• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.67-76
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• 2009

The development of a variety of methods like AM1, PM3, PM5 and DFT now allows the calculation of atomic and molecular properties with high precision as well as the treatment of large molecules with predictive power. In this paper, these methods have been used to calculate a number of quantum chemical descriptors (like Klopman atomic softness in terms of $E_n^{\ddag}\;and\;E_m^{\ddag}$, chemical hardness, global softness, electronegativity, chemical potential, electrophilicity index, heat of formation, total energy etc.) for 75 alkanes to predict their boiling point values. The 3D modeling, geometry optimization and semiempirical & DFT calculations of all the alkanes have been made with the help of CAChe software. The calculated quantum chemical descriptors have been correlated with observed boiling point by using multiple linear regression (MLR) analysis. The predicted values of boiling point are very close to the observed values. The values of correlation coefficient ($r^2$) and cross validation coefficient ($r_{cv}^2$) also indicates the generated QSPR models are valuable and the comparison of all the methods indicate that the DFT method is most reliable while the addition of Klopman atomic softness $E_n^{\ddag}$ in DFT method improves the result and provides best correlation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.12
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• pp.2655-2661
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• 2009

In this paper, an accurate noise parameters for thermal noise modeling of short channel MOSFET is derived and extracted. Fukui model for calculating the noise parameters of a MOSFET is modified by considering effects of parasitic elements in short channel, and it is compared with conventional noise model equation. In addition, for obtaining the intrinsic noise sources of devices, noise parameters(minimum noise figure $F_{min}$, equivalent noise resistance $R_n$ optimized source admittance $Y_{opt}=G_{opt}+B_{opt}$) in submicron MOSFETs is extracted. With this extraction method, the intrinsic noise parameters of MOSFET without effects of probe pad and extrinsic parasitic elements from RF noise measurements can be directly obtained.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.217-222
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• 2014

This study was performed to evaluate the sporicidal efficacy of a fumigation disinfectant containing 20% ortho-phenylphenol against Clostridium perfringens (C. perfringens) spores. In this research, efficacy test of fumigant against C. perfringens spores was carried out according to French standard NF T 72-281. C. perfringens spores working culture suspension number (N value), all the spore numbers on the carriers exposed with the fumigant (n1, n2, and n3), the number of bacterial spore suspensions by pour plate method (N1), the number of bacterial spore suspensions by filter membrane method (N2) and the mean number of bacterial spore recovered on the control-carriers (T value) were obtained from the preliminary test. In addition, the reduction number of C. perfringens spores exposed with the fumigant (d value) was calculated using T value, the mean number of bacterial spore in recovery solution (n'1) and the mean number of bacterial spore on carriers plated in agar (n'2). N value was $4.3{\times}10^7spores/mL$, and n1, n2, and n3 were higher than 0.5N1, 0.5N2 and 0.5N1, respectively. Additionally, T value was $4.9{\times}10^5spores/carrier$. In the sporicidal effect of the fumigant, the d value was 4.52log reduction. According to the French standard for the fumigant, the d value for the effective sporicidal fumigant should be over than 3log reduction. The results indicated that Fumagari $OPP^{(R)}$ had an efficient sporicidal activity against spores of C. perfringens, then the fumigant can be applied to disinfect food materials and kitchen appliances contaminated with bacterial spores.

• Journal of the Korean Chemical Society
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• v.24 no.3
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• pp.193-200
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• 1980

The crystal structure of N-acetyl-L-cysteine, $C_5H_9NO_3S,$ has been determined from three dimensional photographic intensity data $(CuK{\alpha}$ radiation) by single crystal X-ray diffraction analysis. There is one formula unit in the triclinic unit cell with a = 7.04(3), b = 5.14(2), c = 8.25(3) ${\AA}$, ${\alpha}$ = 106(2), ${\beta}$ = 51(1), ${\gamma}$ = 124(2)$^{\circ}$ and space group P$_1$, The structure was solved by the direct method and refined by the full matrix least-squares method. The final R value is 12.3% for 629 observed reflections. The C-carboxyl group and the N-acetyl group are very neary planar. The molecule appears to form with neighboring molecules a hydrogen bond, $O-H{\cdot}{\cdot}{\cdot}O(3)$ of length 2.59${\AA}$.

• Proceedings of the KIEE Conference
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• 1992.07b
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• pp.710-713
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• 1992

An AVR for OLTC controls motor tap in transformer in order to supply constant power source. Recently for society which is higher informative and more automatic, in our research, the digital AVR for OLTC is developed that can perform more functions and higher functions ( mesurement, display, protection, control ) using microprocessor in a different control method than the conventional AVR. The experiment result is also present.

