• KDI Journal of Economic Policy
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• v.14 no.4
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• pp.3-26
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• 1992

The pupose of this paper is to construct a price determination model of the Korean economy and to find out the propogation mechanism of monetary and fiscal policies. The model is a small-size macroeconometric model consisted of ten core equations : consumption, investment, exports, imports, consumer price index, wage rate, corporate bond rate, potential GNP, capital stock, and GNP identity. The model is a Keynesian model : consumer price index is determined by markup over costs, and wage rate is expressed by Phillipse curve ralation. Two features of the model, however, distinguish this model from other macroeconometric models of the Korean economy. First of all, the estimation of potential GNP and the capital stock is endogenized as suggested by Haque, Lahiri, and Montiel (1990). This allows us to calculate the level of excess demand, which is defined as the difference between the actual GNP and the potential GNP. Second, interest rate, inflation and wages are all estimated as endogenous variables. Moreover, all quantity variables include price variables as important determinants. For instance, interest rate is an important determinant of consumption and investment. Exports and imports are determined by the real effective exchange rate. These two features make the interactions between excess demand and prices the driving forces of this model. In the model, any shock which affects quantity variable(s) affects excess demand, which in turn affects prices. This strong interaction between prices and quantities makes the model look like a classical model over the long run. That is, increases in money supply, government expenditures, and exchange rate (the price of the U.S. dollar in terms of Korean won) all have expansionery effects on the real GNP in the short run, but prices, wage, and interest rate all increase as a result. Over the long run, higher prices have dampenning effects on output. Therefore the level of real GNP turns out to be not much different from the baseline level ; on the other hand, the rates of inflation, wage and interest rate remain at higher levels.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.11
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• pp.18-24
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• 2000

(Ba,Sr)$TiO_3$ thin films have attracted great interest as new dielectric materials of capacitors for ultra-large-scale integrated dynamic random access memories (ULSI-DRAMs) such as 1 Gbit or 4 Gbit. In this study, inductively coupled $BCl_3/Cl_2/Ar$ plasmas was used to etch (Ba,Sr)$TiO_3$ thin films. RF power/dc bias voltage=600 W/-250 V and chamber pressure was 10 mTorr. The $Cl_2/(Cl_2+Ar)$ was fixed at 0.2 the (Ba,Sr)$TiO_3$ thin films were etched adding $BCl_3$. The highest (Ba,Sr)$TiO_3$ etch rate is $480{\AA}/min$ at 10 % $BCl_3$ to $Cl_2/Ar$. The change of Cl, B radical density measured by optical emission spectroscopy(OES) as a function of $BCl_3$ percentage in $Cl_2/Ar$. The highest Cl radical density was shown at the addition of 10% $BCl_3$ to $Cl_2/Ar$. To study on the surface reaction of (Ba, Sr)$TiO_3$ thin films was investigated by XPS analysis. Ion bombardment etching is necessary to break Ba-O bond and to remove $BaCl_2$. There is a little chemical reaction between Sr and Cl, but Sr is removed by physical sputtering. There is a chemical reaction between Ti and Cl, and $TiCl_4$ is removed with ease. The cross-sectional of (Ba,Sr)$TiO_3$ thin film was investigated by scanning electron microscopy (SEM), the etch slope is about 65~70$^{\circ}$.

• Journal of the Korean Chemical Society
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• v.47 no.3
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• pp.206-212
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• 2003

The reaction rates of substituted quinolines (6-Clqui., qui.) with p-substituted benzoylchlorides $(p-CH_3,\;p-H,\;p-NO_2)$ have been measured by conductometry in acetonitrile, and the rate constants are determined at various temperatures (10, 15, 20, $25^{\circ}C$) and pressures (1, 200, 500, 1000 bar). From the values of rate constants, the activation parameters $(Ea,\;{\Delta}V^{\neq},\;{\Delta}H^{\neq},\;{\Delta}S^{\neq}, \;{\Delta}G^{\neq})$and the pressure dependence of Hammett ρ values were determined. The rate constants increased with increasing temperatures and pressures, and are further increased to introduction to the electron acceptor substituents in substrate $(p-NO_2)$ with quinoline. The activation volume and the activation entropy are all negative. And the Hammett p values are negative for nucleophile ${\rho}_X$ and positive for the substrate ${\rho}_Y$ over the pressure range studied. The results of kinetic studies for pressure and substituent show that these reactions proceed through a typical $S_N2$ reaction mechanism and "associative $S_N2$" favoring bond formation with increasing pressures.

