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EVOLUTIONARY DESIGN OF NO SPIN DIFFERENTIAL MODELS FOR OFF-ROAD VEHICLES USING THE AXIOMATIC APPROACH

  • Pyun, Y.S;Jang, Y.D.;Cho, I.H.;Park, J.H.;Combs, A.;Lee, Y.C.
    • International Journal of Automotive Technology
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    • v.7 no.7
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    • pp.795-801
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    • 2006
  • A No Spin Differential (NSD) design has been improved from evaluation of two NSD models utilizing the axiomatic approach. New design parameters of the second level are developed to satisfy the independence axiom. The design matrices are determined to decouple the relationship between design parameters and process parameters. The values of process parameters are then determined to optimize and improve the NSD design. Consequently a unique and evolutionary NSD design is achieved with the aid of the axiomatic approach.

Development and Evaluation of an Electron Beam Source for Microscopy and Its Applications

  • Ahn, Seung-Joon;Oh, Tae-Sik;Kim, Ho-Seob;Ahn, Seong-Joon
    • Journal of the Optical Society of Korea
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    • v.14 no.2
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    • pp.127-130
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    • 2010
  • We have developed an efficient electron beam (e-beam) source, a microcolumn, that can be used as a source module for of microscopy and its applications. To obtain a low operating voltage, a very sharp cold field electron emitter was developed by electrochemically etching a tungsten wire. Laser diffraction was used for the fabrication of high-quality electron lenses and for their precise alignment. The measurement of the e-beam currents, and SEM images captured by the microcolumn confirmed the potential of the device as a very good e-beam source.

Control of Ultrasonic Motor Using Two-Phase High Frequency Inverter (2상 고주파 인버터에 의한 초음파 모터 제어)

  • Heo, J.Y.;Cho, G.B.;Baek, H.L.;Oh, K.G.;Jeung, H.S.;Yu, K.J.
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.462-464
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    • 1994
  • In this paper, noble electrical equivalent circuit ultrasonic motor is applied by model of parallel one from mechanical equation of piezoelectric device and characteristics estimation is done by equivalent converter. Uitrasonic motor is driven by oscillation circuit of two-phase high frequency inverter. Operating frequency of inverter is described by tracking control method of resonance frequency, according to change of load, temperature etc.

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Cystocin, a Novel Antibiotic, Produced by Streptomyces sp. GCA0001: Production and Characterization of Cystocin

  • Sohng, Jae-Kyung;Lee, Hei-Chan;Liou, Kwang-Kyoung;Lee, Eui-Bok;Kang, Sun-Yub;Woo, Jin-Suk
    • Journal of Microbiology and Biotechnology
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    • v.13 no.4
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    • pp.483-486
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    • 2003
  • 3'-[S-Methyl-cysteinyl]-3'-amino-3'-deoxy-N,N- dimethyl adenosine, cystocin, is a biosynthesized antibiotic material newly identified from Streptomyces sp. GCA0001. Its structure was found to be similar to puromycin, where the terminal tyrosine is replaced by a methyl cysteine. NMR data prove that the 3-ammo ribose is connected to dimethylaminopurine through the anomeric carbon at 1'-carbon. The methyl cysteinyl unit is connected to the amino unit of ribose by peptide bond. The verification of the structure was performed by comparing the puromycin nucleosides resulted from the hydrolysis of cystocin and puromycin, respectively. Antibiotic activity of cystocin against Streptococcus was found to be two times more potent than that of puromycin.

Bioconversion of Tetracycline Antibiotics to Novel Glucoside Derivatives by Single-Vessel Multienzymatic Glycosylation

  • Pandey, Ramesh Prasad;Chu, Luan Luong;Kim, Tae-Su;Sohng, Jae Kyung
    • Journal of Microbiology and Biotechnology
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    • v.28 no.2
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    • pp.298-304
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    • 2018
  • The single-vessel multienzyme UDP-${\alpha}$-$\text\tiny{D}$-glucose recycling system was coupled with a forward glucosylation reaction to produce novel glucose moiety-conjugated derivatives of different tetracycline antibiotic analogs. Among five tetracycline analogs used for the reaction, four molecules (chlorotetracycline, doxytetracycline, meclotetracycline, and minotetracycline) were accepted by a glycosyltransferase enzyme, YjiC, from Bacillus licheniformis to produce glucoside derivatives. However, the enzyme was unable to conjugate sugar units to rolitetracycline. All glucosides of tetracycline derivatives were characterized by ultraviolet absorbance maxima, ultra-pressure liquid chromatography coupled with photodiode array, and high-resolution quadruple time-of-flight electrospray mass spectrometry analyses. These synthesized glucosides are novel tetracycline derivatives.

