• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.7A
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• pp.967-977
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• 2000

In this paper, we apply a mixed $H_2/H_{\infty}$ control to a generalized plant of inverted pendulum system represented by an LFR(Linear Fractional Representation). First, in order to obtain the generalized plant, the linear model of the inverted pendulum represented by an LFR(Linear fractional Representation) is derived. In LFR, we consider system uncertainties as three nonlinear components and a pendulum mass uncertainty. Augmenting the LFR model by adding weighting functions, we get a generalized plant. And then, we design a mixed $H_2/H_{\infty}$ controller for the generalized plant. In order to design the mixed $H_2/H_{\infty}$ controller, we use 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. In the result, with the fewer feedback information, 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.

• Journal of Surface Science and Engineering
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• v.44 no.5
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• pp.201-206
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• 2011

Fe-2%Mn-0.5%Si alloys were corroded at 600, 700 and $800^{\circ}C$ for up to 70 h in 1 atm of $N_2$ gas, or 1 atm of $N_2/H_2O$-mixed gases, or 1 atm of $N_2/H_2O/H_2S$-mixed gases. Oxidation prevailed in $N_2$ and $N_2/H_2O$ gases, whereas sulfidation dominated in $N_2/H_2O/H_2S$ gases. The oxidation/sulfidation rates increased in the order of $N_2$ gas, $N_2/H_2O$ gases, and, much more seriously, $N_2/H_2O/H_2S$ gases. The base element of Fe oxidized to $Fe_2O_3$ and $Fe_3O_4$ in $N_2$ and $N_2/H_2O$ gases, whereas it sulfidized to FeS in $N_2/H_2O/H_2S$ gases. The oxides or sulfides of Mn or Si were not detected from the XRD analyses, owing to their small amount or dissolution in FeS. Since FeS was present throughout the whole scale, the alloys were nonprotective in $N_2/H_2O/H_2S$ gases.

• Journal of the Korean Institute of Intelligent Systems
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• v.12 no.3
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• pp.239-245
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• 2002

In this Paper, we present a method for designing fuzzy $H_2/H_{\infty}$ controllers of delayed nonlinear systems with saturating input. Takagi-Sugeno fuzzy model is employed to represent delayed nonlinear systems with saturating input. The fuzzy control systems utilize the concept of the so-called parallel distributed compensation(PDC). Using a single quadratic Lyapunov function, the globally exponential stability and $H_2/H_{\infty}$ performance problem are discussed. And a sufficient condition for the existence of fuzzy $H_2/H_{\infty}$ controllers is given in terms of linear matrix inequalities(LMIs). The designing fuzzy $H_2/H_{\infty}$ controllers minimize an upper bound on a linear quadratic performance measure. Finally, a design example of fuzzy $H_2/H_{\infty}$ controller for uncertain delayed nonlinear systems with saturating input.

• Bulletin of the Korean Chemical Society
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• v.7 no.6
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• pp.466-468
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• 1986

Reaction of $Ir(ClO_4)(CO)(PPh_3)_2$ with trans-$C_6H_5CH$ = $CHCO_2C_2H_5$ produces a new cationic iridium(I) complex, [Ir (trans-$C_6H_5CH$ = $CHCO_2C_2H_5)(CO)(PPh_3)_2]ClO_4$ where trans-$C_6H_5CH$ = $CHCO_2C_2H_5$ seems to be coordinated through the carbonyl oxygen rather than through the $\pi$-system of the olefinic group according to the spectral data. It has been found that Ir$(ClO_4)(CO)(PPh_3)_2$ catalyzes the hydrogenation of $CH_2$ = $CHCO_2C_2H_5$, trans-$CH_3CH$ = $CHCO_2C_2H_5$ and trans-$C_6H_5CH$ = $CHCO_2C_2H_5$ to $CH_3CH_2CO_2C_2H_5$, $CH_3CH_2CH_2CO_2C_2H_5$ and $C_6H_5CH_2CH_2CO_2C_2H_5$, respectively at room temperature under the atmospheric pressure of hydrogen. The relative rates of the hydrogenation of the unsaturated esters are mostly understood in terms of steric reasons.

