• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.37.4-38
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• 2018

The HULQ project proposes to use gravitational lensing to determine the masses of QSO host galaxies, an otherwise difficult goal. If these host galaxy masses, along with their SMBH masses from single-epoch measurements, are estimated for a substantial number of QSOs at various redshifts, the co-evolution of SMBHs and their host galaxies can be studied for a large portion of the history of the universe. To determine the feasibility of this study, we present how to estimate the number of sources lensed by QSO hosts, i.e. the number of lensing QSO host galaxies (hereafter QSO lenses). SMBH masses in the literature are transformed into the velocity dispersions of their host galaxies using the M_BH -sigma relation, and in turn the Einstein radii for each QSO -source redshift combination is calculated, assuming singular isothermal spherical mass distributions. Using QSOs and galaxies as potential sources, the probability of a QSO host galaxy being a QSO lens is calculated, as a function of limiting magnitude. The expected numbers of QSO lenses are estimated for ongoing and future wide-imaging surveys, and the Hyper Suprime-Cam Wide survey is illustrated as an example.

• Structural Engineering and Mechanics
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• v.27 no.4
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• pp.425-438
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• 2007

Large changes in stiffness associated with cracking and yielding of reinforced concrete sections may be expected to occur during the dynamic response of reinforced concrete frames to earthquake ground shaking. These changes in stiffness in stories that experience cracking might be expected to cause relatively large peak interstory drift ratios. If so, accounting for such changes would add complexity to seismic design procedures. This study evaluates changes in an index parameter to establish whether this effect is significant. The index, known as the coefficient of distortion (COD), is defined as the ratio of peak interstory drift ratio and peak roof drift ratio. The sensitivity of the COD is evaluated statistically for five- and nine-story reinforced concrete frames having either uniform story heights or a tall first story. A suite of ten ground motion records was used; this suite was scaled to five intensity levels to cause varied degrees of damage to the concrete frame elements. Ground motion intensity was found to cause relatively small changes in mean CODs; the changes were most pronounced for changes in suite scale factor from 0.5 to 1 and from 1 to 4. While these changes were statistically significant in several cases, the magnitude of the change was sufficiently small that values of COD may be suggested for use in preliminary design that are independent of shaking intensity. Consequently, design limits on interstory drift ratio may be implemented by limiting the peak roof drift in preliminary design.

• BMB Reports
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• v.29 no.4
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• pp.300-307
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• 1996

ATP and ADP are potential regulators of mitochondtial respiration and at physiological concentrations they affect the rate of electron transfer between cytochrome c and cytochrome c oxidase. The electron transfer, however, depends on the electrostatic interaction between the two proteins. In order to exclude any nonspecific ionic effects by these polyvalent nucleotides, we used 2'-O-(2,4,6)trinitro(TNP)-derivatives of ATP and ADP which have three orders of magnitude higher affinity for cytochrome c oxidase. A simple titration of the fluorescence intensity of TNP by cytochrome c oxidase showed a binding stoichiometry of 2:1 cytochrome c:cytochrome c oxidase. Higher ionic strength was required for TNP-ATP than for TNP-ADP to be dissociated from cytochrome c oxidase, indicating that the negative charges on the phosphate group are at least partially responsible for the binding. In both spectrophotometric and polarographic assays, addition of ATP (and ADP to a less extent) showed an enhanced cytochrome c oxidase activity. Both electron paramagnetic resonance and fluorescence spectra indicate that there is no Significant change in the cytochrome c-cytochrome c oxidase interaction. Instead, reduction levels of the cytochromes at steadystate suggest that the increased activity of nucleotide-bound cytochrome c oxidase is due to faster electron transfer from cytochrome ${\alpha}$ to cytochrome ${\alpha}_3$, which is known to be the fate limiting step in the oxygen reduction by cytochrome c oxidase.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.10
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• pp.2699-2709
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• 1995

