• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.35-42
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• 2003

A 1,3 kb cellulase gene encoding novel bifunctional cellulase-chitosanase activity was cloned from biopolymer-producing alkali-tolerant B. lichenformis NBL420 in E. coli. A recombinant cellulase-chitosanase, named CelA, was expressed and purified to homogeneity. The activity staining and the enzymatic characterization of the purified CeIA revealed bifunctional activities on carboxymethyl cellulose (CMC) and glycol-chitosan. The similar characteristics of the enzymatic activities at the optimum pH, optimum temperature, and thermostability Indicated that CelA used a common catalytic domain with relaxed substrate specificity. A comparison of the deduced amino acids in the N-terminal region revealed that the mature CelA had a high homology with the previously identified bifunctional cellulase-chitosanase of Myxobacter sp. AL- 1.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.169-176
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• 2013

The price and revenue of rice are expected to decrease due to increasing rice imports, decreasing consumption and the discontinuance of the government's rice procurement. This degenerating profitability is leading to a rise in the cultivation of upland-crops such as beans, fodder crops and fruits in paddy fields. However, there is a lack of research on the selection of rice substitute crops which are adaptable to the relevant region through profitability analysis. This research, therefore, analyzed investment profitability of rice substitute crops for Cheorwon-gun area in Kangwon province. The study applied net present value (NPV) and internal rate of return (IRR), which fit for mutually exclusive investments that make one selection to the exclusion of other crops. Target crops are green house plants in Cheorwon-gun area. Financial analysis showed paprika and cucumber have investment feasibility for automated vinyl greenhouses and conventional plastic greenhouses respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.3
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• pp.210-216
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• 2013

Rotor blades experience mechanical loads caused by the turbulent wind shear and an impulse-like wind due to the tower shadow effect. These mechanical loads shorten the life of wind turbine. As the size of wind turbine gets bigger, a control system design for mitigating mechanical loads becomes more important. In this paper, individual pitch control(IPC) for the mechanical loads reduction of rotor blades in a transition wind speed region is introduced, and simulation results verifying IPC performance are discussed.

• Journal of the Korean Solar Energy Society
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• v.32 no.5
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• pp.31-40
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• 2012

This paper introduces a methodology for NREL 5MW wind turbine, which is the variable speed and variable pitch(VSVP) control system. This control strategy maximizes the power extraction capability from the wind in the low wind speed region and regulates the wind turbine power as the rated one for the high wind speed region. Also, pitch control efficiency is raised by using pitch scheduling.Torque schedule is made of torque table depending on the rotor speed. Torque control is used for vertical region in a torque-rotor speed chart. In addition to these, mechanical loads reduction using a drive train damper and exclusion zone on a torque schedule is tried. The NREL 5MW wind turbine control strategy is comprised by the generator torque and blade pitch control. Finally, proposed control system is verified through GH Bladed simulation.

• Journal of the Korean institute of surface engineering
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• v.52 no.6
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• pp.357-363
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• 2019

We investigated a synthesis yield and diameter distribution of single-walled carbon nanotubes (SWNTs) with respect to the growth position in a horizontal chemical vapor deposition (CVD) chamber. Thin films and line-patterned Fe films (0.1 nm thickness) were prepared onto ST-cut quartz substrates as catalyst to compare the growth behavior. The line-patterned samples showed higher growth density and parallel alignment than those of the thin film catalyst samples. In addition, line density of the aligned SWNTs at central region of the chamber was 7.7 tubes/㎛ and increased to 13.9 tubes/㎛ at rear region of the CVD chamber. We expect that the enhanced amount of thermally decomposed feedstock gas may contribute to the growth yield enhancement at the rear region. In addition, the lamina flow in the chamber also contribute to the perfect alignment of the SWNTs based on the value of gas velocity, Reynold number, and Knudsen coefficient we employed.

