• Journal of Positioning, Navigation, and Timing
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• 제7권3호
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• pp.175-181
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• 2018

The use of dual-frequency measurements from the Global Navigation Satellite System (GNSS) enables us to observe precise ionospheric total electron content (TEC). Currently, many GNSS reference stations in South Korea provide both GPS and GLONASS data. In the present study, we estimated the grid-based TEC values and relative receiver differential code biases (DCB) from a GNSS network operated by the Korea Astronomy and Space Science Institute. In addition, we compared the diurnal variations in a TEC time series from solutions of the GPS only, the GLONASS only, and combined GPS/GLONASS processing. A significant difference between the GPS only TEC and combined GPS/GLONASS TEC at a specific grid point over South Korea appeared near the solar terminator. It is noted that GLONASS measurements can contribute to observing a variation in ionospheric TEC over high latitude regions.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.81-84
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• 2003

Ethernet PON은 다수의 ONU(Optical Network Unit)가 하나의 OLT(Optical Line Terminator)를 공유하는 구조이며 수동 분배기를 사용하여 여러 가입자간 신호를 결합·다중화하여 고속 기간망에 전달하는 가입자망 기술이다. Ethernet PON에서 다수의 ONU들이 하나의 OLT로 정보를 전송하기 위해서는 ONU들이 먼저 등록이 되어야 한다. OLT가 등록을 허용하는 정보를 보내면 ONU가 등록을 시도하는데, 이 때 다수의 ONU가 시도를 하게 되면 충돌이 발생할 수 있다. 본 논문에서는 ONU의 초기 등록 과정과, ALOHA 프로토콜을 이용하여 ONU들이 등록을 시도할 때, 충돌 없이 등록을 성공적으로 수행하기 위해 필요한 프레임 수를 분석하였다. 초기 등록에서의 성공률을 검증하기 위하여 시뮬레이션을 실시하여 수학적 분석의 타당성을 확인할 수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권4호
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• pp.242-246
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• 2000

Human lipocortin-I was expressed as a secretory product by Saccharomyces cerevisiae harboring an expression system consisting of GAL10 promoter, inulinase signal sequence and lipocortin-I terminator. Fed-batch fermentation was carried out to overproduce recombinant human lipocortin-I. The culture medium was desalted and concentrated by ultrafiltration, and then subjected to hydroxyapatite column chromatography. The lipocortin-I was purified to >98% purity by single-step hydroxyapatite column chromato-graphy. However, it was found that the purified lipocortin-I was a proteolytically-cleaved form which was cleaved immediately after the basic amino acid Lys26.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.168-170
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• 2006

In this paper, authors realize water AMR(Automatic Meter Reading) network using low power ZigBee protocol included routing ability for improving wireless communitation error detection and network range. ZigBee wireless standard is an important standard of the field related Ubiquitous industry and recently has application to Home-Network. It's special features are to spend low power and to include routing ability each terminator. Because of these features, authors realize water AMR system on Embedded system using ZigBee protocol for applying to transfer data between a water meter and RF module equipped with a water meter in each house.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.543-547
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• 2002

DNA vaccines use eukaryote expression vectors to produce immunizing proteins in the vaccinated host and it represents a novel approach to vaccine and immuno-therapeutic development. We constructed a 2.9 kb compact plasmid vector (pVAC) which contains CMV promoter, polycloning site, BGH poly A terminator, ampicillin resistance gene and PBR322 origin. Enriched unmathlyated CpG motifs have introduced into pVAC-ISS1 and pVAC-ISS2 which are derived from pVAC for enhancing Thl responses. These plasmid DNAs rapidly induced interleukin 6 secretion in vivo. It is expected that these vectors will contribute to the DNA inoculation against infectious disease and various cancers without adjuvant.

• 디자인학연구
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• 제21권
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• pp.233-243
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• 1997

In 1970s, Computer Graphics of still and geometry changed computer Animation of image, and Computer Animation has diversely been used in movie, TV, fashion, sports, education, basic science, medical science, etc. by the development of LSI technology and the large size of computer in 1980s. Since Computer Animation was first used by movie of Futureworld in 1973, we easily experienced the essence of Computer Animation made of the Little Mermaid. Beauty and the Beast, the Lion King, Aladdin, etc. in Disney Animation and Terminator. Jurassic Park, the Mask, etc. in movie. And in other countries that have got the diversely special effect and knowhow in technology are effectively using the Computer Animation now. What situation we Korea are in now, if we compare the Computer Animation with that of other country using the progressive movie\ulcorner Although we first producted the movie title of Ticket, 10years ago, we have rarely been used it in movie, yet. Therefore, we know that it is very important for us to examine the historical and technical side for the purpose of overcoming the technological gap.

