• 한국자동차공학회논문집
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• 제8권5호
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• pp.67-77
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• 2000

Investigated was the effect of propene(C3H6) on the NO-NO2 conversion in dry exhaust gases from lean burn engine using a pulsed corona discharge. A kinetic model was developed to characterize the plasma chemistry in simulated exhausts containing propene. The model uses ELENDIF program to solve Boltzmann equation for electron energy distribution function, and CHEMKIN-II program to solve stiff ODE(ordinary differential equation) problems for species concentrations. The corona discharge energy per pulse and the time-space averaged E/N were obtained by fitting the model to experimental data. The model calculation shows good agreement for NO and NO2 concentrations with the experimental data, and predicts the formation of byproducts such as CH2O, CH3HCO, CO AND CH3NO2 Propene enhances the NOx conversion enormously at lower energy density and the NOx conversion increases with the increase of initial propene and oxygen concentration, and temperature.

• 정보처리학회논문지A
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• 제18A권1호
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• pp.25-32
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• 2011

최근, 공유버스 구조의 한계를 극복하기 위하여 NoC가 활발하게 연구되고 있다. 본 논문에서는 NoC 구조의 통신 효율을 향상시키기 위해, 컴퓨터 네트워크의 프록시 서버와 유사한 역할을 하는 버퍼를 사용한 NoC 구조를 제안한다. 제안된 NoC 구조에서 매스터가 슬레이브와 직접 통신하기 어려울 때마다 매스터를 대신하여 슬레이브와 통신할 수 있는 프록시 서버와 통신한다. NoC에서 제안된 방식을 사용하면 통신 채널의 속도를 높이고 대역폭을 늘릴 수 있다. 실험 결과로부터, 패킷을 스위치 버퍼에 머무르게 하지 않고 프록시 서버에 보냄으로써 전반적인 통신효율이 크게 향상됨을 확인하였다.

• 조명전기설비학회논문지
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• 제15권1호
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• pp.98-103
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• 2001

본 연구는 전기적 방법인 선대원통형 전극구조에서 발생되는 비열플라즈마를 이용하여 반응장치내에서의 NO의 제거율을 측정하고, 또 방전시의 방전 Image와 수평방향과 수직방향의 신호강도를 ICCD카메라를 이용하여 관측하였다. NO입자의 제거율은 NO농도가 낮을수록 높아지는 것을 확인할 수 있었으며, 수평방향의 신호강도와 수직방향의 신호강도는 NO농도가 낮을수록 큰 것을 확인할 수 있었다. 특히 방전에 의해 발생되는 비열플라즈마를 이용했을때의 교류방전시의 Image를 관측함으로써 NO입자의 방전 메카니즘을 보다 명확하게 규명하고자 하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.295-296
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• 2015

We presented the methods calculating the reduction efficiency of nitrogen oxide for the low $NO_x$ burner as the pollution prevention facilities. The standard $NO_x$ concentration was used on the emission factor of LNG, $3.7g/m^3$. The $NO_x$ reduction efficiency based on the $NO_x$ concentration was presented and the relationships between the $NO_x$ concentration and the emission factor or the specific heat emission factor were derived. These results could be accurately reflected on calculating the amount of the nitrogen oxide emissions. In addition, according to the arrangement of the low $NO_x$ burners the methods of applying their $NO_x$ reduction efficiency were proposed. The $NO_x$ reduction efficiency for the facilities consisting of the low $NO_x$ burners and the non-low $NO_x$ burners could be estimated with information about the reduction efficiency of each low $NO_x$ burners, the fuel consumption rate, and the heating value of fuel.

• 대한기계학회논문집B
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• 제22권2호
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• pp.193-204
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• 1998

Numerical analysis was performed with multicomponent transport properties and detailed reaction mechanisms for axisymmetric 2-D CH$_{4}$ jet diffusion flame. Calculations were carried out twice with the $C_{2}$-Thermal Mechanism including $C_{2}$ and thermal NO reactions and the $C_{2}$-Full Mechanism including prompt NO reactions in addition to the above $C_{2}$-Thermal NO mechanism. The results show that the flame structures such as flame temperature, major and minor species concentration are indifferent to respective mechanisms. The production path of Thermal NO is dominant comparing with that of Prompt NO in total NO production of pure CH$_{4}$ jet diffusion flame. This is because thermal NO mechanism mainly contributes to positive formation of NO in the whole flame region, but Prompt NO mechanism contributes to negative formation in the fuel rich region. In addition, 0$_{2}$ penetration near the nozzle outlet affects the flame structures, especially N0$_{2}$ formation characteristics.

