• 세라미스트
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• 제2권6호
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• pp.11-17
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• 1999

• 인포메이션 디스플레이
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• 제2권3호
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• pp.6-16
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• 2001

• 조명전기설비학회논문지
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• 제24권2호
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• pp.101-105
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• 2010

본 논문은 수열합성법에 의해 합성된 ZnO 나노와이어의 전계방출 특성을 연구하였다. ZnO 나노와이어는 핫플레이트 위에서 90[$^{\circ}C$]의 온도로 Au 박막위에서 합성되었으며, ZnO 나노와이어의 팁을 형성하기 위한 캡핑 재료로 SDS(Sodium Dodecyl Sulfate)를 0.05~0.3[wt%] 용액에 혼합하였다. 2시간동안 수열합성후 체인 형태의 ZnO 나노와이어가 성장되었다. 고순도의 ZnO 나노와이어는 울자이트(Wurzite) 구조의 팁 형태를 보였으며, ZnO 나노와이어의 전계방출 특성은 고진공 챔버에서 측정하였고, 나노와이어의 턴-온 전계는 0.1[${\mu}A/cm^2$]의 전류밀도에서 4.1V/${\mu}m$]를 나타내었다.

• 한국진공학회지
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• 제12권1호
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• pp.35-39
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• 2003

본 논문에서는 혼합가스 없이 메탄가스만을 사용하여 RF PECVD 방법으로 성장시킨 a-C 박막의 전계전자방출특성을 조사하였다. 또한 본 논문은 박막의 표면형태와 결정들의 결합구조가 어떻게 전계전자방출에 영향을 미치는가에 관하여 보고된다, a-C 박막의 전계전자방출특성은 증착온도에 크게 의존함이 확인되었다. 실온에서 성장된 카본박막의 문턱전압은 20 V/$\mu\textrm{m}$이었다. 그러나 증착온도가 $500^{\circ}C$로부터 $600^{\circ}C$로 증가함에 따라 문턱전압은 17 V/$\mu\textrm{m}$에서 10 V/$\mu\textrm{m}$으로 감소하였으며 $800^{\circ}C$에서는 문턱전압이 B V/$\mu\textrm{m}$로 크게 개선되었다. 박막의 표면형태, 구조적인 특징과 전계전자방출특성의 관계를 조사하기 위해서 라만 스펙트럼과 주사형전자현미경 (scanning electron microscopy : SEM)을 사용하였다. 박막의 물리적, 화학적, 특성은 증착온도에 매우 의존하며 이들 특성들은 전계전자방출특성에 큰 영향을 미친다는 사실을 발견했다.

• 한국재료학회지
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• 제9권10호
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• pp.1032-1036
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• 1999

Pb($\textrm{Zr}_{0.5}\textrm{Ti}_{0.5}$)$\textrm{O}_3$ 강유전체의 상부 전극 크기를 변화시키며 펄스 전기장에 의한 전자 방출 특성 및 열화에 대하여 연구하였다. 상부 전극 크기 감소에 따라 상부 전극 모서리 부근에서 분극 반전에 기여하는 강유전체 분율이 증가되어 분극이 높아졌으며, ANSYS 5.3에 의한 전기장 시뮬레이션을 통하여 비대칭 전극 구조에서의 상부 전극 모서리 부근의 전기장이 증가한다는 것을 알 수 있었다. 분극 증가에 기여하는 상부 전극 모서리 주변의 강유전체의 부피 및 전극크기당 전자 방출량은 상부 전극 크기에 무관하였다. 전자 방출 횟수에 따라 상부 전극이 침식되어 분극 및 유전 상수는 감소하였으나 전극 복구에 의해 재생되었으며, 강유전체의 표면 손상에 의해 항전계 및 유전 손실은 증가되었다.

