• 제목/요약/키워드: NgN

검색결과 693건 처리시간 0.033초

Study of Greitzer's B-Parameter Model Using ANOVA & Taguchi Method

  • Ng E. Y-K;Liu N.;Tan S. Y.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
    • /
    • pp.197-199
    • /
    • 2003
  • In this work, the Greitzer's B-parameter model is applied for analyzing the stall and surge characteristics. The four parameters in the model are highlighted in order to establish the influence of each parameter on the system. First of all, the governing equations of stall and surge behavior are solved numerically using fourth-order Runge-Kutta method. The Taguchi method is then used to analyze the results generated to obtain the extent of effects of the parameters on the system by varying the parameters in a series of combinations. Finally, a thorough analysis is carried out on the results generated from the Taguchi method and the graphs.

  • PDF

HPLC를 이용한 뇨 및 혈액중 Metocurine Iodide의 미량분석 (Microanalysis of Metocurine Iodide in Urine and Blood by HPLC)

  • 김경님;이종필;김효진;김박광
    • 약학회지
    • /
    • 제38권4호
    • /
    • pp.379-388
    • /
    • 1994
  • A new method for the analysis of metocurine iodide in biological fluids was developed. Metocurine iodide was quantitatively extracted with rose bengal from aqueous layer into dichloromethane layer and the amount of metocurine iodide was calculated from the amount of rose bengal which was determined by HPLC with fluorescence detector. It was possible to analyze metocurine iodide without the effect of co-prescribed drugs in the concentration range of $0.09{\sim}9.10\;{\mu}g/ml$. The detection limits of metocurine iodide in urine and blood were 0.8 and 1.2 ng at S/N=3, each respectively.

  • PDF

Resolution of Salbutamol Enantiomers in Human Urine by Reversed-Phase High Performance Liquid Chromatography after Derivatization with 2,3,4,6-Tetra-O-acetyl-${\beta}$-D-glucopyranosyl Isothiocyanate

  • Kim, Kyeong-Ho;Kim, Tae-Kyun
    • Archives of Pharmacal Research
    • /
    • 제21권2호
    • /
    • pp.217-222
    • /
    • 1998
  • A stereospecific HPLC method has been developed for the resolution of the enantiomers of salbutamol in human urine. After solid-phase extraction and derivatization with 2,3,4,6-tetra-O-acetyl-$\beta$-D-glucopyranosyl isothiocyanate, the diastereomeric derivatives were resolved (Rs=1.83) on $5{\mu}m$ octadecylsilan column using 35% acetonitrile in 0.05M ammonium acetate buffer (pH=6) as a mobile phase with electrochemical detection. The diastereomeric derivatives were formed within 30 min. The detection limit of each enantiomer was 20 ng/ml (S/N=3).

  • PDF

메틸 5-히드록시 디나프토 [1, 2-2', 3'] 푸란-7, 12 디온 6-카복시레이트의 미량분석 (Micro-Analysis of Methyl 5-Hydroxydinaphtho[1, 2-2', 3'] furan-7, 12-dione-6-carboxylate)

  • 박유미;장혜선;강경환;김경님;장성기;김박광
    • 약학회지
    • /
    • 제37권3호
    • /
    • pp.286-289
    • /
    • 1993
  • UV and high performance liquid chromatographic methods for the quantitative analysis of methyl 5-hydroxy-dinaphtho [1,2-2',3'] furan-7,12-dione-6-carboxylate(MHDDC) in urine and blood were developed. The correlation coefficients of the calibration curves of MHDDC in chloroform, methanol and dioxane solution were 0.999, 0.997 and 0.998, respectively. MHDDC was resolved within 15 min and had a detection limit of 2-5ng at S/N=3 by using a reversed-phase column with two solvents (MeOH, HAc).

  • PDF

한국어 비음의 음향학적 세부 기술을 위한 장구간 스펙트럼(LTAS) 분석 (Long Term Average Spectral Analysis for Acoustical Description of Korean Nasal Consonants)

  • 최순애;성철재
    • 대한음성학회:학술대회논문집
    • /
    • 대한음성학회 2006년도 추계학술대회 발표논문집
    • /
    • pp.92-95
    • /
    • 2006
  • The purpose of this study is to find the acoustic parameters on frequency domain to distinguish the Korean nasals, /m, n, ng/ from each other. Since it is not easy to characterize the antiformant on frequency domain, we suggest the new parameters that are calculated by LTAS(Long term average spectrum). Maximum energy value and its frequency and minimum energy and its frequency of zero are obtained from the spectrum respectively. In addition, slope1, slope2, total energy value, centroid, skewness, and kurtosis are suggested as new parameters as well. The parameters that are revealed as to be statistically signigicant difference are roughly peak1_a, zero_f, slope_1, slope_2, highENG, zero_ENG, and centroid.