• 대한전자공학회논문지TC
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• 제42권1호`
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• pp.49-60
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• 2005

유무선 기간 망에서 사용되어 지는 Core Network System간 연동 부분의 Back Bone이 NO.7 Protocol이다. 그래서 유선망에서 기본적인 중계 ISUP이나, 지능망 INAP 처리, 그리고 이동망에서 각 Network Element System간 연동되는 MAP 연동 방식이 NO.7 방식을 사용하고 있다. 따라서 이 NO.7을 이용하는 Core Network에서 운영 중에 장애가 발생하거나, 기존에 인지되지 않고 지나온 문제점들을 최단시간에 감지하여 도출할 수 있는 시스템이 필요로 되었다. 본 논문에서는 Core Network 에서 사용되는 NO.7 Signaling 방식에 대해 더욱 신뢰성을 확보하고, 장애 발생 여부 등을 분석할 수 있도록 하기 위하여 NO.7 Signaling Message들을 추출하여 Core Network 시스템의 기능 및 성능을 분석하고 Report를 작성할 수 있는 NO.7 Protocol 분석 측정 시스템을 고안하였다. 이 시스템은 NO.7 Signaling을 담당하는 Core Network 시스템의 NO.7 HW Module 에 연결하여 Monitoring만 수행하고, 어떤 시나리오에 대한 Emulator 기능이나 Simulation 기능은 제공하지 않는다. 이 시스템은 현재 NO.7 MTP, ISUP, INAP, 그리고 MAP 에 대해 측정 및 분석기능을 수행하도록 하였고, 여러 유무선 기간 망 사업자에 제공하여 SW 및 HW 적인 면 그리고 운영적인면 등에서 여러 가지 문제들을 확인하여 교정할 수 있었다. 향후에는 이외에 BSC-MSC 연동되어 지는 A-Interface 등과 같은 기능도 제공함으로써 NO.7 Protocol 전반적인 분석과 동시에 Core Network 시스템에 효율적인 운영을 도모할 수 있다.

• KSBB Journal
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• 제25권1호
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• pp.62-66
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• 2010

호기 상태에서 ${NO_X}^-$-N이 PAOs에 의한 인 흡수속도에 미치는 영향을 각기 세 가지 조건의 회분식 실험을 통하여 관찰하였다. 실험 결과를 요약하면 다음과 같다. 1) 인 과잉흡수가 이루어지는 호기 상태에서 PAOs는 ${NO_X}^-$-N에 의해 인 흡수에 방해를 받는 것으로 나타났다. 2) 인 흡수속도에 있어 ${NO_3}^-$-N보다 같은 농도의 ${NO_2}^-$-N가 PAOs의 인 흡수속도를 저하시키는 결과를 나타내었다. 10 mg/L의 같은 농도로 유입되었음에도 불구하고 ${NO_2}^-$-N에 의한 인 흡수속도는 15.61 mg/gVSS로 10 mg/L의 ${NO_3}^-$-N가 공급된 실험에서의 인 흡수속도 28.30 mg/gVSS보다 낮은 속도를 나타냈다. 3) 반응기내의 ${NO_2}^-$-N 농도가 2 mg/L 이상으로 존재할 시 PAOs의 인 흡수속도는 ${NO_X}^-$-N가 존재하지 않는 조건에서 인 흡수 속도의 24%를 나타냈으며, ${NO_3}^-$-N의 농도가 3 mg/L 이상으로 존재할 경우 ${NO_X}^-$-N가 존재하지 않는 조건에서 인 흡수 속도의 17% 이하로 감소하는 것으로 나타나 ${NO_2}^-$-N가 PAOs의 인 흡수에 심각한 저해를 미치는 것으로 나타났다. 4) 반응기내에 ${NO_2}^-$-N와 ${NO_3}^-$-N가 함께 존재할 시에는 ${NO_X}^-$-N가 존재하지 않는 조건에서 인 흡수 속도의 6% 이하로 감소하는 것으로 나타났다. 5) ${NO_2}^-$-N는 EBPR의 붕괴에 영향을 미치는 중요한 요소로 판명되었다.

