• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.888-891
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• 1996

The objective of a mixed H$_{2}$/H$_{\infty}$ controller of active suspension system is to achieve not only the general performance improvement(H$_{2}$) but also the worst case disturbance rejection(H$_{\infty}$). In this paper, a mixed H$_{2}$/H$_{\infty}$ controller for an active suspension system, comparing the performance with that of an H$_{2}$ controller and of an H$_{\infty}$ controller.ler.EX> controller.

• International Journal of Control, Automation, and Systems
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• v.1 no.2
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• pp.206-209
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• 2003

An $H_2$/$H_{\infty}$ -controller realization is carried out by considering an entropy integral. Using J-spectral factorization, the parametrizations of all $H_{\infty}$ stabilizing controllers are derived. By the relation of a mixed $H_2$/$H_{\infty}$ control problem and a minimum entropy/$H_{\infty}$ control problem, the mixed $H_2$/$H_{\infty}$-controller state-space realization is presented.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.131-142
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• 2002

The Langmuir adsorption isotherms of the under-potentially deposited hydrogen (UPD H) and the over-potentially deposited hydrogen (OPD H) at the poly-Pt/0.5M $H_2SO_4$ and 0.5 M LiOH aqueous electrolyte interfaces have been studied using cyclic voltammetric and ac impedance techniques. The behavior of the phase shift $(0^{\circ}{\leq}{-\phi}{\leq}90^{\circ})$ for the optimum intermediate frequency corresponds well to that of the fractional surface coverage $(1{\geq}{\theta}{\geq}0)$ at the interfaces. The phase-shift method, i.e., the phase-shift profile $({-\phi}\;vs.\;E)$ for the optimum intermediate frequency, can be used as a new electrochemical method to determine the Langmuir adsorption isotherms $({\theta}\;vs.\;E)$ of the UPD H and the OPD H for the cathodic $H_2$ evolution reactions at the interfaces. At the poly-Pt/0.5M $H_2SO_4$ aqueous electrolyte interface, the equilibrium constant (K) and the standard free energy $({\Delta}G_{ads})$ of the OPD H are $2.1\times10^{-4}$ and 21.0kJ/mol, respectively. At the poly-Pt/0.5M LiOH aqueous electrolyte interface, K transits from 2.7(UPD H) to $6.2\times10^{-6}$ (OPD H) depending on the cathode potential (E) and vice versa. Similarly, ${\Delta}G_{ads}$ transits from -2.5kJ/mol (UPD H) to 29.7kJ/mol (OPD H) depending on I and vice versa. The transition of K and ${\Delta}G_{ads}$ is attributed to the two distinct adsorption sites of the UPD H and the OPD H on the poly-Pt surface. The UPD H and the OPD H on the poly-Pt surface are the independent processes depending on the H adsorption sites themselves rather than the sequential processes for the cathodic $H_2$ evolution reactions. The criterion of the UPD H and the OPD H is the H adsorption sites and processes rather than the $H_2$ evolution reactions and potentials. The poly-Pt wire electrode is more efficient and useful than the Pt(100) disc electrode for the cathodic $H_2$ evolution reactions in the aqueous electrolytes. The phase-shift method is well complementary to the thermodynamic method rather than conflicting.

• Korean Journal of Animal Reproduction
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• v.15 no.2
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• pp.149-155
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• 1991

본 실험은 H-Y 항원 유전자 크로닝을 위한 기초연구로서 H-Y 항원의 특성을 규명하기 위하여 친화성 크로마토그래피에 의하여 H-Y 항원을 분리·정제하였다. 정소 추출액을 항체가 결합된 column에 결합시킨 뒤 10% acetic acid로 용출시켰다. 용출된 분획을 모아 농축한 후 HPLC와 SDS-PAGE를 실시하여 H-Y 항원의 분자량은 약 6,7000달톤 임을 알 수 있었으며 isoelectric focusing에 의하여 등전점(pI)은 5.0인 것으로 측정되었다. H-Y 항원에 대한 단일클론항체와 표지항원으로는 H-Y 항원-ABEI(aminobutylethyl isoluminol)를 사용하여 H-Y 항원 정량을 위한 화학발광면역분석법을 개발하였다. 항원항체 반응후 빛의 측정은 NaOH 존재하에서 microperoxidase/H2O2를 이용한 산화반응으로 실시하여 10초간 측정한 빛의 양을 적분하였다. H-Y 항원의 농도와 빛의 양과는 역비례하였으며 감도는 11.8ng/tube 정도이었다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.4
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• pp.875-885
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• 1999