• Proceedings of the KIEE Conference
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• 2008.10c
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• pp.177-179
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• 2008

This paper, we proposed the theoretical model which includes series resistance $R_s$ and shunt resistance $R_{sh}$ of single-crystalline PV module and used numerical method based on physics. Series resistance $R_s$ was derived from approach for p-n junction diode instead of established form obtained from the simulator with irradiance changes. Electrical output characteristics for PV modules to count the effect of $R_s$ were then studied. Finally simulation results were compared to experimental data leading to good agreement.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.149-159
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• 1998

In order to observe the anticellulolytic localization in the epithelia of the digestive tract such as esophagus, crop, and intestine of a Korean land snail N. samarangae, a cytochemical method and a immunogold labelling method were applied. For the cytochemical study on the cellulase activity, Benedict reaction method applied. And for the immunocytochemical study, the rabbit serum immunoglobuins (IgG) was obtained from the rabbits injected with cellulase which was extracted from body fluid of the snail. The digestive tract tissues of N. samarangae were fixed with 4% paraformaldehyde and 2% OsO4 and embedded in Lowicryl K4M at -40$^{\circ}C$ under UV light (360 nm). The thin sections were loaded on the nickel grids and stained with the serum IgG and protein A-gold complex (particle size: 10 nm). Observations were undertaken with transmission electron microscope (Jeol, JEM-1010). The epithelium of the digestive tract was consisted of five types of cells. In the cytochemical study, the reaction products were found along the periphery of the vacuoles derived from the Bebedict reaction. In the immunocytochemical study, the protein-A gold particles were selectively labelled in Type 1, Type 3 and Type 4 cells in intestinal tissue. membranes of rER, in the surrounding cytoplasm of the rER and secretory granules, and in the apical cytoplasm of the cells. On the material being secreted from the apical cytoplasm was also labelled with the immunogold particles. The all results obtained throughtout present study suggest that the intestinal epithelium of the snail N. samarangae seretes cellulase as one of digestive enzymes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.6
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• pp.981-989
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• 2015

In a log likelihood ratio(LLR) calculation of the detected symbol, multiple-input multiple-output(MIMO) system applying an optimal or suboptimal algorithm such as a maximum likelihood(ML) detection, sphere decoding(SD), and QR decomposition with M-algorithm Maximum Likelihood Detection(QRM-MLD) suffers from exponential complexity growth with number of spatial streams and modulation order. In this paper, we propose a LLR calculation method with very low complexity in the QRM-MLD based symbol detector for a high order modulation based $N_T{\times}N_R$ MIMO system. It is able to approach bit error rate(BER) performance of full maximum likelihood detector to within 1 dB. We also analyze the BER performance through computer simulation to verify the validity of the proposed method.

• Korean Journal of Crystallography
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• v.15 no.2
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• pp.99-103
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• 2004

The structure of $C_{16}H_{19}O_2N_3CuCl_2\;{\cdot}\;H_2O$ has been determined by X-ray diffraction methods. The crystal system is triclinic, space group Pl, unit cell constants. $a=7.6202(9)\; \AA,\; b=8.5943(7) \AA,\; c= 8.6272(6) \AA,\; \alpha= 67.518(6)^{\circ}.\; \beta= 68.043(8)^{\circ},\; \gamma=74.370(8)^{\circ},\; V=478.89(8)\; \AA^3,\; T=295K,\; Z=1,\; D_c=1.504Mgm^{-3}$The intensity data were collected on an Enraf-Nonius CAD-4 Diffractometer with graphite monochromated $MoK\alpha$ radiation $(\alpha=0.7107\;\AA)$. The molecular structure was solved by direct method.』 and refined by full-matrix least squares to a final $R=2.47\%$ for 1659 unique observed $F_0>4\sigma(F_0)$ reflections and 234 parameters.

• Economic and Environmental Geology
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• v.46 no.1
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• pp.1-9
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• 2013

We proposed the revised full-pattern-fitting method of illite polytype quantification with background correction and scale factor correction of WILDFIRE(C) simulated pattern, and R% value ((${\sum}$|simulated-measured|/simulated)/ $n{\times}100$) calculation, and then verified the reliability of this method by applying for the test sample ($2M_1$:1M$$\frac{._-}{.}$$1:1), and by comparing the result with Grathoff and Moore method (1996). We confirmed that the proposed method showed the error range of less than 3.6%, which is much lower than the previous full-pattern-fitting methods, in spite of the impurities of the test sample. In the comparison with Grathoff and Moore method for 2 tested samples, we obtained the relatively higher $2M_1$ contents using Grathoff and Moore method, whereas we obtained the reliable results with less than 10% of R% values.