• ALGAE
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• 제33권1호
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• pp.101-108
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• 2018

Saccharina japonica was introduced to both Korea and China from Hokkaido, Japan, and it has become an economically important species in both nations. After a long period of cultivation, several varieties of S. japonica have been developed in Korea and China. In this study, we conducted aquacultural research on the persistence of thalli from two kelp cultivars, one from China (Huangguan No. 1) and one from Korea (Sugwawon No. 301), between December 2015 and November 2016 in Haenam, Korea. The maximum length was $247.8{\pm}13.0$ and $227.5{\pm}42.0cm$, respectively, which were significantly longer in Sugwawon No. 301 than in Huangguan No. 1. The maximum width was $29.9{\pm}5.4$ and $23.2{\pm}1.9cm$, respectively, which were significantly wider in Huangguan No. 1 than in Sugwawon No. 301. The mean biomass obtained from the culture ropes was for Sugwawon No. 301 was $3.5{\pm}0.3kg\;wet\;wt\;m^{-1}$ and for while Huangguan No. 1 was $3.1{\pm}1.0kg\;wet\;wt\;m^{-1}$ of culture rope. After August, the persistence of the thalli of Sugwawon No. 301 was two months longer than that of Huangguan No. 1. We found that the Sugwawon No. 301 performed as well as the Huangguan No. 1 in Korean waters possibly due to increased flexibility as a result of the different cell arrangements of the two cultivars. Overall, the use of the Sugwawon No. 301 cultivar rather than the Huangguan No. 1 cultivar of S. japonica appears the best alternative to help to ensure a stable year round algal feed supply for the Korean abalone industry.

• 한국자동차공학회논문집
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• 제24권3호
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• pp.345-351
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• 2016

This study was carried out to determine an optimal lean $NO_x$ trap (LNT) regeneration condition based on a $NO_x$ storage fraction. The LNT regeneration was performed by an in-cylinder post fuel injection method. A $NO_x$ storage fraction is defined by the ratio of current cumulated $NO_x$ amount in the LNT to the $NO_x$ storage capacity: 0 means empty and 1 fully loaded. In this study five engine operating conditions were chosen to represent the New European Driving Cycle. With various $NO_x$ storage fractions each engine operating condition, the LNT regeneration was executed and then $NO_x$ conversion efficiency, additional fuel consumption, CO and THC slip, peak catalyst temperature were measured. The results showed that there exist an optimal condition to regenerate the LNT, eg. 1500 rpm 6 bar BMEP with below 0.7 $NO_x$ storage fraction in this experimental constraint.

• Asian Journal of Atmospheric Environment
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• 제12권1호
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• pp.17-29
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• 2018

For the first time in the city of Riyadh, the formation of $O_3$ and its relationship with NO and $NO_2$ ($NO_x$) was investigated. Throughout the summer $O_3$, NO, and $NO_2$ were collected from three locations: residential, industrial, and rural areas. During the sampling period $O_3$ concentrations exceeded 1-hour local standards a few times yet remained consistent with the standards most of the time. The $O_3$ concentrations were observed highest in the rural location and lowest in the industrial area. The diurnal variation of NO followed a double peak: one in the morning and the other in the evening, representing the traffic pattern. Early morning NO peaks were observed in the rural location, which were attributed to the movement of NO from other locations. The $O_3$ concentrations depicted typical pattern, increasing after sunrise and reaching its maximum during midday. The highest $O_3$ concentrations were observed in the rural location followed by the residential and industrial. $NO_2$ photolysis rates were 3-4 times higher compared to other similar investigations, potentially due to intense solar radiation. A strong negative correlation was observed between $NO_x$ and $O_3$ values in the industrial location indicating photochemical activities around the industrial area were higher, likely due to additional $NO_x$ emissions from industries. Regression analysis of $NO_x$ and OX ($O_3+NO_2$) indicated that in residential and industrial locations at nighttime there were large $NO_x$ independent regional contributions which is attributed to VOCs. The Weekend Effect was observed in the city potentially due to the production of the OH radical and subsequent reactions with VOCs implying that the area is VOC-sensitive.