• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.271-276
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• 1985

Effects of media and its components on callus induction and plant regeneration were studied to increase the cultural efficiency in rice anther culture. The N$_{6}$ basic medium gave better results in callus induction than those of MS or Miller. The medium used for callus induction affects the plant regeneration. The frequency of plant regeneration from callus grown on Miller basic medium was lower than those of N$_{6}$ or MS. Most of calli derived from anthers, above 90%, were induced from 20 days to 40 days after anther inoculation. The cultural efficiency of modified N$_{6}$ basic medium which was composed of 31.5mM KNO$_3$ and 1.75mM(NH$_4$)$_2$SO$_4$ as nitrogen sources was higher than those of N$_{6}$ basic medium. Combination of NAA and Kinetin showed better results than that of 2, 4-D only in cultural efficiency. Effect of DL-alanine on callus induction in Indica variety, IR40, showed better response in the anthers pretreated for 6 days at 12$^{\circ}C$.

• Korean Journal of Microbiology
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• v.27 no.3
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• pp.216-220
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• 1989

As the bsic study about protoplast fusion of amylolytic fungus Aspergillus oryze and nonamyloytic sugar fermenter, Saccaromyces cerevsisae, the intraspecific protoplast fusion of A. oryzae was carried out and the properties of the obtained fusants were investigated. For protoplast fomation from mycellia of auxotrophs, Novozyme 234 as lytic enzyme was the most effective and optimal pH was determined to be pH 5.5-6.0. When the two types of protoplasts were treated with a fusogen including 30% PEG4000, they fused effectively and most of fusants were heterokaryons. Protoplasts aggregated with 30% PEG4000 after fusion treatment were observed by the microscope. Protoplast regeneration frequency was 1.46 to 13.8% and complementation frequency of fusion was 0.12 to 0.16. Fusant strains had a 1.5-fold DNA content compared to that of parent strain. And amylase activity was intermediate between those of parent strains.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.163-173
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• 2018

This paper performed the prediction of the acoustic loads applied to the surface of the flight vehicle during flight. Acoustic loads during flight arise from the pressure fluctuations on the surface of body. The conventional method of predicting the acoustic loads in flight uses semi-empirical method derived from theoretical and experimental results. However, there is a limit in obtaining the flow characteristics and the boundary layer parameters of the flight vehicle which are used as the input values of the empirical equation through experiments. Therefore, in this paper, we use the hybrid method which combines the results of CFD (Computational Fluid Dynamics) with semi-empirical methods to predict the acoustic loads acting on flight vehicle during flight. For the flight vehicle with cone-cylinder-flare shape, acoustic loads were estimated for the subsonic, transonic, supersonic, and Max-q (Maximum dynamic pressure) condition flight. For the hybrid method, two kind of boundary layer edge estimation methods based on CFD results are compared and the acoustic loads prediction results were compared according to empirical equations presented by various researchers.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.104-104
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• 1997

본 실험은 신경독성물질을 이용하여 선조체도파민신경찰성을 충분하게 손상시키고 도파민효능약물투여 후 유발되는 특정행동이 basal ganglia에서 발생되는 진행성이며 퇴행성신경질환인 파킨슨씨 질환(Parkinson's disease : PD)의 연구에 기여할 수 있는지의 타당성을 검토하고자 하였다. 흰쥐의 왼쪽선조체에 6-OHDA 8,16 and 24$\mu\textrm{g}$/2${\mu}\ell$(in 0.1% ascorbic acid)를 각각 투여하여 효율적으로 상동행동을 발현하는 신경독성물질의 투여 용량을 검토하고 도파민신경에 작용하는 약물의 투여방법(반복투여), 관찰기간(수술후 1주부터 4주간) 및 투여시기(7,21 및 35주령)에 따른 행동발현의 특성을 비교검토하고 아울러 성별의 영향도 검토하였다.

• Aerospace Engineering and Technology
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• v.2 no.1
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• pp.133-139
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• 2003

Position and trajectory data in-flight rocket are important informations to determine flight safety of rocket. In general tracking system, radar and transponder are used to acquire position information. Rocket position and trajectory can be determined by RF communication between ground station and in-flight rocket, and antenna position date. In this paper, it explains the ranging system which is low resolution rather than radar system but system configuration is simple. Therefore this system is useful for experimental flight vehicle.