This investigation reports on the study of the ambient turbulent effects on the droplet vaporization in the fuel spray combustion. For tractability, this discussion considers a single droplet in an infinite turbulent flow. In this numerical study, the low-Reynolds-number version of k-.epsilon. turbulence model was used to represent the turbulence effects. The set of two-dimensional conservation equations which describe the transport phenomena in turbulent flow using the mean flow quantities including the droplet internal laminar motion, are solved numerically with the finite difference procedure of Patankar(SIMPLER). The evaluation of the computational model is provided by two limiting cases: turbulent flow over the solid sphere and the laminar flow over a liquid drop. The results show that the turbulence effects are noticeable for the vaporization at high turbulence intensity (10-50%) which is encountered in a typical spray. The magnitude of turbulence effects mainly depends on the turbulent intensity. These effects are not sensitive to the Reynolds number in the range of 50 to 200, ambient temperature in the range of 700 to 1000.deg. K and the volatility.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3587-3591
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• 2011

The reactions of O,O-diethyl Z-S-aryl phosphorothioates with X-benzylamines are kinetically investigated in dimethyl sulfoxide at $85.0^{\circ}C$. The Hammett (log $k_2$ vs ${\sigma}x$) and Br$\ddot{o}$nsted [log $k_2$ vs $pK_a$(X)] plots are biphasic concave downwards for substituent X variations in the nucleophiles with a break point at X = H. The signs of the cross-interaction constants (${\rho}xz$) are positive for both the strongly and weakly basic nucleophiles. Considerably great magnitude of ${\rho}xz$ (= 6.56) value is observed with the weakly basic nucleophiles, while ${\rho}xz$ = 0.91 with the strongly basic nucleophiles. Proposed reaction mechanism is a stepwise process with a rate-limiting leaving group expulsion from the intermediate involving a backside nucleophilic attack with the strongly basic nucleophiles and a frontside attack with the weakly basic nucleophiles. The kinetic results are compared with those of the benzylaminolysis of O,O-diphenyl Z-S-aryl phosphorothioates.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.873-875
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• 2003

It is well known that $I_c$ (critical current) in HTS tape is more sensitive to $B{\perp}$ (magnetic field amplitude applied perpendicular to the tape surface) than to B// (magnetic field amplitude applied parallel to the tape surface). Thus, the magnitude of $B{\perp}$ at HTS tape is important to the design of HTS motor, because it determines the operating current. In addition, the $I_c$ of HTS field coil is determined by not only the $B{\perp}$ but also stress and strain condition at given operating temperature. Therefore, at the stage of field coil design, stress and strain conditions should be considered because when the HTS tape is handled, it is necessary to know the limiting values of loading, bending and twisting to avoid any damages. The $I_c$ of field coil is calculated by 3D analysis and measured through experiments considering the $B{\perp}$ and the margin of contacts loss.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.941-942
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• 2007

The superconducting fault current limiter (SFCL) consists of superconducting coil for limiting the fault current and cryogenic cooling system for keeping the coil in superconducting condition. The study on the insulation design for superconducting coil and cryogenic cooling system should be elaborately performed to develop a high voltage SFCL. In this paper, insulation design of solenoid coil for 13.2kV/630A SFCL is performed through the AC dielectric breakdown test and lightning impulse dielectric strength test. The dependence of dielectric characteristics on the magnitude of liquid nitrogen pressure is also investigated. Through the investigation, it is verified that dielectric characteristics of sub-cooled nitrogen are strongly enhanced by the pressurization. The electrical insulation design of 13.2kV/630A SFCL is performed by applying the experimental results. The successful insulation design for development of 13.2kV/630A SFCL is confirmed by AC dielectric breakdown tests.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.152-161
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• 1992

