• Title/Summary/Keyword: metX

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The Multipactor Test results on the X Band filter of Space Qualification Model appropriated for the Geostationary Satellite considering for space environments (우주환경을 고려한 정지궤도위성에 적합한 X대역 필터의 멀티팩터 시험 결과 연구)

  • Park, Jong-hee;Kim, Young-kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.65-68
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    • 2017
  • In this paper, a multipactor test for the space qualification model of the X-band dual-mode high-power channel filter for high-speed data transmission of geostationary satellite observation payloads was conducted and compared with the 8 dB margin required for design. It was confirmed that analytically required margins were met through testing and that satisfactory test results were obtained. The design and test of the multipactor are tested according to the ECSS standard. Based on this, it is suggested that if the margin of design is sufficiently secured, it can be used in the development of the filter for space qualification model without any test.

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Influence of Solidification Condition on the Segregation of SiC Particles in the Al-Si/$SiC_p$ Composites (Al-Si/$SiC_p$ 복합재료에서 SiC의 편석에 미치는 응고 조건의 영향)

  • Kim, Jong-Chan;Kwon, Hyuk-Moo
    • Journal of Korea Foundry Society
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    • v.17 no.2
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    • pp.180-187
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    • 1997
  • The influence of solidification condition on the segregation of SiC particles in the $Al-xSi/6wt%SiC_p$(x: 6, 10, 14, 18${\cdot}$wt%) composites was investigated in the study. The results are as follows: 1) During the counter-gravity unidirectional solidification of $Al-Si/SiC_p$ composites melt, most of the SiC particles are pushed to the top of the casting. 2) The SiC particles pushing in the $Al-Si/SiC_p$ composite melts are not observed, when the interface velocity of melts increases more than 1.41 ${\mu}m/sec$. 3) The SiC particles are entrapped in the interdendrite regions, when the sizes of SiC particles in the $Al-Si/SiC_p$ composites are large than ${\varphi}22{\mu}m$.

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Optimization of Heavy-Duty Diesel Engine Operating Parameters Using Micro-Genetic Algorithms (유전알고리즘을 이용한 대형 디젤 엔진 운전 조건 최적화)

  • Kim, Man-Shik;Liechty, Mike P.;Reitz, Rolf D.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.2
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    • pp.101-107
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    • 2005
  • In this paper, optimized operating parameters were found using multi-dimensional engine simulation software (KIVA-3V) and micro-genetic algorithm for heavy duty diesel engine. The engine operating condition considered was at 1,737 rev/min and 57 % load. Engine simulation model was validated using an engine equipped with a high pressure electronic unit injector (HEUI) system. Three important parameters were used for the optimization - boost pressure, EGR rate and start of injection timing. Numerical optimization identified HCCI-like combustion characteristics showing significant improvements for the soot and $NO_X$ emissions. The optimized soot and $NO_X$ emissions were reduced to 0.005 g/kW-hr and 1.33 g/kW-hr, respectively. Moreover, the optimum results met EPA 2007 mandates at the operating point considered.

PYRANOSE OXIDASE HAVING A COVALENTLY BOUND FAD AS A COENZYME

  • Kwon, Jae-Youl;Kang, Sa-Ouk
    • Proceedings of the Korean Biophysical Society Conference
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    • 1996.07a
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    • pp.45-45
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    • 1996
  • Flavin-peptides were purified from pyranose oxidase (EC 1.1.3.10) after tryptic- chymotryptic and tryptic digestion. The spectral and chromatographic properties of these flavin peptides showed that the FAD of pyranose oxidase appears to be bound, by way of the 8${\alpha}$-methylene group, to the N-l position of the imidazole ring of the histidine. Automated sequence analysis showed that the amino acid sequence of the tryptic-chymotryptic flavin-peptide from pyranose oxidase is Ser-Thr-X-Trp and that of the tryptic flavin-peptide is Met-Ser-Thr-X-Trp. (omitted)

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Biodegradation of Crude oil by Marine Bacterium Pseudomonas sp. CHCS-2 and Composition of the Biosurfactant (해양세균 Pseudomonas sp. CHCS-2에 의한 원유분해 및 생물유화제의 성분 분석)

