• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.181-184
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• 1996

This paper deals with the design problem of model reference adaptive controllers for MIMO plants with unknown orders. A design scheme for an adaptive control system based on CGT theorem, which has hierarchical structures derived from backstepping strategies, is proposed for MIMO plants with unknown orders but with known relative MacMillan degrees(relative degrees for SISO plants). It is also shown that all the signals in the resulting control system are bounded, and that the asymptotic tracking is achieved in the case where reference inputs are step.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.4
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• pp.377-387
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• 2012

An intrinsic small signal equivalent circuit model of Cylindrical/Surrounded gate MOSFET is proposed. Admittance parameters of the device are extracted from circuit analysis and intrinsic circuit elements are presented in terms of real and imaginary parts of the admittance parameters. S parameters are then evaluated and justified with the simulated data extracted from 3D device simulation.

• Journal of Microbiology and Biotechnology
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• v.12 no.6
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• pp.1002-1005
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• 2002

The effects of GroEL/ES chaperone on the production of soluble form of B. macerans cyclodextrin glucanotransferase (CGTase) in recombinant E. coli were investigated. The cgt gene and groEL/ES genes are under the control of T7 promoter and Pzt-1 promoter, respectively. The optimal concentrations of inducers, IPTG and tetracycline, were found to be 1.0 mM and 10 ng/ml, respectively. When tetracycline and IPTG were added at the early exponential phase (2h) and exponential phase (3h) of growth, respectively, about 1.5-fold increase of soluble CGTase activity and 1.6-fold increase of soluble CGTase protein were obtained. An SDS-PAGE analysis revealed that about $37.2\%$ of total CGTase protein was in the soluble fraction when GroEL/ES chaperone was overexpressed.

• JOURNAL OF ELECTRICAL WORLD
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• s.255
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• pp.76-83
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• 1998

대용량 파워일렉트로닉스기기의 보다 대용량화$\cdot$소형경량화 및 저손실화 요구에 응하기 위하여 조지전압 4.5KV, 가제어전류 4KA의 고내압$\cdot$대용량 CGT(gate commutated turn-off : 게이트 전류형 턴오프) 사이리스터를 개발하여 상품화하였다. GCT사이리스터는 대용량 파워일렉트로닉스기기의 키파트로서 폭넓게 사용되고 있는 GTO(Gate turn-off)사이리스터와 Turn-on동작이 같고 gto사이리스터의 이점이 저On전압특성을 그대로 갖는 한편 턴오프동작은 ''턴오프 게인이 1''인 새로운 원리에 기초하고 있으며 턴오프특성에서는 GTO사이리스터에 비해 다음과 같은 특징을 갖고있다. (1)GTO사이리스터응용에서 턴오프시 dv/dt를 억제하기 위하여 필요한 스나버회로가 없어도 턴오프동작이 가능하다. (2)축적시간을 종래 GTO사이리스터의 약 1/10로 저감할 수 있다. (3)게이트축적전하를 종래의 GTO사이리스터의 약 1/2로 저감할 수 있다. 이러한 턴오프특성에 의하여 GCT사이리스터는 대용량 파워 일렉트로니스기기에 스나버회로 손실발생의 억제에 의한 손실의 저감, 고속동작화, 직병렬접속 응용에 의한 대용량화의 용이성, 게이트구동회로의 용량을 반감하는 등 많은 메리트를 가져다 준다.

• Journal of Life Science
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• v.12 no.6
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• pp.688-693
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• 2002

Molecular chaperones prevent the misfolding of newly synthesized polypeptides in the cell. The coexpression of molecular chaperones could be expected to improve the production of soluble and active recombinant proteins. In this study, the effect of coexpression of E. coli GroEL/ES chaperone on the active production of Bacillus macerans cyclodextrin glucanotransferase (CGTase) in E. coli was investigated. Two plasmids, pTCGT1 and pGro7 in which the cgt and the groEL/ES genes are under the control of 77 promoter and araB promoter, respectively, were co-transformed into E. coli. With a series of cultures of recombinant E. coli cells, the optimal concentrations of IPTG and L-arabinose were found be 1 mM and 0.3 mg/$m\ell$, respectively. When IPTG and L-arabinose were added at 0.8~1.0 $OD_{600}$ and 0.4~0.5 $OD_{600}$, active CGTase production was increased significantly. This coexpression condition resulted in 1.5-fold increased level of soluble CGTase (0.7~0.73 unit/$m\ell$), compared to the level of CGTase in the single expression (0.36~0.56 unit/$m\ell$). An SDS-PACE analysis revealed that about 33.6% of CGTase in the total CGTase protein was found in the soluble fraction by coexpression of GroEL/ES chaperone.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.1
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• pp.23-34
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• 2016