Selective quenching of 1, 6-diphenyl-1, 3, 5-hexatriene (DPH) by trinitrophenyl groups was utilized to examine the transbilayer fluidity asymmetry of model membranes of phospholipids (SPMVPL) extracted from synaptosomal plasma membrane vesicles (SPMV). The polarization (P), anisotropy (r), limiting anisotropy $(r_\infty$), and order parameter (S) of DPH in the inner monolayer were 0.019, 0.014, 0.018, and 0.047, respectively, greater than calculated for the outer monolayer of SPMVPL. Selective quenching of DPH by trinitrophenyl groups was also utilized to examine the effects of n-alkanols on the individual monolayer structure of SPMVPL. n-Alkanols fluidized the hydrocarbon region of bulk SPMVPL and the potencies of n-alkanols up to 1-nonanon increased with carbon chain length. It appears that the potencies in bilayer fluidization increase by 1 order of magnitude as the carbon chain length increases by two carbon atoms. The cut-off phenomenon was reached at 1-decanol, where further increase in hydrocarbon length resulted in a decrease in pharmacological activity. The n-alkanols had greater fluidizing effects on the outer monolayer as compared to the inner monolayer of SPMVPL, even though these selective effects tended to become weaker as the carbon chain length increased. Thus, it has been proven that n-alkanols exhibit selective rather than nonselective fludizing effects within transbilayer domains of SPMVPL.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.77.3-77.3
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• 2019

Aims. The evolution of scaling relations between SMBHs and their host galaxies becomes uncertain at high redshifts. The HULQ project proposes to use gravitational lensing to measure the masses of QSO host galaxies, an otherwise difficult goal. SMBH masses of QSOs are relatively easy to determine using either reverberation mapping or the single-epoch method. These measurements, if made for a substantial number of QSOs at various redshifts, will allow us to study the co-evolution of SMBHs and their host galaxies. To determine the feasibility of this study, we present how to estimate the number of sources lensed by QSO hosts, i.e. the number of deflector QSO host galaxies (hereafter QSO lenses). Method and results. Using SMBH masses measured from SDSS DR14 spectra, and the M_BH - Sigma relation, the Einstein radii are calculated as a function of source redshift, assuming singular isothermal sphere mass distributions. Using QSOs and galaxies as sources, the probability of a QSO host galaxy being a QSO lens is calculated, depending on the limiting magnitude. The expected numbers of QSO lenses are estimated for ongoing and future wide-imaging surveys, and additional factors that may affect these numbers are discussed.

• Journal of the Korean earth science society
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• v.36 no.7
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• pp.661-673
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• 2015

UBVI CCD photometry of the intermediate age open cluster NGC 7790 has been obtained using AZT-22 1.5 m telescope (f/7.74) at the Maidanak Astronomical Observatory in Uzbekistan. NGC 7790 contains three ${\delta}$ Cep variable stars including CEa Cas, CEb Cas, and CF Cas. PSF photometry was carried out using IRAF/DAOPHOT for all observations. The total number of stars observed both in V and I filter was 1008 and the limiting magnitude was $V{\approx}22$. To determine atmospheric extinction coefficients and photometric zero points, many blue and red standard stars as well as the standard stars in the celestial equator under various airmass were observed. Photometric data were transformed into the standard Johnson-Cousins' UBVI standard system. From the analysis of UBVI color-magnitude diagram and color-color diagram, the color excess in V and I filter [$E(B-V)=0.58{\pm}0.02$], the selective extinction ratio in V and I filter [$R_V{\equiv}A_V/E(B-V)=3.02{\pm}0.09$] and distance modulus ($V_0-M_V=12.65{\pm}0.10$) of the cluster were determined. The age of the cluster was estimated to be log $age=8.05{\pm}0.05$ [yr] based on the position of these three Cepheid variables in the color-magnitude diagram, the isochrone of the Geneva group ($Ekstr{\ddot{o}}m$ et al., 2012-Z=0.019), and the isochrone of the Padova group (Bressan et al., 2012-Z=0.014) were used to compare each other. Of them, the Geneva models that considered stellar rotation well described the position of ${\delta}$ Cepheid variables in the blue loop. Although they were well consistent with standard period-luminosity relation of ${\delta}$ Cepheid variables, three Cepheid variables in NGC 7790 were, on average, brighter by about 0.5 mag than the absolute magnitude estimated from the mean period-luminosity relation at a given period.