• Journal of Life Science
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• 제11권2호
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• pp.120-125
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• 2001

The pyrR gene of the pyrimidine biosynthesis (pyr) operon of the thermophile Bacillus caldolyticus, encoding a uracil phosphoribosyltransferase (UPRTase), turned to rely as a pyr operon regulator. It has been proposed that PyrR mediates transcriptional termination-antitermination at three intercistronic regions of the par operon (S.-Y Ghim and J. Neuhard, J. Bacteriol.,176, 3698-3707, 1994). In this research, a plasmid carrying the pyrR region of B. caldolyticus could restore a pyrimidine regulation in a pyrR mutant of B. subtilis. Expression of pyrR was found to increase 6-7 fold during pyrimidine starvation. Additionally, a highly conserved nucleotide sequence which may constitute the binding site for a PyrR protein (PyrR-binding loop) in transcript was staggested. Alternative antiterminator and terminator structures involving three conserved motifs in front of the pyrR, pyrP and pyrB genes, respectively, are proposed to account for the observed regulation pattern.

• Mycobiology
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• 제29권3호
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• pp.132-134
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• 2001

Since it is known that Agrobacterium tumefaciens, which has long been used to transform plants, can transfer the T-DNA to yeast Saccharomyces cerevisiae during tumourigenesis, a variety of fungi were subjected to transformation to improve their transformation frequency. In this study, I report the A. tumefaciens-mediated transformation of filamentous fungus Aspergillus niger. Transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator as a selectable marker, led to the selection of $50{\sim}100$ hygromycin B-resistant transformants per $1{\times}10^7$ conidia of A. niger. This efficiency is improved $10{\sim}20$ fold more than reported elsewhere. In order to avoid the difficulties in selection transformant from the over-growing non-transformant, I used top agar containing 900 ${\mu}g/ml$ of hygromycin. Genomic PCR and Southern analysis showed that all transformants contained single T-DNA insert per fungal genome. This technique offers an easier and more efficient method than that of using protoplast.

• 미생물학회지
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• 제33권2호
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• pp.86-91
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• 1997

Pseudomonas sp. DJ77로부터 클로닝된 glutathione S-transferase 유전자(phnC)의 염기서열을 결정하였다. 603bp의 open reading frame(ORF)이 존재하였고 개시코돈 앞에서 Shine-Dalgarno sequence를, 종결코돈 뒤에서는 terminator sequence를 발견하였다. phnC 유전자에서 만들어지는 phnC 단백질은 21,416 Da으로 SDS-polyacrylamide gel 전기영동 결과와 일치하였다. PhnC는 Bulkholderia cepacia LB400, Cycloclasticus oligotrophus RB1의 GST와 각각 53.7%, 49%의 높은 상동성을 나타냈다. 아미노산 서열의 상동성과 필수잔기들의 존재유무로 판단할 때 PhnC GST는 theta class GSTs와 진화적으로 유연관계가 높았지만 alpha, mu, pi, sigma class GSTs에서 구조적, 기능적으로 중요하다고 알려진 아미노산 잔기들이 PhnC GST에도 보존되어 있었다. 또한, phnC 유전자의 위치가 C. oligotrophus RB1, B. cepacia LB400 등의 GST 유전자 위치와 유사하다는 점에서 PhnC 효소는 난분해성 방향족 탄화수소의 분해에 관여하는 것으로 생각된다.

• 한국미생물·생명공학회지
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• 제33권4호
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• pp.241-247
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• 2005

선별마커로써 Lactococcus lactis ssp. lactis ATCC 7962 유래의 $\beta$-galactosidase 유전자를 포함하는 Lactococcus용 셔틀/발현 벡터 pWgall3T를 제조하여 Escherichia coli DH5$\alpha$와 고. Lactis MG1363내로 도입하였다. 이들 형질 전환체들은 X-gal을 포함하는 배지에서 파란색의 표현형을 보임으로써 쉽게 확인할 수 있었다. 또한, L. lactis MG1363 형질전환체로부터 $\beta$-galactosidase 활성을 측정한 결과 기존에 $\beta$-galactosidase를 활성을 지닌 L. lactis ATCC 7962에 비해 glucose를 포함하는 M17배지에서 4배정도 높은 활성을 보임으로써 선별마커로써의 효율성을 나타내었다. pWgal13T는 $\beta$-galactosidase 유전자 외에 L. lactis Wg2유래의 replicon과 외래 유전자의 발현을 위한 L. lactis ssp. cremoris LM0230의 promoter P13C, terminator를 포함하고 있다. 이 벡터의 이용가능성을 확인하기 위하여 외래 유전자 EGFP유전자를 P13C 아래에 삽입하여 E. coli와 L. iactis에서 발현을 확인하였다. 이 연구에서 제조된 Lactococcus용 발현 벡터 pWgal13T는 E. coli와 L. lactis에서 외래 유용 유전자를 생산을 위해 이용 할 수 있을 것이다.