• 한국작물학회지
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• 제57권1호
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• pp.89-97
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• 2012

1. 30년 장기 연용구의 연작 대비 윤작에 의한 옥수수 및 콩의 수량증대는 옥수수보다 콩이 더 컸으며, 연작시 무경운에 따라 수량이 감소되었던 옥수수는 윤작에 의해 수량이 많이 회복되었다. 콩은 연 윤작구 모두 무경운에서도 수량이 감소하지 않았다. 2. 윤작구의 작물재배기간의 이산화탄소 누적발생량은 재배작물 및 처리간 차이가 없었으며, 메탄은 콩의 재배시 plow 경운구에서 생육초기에 증가하였다. 3. 아산화질소의 발생은 옥수수 생육초기 질소시비 후에 질소비료의 무기화 과정에서 발생량이 증가하였는데, 경운방법에 따라 차이가 뚜렷하여 chisel 경운에서 가장 높았고, 무경운에서 가장 낮았다. 4. 콩-옥수수 윤작체계에서 plow 및 chisel 경운에 비해 무경운(no-tillage)의 채택에 따라 작물의 수량 감소없이 콩 재배 시 메탄 $0.7kg\;C\;ha^{-1}$ 및 옥수수 재배 시 아산화질소 $2{\sim}4kg\;N\;ha^{-1}$ 발생량을 감소시킬 수 있었다.

• E2M - 전기 전자와 첨단 소재
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• 제15권12호
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• pp.11-18
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• 2002

전계 방출 디스플레이(Field Emission Display : FED)는 금속 또는 반도체로 만들어진 극미세 구조의 전계 에미터(field emitter)에 전기장을 인가하여 진공 속으로 방출되는 전자를 형광체에 충돌시켜 화상을 표시하는 디스플레이 소자로서, 원리적으로 브라운관(CRT)의 우수한 표시 특성을 그대로 가지면서 경량 박형화가 가능하기 때문에 'Thin CRT'라고 불리기도 한다 FED는 원리적으로 고휘도, 저소비전력, 빠른 응답속도, 광시야각, 고해상도, 우수한 칼라 표시. 넓은 사용온도 범위 등 CRT 및 평판 디스플레이의 장점을 모두 갖추고 있는 이상적인 디스플레이 소자로 평가되어 1990년대 초반부터 세계 유수의 연구 기관들이 본격 적 인 연구 개발을 추진하여 왔지만, 아직까지 평판 디스플레이 시장에 진입 할 만큼 기술 개발이 이루어지지 못하고 있다. 본 고에서는 FED의 근간이 되는 전계방출 소자의 원리 및 종류, FED의 핵심요소 기술, 최근 연구 개발 동향, FED의 응용 분야 및 상용화 가능성 등에 대하여 살펴보기로 한다.

• Journal of Electrical Engineering and Technology
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• 제2권3호
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• pp.306-311
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• 2007

The transient fields generated during switching operations in a Gas Insulated Substation (GIS) are associated with high frequency components in the order of few tens of MHz. These transient fields leak into the external environment of the gas-insulated equipment and can interfere with the nearby electronics. Measurements of the transient fields are thus required to characterise the interference caused by switching phenomena in such substations. In view of the above, E-field emission measurement during a switching operation has been carried out for a 245 kV GIS model, using a resonant dipole antenna and D-dot sensor. The characteristics of the E-fields i.e., frequency spectra and their levels have been analysed and are reported in the paper. Suitability of the measurements has been confirmed by comparing frequency spectra of the measured and computed transient fields.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제50권10호
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• pp.532-535
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• 2001

The sputtering condition of Cr thin film was established in order to get Cr gate electrode having a vertical wall structure for Mo-tip FEA. In case of Mo-tip FEA which had a vertically-etched Cr gate electrode, the field enhancement factor, was relatively increased and so the field emission performance in terms of turn-on voltage, emission current and trans-conductance could be improved when compared with the devices having a tapered gate wall.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1347_1348
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• 2009

We fabricated FEDs based on ZnO nanowires. ZnO nanowires were synthesized on Au thin films by hydrothermal method on hot plate. After 2 hours, we obtained nanowires of chin form. The high-purity nanowires showed sharp tips geometry with a wurtzite structure. The field emission properties of the ZnO nanowires were investigated in high vacuum chamber. The turn-on field for the ZnO nanowires was found to be about 4.1 V/${\mu}m$ at a current density of $0.1{\mu}A/cm^2$.

