• 환경생물
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• 제18권4호
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• pp.441-446
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• 2000

Trichoderma harzianum is an aggressive causal agent of green mold disease on mushroom cultivation. Some bacterial strains isolated, from oyster mushroom compost in Wonju, were found to have in vitro antifungal activity against Trichoderma harzianum ATCC 6385, 6504, and our isolates Trichoderma spp. Y and G. Further in vitro antifungal studies on several strains of phytopathogenic fungi showed that all of 12 phytopathogenic fungal strains were significantly inhibited by the isolated antifungal bacteria in Petri dishes. Of these, KATB 99121 showed the broadest inhibiting effect and displayed as negative coagulase, negative sulfide production and rod shape. KATB 99121 was resistant to ampicillin, chlorampenicol, and kanamycin. Identification of isolates was determined by Biolog GN system, and KATB 99121 was identified as Photobacterium logei because of 96 probability, 0.65 similarity, and 4.97 disturbance. With electron microscopy, thin section of KATB 99121 strain revealed typical rod-like shaped cell (0.6-0.8${\mu}{\textrm}{m}$$\times$1.5-2.0${\mu}{\textrm}{m}$) with prokaryotic structure and organization.

• 동력기계공학회지
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• 제10권1호
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• pp.71-76
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• 2006

This paper aims to study several type heaters which are mica heater, film heater, quartz heater and rod heater and to get an temteraturel and electrical characteristics. These four type heaters have a merit in many fields than present electric heater with nichrome wire. Carbon and mica plate heater have higher heat efficiency and less electromagnetic waves. Also it has been reported that far infrared ray emission from this heater is good for our health. Additionally heating element is thin and lighter plate. For these reasons, they will be widely used to various application such as room-heating or manufacturing goods. Experimental result confirmed that when 220V current authorized, the temperature, electric current, electric power and the resistance rise to stationary state in early stage. Moreover, the temperatures and electric characteristics show a good stability.

• 한국컴퓨터그래픽스학회논문지
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• 제16권2호
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• pp.1-7
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• 2010

본 논문에서는 큰 회전 변형이 일어나는 가는 막대를 실시간에 시뮬레이션하는 기법을 제안한다. 가는 막대는 로프나 머리카락과 같이 일차원적인 구조를 표현하는데 널리 사용될 수 있다. 시각적으로 사실적인 가는 막대의 애니메이션을 실시간에 생성하는 것은 컴퓨터 그래픽스분야에서 오랫동안 주요한 도전 과제였다. 본 논문에서는 연속체 역학에 기반한 지배방정식을 세우고 이를 실시간에 적분하는 가는 막대구조를 위한 모달와핑기법을 개발한다. 이와같은 새로운 시뮬레이션 기법은 삼차원 솔리드를 위해 개발된 종전의 모달 와핑 기법을 확장한 것이다. 본 논문에서 제안한 방법은 매우 많은 정점으로 이루어진 가는 막대 구조의 큰 휨과 꼬임변형도 실시간에 사실적으로 생성할 수 있다.

• 한국전기전자재료학회논문지
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• 제14권9호
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• pp.731-735
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• 2001

S $r_{0.89}$B $i_{2.4}$T $a_2$ $O_{9}$ (SBT) thin films are deposited on Pt-coated electrode(Pt/Ti $O_2$/ $SiO_2$/Si) using RF magnetron sputtering method. In the XRD pattern, the SBT thin films had (105) orientation. As annealing temperature was increased from $600^{\circ}C$ to 85$0^{\circ}C$, the intensities of peak were increased. In the SEM images, Bi-layered perovskite phase was crystallized above $650^{\circ}C$ and rod-like grains grew above 75$0^{\circ}C$. The maximum remanent polarization and the coercive electric field at annealing temperature of 75$0^{\circ}C$ are 11.60$\mu$C/$\textrm{cm}^2$ and 48kV/cm respectively. The dielectric constant and leakage current density at annealing temperature of 75$0^{\circ}C$ are 213 and 1.01x10$^{-8}$ A/$\textrm{cm}^2$, respectively. The fatigue characteristics of SBT thin filmsdid not change up to 10$^{10}$ switching cycles.s.s.