  • 김학주;김봉조;하순득;황선희;공재열
    • KSBB Journal
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    • v.14 no.2
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    • pp.192-197
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    • 1999
  • marine bacterium Pseudomonas sp. CHCS-2 produced the biosurfactant in the culture broth which contained 2%(w/v) arabian light crude oil and the productivity of biosurfactant was increased with the addition of glucose. The crude oil in the culture broth was degraded by this strain and carbon chain of $_nC_{12}~_nC_{22}$ was completely degradaded during the incubation for 196 h. The crude biosurfactant was purified by Amberlite XAD-7, Sepharose CL-4B and DEAE-Sepharose CL-6B column chromatography. Therefore, 0.21g/L of the purified biosurfactnat was obtained. The purified biosurfactant was a type of lipoprotein and the molecular weight was estimated as 67kDa by SDS-PAGE. The lipid composition was identified as octadecanoic acid by gas chromatography/mass spectrometry. And then, the N-terminal amino acid sequence of the protein was determined as Ser-Val-lle-Asn-Thr-lle-X-Met-lle-Gly-Gln-Gln- and the sequence did not show homology to any other known lipoprotein. Therefore, the purified lopoprotein was predicted novel biosurfactant.

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Desmopressin responding female nephrogenic diabetes insipidus: a case report

  • Juyeon Lee;Hae Il Cheong;Jung Won Lee;Ki Soo Pai
    • Childhood Kidney Diseases
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    • v.26 no.2
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    • pp.107-110
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    • 2022
  • Nephrogenic diabetes insipidus, decreased ability to concentrate urine, with production of large amounts of urine, is caused by the refractory response of renal tubules to the action of antidiuretic hormone. This rare disorder, known as X-linked nephrogenic diabetes insipidus, is caused by a mutation in the AVPR2 gene. Because it is hereditary, most patients are male. This report highlights a case of nephrogenic diabetes insipidus in a 3-year 5-month-old female; upon presentation to the hospital, her symptoms included frequent urinationand consumptionof a significant amount ofwater,which had begun2 years ago. The results of blood tests showed increased levels of serum antidiuretic hormone, and sellar magnetic resonance imaging showed no abnormality. The results of the water restriction test and the desmopressin administration test confirmed the diagnosis of nephrogenic diabetes insipidus showing a partial response to desmopressin. The results of genetic testing indicated the presence of an AVPR2 mutation, a heterozygous missense mutation (p.Val88Met), suggesting inheritance of X-linked nephrogenic diabetes insipidus. This report describes a significant case of symptomaticX-linked nephrogenic diabetes insipidus in a female patient who showed a partial response to desmopressin.

Protoplast Fusion of Lactose Assimilating Yeasts (유당 자화 효모간의 원형질체 융합)

  • Choi, Won-Ki;Chun, Soon-Bai;Lee, Yong-Kyu;Bai, Suk;Lee, Jin-Jong;Lee, Hyang
    • Korean Journal of Microbiology
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    • v.26 no.3
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    • pp.188-196
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    • 1988
  • Intergeneric or intraspecific protoplast fusion between Saccharomyces cerevisiae X-2180-1A, Candida pseudotropicalis ATCC 8619 and CBS 607 was attempted to produce ethanol from lactose containing materials. Teh intergeneric fusion frequency between Saccharomyces cerevisiae X-2180-1A (ade rho) and Candida pseudotropicalis CBS 607 (his met) was $1.0\times 10^{-5}$. These values exhibited approximately 2-3.5 fold increase when compared with fusion frequency obtained without the treatment of bovine serum albumin, myoinositol and ergosterol, suggesting that these compounds may improve intergeneric of intraspecific protoplast fusion. Nuclear fusion appears to occur in fusants between intergenera(S. cerevisiae+C. pseudotropicalis) and intraspecies (C. pseudotropicalis strains) as strongly suggested by DNA content, nuclear staining, comparison of survival rate to UV light and isolation of recombinants after mitotic segragation. It was also found that alcohol production from intraspecific hybrids was somewhat increased when compared with that from their parents.

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Effects of Dietary Chromium Methionine on Growth Performance, Carcass Composition, Meat Colour and Expression of the Colour-related Gene Myoglobin of Growing-finishing Pigs