This paper presents an application of LMI-based techniques to the mixed $H_2/ H_\infty$ control of an inverted pendulum. The linear model of the inverted pendulum represented by an LFR(Linear Fractional Representation) model of uncertainties is derived. Considered uncertainties are three nonlinear components and a parameter uncertainty Augmenting the LFR model by adding weighting functions, we get a generalized plant, for which we design a mixed $H_2/ H_\infty$ controller using the LMI technique. To evaluate control performances and robust stability of the mixed $H_2/ H_\infty$ controller designed, we compare it with the $ H_\infty$controller through the simulation and experiment. The mixed $H_2/ H_\infty$ controller shows the better control performances and robust stability than the $H_\infty$controller in the sense of pendulum angle.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.479-479
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• 2018

하천의 수심, 유속, 하상경사, 하상재료, 만곡도 등과 같은 물리적 특성에 따라 생물서식처로서 다양한 특성을 나타내고 그 특성들에 의해 서식처의 유형을 구분할 수 있다. 이러한 서식처 유형에 따라 수중음향의 특성이 달라지며, 수중음향의 서식지의 양적 표시자로서 잠재력으로 인해 최근 많은 연구들이 시도되고 있다. 본 연구에서는 인공적인 영향을 적게 받은 자연하천으로 양양 남대천 12개 지점을 대상으로 하여 서식지의 형태에 따른 수중음향과 하천의 수리적 인자에 따른 관계를 파악하고자 하였다. 서식처 유형으로는 빠른 유속에 얕은 수심을 가지고 있는 여울(riffle), 수심이 깊고 유속이 느린 소(pool), 낙차가 있는 계단형 여울(step riffle)에 대해 조사하였다. 수중배경음은 여울과 계단형 여울이 유사하게 나타났으며 소는 상대적으로 낮은 배경음을 나타내었다. H2, H4, H5, H9, H10 지점은 여울 형태로 유속에 따라 H2, H5, H4, H9 지점 순으로 음압레벨이 낮아지는 경향을 보였으며, H10지점은 H9, H4 지점에 비해 낮은 유속임에도 높은 음압레벨을 보였다. 이는 H10 지점의 하상이 조도가 매우 큰 전석으로 이루어져 나타나는 현상으로 판단된다. H3, H6, H7, H8, H12 지점은 소 형태로 H12 지점을 제외하고 대체로 낮은 음압레벨을 보였으며, H3과 H6지점에서는 저주파수에서 높은 음압레벨을 보였다. 이는 수심이 깊은 경우 상류의 저주파수의 음파가 잘 전달되기 때문으로 판단된다. H1과 H11지점은 계단형 여울로 낮은 수심에서 빠른 유속을 가진 H11지점과 느린 유속을 가진 H1 지점에서 대체로 높은 음압레벨을 나타내었다. 이는 낙차에 의한 수중음향 발생에 의한 것으로 판단된다. 세 가지 유형에 따른 수중 음향을 비교하였을 때 음압레벨은 계단형 여울, 여울, 소 순서로 높게 나타났다. 결과적으로 수중음향이 서식처의 수리적 특성에 따라 다양한 특성을 나타내고 있으며, 이를 통해 생물서식처를 평가하기 위한 새로운 방법으로 수중음향의 활용 가능성을 제시하였다.

• Phonetics and Speech Sciences
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• v.10 no.4
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• pp.91-99
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• 2018

