• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3559-3566
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• 2014

Study on the unimolecular reaction for $CH_2FO$ and $CD_2FO$ is carried out. The structures, energy barriers and zero point energy of the three channels in the title unimolecular reactions are computed with the MP2/6-311++G(3df, 3pd) method. RRKM theory is used to calculate the rate constants of canonical case at temperature range of 500-5000 K and microcanonical system at total energy of 19.05-71.68 kcal/mol. The results indicate that the anharmonic effect and isotope effect are very small for the three channels, and the anharmonic rate constants, around $10^9-10^{11}s^{-1}$, are close to the experimental prediction reasonably.

• Journal of Ocean Engineering and Technology
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• v.13 no.2 s.32
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• pp.58-65
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• 1999

The effect of specimen thickness on fatigue crack growth rate was studied. The objective of the present study is to investigate the effect of specimen thickness on the fatigue crack growth behavior at various stress intensity factor ranges and also the variation of material restance to fatigue crack growth. The fatigue crack growth resistance was treated as a spatial stochastic process, which varies randomly on the crack path, Compact tension specimens with a LT orientation for structural steel were used. All testing was done at a constant stress intensity level. The experimental data were analyzed for the size effect to determine the Weibull distributions of the material resistance.

• Journal of Electrical Engineering and Technology
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• v.9 no.5
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• pp.1670-1676
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• 2014

This paper presents the modeling of Single Electron Transistor (SET) based on Physical model of a device and its equivalent circuit. The physical model is derived from Schrodinger equation. The wave function of the electrode is calculated using Hartree-Fock method and the quantum dot calculation is obtained from WKB approximation. The resulting wave functions are used to compute tunneling rates. From the tunneling rate the current is calculated. The equivalent circuit model discuss about the effect of capacitance on tunneling probability and free energy change. The parameters of equivalent circuit are extracted and optimized using genetic algorithm. The effect of tunneling probability, temperature variation effect on tunneling rate, coulomb blockade effect and current voltage characteristics are discussed.

• Bulletin of the Korean Chemical Society
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• v.12 no.1
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• pp.93-97
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• 1991

Rate constants have been measured spectrophotometrically for the reactions of alkali metal ethoxides with 4-nitrophenyl benzoate, S-4-nitrophenyl thiobenzoate and 4-nitrophenyl thionbenzoate in ethanol at 25$^{\circ}$C. Substitution of S for O in the leaving group has not affected reactivity significantly, while the effect of the similar replacement in the acyl group has led to rate decrease by a factor of 10, although pronounced rate enhancements have been expected for both systems. The replacement of O by a polarizable S has also influenced the reactivity of the esters toward alkali metal ethoxides, i.e. the reactivity decreases as the size of the metal ion decreases. The alkali metal ions have showed inhibition effect instead of catalytic effect which would have been expected for the present system. The effect of replaced sulfur atom on the reactivity for the present system is attributed to the nature of hard and soft acids and bases.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.4
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• pp.313-318
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• 1990

Forty-two outbred female Sprague-Dawley rats weighing 145 g were used to study the effects of a beta-agonist, cimaterol, on growth, body composition and urinary excretion of 3-methylhistidine (MH) at 3, 6 and 18 d. Cimaterol (CIM) was administered in the feed at 10 mg/kg. The growth promoting effect of CIM was most evident during the initial part of the feeding period, followed by a gradual decrease in the magnitude of the response with no significant effect at 18 d. The action of CIM was confined to skeletal and cardiac muscles with no stimulating effect on other organs. The amount of urine excretion and urinary MH excretion was reduced (p<.01) at 3 d in the CIM group. No difference was found at 6 d, followed by an increased urine excretion (p<.05) and MH excretion (p<.01) at 18 d. An inverse relationship between growth rate and urinary MH excretion suggested that the increased growth rate of CIM-fed rats during the initial part of the feeding period is primarily attributed to the decreased protein degradation rate. It was further suggested that both fractional synthesis rate and fractional degradation rate increased during the later part of the feeding period.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.1
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• pp.34-38
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• 2005

Effects of pH level and slurry particle size on material removal rate and planarization of langasite single crystal wafer have been examined. Higher material removal rate was obtained with lower pH level slurries while the planarization was found to be determined by average particle size of colloidal silica slurries. Slurries containing 0.045 ㎛ amorphous silica particles showed the best polishing effect without any scratches on the surface. Effective particle number has a strong effect on the surface planarization and the removal rate, so that the lower effective particle numbers produced low removal rate but the better planarization results.

