• 기술혁신연구
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• 제25권2호
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• pp.127-152
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• 2017

1995년 WTO 체제가 출범한 이후 전통적인 무역장벽 이외에 기술규정, 표준 및 적합성평가절차 등과 같은 비관세 기술장벽이 국가 간 교역의 중요한 이슈로 대두되었다. 본 연구는 무역기술장벽의 제거에 필요한 기술기반을 마련하기 위하여 국가측정표준기관(NMIs) 간에 체결된 국제도량형위원회 상호인정협정(CIPM MRA)의 이행이 한국의 교역에 어떠한 영향을 미치는지에 대하여 분석하였다. 국가측정표준의 동등성에 관한 자료인 CMC를 대용변수(proxy)로 중력모형을 활용하여 실증분석한 결과, CMC는 한국의 교역에 긍정적인 영향을 미치는 것으로 나타났다. 특히, 소득이 높은 국가의 CMC가 낮은 국가에 비하여 더 큰 영향을 주는 것으로 나타났다. 이러한 결과는 우리나라와 같이 무역의존도가 높은 국가의 경우, 공공재로 인식되고 있는 국가측정표준의 확립과 향상을 위하여 지속적인 자원투입을 하는 것이 경제성장에 중요한 역할을 할 수 있다는 점을 시사한다.

• 한국산업융합학회 논문집
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• 제9권1호
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• pp.21-27
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• 2006

The laminar burning velocity was measured using a spherical combustion bomb with central ignition. Mixtures with equivalence ratio between 0.6 and 1.2, were tested. The computation was carried out for the burning velocity using premix code of Chemkin program under the unburned gas pressure of 0.5bar-30bar and temperature of 300K-700K at ${\Phi}1.0$. The results showed little difference between these two methods. The burning velocity was decreased by increasing the pressure and increased by increasing the temperature. The burning velocity was predicted by using the following equations $$S_L(m/s) = S_{st}(T/300)^{1.85}(P)^{-0.45}$$ $$(0.5bar{\leq}P{\leq}30bar,\;300K{\leq}T{\leq}700K)$$).

• 동력기계공학회지
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• 제2권2호
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• pp.13-19
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• 1998

The purpose of study is to investigate the flame stability and Structure of turbulent diffusion flame behind the hollowed flame holder, which is located on the waste gas coming out from the test furnace. Fluctuating temperature and ion current measurement and their statistical treatment were used for the purpose. Three types of flame were stabilized and each of which were changed by adequate equivalence ration. And we found that have no periodicity near reacting zone.

• 한국환경과학회지
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• 제29권8호
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• pp.847-855
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• 2020

This study presented problems and improvements in the quality control of an air monitoring network, using Gyeongnam as an example. 1) The effective utilization rate of the air monitoring was 95%, which showed good management, but the maximum of 2% was indicated by zero or detection limit among measurement data. 2) In the equivalence evaluation of PM_2.5, the slope and intercept satisfy the evaluation criteria; however, 1% of the PM_2.5/PM₁₀ ratios were outliers. 3) All air monitoring stations meet the quality control standards; however, the management status is added to the quality inspection, management system is unified and the related budget is expanded, and systematic commission management is required.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1372-1377
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• 2003

The stabilization of propane/air lean premixed flames by a heated cylindrical rod is investigated experimentally. The flame stability limits, heat flux, surface temperatures, equivalence ratios, and mixture velocities are measured in order to understand the role of heat flux or surface temperature on the flame stabilization of lean premixed flames. The flame stability limits are lowered by a heated cylindrical rod and extended even below the flammability limit of propane/air mixture when sufficient heat flux is provided. The flame stability limit decreases with the increase of heat flux or surface temperature and decreases with the higher mixture velocity. The diameter of cylindrical rod, however, dose not significantly affect the flame stability limit. The laminar flame speed has been measured for ultra lean propane/air premixed flames. The flame stabilization by a heated cylindrical rod provides the useful tool for the measurement of flame speed under very fuel-lean conditions.

• 한국자동차공학회논문집
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• 제10권2호
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• pp.73-79
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• 2002

The NO emissions at the exhaust manifo1d were investigated with a fast NO analyzer to investigate the cycle-by-cycle variations on NO emissions level and the dependence of NO emissions on combustion. The measurement was performed with a part load condition with respect to the mixture ratios and the changes in loads at 1800rpm. The averaged values were obtained during 200 cycles. We found that there is characteristic pattern in 70 emissions from exhaust port and it was possible to set a representative value with the data sampled during specific period. As the load increased, the characteristics of NO emissions were more dependent on combustion pressures. It was also analyzed that the correlation between combustion pressures and NO emissions for different equivalence ratios tends to increase as the mixture goes leaner, Furthermore, this correlation for the lean mixture near the lean limit seemed to be kept.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.677-680
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• 2009

DC influence between pixel electrode and alignment layer (AL) in in-plane switching mode LCD was analyzed through DC equivalence-circuit equation induction, DC charge-discharge simulation, luminance and residual-DC measurement systems using test patterned (TP) cell. DC discharging rate (DDR) of single layer electrode was faster than that of double layer electrode and DDR of low resistance AL was faster than that of high resistance AL. DC discharging characteristics had a close relation to layer number and resistance between two electrodes.

• 한국연소학회지
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• 제19권1호
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• pp.11-16
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• 2014

Spherically expanding flames are used to measure flame speeds, which are derived the corresponding laminar flame speeds at zero stretch. Dimethyl Ether-Air mixtures at high pressure are studied over an extensive range of equivalence ratios. The classical shadowgraph technique is used to detect the reaction zone. In analytical methodology the optimization process using least mean squares is performed to extract the laminar flame speeds. It is seen that the laminar flame speed of DME-Air mixture with the increase of pressure decreases rapidly showing a similar trend to other hydrocarbon fuels. At pressure of 2 and 10 atm the experimental data from the present study agree well with results reported in the literature. Especially the laminar flame speeds at 2 atm are in good agreement with those calculated in numerical work over the full stoichiometric range. At elevated pressure of 12 atm the measured data are slightly slower at fuel lean condition and show close agreement at fuel rich condition when compared with the numerical results.

• 한국컴퓨터정보학회논문지
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• 제24권2호
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• pp.57-66
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• 2019

This paper compared the performance with an overview of channel equalization techniques used in high-speed serial transceivers, including the homogeneous architecture and associated components for the GHz interconnect of backplane and cable channels. It also used the MATLAB tool to present system analysis and simulation results for continuous time equivalent structures. In the case of conventional continuous equalization, high frequency deficits occur due to the use of a comparator that is difficult to implement as well as the low speed limit. In this paper, the channel equalization technique based on the power spectrum analysis of clocks was used to compensate for the frequency loss, and the application of the TX+Channel and TX+Equalizer filters enabled the measurement of attenuation and equivalence without comparators. The application of blender and band-pass filters at high speeds also showed significant effectiveness.

• 한국수소및신에너지학회논문집
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• 제30권1호
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• pp.67-75
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• 2019

An experimental study was conducted to measure laminar burning velocity and Markstein length of SNG fuel with 3% of hydrogen contents from spherical propagating flames at normal and elevated initial pressure. These results were compared with numerical calculations by Premix code with GRI-mech 3.0, USC II and UC San Diego to provide suitable mechanism for SNG fuel. As a result of this work, it was found that the burning velocities and Markstein lengths of SNG fuel decrease with increase of initial pressure regardless of equivalence ratio. In addition, numerical calculations with GRI-mech 3.0 were coincided with experimental results.