• BMB Reports
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• v.31 no.6
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• pp.595-599
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• 1998

To investigate conformational information of a low oxygen affinity recombinant hemoglobin (rHb) containing $96Val{\rightarrow}Trp$ mutation at the ${\alpha}96$ position, we ave produced rHb (${\alpha}96Val{\rightarrow}Phe$) and rHb (${\alpha}96Val{\rightarrow}Tyr$), using the Escherichia coli expression system and site-directed mutagenesis. The oxygen affinity of rHb (${\alpha}96Val{\rightarrow}Phe$) is similar to that of human normal adult hemoglobin (Hb A). However, the oxygen affinity of rHb (${\alpha}96Val{\rightarrow}Tyr$) showed much lower oxygen affinity than Hb A which is similar to that of rHb (${\alpha}96Val{\rightarrow}Tyr$), providing an opportunity as a potential candidate for a hemoglobin-based blood substitute. Both rHb (${\alpha}96Val{\rightarrow}Phe$) and rHb (${\alpha}96Val{\rightarrow}Tyr)$ showed high cooperativity in oxygen binding. IH-NMR spectroscopy shows that both rHb (${\alpha}96Val{\rightarrow}Phe$) and rHb (${\alpha}96Val{\rightarrow}Tyr$) have very similar tertiary structure around the heme pockets and uaternary structure in the ${\alpha}_1/{\beta}_2$ subunit interface ompared to Hb A. The low oxygen affinity of rHb (${\alpha}96Val{\rightarrow}Tyr$) has been suggested to be due to a hydrogen bond caused by an extra hydroxyl group not present in rHb (${\alpha}96Val{\rightarrow}Phe$). However, investigation of the carbonmonoxy form of rHb (${\alpha}96Val{\rightarrow}Phe$) and (${\alpha}96Val{\rightarrow}Try$) in the presence of inositol hexaphosphate at low temperature suggests that low oxygen affinity of (${\alpha}96Val{\rightarrow}Try$) may arise from a mechanism different to that of rHb (${\alpha}96Val{\rightarrow}Trp$).

• Journal of the Korean Chemical Society
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• v.25 no.6
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• pp.376-382
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• 1981

The rates and the activation parameters for the reaction of phenacyl bromide with substituted anilines in methanol and dimethylformamide were measured. The effects of substituted anilines were discussed. The rate of the reaction was increased with the electron donating power of substituent and showed larger value in DMF than in MeOH. The isokinetic relationship was shown between ${\delta}H^{\neq}$ and ${\delta}S^{\neq}$, isokinetic temperature was 539 and $400^{\circ}C$ in MeOH and DMF respectively, but p-nitro aniline was deviated from linearity in both solvents caused by solvent effects. The excellent linear relationship between log k and p$K_a$ of substituted anilines was observed by following equation. log k = 0.57p$K_a$-1.28 (r = 0.996) in MeOH at $45^{\circ}C$, log k = 0.65p$K_a$-0.88 (r = 0.970) in DMF at $45^{\circ}C$. From the Hammett plot, this reaction was a nucleophilic displacement of aniline to phenacyl bromide and the following equation was obtained at $45^{\circ}C$. log k/$k_0$ = -2.00${\sigma}$ + 0.06 (r = 0.985) in MeOH; log k/$k_0$ = -2.22${\sigma}$ + 0.08 (r = 0.995) in DMF. Large deviation of p-nitro aniline in DMF is resulted from solvent effects too. From above results, the substituent effect of this reaction can be described as $S_N2$ mechanism and bond formation more proceeds in DMF relative to MeOH.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.565-574
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• 1985

The rates of reaction between 4-substituted-2,6-dinitrochlorobenzenes with para-substituted anilines in methanol-acetonitrile mixtures were measured by conductometry. It was observed that the rate constant increases in the order of X = 4-$NO_2 {\gg}4-CN {\gg}4- CF_3$, where X is a substituent in the substrate. The rate constant also increases in the order of Y = p-O$CH_3{\gg}p- CH_3{\gg}H {\gg}p-Cl{\gg}m- NO_2$, where Y is a substituent in the aniline ring. Kinetic studies in the methanol-acetonitrile solvent system with various nucleophiles showed that the N-C bond forming step is making a great contribution to the overall second order rate constant. The electrophilic catalysis by methanol probably consists of the hydrogen bonding between alcoholic hydrogen and leaving chloride in the transition state. The nucleophilic catalysis by methanol may be ascribed to the formation of hydrogen bonds between alcoholic oxygen and hydrogens of amines in the transition state. All these experimental facts are supporting the operation of $S_N$Ar machanism with the second step being the rate determining. This mechanism can be successfully fitted to the PES model.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.150-156
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• 2007