  • Li, Y.S.;Zhu, N.H.;Niu, P.P.;Shi, F.X.;Hughes, C.L.;Tian, G.X.;Huang, R.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.7
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    • pp.1021-1029
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    • 2013
  • To investigate the effect of dietary chromium (Cr) as Cr methionine (CrMet) on growth performance, carcass traits, pork quality, meat colour and expression of meat colour-related genes in growing-finishing pigs, 189 crossbred Duroc${\times}$(Landrace${\times}$Yorkshire) growing-finishing pigs (male, castrated, average initial BW $74.58{\pm}1.52$ kg) were selected and randomly allocated into four groups. Dietary treatments per kg of feed were as follows: 0 (CT), 0.3 mg/kg (T1), 0.6 mg/kg (T2) and 0.9 mg/kg (T3) Cr (in the form of CrMet; as-fed basis), and each treatment was replicated five times with 8 to 10 pigs per replicate pen. During the 28 d of the experiment, both the ADG and the ADFI increased linearly (p<0.05) as the level of dietary Cr increased. The F/G ratio decreased linearly (p<0.05). As dietary Cr increased, loin muscle areas (linear, p = 0.013) and average backfat thickness (linear, p = 0.072) decreased. Shear force (linear, p = 0.070) and Commission Internationale de I'$\acute{E}$clairage (CIE) redness (quadratic, p = 0.028) were increased. In addition, CIE Lightness (quadratic, p = 0.053) were decreased as dietary Cr increased. As dietary Cr increased, total myglobin (Mb) content (quadratic, p = 0.015) and the mb mRNA levels (quadratic, p = 0.046) in longissimus muscles of pigs were up-regulated. In conclusion, supplementation of dietary Cr improved growth and meat colour, but increased shear force and decreased IMF reduced palatability of longissimus muscles. Moreover, the increasing total Mb content and mb mRNA levels indicated that CrMet dietary supplementation may improve meat colour via up-regulating expression of the mb gene.

A Study on DNA Sequences and Mutation of Integrase Region of Korean-type Bovine Leukemia Virus (BLV) pol Gene

  • Kwon, Oh-Sik;Kang, Jung-Soon;Park, Hyun-Jin;Yoo, Min
    • Biomedical Science Letters
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    • v.10 no.1
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    • pp.55-63
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    • 2004
  • Bovine leukemia virus (BLV) is a causative agent for lymphoma disease in cattle including cows worldwide. BLV shares similar virion structure and characteristics with other retroviruses. The pol gene of the BLV genome produced reverse transcriptase (RT) and integrase (IN) for important roles for BLV genome integration into host cell chromosomes that is known to be coded in the 3' side of the BLV pol gene (one third portion). In this study, we have sequenced 978 bp in the 3' side of the BLV pol gene from BLV 10C3 in order to determine the BLV IN region of it. And we compared it to the nucleotide sequences of an Australian BLV isolate. As a result, nucleotide sequences of the IN region of the Korean-type BLV pol gene were mutated at a rate of 3.7%. We can confirm that the typical mutations are such as Arg (AGG) $\rightarrow$ Lys (AAG), Thr (ACG) $\rightarrow$ Met (ATG), Ile (ATT) $\rightarrow$ Val (GTT), Asn (ACC) $\rightarrow$ His (CAC), Phe (TTT) $\rightarrow$ Leu (TTG) and Asn (ACC) $\rightarrow$ Asp (GAC). From the analysis of the sequencing data, we were able to determine the zinc-finger-like "HHCC" motif in the amino terminus of BLV IN, that was H-$X_3$-H-$X_{25}-C-X_2$-C. It was also found the DD35E motif in the IN catalytic domain as D-$X_{56}$-D-$X_{35}$-E. It fits very well to the consensus sequences of retroviral IN as well as HHCC motif.

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Real-time Implementation of a Tone Sender/Receiver on a High Performance DSP (고성능 DSP를 이용한 톤 송수신기의 실시간 구현)

  • 최용수;함정표;조성범;강태익;윤정현
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.4
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    • pp.276-285
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    • 2003
  • In this paper, we present real-time implementation of a R2MFC/DTMF (R2 Multi Frequency Combinations/Dual Tone Multiple Frequency) tone receiver/sender using a high performance DSP (Digital Signal Processor) and apply it to a carrier class VoIP (Voice over Internet Protocol) gateway system. The Receiver utilizes the Goertzel filter and the sender adopts the harmonic resonant filter. We describe, in detail, the techniques of multi-channel real-time implementation on a Texas Instruments TMS320C62x DSP such as effective PCM (Pulse Code Modulation) in/out by means of DMA (Direct Memory Access) and McBSP (Multi Channel Buffered Serial Port) and message communication via HPI (Host Port Interface), etc. From experimental results, we confirmed that the optimized code provided 780 channel capacity at 250㎒ C6202, and the our R2MFC/DTMF receiver/sender met ITU-T (International Telecommunication Union-Telecommunication) specifications.