• Resources Recycling
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• v.11 no.2
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• pp.3-13
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• 2002

The characteristics of cyanide decomposition in aqueous phase by hydrogen peroxide have been explored in an effort to develop a process to recycle waste water. The self-decomposition of $H_2O$$_2$at pH 10 or below was minimal even in 90 min., with keeping about 90% of $H_2O$$_2$undissociated. On the contrary, at pH 12 only 9% of it remained during the same time. In the presence of copper catalyst at 5 g Cu/L, complete decomposition of $H_2$O$_2$was accomplished at pH 12 even in a shorter time of 40 min. The volatility of free cyanide was decisively dependent on the solution pH: the majority of free cyanide was volatilized at pH 8 or below, however, only 10% of it was volatilized at pH 10 or above. In non-catalytic cyanide decomposition, the free cyanide removal was incomplete in 300 min. even in an excessive addition of $H_2$$O_2$at a $H_2$$O_2$/CN molar ratio of 4, with leaving behind about 8% of free cyanide. On the other hand, in the presence of copper catalyst at a Cu/CN molar ratio of 0.2, the free cyanide was mostly decomposed in only 16 min. at a reducedH202/CN molar ratio of 2. Ihe efnciency of HBO2 in cyanide decomposition decreased with increasing addition of H2O2 since the seu-decomposition rate of $H_2$$O_2$increased. At the optimum $H_2$$O_2$/mo1ar ratio 0.2 of and Cu/CN molar ratio of 0.05, the free cyanide could be completely decomposed in 70 min., having a self-decomposition rate of 22 mM/min and a H$_2$$O_2$ efficiency of 57%.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.176-185
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• 1995

To improve photosensisitizing efficiency of ZnO/$H_2Pc(I)_x$ system, ZnO/$H_2Pc(I)_x$ system was dispersed in a typical photoconductive polymer of poly(9-vinylcarbazole)(PVCZ). The iodine dopant level(x) of ZnO/${\chi}-H_2Pc(I)_x$ is proportional to concentration of iodine, whereas x of ZnO/${\beta}-H_2Pc(I)_x$ decreased from the highest x=0.97 at more than $6.3{\times}10^{-3}$ M iodine solution. The Raman spectra of ZnO/${\chi}-H_2Pc(I)_x$ at 514 nm exhibited characteristic $I_3^-$ patterns in the range of 50∼550 $cm^{-1}$ at $x{\geq}0.57.$ The surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.48}$/PVCZ was approximately 1.6 times greater than ZnO/${\chi}-H_2 Pc(I)_{0.48}$ and was 1.8 times of ZnO/${\chi}-H_2Pc(I)_{0.57}$/PVCZ at 670 nm. With ZnO/$H_2Pc(I)_x$/PVCZ, the highest iodine dopant levels showed a higher photovoltage. Therefore the injection of holes from H2Pc into PVCZ resulted in that photosensisitizing effect of ZnO/$H_2Pc(I)_x$/PVCZ system was improved compared to ZnO/$H_2Pc(I)_x$ case.

• Archives of Pharmacal Research
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• v.29 no.7
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• pp.535-540
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• 2006

Several novel 1-[2-(1H-tetrazol-5-yl) ethyl]-1H-benzo[d][1,2,3]triazoles (3a-h) have been synthesized by the condensation of 1-[2-(1H-tetrazol-5-yl)-ethyl]-1H-benzotriazole (2) and appropriate acid chlorides. 1-[2-(1H-tetrazol-5-yl)-ethyl]-1H-benzotriazole (2) was synthesized by reacting 3-(1H-benzo[d][1,2,3]triazol-1-yl)propanenitrile with sodium azide and ammonium chloride in the presence of dimethylformamide. The synthesized compounds were characterized by IR and PMR analysis. The titled compounds were evaluated for their in vitro antibacterial and antifungal activity by the cup plate method and anticonvulsant activity evaluated by the maximal electroshock induced convulsion method in mice. All synthesized compounds exhibited moderate antibacterial activity against Bacillus subtilis and moderate antifungal activity against Candida albicans. Compounds 5-(2-(1 H-benzo[d][1,2,3]triazo-1-yl)ethyl)-1H-tetrazol-1-yl)(4-aminophenyl)methanone 3d and 5-(2-(1 H-benzo[d][1,2,3]triazo-1-yl)ethyl)-1H-tetrazol-1-yl)(2-aminophenyl)methanone 3e elicited excellent anticonvulsant activity.

• Journal of the Korean Chemical Society
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• v.55 no.1
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• pp.28-37
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• 2011

Spectroscopic (infrared, electronic and $1^H$-NMR), elemental analyses CHN, molar conductivity, thermogravimetric analyses (TGA/DTG) and biological studies, of both benzanthrone derivatives 3-N-2-hydroxy ethylamine benzanthrone (HEAB) and 3-N-2-amino ethylamine benzanthrone (AEAB) with Cu(II), Co(II) and Ni(II) chlorides were discussed herein. Based on the above studies, HEAB ligand was suggested to be coordinated to each metal ions via hydroxo and amino groups to form [Cu(HEAB)$(Cl)_2$].$2H_2O$, [Co(HEAB)$(Cl)_2(H_2O)_2$].$8H_2O$ and [Ni(HEAB)$(Cl)_2(H_2O)_2$].$7H_2O$ coordinated complex. On the other hand, AEAB has an octahedral coordinated feature with formulas [Cu(AEAB)$(Cl)_2(H_2O)_2$].$2H_2O$, [Co(AEAB)$(Cl)_2(H_2O)_2$].$4H_2O$ and [Ni(AEAB)$(Cl)_2(H_2O)_2$]. $6H_2O$. The molar conductance values at $25{\circ}C$ for all complexes in DMF are slightly higher than free ligands; this supported the presence of chloride ions inside the coordination sphere. Both benzanthrone ligands and their complexes have been screened against different kinds of bacteria.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.3
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• pp.157-165
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• 2008

