• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.2
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• pp.164-172
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• 2001

The angiotensin-I converting enzyme (ACE) inhibitors from laver hydrolysate was isolated. Among the 13 kinds of proteases, Maxazyme NNP was most effective for preparing the high ACE inhibitory compound. In extraction conditions of ACE inhibitory peptide from laver hydrolysate, ACE inhibitory activity of hydrolysate treated with diethylether for decolorization and that of $70\%$ ethanol soluble fraction among the different ethanol concentrations were higher than other preparations. Low molecular fraction less than 3,000 dalton of layer hydrolysate separated by ultrafiltration had the highest ACE inhibitory activity, for further separation of ACE inhibitory peptide from laver hydrolysate, gel filtration chromatography (Sephadex G-25), reverse-phase HPLC (ODS & Vydac C-18) and gel permeation chromatography (Superdex Peptide HR) were performed. The molecular mass of the ACE inhibitory peptide fractions of gel permeation chromatography determined by electrospray-mass spectrometer were 413.48 (S1O2V2V1P),346.86 (S1O2V2V2P) and 320.32 (S2O6V3V1P) dalton and their amino acid sequence were Val-Gln-Gly-Asn, Thr-Glu-Thr and Phe-Arg, respectively.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.11a
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• pp.917-920
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• 2011

VANET은 V2V, V2I 통신을 통해 다양한 서비스를 제공하며, 차량은 여러 가지 서비스를 제공받아 안전하고 효율적인 운행을 할 수 있다. 다양한 서비스를 제공하고 이용하기 위해 안전하고 신뢰성 있는 V2V, V2I 통신이 보장되어야 하며, 이를 위해 많은 연구들이 진행되었다. 기존의 대부분의 연구들은 공개키 기반 암호시스템을 이용하였다. 하지만 VANET의 DSRC 프로토콜에 의하면 한 차량에서 짧은 순간에 매우 많은 메시지를 확인해야 하며, 따라서 매우 큰 연산량이 발생하게 된다. 또한 DSRC를 사용할 경우 서버와의 통신을 항상 보장할 수 없다. 본 논문에서는 이를 해결하기 위해 다른 통신 메커니즘의 사용을 고려한 대칭키 기반 인증 프로토콜을 제안한다.

• Bulletin of the Korean Mathematical Society
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• v.49 no.4
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• pp.715-736
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• 2012

Brown provided a structure theorem for a class of perfect ideals of grade 3 with type ${\lambda}$ > 0. We introduced a skew-symmetrizable matrix to describe a structure theorem for complete intersections of grade 4 in a Noetherian local ring. We construct a class of perfect ideals I of grade 3 with type 2 defined by a certain skew-symmetrizable matrix. We present the Hilbert function of the standard $k$-algebras R/I, where R is the polynomial ring $R=k[v_0,v_1,{\ldots},v_m]$ over a field $k$ with indeterminates $v_i$ and deg $v_i=1$.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.1-18
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• 2007

Non-linear elastic wavefield inversion is a powerful method for estimating elastic parameters for physical constraints that determine subsurface rock and properties. Here, I introduce six elastic-wave velocity models by reconstructing elastic-wave velocity variations from real data and a 2D elastic-wave velocity model. Reflection seismic data information is often decoupled into short and long wavelength components. The local search method has difficulty in estimating the longer wavelength velocity if the starting model is far from the true model, and source frequencies are then changed from lower to higher bands (as in the 'frequency-cascade scheme') to estimate model elastic parameters. Elastic parameters are inverted at each inversion step ('simultaneous mode') with a starting model of linear P- and S-wave velocity trends with depth. Elastic parameters are also derived by inversion in three other modes - using a P- and S-wave velocity basis $('V_P\;V_S\;mode')$; P-impedance and Poisson's ratio basis $('I_P\;Poisson\;mode')$; and P- and S-impedance $('I_P\;I_S\;mode')$. Density values are updated at each elastic inversion step under three assumptions in each mode. By evaluating the accuracy of the inversion for each parameter set for elastic models, it can be concluded that there is no specific difference between the inversion results for the $V_P\;V_S$ mode and the $I_P$ Poisson mode. The same conclusion is expected for the $I_P\;I_S$ mode, too. This gives us a sound basis for full wavelength elastic wavefield inversion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.11a
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• pp.141-143
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• 1993

A nontoxic organic photoreceptor for near infrared light has been developed. A double layered photoreceptor using $\tau$-H$_2$Pc as the CGL was made. The CTL was formed by oxadiazole derivative dispersed in two other host polymers. This photoreceptor has a charge acceptance of -900 V when a corona charge is used, and has residual potentials of -20 V for PC, and -10 V for PVB by light irradiation.