• 한국기계가공학회지
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• 제15권2호
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• pp.118-124
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• 2016

In this study, experiments are conducted to improve spray coating uniformity by using second and third electrodes based on the electrospray atomization mechanism. The uniformity of fabricated thin films can be improved by adjusting the design of the second electrode. The implementation of the second electrode with an elongated hole and a bending angle of $90^{\circ}$ results in highly uniform films. In addition, induced area to substrate is increased by lowering the applied voltage using the third electrode with a round rod shape. A linear correlation between applied voltage and induced area is confirmed. Thin film thickness and surface roughness are measured after the fabrication of thin films through the electrospray process. It is confirmed that a thin film is formed having an average thickness of 273.44 nm, a thickness uniformity of less than 10%, and a surface roughness of 3 nm.

• 대한기계학회논문집B
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• 제23권3호
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• pp.311-319
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• 1999

The thermal conductivity ${\lambda}_b$, thermal diffusivity ${\alpha}_b$ of the thin black paint layer sprayed on solid surface and absorptivity a for laser beam are measured by applying a non-contact measurement method of the thermophysical properties of solids. The values of a=0.67, ${\lambda}_b=1.45W/mK$ and ${\alpha}_b=1.24{\times}10^{-6}m^2/s$ are obtained for the sprayed lay~ thickness $z_b{\fallingdotseq}40\;{\mu}m$. Furthermore, for the $z_b{\fallingdotseq}24\;{\mu}m$ thick layers which arc formed by rubbing with a glass rod after spraying, the values of a=0.73, ${\lambda}_b=1.85W/mK$. and ${\alpha}_b=1.09{\times}10^{-6}m^2/s$ are obtained. It is also shown that the present thermal diffusivity ${\alpha}_b$ for $z_b{\fallingdotseq}40\;{\mu}m$ Is about 30~80% larger than those obtained by Araki et al. for the thicker layer $z_b{\fallingdotseq}150{\sim}248\;{\mu}m$. This method could be applied to the measurement of thermophysical properties of thin layer on solids.

• 대한기계학회논문집A
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• 제25권12호
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• pp.1950-1959
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• 2001

An active control of the vibration transmitted by longitudinal load in flight control system is investigated numerically. The flight control system is modeled as a finite, thin shell cylinder with constant thickness. A vibration source is generated by exterior monopole source. Distributed piezoelectric actuator is used to control of the vibration. Thin shell theory is used to formulate the numerical models. The amplitude of vibration at discrete location and power transmission are minimized by analytical optimization method. Genetic algorithm is used as numerical optimization method to search optimal actuator position and size which amplitude of vibration is minimized.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.103.2-103.2
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• 2011

비정질 실리콘 태양전지의 효율을 증가하기 위하여 많이 사용되는 방법 중 하나는 입사되는 빛의 산란을 증가하여 태양전지의 광흡수를 증가시키는 방법이다. 이를 위하여 양극전극으로 사용되는 TCO층의 일정한 패턴 처리를 통하여 광산란을 증가시키는 방법이 사용되고 있다. 본 연구에서는 나노 임프린트 리소그래피방법을 사용하여 Ag 나노로드를 증착한 기판을 제조하고 이를 비정질 실리콘 태양전지에 적용하였다. 실험결과, 그림과 같이 높이와 너비가 300nm 정도로 일정한 패턴의 Ag 나노로드를 제조하였다. 또한, 그 위에 증착된 Si 박막의 경우, 나노로드 전체를 감싸는 돔 형태로 성장하였다. 이와 같은 나노로드 위에 substrate n-i-p 구조의 비정질 박막 태양전지를 증착하고 그 특성변화를 분석하고자 하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.822-825
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• 2003

Maxwell displacement current (MDC) measurement has been employed to study the dielectric property of Langmuir-films. A method for determining the dielectric relaxation time $\tau$ of floating monolayers on water surface is presented. WC flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$ of monolayers in the isotropic polar orientational phase is determined using a liner relationship between the monolayer compression speed ${\alpha}$ and the molecular area Am. Compression speed ${\alpha}$ was about 30, 40, 50mm/min.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.84-89
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• 2001

Ultrasonic pulse echo method comes to be difficult to apply to the multi-layered structure with very thin layer, because the echoes from the top and the bottom of the layer are overlapped. Conventionally method, deconvolution technique has been used for the decomposition of overlapped UT signals, however it has disabilities when the waveform of the transmitted signal is distorted according to the propagation. In this paper, the wavelet transform based deconvolution (WTBD) technique is proposed as a new signal processing method that can decompose the overlapped echo signals in A-Scan signal with superior performances compared to the conventional deconvolution technique. Performances of the proposed method are shown by through computer simulations using model signal with noise and are demonstrated by through experiments for the fabricated acryl rod with a thin steel plate bonded to it.