• 한국전기전자재료학회논문지
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• 제19권4호
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• pp.367-372
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• 2006

A carbon nanotube field emission display(CNT FED) panel with a 2 inch diagonal size was fabricated using a screen printing of a prepared photo-sensitive CNT paste and vacuum in-line sealing technology. After a surface treatment of the patterned CNT, only the carbon nanotube tips are uniformly exposed on the surface. The diameter of the exposed CNTs are usually about 20 nm. Using the photo-sensitive CNT paste, we have developed a triode type CNT FEA with a self-aligned gate-emitter structure. The turn on voltage was around 100 V which corresponds to according the turn on field of about $40V/{\mu}m$. By the creation of a self-aligned gate-emitter structure, it is expected that the screen printed photo-sensitive CNT paste is promising as a good candidate for the large size field emission display.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1003-1007
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• 2005

We demonstrate color video displays driven by carbon nanotube electron field emitters. These nanotubes are incorporated into the device by selective growth using low temperature chemical vapor deposition. The device structure is simple and inexpensive to fabricate, and a 45 V switching voltage enables the use of low cost driver electronics. The prototype units are sealed 4.6” diagonal displays with 726 um pixels. They represent a piece of a 42” diagonal 1280x720 high definition television. The carbon nanotube growth process is performed as the last processing step and creates nanotubes ready for field emission. No activation post-processing steps are required, so chemical and particulate contamination is not introduced. Control of the nanotube dimension, orientation, and spatial distribution during growth enables uniform, highquality, color video performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1318-1320
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• 1998

We have investigated the electrical characteristics of a MOSFET-structured silicon field emitter by employing Maxwell 2D and Silvaco simulators. The potential distribution is obtained by Maxwell 2D simulator and the field emission current is calculated by Fowler-Nordheim equations. The characteristics of MOSFET is simulated by Silvaco simulator. Simulated results are almost identical to the experimental results. Also, we have studied the emission characteristics as funtions of several geometric parameters.

• 천문학회보
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• 제37권1호
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• pp.67.1-67.1
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• 2012

Shocks are evolved when the relativistic jets in active galactic nuclei (AGNs), black hole binaries, supernova remnants (SNR) and gamma-ray bursts (GRBs) interact with the surrounding medium. The high energy particles are believed to be accelerated by the diffusive shock acceleration and the strong magnetic field is generated by Weibel instability in the shock. When ultrarelativistic electrons with strong magnetic field cool by the synchrotron emission, the radiation is observed in gamma-ray burst and the near-equipartitioned magnetic field in the external shock delays the afterglow emission. In this paper, we performed the 3D particle-in-cell (PIC) simulations to understand the characteristics of these relativistic shock and particle acceleration. Forward and reverse shocks are shaped while the unmagnetized injecting jet interacts with the unmagnetized ambient medium. Both upstream and downstream become thermalized and the particle accelerations are shown in each transition region of the shock structures.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.23-23
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• 1998

High resolution field emission dispplay(FED) devices of 5 inch diagonal in size are fully developped for the applications of near-future flat ppanel dispplays. Under the unique gate-switching drive scheme electron trajectory pprofiles are simulated and tested by considering leakage effects of each ppixel. Uniquely-pprinted sppacer with high asppect ratio are fabricated on real ITO glass for high vacuum ppackaging. In addition new gas aging scheme of stabilizing field emitting array are extensively investigated during the sealing and exhausting pprocess in order to pprevent oxidation effects on the micro tipp. Finally fulll color images of 64 gray scale will be demonstrated.