis methods including Fourier transform, Auto-Regressive (AR) model and temporal signature similarity matching are developed to extract phenological features of vegetation from a time series NDVI data from NOAA/AVHRR and to classify vegetation types. In the Fourier transform method, typical three spectral components expressing the phenological features of vegetation are selected for classification, and also in the AR model method AR coefficients are selected. In the temporal signature similarity matching method a new index evaluating the similarity of temporal pattern of the NDVI is introduced for classification.

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