Studies on Stability of Ftorafur (항암제제(抗癌製劑) 개발(開發)에 관(關)한 연구(硏究) -Ftorafur의 안전성(安定性)에 관(關)한 연구(硏究)-)

  • Baik, Chia-Sun;Choi, Jun-Shik;Yu, Young-Jong
    • Journal of Pharmaceutical Investigation
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    • v.15 no.1
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    • pp.40-44
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    • 1985
  • The stability of ftorafur in artificial gastric juice and its major decomposition product were studied quantitatively by the combination of TLC technique and UV-recording spectrophotometry. The decomposition proceeded in first-order reaction. The decomposition rate was accelerated by the increase of temperature. The major decomposition products were identified as 5-fluorouracil. The apparent activation energy for the decomposition was found to he approximately 24.3kcal/mole from Arrhenius plot.

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DESIGN EVALUATION OF NO SPIN DIFFERENTIAL MODELS USING THE AXIOMATIC APPROACH

  • Pyun, Y.S.;Jang, Y.D.;Cho, I.H.;Park, J.H.;Combs, A.;Lee, Y.C.
    • International Journal of Automotive Technology
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    • v.7 no.5
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    • pp.595-601
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    • 2006
  • Two No Spin Differential(NSD) models were benchmarked for a project of Dual-Use Technology. The Axiomatic approach is utilized to evaluate the designs of the models. The Independence Axiom is satisfied at the top level of design but not at the second level, which implies the design exhibits coupling and will admit design improvements. The detailed process of design evaluation is described. It is shown that it is possible to develop a unique and evolutionary NSD design by solving the problems that cause coupling within two models.

Combined Effect of Fluorouracil with Metoclopramide or Propantheline Bromide in Rats and Rabbits (Fluorouracil과 Metoclopramide 및 Propantheline.Bromide와의 병용시(倂用時) 항암효과(抗癌効果)에 관한 연구(硏究))

  • Choi, Jun-Shik;Lee, Jin-Hwan;Baik, Chai-Sun
    • Journal of Pharmaceutical Investigation
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    • v.14 no.1
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    • pp.11-18
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    • 1984
  • This paper was attempted to study on the effect of metoclopramide or propantheline on the absorption rate and bioavailability and pharmacokinetic parameter of fluorouracil in rats and rabbits. The result are as follows; Metoclopramide increased the absorption rate of fluorouracil but propantheline decreased in situ experiment with rat small intestine. Metoclopramide increased the blood level and relative bioavailability and absorption rate constant of fluorouracil in rabbits. Prolonged the peak blood level (tmax) and decreased the absorption rate constant (Ka) but did not affect the blood level and relative bioavailability of fluorouracil in rabbits. As a matter of fact, it is considerd that the coadministration of metoclopramide or propantheline is more desirable than the single administration of fluorouracil for available dosage regimen.

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Change in Blood Glucose Value of Rectal Administration of Liposome-Insulin to Rabbits (Liposome-Insulin의 토끼직장투여(直腸投與)에 있어서 혈당치(血糖値)의 변화(變化))

  • Kim, Sung-Ho;Choi, Jun-Sick;Back, Chae-Sun
    • Journal of Pharmaceutical Investigation
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    • v.12 no.3
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    • pp.88-92
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    • 1982
  • Insulin administration rectally with the liposome has the hypoglycemic effect in the rabbits. The reducton in blood sugar was maximum at about 60 minutes after administration and continued for 4 hrs. at low level in these experiments. No hypoglycemic effect was observed in control administrated rectally without liposome. Rectal absorption of insulin has been effected by addition of the bile salt, as the protective agent which prevented denaturation and the phastransition of insulin in liposome-encapsulation. As a matter of the fact, a significant hypoglycemic action was obtained when the insulin-liposome was given by rectal administration. The use of this agent to enhance insulin absorption offers the possibility of a new approach to rectal insulin therapy.

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SUN TRANSIT OUTAGE CONSIDERING SOLOR ACTIVITY AND IT'S APPLICATION TO KOREASAT (태양활동을 고려한 태양간섭현상 연구와 무궁화 위성에의 응용)

  • 노경민;최규홍;배석희
    • Journal of Astronomy and Space Sciences
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    • v.16 no.1
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    • pp.53-60
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    • 1999
  • The purpose of this paper is to predict Sun Transit Outage phenomenon(Sunout). Sunout had been studied mainly for the case of Geostationary satellite and under the assumption of 'Quiet Sun'. In this paper, we predict sunout phenomenon more precisely for non-geostationary orbit as well as geostationary orbit and specially we considered the degree of solar activity. And we compare the result of the case of C-band and Ku-band. Also the result is applied to the two KoreaSat communication system through calculating the link budget.

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