• KIEAE Journal
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• v.13 no.4
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• pp.27-32
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• 2013

This study focus on shaft box facade, special form of box window construction. It consists of a system of box window with continuous vertical shafts that extend over a number of stories to create a stack effect. The subject building was decided by analyzing various types of exiting apartments. Shaft box type balcony was devised by setting up shaft space at a part of balcony. Air flow and indoor air temperature were simulated, performance of shaft box type balcony was compared with existing types using VE computer simulation program. Research consequence can be summarized as follow: 1) In the case of existing types, the change of window opening rate has only a little effect on the improvement of indoor temperature. But, air flow rate increased two times in the case that changed opening rate 20% to 40% 2) In the case of existing types, the growth of air flow rate has little effect on the improvement of indoor temperature. But, shaft box type represented the remarkable effect on the improvement of indoor temperature as well as the growth of air flow rate.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.543-553
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• 2020

This paper examines the effect of COVID-19 pandemic on the Philippine stock exchange, peso-dollar rate and retail price of diesel using robust least squares regression and vector autoregression (VAR). The robust least squares regression using MM-estimation method concluded that COVID-19 daily infection has negative and statistically significant effect on the Philippine stock exchange index, peso-dollar exchange rate and retail pump price of diesel. This is consistent with the results of correlation diagnostics. As for the VAR model, the lag values of the independent variable disclose significance in explaining the Philippine stock exchange index, peso-dollar exchange rate and retail pump price of diesel. Moreover, in the short run, the impulse response function confirmed relative effect of COVID-19 daily infections and the variance decomposition divulge that COVID-19 daily infections have accounted for only minor portion in explaining fluctuations of the Philippine stock exchange index, peso-dollar exchange and retail pump price of diesel. In the long term, the influence levels off. The Granger causality test suggests that COVID-19 daily infections cause changes in the Philippine stock exchange index and peso-dollar exchange rate in the short run. However, COVID-19 infection has no causal link with retail pump price of diesel.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.15-23
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• 2021

This study investigates the presence of the day-of-the-week anomaly in exchange rate for 30 developing countries with free floating exchange rate regimes using daily data from January 2, 2011 to December 31, 2019. First, we apply the GARCH panel to estimate the intraday effect for all the sampled countries. Second, we run poolability test to check whether the coefficients of the GARCH panel are the same for all countries sampled. The result of poolability test rejects the homogeneity assumption. This implies that our sample countries contain heterogeneity. Third, we apply mean-group estimation by averaging the coefficients for all individual GARCH estimations. Fourth, we divided our sample of developing countries into three groups based on capital restriction index for the reason that the effect of monetary policy on the exchange rate depends on the degree of capital account liberalization. The empirical evidence for the return equation suggests that Mondays are connected with lower volatility whereas Thursdays experiences higher return compared to Tuesdays. The lowest estimated coefficient for full sample, group 1 and group 2, is Friday, but for group 2 is Thursday. We find similar result for the volatility equations, which show that Monday returns are lower compared to Tuesday.

• Herbal Formula Science
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• v.10 no.1
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• pp.73-80
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• 2002

We have examined the purgative effect of three Jechun-jun formulas in sprague dawley(SD) rat. Three jechun-jun formulas were Jechun-jun(Sample I ) and augmented Jechun-jun(Sample II) and augmented Jechun-jun add rhubarb(sample III ). We examined the amount and the humidity of feces in rat. The experimental animals were devided into four groups. as control group and three Jechun-jun (sample I, II, III). We administerd the water extract of sample I, II, III to rat per oral for 8days long. After every 24hours measured the amount of wet feces from rats in metabolic cage. Humidity rate of feces from rat was at first measure wet feces for 24hours (W) and measure dried feces (W1) and then we consider W-W1 as humidity. High humidity rate means constipation changes into moistening stool. The amount of wet feces and humidity rate of feces in rats were increased in sample I, II, III. Sample I has highest humidity rate of feces. so showed strong moistening effect. Sample II has mild effect in treating constipation. sample III has most amount of wet feces. in conclusion Jechun-jun has an effect of moistening stool. and augmented Jechun-jun add rhubarb has strong purgative effect.