In the previous study, the anti-oxidant activity of oxtract/fraction of Sueada aspparagoides(SA) and the stability test for the cream containing SA extract were investigated respectively[1,2]. In this study, the components of SA extract were analyzed by TLC, HPLC, and LC/ESI-MS/MS, $^1H$-NMR. TLC chromatogram of ethyl acetate fraction of SA extract revealed 5 bands $(SA1{\sim}SA5)$. HPLC chromatogram of aglycone fractions obtained from deglycoylation reaction of ethyl acetate fraction showed 2 bands (SAA 2 and SAA 1), which were identified as quercetin (composition ratio, 16.88%) and kaempferol (83.12%) in the order of elution time. Among 5 bands of TLC chromatogram, 4 bands $(SA2{\sim}SA5)$ also were Identified as kaempferol-3-O-glucoside (SA 2), quercetin-3-O-glucoside (SA3), kaempferol-3-O-rutinoside (SA 4), quercetin-3-O-rutinoside (SA 5) by LC/ESI-MS/MSMS/MS. respectively. The spectrum generated for SAA 1 by LC/ESI-MS/MS in the negative ion mode also gave the ion corresponding to the deprotonated aglycone $[M-H]^-$ (285m/z), the $^1H$-NMR spectrum contained signals [${\delta}$ 6.19 (1H, d, J=1.8Hz, H-6), ${\delta}$ 6.44 (1H, d, J=1.8Hz, H-8), ${\delta}$ 6.92 (2H, d, J=9.0Hz, H-3', 5'), ${\delta}$ 8.04 (2H, d, J=9.0Hz, H-2', 6', thus SAA 1 was identified as kaempferol. SAA 2 yielded the deprotonated agycone ion $[M-H]^-$ (301m/z), $^1H$-NMR spectrum showed signals [${\delta}$ 6.20 (1H, d, J=2.0Hz, H-6), ${\delta}$ 6.42 (1H, d, J=2.0Hz, H-8), ${\delta}$ 6.90 (1H, d, J=8.6Hz, H-5'), ${\delta}$ 7.55 (1H, dd, J=8.6, 2.2Hz, H-6'), ${\delta}$ 7.69 (1H, d, J=2.2Hz, H-2', thus SAA 2 was Identified as quercetin. In conclusion, with the anti-oxidant activity and the stability test reported previously, component analysis of SA extracts could be applicable to new cosmeceuticals.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.231-239
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• 2019

Suppressor of Variegation 3-9 Homolog 2 (SUV39H2) methylates the lysine 9 residue of histone H3 and induces heterochromatin formation, resulting in transcriptional repression or silencing of target genes. SUV39H1 and SUV39H2 have a role in embryonic development, and SUV39H1 was shown to suppress cell cycle progression associated with Rb. However, the function of human SUV39H2 has not been extensively studied. We observed that forced expression of SUV39H2 decreased cell proliferation by inducing $G_1$ cell cycle arrest. In addition, SUV39H2 was degraded through the ubiquitin-proteasomal pathway. Using yeast two-hybrid screening to address the degradation mechanism and function of SUV39H2, we identified translationally controlled tumor protein (TCTP) as an SUV39H2-interacting molecule. Mapping of the interacting regions indicated that the N-terminal 60 amino acids (aa) of full-length SUV39H2 and the C-terminus of TCTP (120-172 aa) were critical for binding. The interaction of SUV39H2 and TCTP was further confirmed by co-immunoprecipitation and immunofluorescence staining for colocalization. Moreover, depletion of TCTP by RNAi led to up-regulation of SUV39H2 protein, while TCTP overexpression reduced SUV39H2 protein level. The half-life of SUV39H2 protein was significantly extended upon TCTP depletion. These results clearly indicate that TCTP negatively regulates the expression of SUV39H2 post-translationally. Furthermore, SUV39H2 induced apoptotic cell death in TCTP-knockdown cells. Taken together, we identified SUV39H2, as a novel target protein of TCTP and demonstrated that SUV39H2 regulates cell proliferation of lung cancer cells.