• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.343-346
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• 1998

Ultra-thin gate oxide in MOS devices are subjected to high-field stress during device operation, which degrades the oxide and exentually causes dielectric breakdown. In this paper, we investigate the electrical properties of ultra-thin nitrided oxide (NO) and reoxidized nitrided oxide(ONO) films that are considered to be promising candidates for replacing conventional silicon dioxide film in ULSI level integration. We study vriations of I-V characteristics due to F-N tunneling, and time-dependent dielectric breakdown (TDDB) of thin layer NO and ONO depending on nitridation and reoxidation condition, and compare with thermal $SiO_{2}$. From the measurement results, we find that these NO and ONO thin films are strongly depending on its condition and that optimized reoxided nitrided oxides (ONO) films show superior dielectric characteristics, and breakdown-to-change ( $Q_{bd}$ ) performance over the NO films, while maintaining a similar electric field dependence compared to NO layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.79-82
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• 1994

We have manufacture Copper-tetra-tert-butylphalocyanine (CuTBP)Langmuir-Blodgett(LB) films, which is known be sensitive to NO$_2$ gab. A response of these films to the NO$_2$ gab was studied. A surface pleasure of 25mN/m was obtained as a proper one for a film deposition. A deposited film status was identified with Uv/visible absorption spectra, ellipsometry measurements, and current-voltage(I-Y) characteristics. The NO$_2$ gas response experiments under 200ppm conducentration show that there are increment of electrical conductivity by 12 times, 5 seconds of response time, and 5 seconds of response time, and 90 seconds of recovery time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.586-591
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• 2004

We studied the dependence of hot-tarrier-induced degradation characteristics on nitrogen concentration in NO(Nitrided-Oxide) gate of nMOS, under ac and dc stresses. The $\Delta$V$_{t}$ and $\Delta$G$_{m}$ dependence of nitrogen concentration were observed, We observed that device degradation was suppressed significantly when the nitrogen concentration in the gate was increased. Compared to $N_2$O oxynitride, NO oxynitride gate devices show a smaller sensitivity to ac stress frequency. Results suggest that the improved at-hot carrier immunity of the device with NO gate may be due to the significantly suppressed interface state generation and neutral trap generation during stress.ess.

• Journal of Advanced Marine Engineering and Technology
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• v.26 no.6
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• pp.679-687
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• 2002

In this study, a cycle simulation using a two-zone model is carried out to investigate the effect of intake charging conditions such as oxygen concentration, temperature and pressure on NO emissions in a DI diesel engine. The model is validated against measurements in terms of cylinder pressure, torque, BSFC and NOx emissions with 2902 cc DI diesel engine. Calculated results can be summarized as follows. The oxygen concentration in the intake charge is decreased with increasing of EGR rate and equivalence ratio. As the intake oxygen concentration is reduced, the combustion pressure and the burned gas temperature decrease and, as a result, NO formation decreases. Also, the results show that as the intake pressure increases and the intake temperature decreases, NO emissions are effectively reduced.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.4
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• pp.117-123
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• 2008

In this paper, we propose a novel ant colony optimization(ACO)-based application core ma ins method for implementing network-on-chip(NoC)-based systems-on-chip(SoCs). The proposed method efficiently put application cores to a mesh-type NoC satisfying a given design objective, the network latency. Experimental results using a functional circuit including 12 cores show that the proposed algorithm can produce near optimal mapping results within a second.

• ETRI Journal
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• v.28 no.4
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• pp.475-485
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• 2006

Network-on-chip (NoC) is an emerging design paradigm intended to cope with future systems-on-chips (SoCs) containing numerous built-in cores. Since NoCs have some outstanding features regarding design complexity, timing, scalability, power dissipation and so on, widespread interest in this novel paradigm is likely to grow. The test strategy is a significant factor in the practicality and feasibility of NoC-based SoCs. Among the existing test issues for NoC-based SoCs, test access mechanism architecture and test scheduling particularly dominate the overall test performance. In this paper, we propose an efficient NoC-based SoC test scheduling algorithm based on a rectangle packing approach used for current SoC tests. In order to adopt the rectangle packing solution, we designed specific methods and configurations for testing NoC-based SoCs, such as test packet routing, test pattern generation, and absorption. Furthermore, we extended and improved the proposed algorithm using multiple test clocks. Experimental results using some ITC'02 benchmark circuits show that the proposed algorithm can reduce the overall test time by up to 55%, and 20% on average compared with previous works. In addition, the computation time of the algorithm is less than one second in most cases. Consequently, we expect the proposed scheduling algorithm to be a promising and competitive method for testing NoC-based SoCs.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1499-1504
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• 2004

Flue gas recirculation (FGR) is a method used to control oxides of nitrogen ($NO_x$) in combustion system. The recirculated flue gases resulted in slow reaction and low flame temperatures, which in turn resulted in decreased thermal NO production. Recently, it has been demonstrated that introducing the recirculated flue gas in the fuel stream, that is, the fuel induced recirculation (FIR), resulted in a much greater reduction in $NO_x$ per unit mass of recirculated gas, as compared to introducing the flue gases in air. In the present study, the effect on $NO_x$ reduction in turbulent swirl flame in laboratory scale using FGR/FIR methods through the dilution using $N_2$ and $CO_2$. Results. show the $CO_2$ dilution is more effective $NO_x$ reduction methods because of large temperature drop due to the larger specific heat $CO_2$ compared to $N_2$. FIR is more effective to reduce $NO_x$ emission than FGR when the same recirculation ratio of dilution gas.

• Nuclear Engineering and Technology
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• v.54 no.2
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• pp.486-492
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• 2022

Nitrogen oxides (NO_x; NO and NO₂) are major air pollutants and can cause harmful effects on the human body. Electron Beam Flue Gas Treatment (EBFGT) is a technology that generates electrons with an energy of 0.5-1 MeV using electron accelerators and effectively processes exhaust gases. In this study, NO_x was removed using an electron beam accelerator with spraying additives (NaOH and NH₄OH). NO and NO₂ were 100% and more than 94% removed, respectively, at an electron beam absorbed dose of 20 kGy and an additive concentration of 0.02 M (mol/L). In most cases, NO_x was removed better with lower initial NOx concentrations and higher electron beam absorbed doses. As the irradiation strength (mA) of the electron beam increases, the probability of electron impact on the material accordingly rises, which may lead to increase removal efficiency. The results of the present study show that the continuous electron beam process using additives achieved more effective removal efficiency than either individual process (wet-scrubbing or EB irradiation only).

• Journal of the Chungcheong Mathematical Society
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• v.20 no.4
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• pp.457-463
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• 2007

We show that any filter of Tarski algebra can be de-composed into the union of some sets. Moreover, we introduce the notion of expansions of filters in Tarski algebras, and discuss the notion of ${\sigma}$-primary filters in Tarski algebras. Finally, we show that there is no non-trivial quadratic Tarski algebras on a field X with $|X|{\geq}3$.

• Journal of the Korean Statistical Society
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• v.35 no.3
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• pp.225-238
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• 2006

This paper considers noninformative priors for the scale parameter of exponential distribution when the data are collected in step stress accelerated life tests. We find the Jeffreys' and reference priors for this model and show that the reference prior satisfies first order matching criterion. Also, we show that there exists no second order matching prior in this problem. Some simulation results are given and we perform Bayesian analysis for proposed priors using some data.