Some flavonoids have spasmolytic activities in various smooth muscles, but structure-activity relationships on their spasmolytic activity and its mechanism are unclear. In this study, effects of flavones (flavone and apigenin) and flavonols (quercetin and rutin) on the rat ileal smooth muscle contraction were studied in vitro and in vitro. In the electric stimulation-induced contraction, all of four flavonoids inhibited concentration-dependently the rat ileal smooth muscle contraction induced by electric stimulation (10 mV, 0.1 cps, 0.1 msec duration), IC$_{50}$ of quercetin, apigenin, flavone and rutin were 0.98${\times}$10$^{-5}$, 1.20${\times}$10$^{-5}$, 1.55${\times}$10$^{-5}$ and 1.85${\times}$10$^{-5}$ M, respectively. Flavonoids at a concentration of 2${\times}$10$^{-5}$ M also significantly inhibited the anaphylactic contraction and decreased concentration-dependently the mast cell degranulation by anaphylactic reaction, IC$_{50}$ of quercetin, apigenin, flavone and rutin were 4.0${\times}$10$^{-5}$, 7.5${\times}$10$^{-5}$, 8.0${\times}$10$^{-5}$ and 9.5${\times}$10$^{-5}$ M, respectively. These results indicated that flavones and flavonols inhibited the rat ileal smooth muscle contraction induced by electric stimulation because of their antagonism against acetylcholine and have spasmolytic activities on anaphylactic contraction which may be due to their mast cell-stabilizing activities. Furthermore, double bond of C$_{2,3}$ in benzene ring of flavonoids may be important in the their antispasmodic activities on the rat ileal smooth muscle contraction induced by electric stimulation and anaphylactic reaction.

• Korean Journal of Materials Research
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• v.8 no.4
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• pp.345-353
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• 1998

Metal organic chemical vapor deposition (MOCVD) of copper using three Cu( I ) precursors. (hfac)Cu (VTMS) (hfac= hexafluoroacetylacetonate, VTMS= vinyltrimethylsilane), (hfac)Cu(VTMOS) (VTMOS= vinyltri¬methoxysilane) and (hfac)Cu(A TMS) (A TMS= allyltrimethylsilane) was studied. The thermal stability and the gase¬ous phase reaction mechanism of Cu( I ) precursors were identified using $^1H$-, $^I3C$-NMR and Fourier transform infra¬red spectroscopy. It was found out that thermal stability of liquid phase (hfac)Cu(VTMS) and (hfac)Cu(VTMOS) were better than that of (hfac)Cu(A TMS) using FT - NMR. From in-situ FT - IR experiments, the disproportion reaction of Cu(hfac). the decomposition reaction of Cu(hfac), and cracking of free hfac ligand were observed. Also the effect of gaseous phase reaction on the deposition rates and film properties was investigated. The minimum temperature that deposition of copper films from (hfac)Cu(A TMS) was as low as 60$^{\circ}$C and such a low deposition temperature compared with those of other Cu( I ) precursors is believed to be related with weaken Cu- A TMS bond.

• Korea and Global Affairs
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• v.3 no.2
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• pp.183-220
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• 2019

Nowadays, soft power is playing a more important role in international communication and cooperation, and as cultural exchange in regional cooperation is deeply influenced by national soft powers, the development is usually unbalanced. Bangladesh, China, India and Myanmar are adjacent to each other with a long history of intercourse. In the year 2013, initiation of constructing Bangladesh-China-India-Myanmar Economic Corridor advocated by China and India was responded positively by Bangladesh and Myanmar. Since then, the world has witnessed an increasing connection of these four countries. Being the critical bond connecting the southwestern areas of China and Bangladesh, India as well as Myanmar, Bangladesh-China-India-Myanmar Economic Corridor is characterized by multiple regional cultures along with frequent connections in cultural products and activities. However, cultural exchange now is dominated by imbalanced development due to potent soft power of China and India that these two countries export more cultural products to the rest, which has an impact in many fields of Bangladesh and Myanmar. Priority should be given to coordinated development in cultural exchange regarding the construction of Bangladesh-China-India-Myanmar Economic Corridor. Only by developing a sustainable development mechanism for cultural exchange, to coordinate the influences of soft powers of these four countries, then a fine complexion of "all flowers are in bloom" can be created, returning to five original intention of the construction of this economic corridor: "Policy Communication" and "Strength People-to-people Ties", etc.

• Journal of the Korean Vacuum Society
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• v.20 no.1
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• pp.42-49
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• 2011

We deposited $SiN_x$ thin films by using PECVD technique at $200^{\circ}C$ with various flow ratios of the $SiH_4/N_2$ gases. The photoluminescence measurements revealed that the maximum emission wavelength shifted to long wavelength as the ratio increased, however, positions of the several peak wavelengths, such as 1.9, 2.2, 2.4, and 3.1 eV, were independent on the ratio. Changes of the photoluminescence spectra were measured in the $N_{2}-$, $H_{2}-$, and $O_2$-annealed films. The luminescence intensities increased after the annealing process. In particular, the maximum emission wavelength shifted to short wavelength after $H_{2}-$ or $O_2$-annealing. But there were still several peaks on the spectra of all annealed films, several peak positions remained to be unchanged after the annealing. As for the light emission mechanism, we have considered the defect states of the Si- and N- dangling bonds in the $SiN_x$ energy gap, so that the energy transitions from/to the conduction/valence bands and the defect states in the gap were attributed to the light emission in the $SiN_x$ films. The experimental results point to the possibility of a Si-based light emission materials for flexible Si-based electro-optic devices.