Korean stops are currently undergoing a tonogenetic sound change, as found in the Seoul dialect in which a merged VOT of aspirated and lax stops induces F0 to be the primary cue for distinguishing the two stops and the lax stops have lower F0 than the aspirated stops. In tonal languages, low tone is produced with a breathy voice. This study investigated whether there are changes in voice quality with respect to the tonogenetic sound change of Korean stops. Two age groups speaking the Seoul dialect participated in this study: five females and six males born in the 1940s and 1950s and nine females and eight males born in the 1980s and 1990s. This study replicated previous findings of VOT and F0 and further examined H1-H2, H1-A1, and H1-A2 to see how they correlate with the sound change. In the older and younger generations, H1-H2, H1-A1, and H1-A2 were significantly lower after the tense stops than after the aspirated and lax stops, but they were not significantly different after the aspirated and lax stops. However, the younger females exhibited some different results for H1-H2 and H1-A2 than the older generation. In the younger females, the H1-H2 mean was higher after the aspirated stops than it was after the lax stops at the vowel onset, and the H1-H2 difference increased at the vowel midpoint. Although there was an inter-speaker variation in the results of H1-H2 and H1-A1, analyses of individual speakers showed that the H1-H2 and H1-A1 were higher after the lax stops than after the aspirated stops in the younger female speakers. These results indicate that lax stops tend to be breathier than aspirated stops in the younger female speakers. They also indicate that changes in voice quality are on Korean stops with tonal sound change, but are still developing.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.3
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• pp.122-126
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• 2012

The properties of Al-doped ZnO (AZO) films were investigated as a function of $H_2/(Ar+H_2)$ gas ratio using an AZO (2 wt% $Al_2O_3$) ceramic target in a radio frequency (RF) magnetron sputtering system. The deposition process was done at $200^{\circ}C$ and in $2{\times}10^{-2}$ Torr working pressure and with various ratios of $H_2/(Ar+H_2)$ gas. During the AZO film deposition process, partial $H_2$ gas affected the AZO film characteristics. The electron resistivity (${\sim}9.21{\times}10^{-4}\;{\Omega}cm$) was lowest and mobility (${\sim}17.8\;cm^2/Vs$) was highest in AZO films when the $H_2/(Ar+H_2)$ gas ratio was 2.5 %. When the $H_2/(Ar+H_2)$ gas ratio was increased above 2.5 %, the electron resistivity increased and mobility decreased with increasing $H_2/(Ar+H_2)$ gas ratio in AZO films. The carrier concentration increased with increasing $H_2/(Ar+H_2)$ gas ratio from 0 % to 7.5 %. This phenomenon was explained by reaction of hydrogen and oxygen and additional formation of oxygen vacancy. The average optical transmission in the visible light wavelength region over 90 % and an orientation of the deposition was [002] orientation for AZO films grown with all $H_2/(Ar+H_2)$ gas ratios.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.648-655
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• 2007

UV/H_2O_2$, $O_3$, $O_3/H_2O_2$, $UV/H_2O_2/O_3$ processes were tested for the removal of COD and color from terephthalic acid wastewater. COD removal efficiencies were 10, 48, 56, 63% in the $UV/H_2O_2$, $O_3$, $O_3/H_2O_2$, $UV/H_2O_2/O_3$ process respectively. Color removal efficiency of $UV/H_2O_2$ process was 80% and $O_3$, $O_3/H_2O_2$, $UV/H_2O_2/O_3$ processes were almost more than 99%. Terephthalic acid, isophthalic acid and benzoic acid were completely destructed in terephthalic wastewater within 120 min by $UV/H_2O_2/O_3$ process and shows high COD and color removal efficiencies. The optimum concentration of $H_2O_2$ dosage was found to be 0.5 M, 25 mM and 5 mM for $UV/H_2O_2$, $O_3/H_2O_2$ and $UV/H_2O_2/O_3$ processes respectively, Organic destruction efficiency was enhanced and also reducing the consumption of $H_2O_2$ dosage by combining UV, $H_2O_2$ and $O_3$ process.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.7
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• pp.949-955
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• 2020

In this Study, Social Network Analysis of IoT related patents in South Korea, China, and Japan was conducted from the viewpoint of patent informatics. To this end, 2,526 patents filed by PCT until December 2019 were investigated up to the subclass level of the IPC code. As a result, in the case of South Korea, representative IPC codes are in the order of G06Q, H04L, G06F, H04W, and the highest frequency of interconnection is H04L→H04W, H04W→H04L, H04W→H04B. In China, the representative IPC codes are in the order of H04L, H04W, G05B, G06Q. South Korea has strong technological convergence centered on the G06Q, while China has strong convergence centered around H04L and H04W. Moreover, in China, H04L and H04W have more diverse combinations than in South Korea in Section A, B, G, and H. In the future, it is necessary to study the diversity of technology convergence of H04L and H04W in China.