Purpose: In the present study, the effect of circle contact lenses wear on contrast sensitivity and glare sensitivity in a refractive surgery group was investigated. Methods: The contrast sensitivity and glare sensitivity were evaluated using by CGT-1000 for a non-refractive surgery group as control group(40 eyes) and a refractive surgery group(30 eyes) applied plano circle contact lenses, and pupil size was also measured. The correlation between contrast/glare sensitivity and the pupil size was analyzed. Results: In the refractive surgery group, contrast sensitivity in the range of high spatial frequency decreased with wearing circle contact lenses, and amount of decrease for the refractive surgery group was larger than for the control group. The correlation between pupil size and the change of contrast sensitivity was decreased by wearing circle contact lenses, and the correlation was lower in the refractive surgery group than the control group. Furthermore, the wear of circle contact lenses affected on glare sensitivity. In analyzing the change of glare sensitivity by pupil size, the glare was larger in the refractive surgery group than control group. Circle contact lenses in refractive surgery group were not fitted on the center of cornea. Conclusions: In the present study, it is suggested that the sufficient understanding and consideration about the decrease of contrast sensitivity and the increase of glare by wearing circle contact lenses after the refractive surgery is necessary.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.118-123
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• 2005

For the expression in Saccharomyces cerevisiae, Bacillus stearothermophilus cyclodextrin glucano­transferase gene (cgtS) in pCGTS (4.8 kb) was subcloned into the surface expression vector, pYD1 (GALl promoter). The constructed plasmid, pYDCGT (7.2 kb) was introduced into S. cerevisiae EBY100 cells, and then yeast transformants were selected on the synthetic defined media lacking tryptophan. The formation of cyclodextrin (CD) was confirmed with active staining of culture broth of transformant grown on starch medium. Enzymatic reaction products with respect to the culture time and the reaction time were examined by TLC analysis. The results indicated that the enzyme activity was exhibited after 12 h cultivation and CD was produced after 10min of enzymatic reaction. When the surface-engineered yeast cells were cultured on galactose medium, maximum activities of CGTase were about 21.3 unit/l and 16.5 unit/l at $25^{\circ}C\;and\;30^{\circ}C$, respectively. The plasmids stability showed about $80\%\;even\;at\;25^{\circ}C\;and\;30^{\circ}C$.

• Journal of Life Science
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• v.14 no.1
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• pp.121-125
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• 2004

The synergistic effect of lowered incubation temperature and CroEL/ES expression on the production of soluble form of B. macerans cyclodextrin glucanotransferase (CGTase) was studied in recombinant E. coli. pTCGTl and pGroll carrying the cgt and groEL/ES genes under the control of T7 promoter and pzt-I promoter, respectively, were co-introduced. Tetracycline (10 ng/ml) and IPTG (1 mM) were added at the early-exponential phase (2 hr) and mid-exponential phase (3 hr). Low temperature cultivation at $25^{\circ}C$ with groEL/ES expression improved the activity of CGTase by two fold, compared to $37^{\circ}C$ cultivation without chaperones. SDS-PACE analysis revealed that about 69% of CGTase in the total CGTase protein was found in the soluble fraction by overexpression of GroEL/ES and cultivation at$25^{\circ}C$, whereas 20% of CGTase was detected in the soluble fraction when E. coli was cultivated at $37^{\circ}C$ without chaperone. The amount of soluble CGTase from $25^{\circ}C$ culture with chaperone was 3.5-fold higher than that of $37^{\circ}C$ culture without chaperone. Therefore the expression of CroEL/ES and low temperature cultivation greatly enhanced the soluble production of CGTase in E. coli.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.37-45
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• 2010

WEB or Internet has given mankind an unprecedented experience in indefinite sharing of online content by original means of digitalized information, but it comes to face an empirical issue of unreasonable informational superfluity as well as a practical issue of collapsed dot.com bubble economy in 2001. Instead, a latest networking concept called 'WEB 2.0' or 'Semantic WEB' becomes embodied as a new approach to entities such as end users and content. The concept of WEB 2.0 for creating a platform on the basis of openness and collaboration has made such a technological setting that we can effectively resolve and manage unreasonable data maintenance and interface inherent in Creative Group Thinking System (CGTS), a WEB-based computer-aided idea generation system developed in 2003. Concerning decreased usability and difficulties with data maintenance due to certain issues of CGTS as a part of WEB R&D platform, such as complex display composition and inefficient data processing system, this study seeks to simplify and streamline data structure by means of AJAX and DOM as WEB2.0-based technologies, and integrate interface structure of WEB platform to focus on end users, so that it can improve interface of conventional CGTS for the purpose of realizing end user's participation through improving usability.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.230-233
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• 1999

A plasmid vector was constructed for the expression and secretion of Bacillus macerans cyclodextrin glucanotransferase (CGTase) in Bacillus subtilis. The vector, pUBACGT, was composed of the ribosome-binding sequence, signal sequence, and cgt gene from B. macerans under the control of amyR2, the promoter of amyE gene coding for $\alpha$-amylase from B. subtilis var. natto. Bacillus subtilis LKS88, a mutant strain lacking genes for an amylase and two proteases, was used as a host for the transformation of the plasmid vector. The transformants were selected on kanamycin-containing Luria-Bertani plates. The starch hydrolyzing activity was observed on the starch-containing plates by the iodine method and cyclodextrin-forming activity was detected in the culture medium. A SDS-PAGE analysis showed that most of the expressed CGTase in the recombinant B. subtilis was secreted into the medium at a high expression level.