• 한국기후변화학회지
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• 제8권4호
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• pp.305-312
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• 2017

We aimed at investigating the difference in $N_2O$ emission factors of chemical and organic fertilizers and identifying the main factors influencing annual fluctuations in $N_2O$ emission. We conducted two-year experiments in 2016 and 2017 in an agricultural field planted with sweet potato (Ipomoea batatas). Treatments included chemical NPK fertilizer (NPK) and chicken compost application at $10\;ton\;ha^{-1}$, $20\;ton\;ha^{-1}$, and $30\;ton\;ha^{-1}$ rates (CK1, CK2 and CK3). Control was also employed with no addition. Results showed that $N_2O$ emission rates were significantly related with soil water status and soil available N contents. Significant correlation between % water filled pore space (WFPS) and $N_2O$ emission was observed only when the %WFPS was greater than 40% and during the initial stage of the experiment (<60 d). Comparison of the emission factors in 2016 and 2017 showed us that the emission factor was greater in 2016 when the %WFPS was maintained higher by 16.5% compared to that in 2017. In 2016, the emission factor of organic fertilizer was higher than that of chemical fertilizer, while in 2017, the pattern was reversed. Annual variability in $N_2O$ emission could also be originated from the available N contents remaining in soil after being taken up by plants. If we apply excessive N fertilizer, the soil would contain excess amount of N which was not uptaken by plants, leading to a huge increase in $N_2O$ emission. This case would overestimate emission factor, which was the case for the organic fertilizer in 2016. Over-fertilization should be avoided when we set up an experiment to determine $N_2O$ emission factor.

• 환경영향평가
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• 제9권4호
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• pp.257-269
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• 2000

This study is to investigate the methodology and applicability on emission control by both MECHANICAL Model and Fugitive Dust Model (FDM) through the comparison of field measurement data and calculated data. Comparing to the method of AP-42 emission fector on the production of flying dust the MECHANICAL Model was proved to be more applicable to the calculation emission rate on the various dust emission conditions on a unpaved road. The seperate calculation on annual mean emission amount and a 24working hours amount was undertaken for the easy management of fugitive dust. Dust concentration predicted by FDM is similar with a measurement value.

• 천문학회보
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• 제42권2호
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• pp.81.2-81.2
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• 2017

Polarized mid-infrared emission from polycyclic aromatic hydrocarbons (PAHs) can provide a crucial test of basic physics of alignment of nanoparticles and opens a potential new window into studying magnetic fields. In this talk, I will present a new model of polarized PAH emission that takes into account the effect of PAH alignment with the magnetic field due to resonance paramagnetic relaxation. I will then present our predictions for the polarization level of the strong PAH emission features from the interstellar medium. I will present the first detection of polarization of PAH emission at 11.3micron which is consistent with our theoretical prediction. Finally, I will discuss important implications of this work for tracing magnetic fields via mid-IR PAH features and for constraining the polarization of anomalous microwave emission that is useful for the quest of CMB B-modes.

• 한국환경과학회지
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• 제20권3호
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• pp.301-308
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• 2011

The temporal variations of methene emission and its relation to air temperature were investigated in Upo-swamp during June 2007 through July 2008. To perform this study, the methene emission and air temperature were observed using the buoy-type chamber and automatic weather observation system(AWS), respectively. The methene emissions were much during summertime(June~August). The maximum value(about 73.4 mg/$m^2$/hr) appeared at August. The emission diminished by degrees after August. The methene emissions were fewer from September to May of the following year. The peak value(73.4 mg/$m^2$/hr) of the methene emission is very much compared to that of rice pappy field known as about 28.7 mg/$m^2$/hr.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.86-87
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• 2021

As non-road mobile pollutants such as construction equipment are emerging as the main cause of air pollutants emission, construction equipment regulations are gradually strengthening. Research was conducted by correcting the emission coefficient to calculate and predict air pollutant emissions of construction equipment, but it did not reflect site variables such as field and equipment conditions that affect actual emissions. This study derived an Artificial Neural Network emission prediction model based on the actual emission data of excavators and trucks measured at the site and proposed a platform to predict the emission of air pollutants at the site according to the working size and conditions. Through this, it is possible to establish an eco-friendly process plan using a model from the construction plan.