• Korean Journal of Microbiology
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• v.32 no.2
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• pp.115-119
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• 1994

Replication control region of pSBK203, a chloramphenicol acetyltransferase conferring plasmid from Staphylococus aureus was cloned and its nucleotide sequence has been determined. Base sequence homology of this copy control region with those of plasmids belonging to pT181 family was obtained and analyzed. Copy number of four copy mutants derived by addtion or deletion of nucleotides in unique XbaI recognition site in copy control region of pSBK203 was also determined.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.846-853
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• 2005

The whole death by disaster is totalized to 1,515 person from 1993 to 2004 year in our country. In this section life damages by landslide is totalized 357 people(about 24% of whole life damage). About 36 people are died by landslide(such as cutting area failure every year). Kangwon-do need a lot of interests and prevention because dangerous area that landslide occurrence is more than other area at summer localized downpour or thawing season and there is landslide occurrence possibility area more than other area. Kangwon-do area is higher than other area in natural disaster incidence and damage scale because topography and a lot of rainfalls by summer localized in Kangwon-Do than other area. In this study, dangerous area of landslide occurrence possibility is analyzed and compared Kangwon-Do with other areas in our country. as a result, every year we have experienced landslide occurrence and natural disaster. accordingly, we urgently need to prevent landslide occurrence and natural disaster by analy-zed source about landslide occurrence and condition of disaster in Kangwon-Do and suitable engineering method and construction work.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.30-30
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• 2015

This study was conducted aiming with the assessment of fungal diversity in soil samples collected from different locations of Jeollabuk-do and Chungcheongbuk-do, Korea. Forty soil samples were collected in 2015 and fungi were isolated through serial dilution technique. Isolated fungi were purified and differentiated according to their morphological and microscopic characteristics. In total, 150 different representative isolates were recovered and the genomic DNA of each isolate was extracted by using QIAGEN$^{(R)}$ Plasmid Mini Kit (QIAGEN Sciences, USA) and the identification of fungi was carried out by sequence analysis of internal transcribed spacer (ITS) region of the 18S ribosomal DNA (18S rDNA). Recovered isolates belonged to 37 family, 67 genera and 108 species. Aspergillus spp., Penicillium spp., Trichoderma spp., Chaetomium spp. And Fusarium spp. were the most dominant taxa in this study. Out of total species, 20 species were identified as new records for Korea.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.99-100
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• 2011

본 논문에서는 전압평면에서 표면 부착형 영구자석 동기전동기(Surface Mounted Permanent Magnet Synchronous Motor, SPMSM)의 전압과 전류 제한에 따른 운전 영역을 분석하고, 무한 속도 제한을 갖는 SPMSM에 적용 가능한 전압 궤환을 이용한 약자속 제어 기법을 제안한다. 제안된 기법은 시뮬레이션을 통해 그 타당성을 검증하였다.

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.23-32
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• 2008

Anatomical and physical characteristics of seven cultivars of chestnut wood (Castanea crenata Sieb. et Zucc.), Tanzawa, Ibuki, Mansung, Arima, Ginyose, Tsukuba, and Riheiguri, were investigated to obtain some valuable information for their possibilities to be used for high quality furnitures and woodcrafts. Solitary pore and figured-porous or ring-porous wood types were observed in wide growth rings, and ring-porous in narrow growth rings. Procumbent type was prevalent in ray cells although upright and square types were scarcely existed. Uniseriate, biseriate, and multiseriate rays were observed in tangential section. Uniseriate ray was abundant near the pith, and biseriate and multiseriate rays were frequently existed near the bark. The occurrence rate of biseriate and multiseriate rays was significantly high in Tanzawa, Ibuki, Mansung and Tsukuba, but was somewhat low in Arima, Ginyose and Riheiguri. The inner region showed larger vessel diameter, more vessel number, fewer ray number and higher ray height than the outer region. Growth-ring width in inner region was larger than that in outer region. Growth-rings in inner region of Mansung and Arima were wide while that of Ibuki was narrow. Outer region in all cultivars showed higher latewood percentage than inner region. Especially, Mansung and Tsukuba showed significantly high latewood percentage in their outer region. Green moisture content and density of heartwood were higher than those of sapwood. Tsukuba and Riheiguri had higher green moisture content, and Ibuki and Riheiguri had higher green density than the other chestnut cultivars.