• The Pure and Applied Mathematics
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• v.4 no.2
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• pp.115-119
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• 1997

We show that if $f_{i}$:$X_{i}$ longrightarrow Y is strongly continuous(resp. weakly continuous, set connected, compact, feebly continuous, almost-continuous, strongly $\theta$-continuous, $\theta$-continuous, g-continuous, V-map), then F : $X_1 \bigoplus X_2$longrightarrow Y is strongly continuous(resp.weakly continuous, set connected, compact, feebly continuous, almost-continuous, strongly $\theta$-continuous, $\theta$-continuous, g-continuous, V-map).

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.97-97
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• 2001

This Study was attempted to investigate tile effect of dopamine, SKF 81297, a dopamine D$_1$-receptor agonist, and TNPA, a dopamine D$_2$-receptor agonist, on the blood pressure in rat. Dopamine exhibited the hypertensive action in proportion to the doses of 1.0, 3.0 arid 10.0 $\mu\textrm{g}$/kg i.v., these hypertensive action of dopamine was blocked significantly by SCH 23390, a dopamine D$_1$-receptor antagonist, on the other hand, more potentiated by raclopride, a dopamine D$_1$-receptor antagonist. SKF 81297 produced hypertensive action in a dose of 1.0 $\mu\textrm{g}$/kg i.v., wherease hypotensive action in proportion to administered doses 3.0 and 10.0 $\mu\textrm{g}$/kg i.v., these hypertensive action of SKF 81297 in a dose of 1.0 $\mu\textrm{g}$/kg i.v. was not influenced by SCH 23390 or raclopride, but hypotensive action of SKF 81297 in tile doses of 3.0 and 10.0 $\mu\textrm{g}$/kg i.v. was weakened significantly by SCH 23390, but more strenthened by raclopride. TNPA showed the hypotensive action in inverse proportion to administered doses of 1.0, 3.0 and 10.0 $\mu\textrm{g}$/kg i.v., these hypotensive action was reversed to hypertensive action in inverse proportion to the administered doses of TNPA by SCH 23390 and raclopride.

• Proceedings of the Materials Research Society of Korea Conference
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• 2004.05a
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• pp.87-87
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• 2004

• Journal of the Korean Society of Radiology
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• v.4 no.2
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• pp.27-30
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• 2010

A X-ray optical modulator measures x-ray dose using optical transmissivity ratio change of the liquid crystal cell. To apply in this optical modulator, we made photoconductor films and compared electrical properties of this films in this study. Photoconductors are deposited on ITO glass with $200{\mu}m$ using the percipitation method and print method. I-V test was conducted to alalyze electrical properties of this films and measured darkcurrent and SNR was acquired using the measured dark current and sensitivity. As a result of this measurements, $HgI_2$ film made by precipitation method is lower(about 40%) darkcurrent than $HgI_2$ films made by precipitation method and sensitivity is two times greater than print method. And we knew that $HgI_2$ films were also 10~25 times greater SNR at $1v/{\mu}m$ than $PbI_2$, PbO, CdTe film made by precipitation method. This results suggest that $HgI_2$ films made by precipitation method has improved characteristics of x-ray dose meter by applying in x-ray optical modulator.

• Journal of Korean Society for Atmospheric Environment
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• v.8 no.1
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• pp.58-67
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• 1992

For removing $NO_x$ and $SO_x$ from the flue gases emitted from stationary sources, $V_2O_5-MoO_3/TiO_2$ catalysts were prepared by the conventional impregnation method (aqueous solution) and a sort of surface fixation method(nonaqueous solution) as reported excellent reproducibility catalysts. And these catalysts observed their catalytic activities as well as their surface properties. V-Mo-O oxide, prepared from nonaqueous solution of $VOCl_3$ and $Mo(CO)_6$ and aqeous solution method, was supported as amorphous state by XRD and SEM measurements. The infrared spectra of fresh and used catalysts showed that in used catalysts, V=O bands decreased and new bands of vanadium oxysulfate bands were very sensitive. So the catalysts prepared from nonaqueous solution may bring about the high activity. Results from catalytic activity measurements at 350$^\circ$C, in the presence of $SO_2, NO$ conversion was more increased than in absence of $SO_2$. As the $MoO_3$ was added to $V_2O_5/TiO_2 system, SO_2$ conversion increased. It found that from the results, $V_2O-5-MoO_3/TiO_2$ catalysts prepared from an nonaqueous solution may bring about the high activity for both the reaction of NO and $SO_2$ removal.