  • PDF

Cost effective and low energy consuming hydrothermal synthesis of Ni based MOF

  • Israr, Farrukh;Kim, Duk Kyung;Kim, Yeongmin;Oh, Seung Jin;Ng, Kim Choon;Chun, Wongee
    • 에너지공학
    • /
    • 제24권2호
    • /
    • pp.51-54
    • /
    • 2015
  • The mesoporous metal organic framework structure of Ni-BTC was successfully synthesized in a low temperature and short operation time via hydrothermal synthesis process. Such operational route virtuously consumed less electrical and thermal energy. It proved time saving along with acceptable product yield (38%). The product was characterized through FESEM, FT-IR, XRD and $N_2$ gas adsorption measurement. Hightemperature stability of synthesized MOF was gauged by diffraction indexing of XRD patterns of as synthesized and heat treated samples of MOFs. The mathematically calculated particle size of Ni-BTC was found to be 42nm.

크라이신 7-O-크로토네이트의 물성 및 육모효과 (Properties and Hair-growth Effect of Chrysin 7-O-crotonate)

  • 신준수;김연희;정재훈;김양배;김박광
    • 약학회지
    • /
    • 제43권3호
    • /
    • pp.316-319
    • /
    • 1999
  • Chrysin 7-Ο-crotonate was synthesized by condensing crotonic acid with chrysin in organic solvent, tetrahydrofuran (THF) using dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP). Its structure was indentified by NMR, MS, UV, IR etc. We also investigated the physico-chemical properties and set up the quantitative anytical method of this compound. The correlation coefficient of calibration curve measured at the isobestic point (340 nm) on this compound was approximately 0.9994 by absorption spetrophtometry. Detection limit was 1.6ng at S/N=3 by using a RP column by HPLC. The hair growth effect fo chrysin 7-Ο-crotonate on the hair of black mouse (C57BL/6), was carried out using paste method. When its ethanol solution was administered to this black mouse by route of skin, this compound promoted the growth of hair.

  • PDF

조선조의 향교문고에 관한 연구 (A Study on the Hyang-Gyo Libraries In the Yi Dynasty)

  • 이춘희
    • 한국문헌정보학회지
    • /
    • 제5권
    • /
    • pp.1-30
    • /
    • 1978
  • The libraries of the various learning institutes in the Yi Dynasty may be categorized into four types: 1) The Hyang-Gyo library(the public school libraries in rural districts) 2) The Sabu-Hankdang library (the public school libraries in the Capital) 3) The $S\bar{o}w\bar{o}n$ library (the libraries of private learning institutes) 4) The $Jyon-Gy\bar{o}ng-Gak$ library (the library of the Sung Kyun Kwan which was the highest learning institute in the Yi Dynasty) For the historical study of Korean libraries as well as its education and culture the Hyang-Gyo libraries hold an very important position, but undeservedly its study has been neglected. In this paper, the writer made an effort to grasp the various function of the Hyang-Gyo libraries with its historical background.

  • PDF

반려견에서 혈중 Progesterone 농도 측정에 의한 분만일 예측 2. 분만예정일의 정확성 확인 (Prediction of Parturition Day by Determination of Plasma Progesterone Concentrations in Companion Bitches 2. To Confirm the Accuracy of the Prediction of Parturition Day)

  • 이주환;손창호
    • 한국임상수의학회지
    • /
    • 제37권6호
    • /
    • pp.305-310
    • /
    • 2020
  • To confirm the accuracy of the prediction of parturition day, the actual parturition days were compared with each day of the prediction of parturition day (n = 80). The accuracy of the prediction of parturition day was 80.0% (64/80) with a precision of ± 2 days from the first day of estrus after the first vaginal discharge, 97.5% (78/80) from the day when plasma progesterone concentrations increase above 4.0 ng/ml, and 72.5% (58/80) from the first day of diestrus, respectively. The accuracy of the prediction of parturition day by plasma progesterone concentration was higher than that by the first day of estrus and diestrus after the first vaginal discharge. These results indicated that the determination of plasma progesterone concentrations at estrus were a useful method for estimating of parturition day and for the reproductive management in pregnant bitches.

SUCCESS STORY OF THE SHIPBUILDING AND REPAIR INDUSTRY IN ACHIEVING EXCELLENT SAFETY PERFORMANCE: A LESSON FOR THE CONSTRUCTION INDUSTRY

  • Evelyn A.L. Teo;G. Ofori;Kelvin Y.N. Ng
    • 국제학술발표논문집
    • /
    • The 3th International Conference on Construction Engineering and Project Management
    • /
    • pp.896-906
    • /
    • 2009
  • In Singapore, the construction industry's performance in safety has often been the worst among the other industries. This paper seeks to compare the efforts of the shipbuilding and repair industry and the construction industry in improving the level of safety performance. One key factor identified in the paper will be the subcontractors' role in the safety aspect. Based on the analysis of statistic carried out by the Ministry of Manpower of Singapore and many others, this paper aims to identify the success of the shipbuilding and repair industry and gives thought as to how the construction industry can further improve its safety record.

  • PDF