• Convergence Security Journal
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• v.7 no.3
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• pp.31-37
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• 2007

There are many investigations about the security on RFID system to protect privacy. It is important to mutual authentication of the security on RFID system. The protocol for mutual authentication use light-weight operation such as XOR operation, hash function and re-encryption. However, the protocol for authentication and privacy is required more complicated cryptography system. In this paper, we propose a mutual authentication protocol using finite field GF($2^n$) for a authentication and are a safety analysis about various attacks.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.521-526
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• 2014

현대에 이르러 초경량 무인 비행기에 대한 많은 연구가 진행되고 있다. 이러한 비행체는 저레이놀즈수 영역에서 사용되는 특성으로 인해, 경계층 내에서 박리현상과 난류영역으로의 천이 등과 같은 여러 복합적인 현상을 발생시킴으로써 비행체의 공력특성에 큰 영향을 미친다. Bumpy Airfoil은 저레이놀즈수 유동에서의 이와 같은 문제를 해결하기 위해 제안된 익형이다. 따라서 본 논문은 전산열유체해석 프로그램인 EDISON_전산열유체를 이용하여 Bumpy Airfoil 형상에 대한 공력특성을 연구하였고, 발생하는 양항비를 원 익형과 비교하였다. 비압축성 조건 내에서, 공력 성능 향상을 위한 Bumpy Airfoil의 형상 변수로 Bump 개수와 높이를 선정하여 받음각에 따른 유동장을 분석하고 양항비를 수치해석 및 고찰하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.11a
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• pp.505-508
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• 2004

본 논문은 동적 3-D 뉴로 시스템(A Dynamic 3-D Neuro System)모델을 이용하여 오프라인 필기체 숫자 인식 실험을 하였다. 3-D 뉴로 시스템 모델을 사용함으로써 기존에 교육된 정보를 유지하면서 새로운 정보를 추가할 수 있는 추가학습이 가능했고, 동일한 범주의 정보에 대해서는 반복교육 횟수에 따라 교육정도가 점점 누적되는 반복교육이 가능했다. 교육과정을 통해 누적된 정보로부터 일반화된 패턴(Generalized Pattern)을 도출해 인식시 사용할 수 있었다. 패턴 인식기는 피드백루틴을 통해 미지의 입력이미지를 원형이미지로 복원한 후, 그 결과 데이터를 사용하여 문자를 인식하도록 동작한다. NIST의 MNIST 데이터베이스를 사용해 실험을 하였고, 결과로 $99.0\%$의 정인식률을 얻었다.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.638-640
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• 2003

최근 바이오인포매틱스 분야의 발전에 따라 방대한 양의 유전체 데이터에 대한 연구가 진행되고 있으며, 이러한 데이터를 효율적으로 다루기 위해 다양한 형태의 파일과 데이터베이스들이 사용되고 있다. 하지만 표준화의 미비로 인하여 데이터의 관리와 변환에 어려움이 많다. 본 논문에서는 이러한 문제점을 해결하기 위하여 바이오인포매틱스 데이터를 다루기 위한 표준으로 다양한 XML 포맷들 중에서 BSML(Bioinformatic Sequence Markup Language)을 채택하고, Genbank 파일을 변환하여 관계형 데이터베이스에 저장하는 모듈을 개발한다. 또한 관계형 데이터베이스 형태의 유전체 데이터를 BSML 형태로, Genbank 파일 형태를 BSML 형태로 그리고 AGAVE(Architecture for Genomic Annotation)파일 형태를 BSML 형태로 변환하는 변환기롤 개발하고자 한다.

• Membrane Journal
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• v.14 no.1
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• pp.57-65
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• 2004

The effect of porous support layer resistance and PDMS (polydimethylsiloxane) coating thickness on ethylene/nitrogen separation of composite membranes was studied with the model of Pinnau and Wijmans〔1〕. To control the support resistance (or permeance), PES porous membranes were prepared by phase inversion process with various PES/NMP dope concentrations. The thickness of selective PDMS top layer was controlled by using a spin coater. Its cross-section and coating thickness were observed by scanning electron microscope (SEM). Pure gas permeation test was done with ethylene and nitrogen, respectively. The experimental result for olefin/nitrogen separation process matched well with theoretical result from the model used. The result shows that optimization between PDMS coating thickness and support resistance is important to get PDMS composite membranes with best performance.