• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.5 s.118
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• pp.70-75
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• 2006

The purpose of this study is to explore the effects of difference in urban tree plantings on microclimate amelioration, and to suggest essential information for quantifying urban energy budgets and energy savings. This study was focused on measuring and analyzing air temperature and relative humidity in summer. Daytime air temperatures at places with 8%, 24%, 44%, 79%, and 100% cover of woody plants were, respectively, $0.6^{\circ}C,\;1.3^{\circ}C,\;2.4^{\circ}C,\;3.5^{\circ}C,\;and\;4.8^{\circ}C$ cooler, compared to a place with 0% cover. A 10% increase of woody plant cover was estimated to reduce the temperature by approximately $0.55^{\circ}C$. The temperature reduction effects were relatively greater between places with lower cover of woody plants than between those with higher cover. Woody plant cover and crown volume were the appropriate indicators which quantified the effects of tree plantings on air temperatures, based on the correlation analysis. Regression equations to estimate temperature change ($Y:^{\circ}C$) using woody plant cover ($X_1:%$) or crown volume ($X_2:m^3$) as independent variables are as follows: $$1nY=3.3233-0.0018X_1\;(r^2=0.99,\;p<0.0001)\;Y=27.5297-0.0019X_2\;(r^2=0.96,\;p=0.0007)$$

• Journal of Korean Vacuum Science & Technology
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• v.2 no.2
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• pp.107-117
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• 1998

Epitaxial undoped and Sb-doped si films have been grown on Si(001) substrates at temperatures T between 80 and 750$^{\circ}C$ using energetic Si in ultra-high-vacuum Kr+-ion-beam sputter deposition(IBSD). Critical epitaxial thicknesses te, The average thickness of epitaxial layers, in undoped films were found to range from 8nm at Ts=80$^{\circ}C$ to > 1.2 ${\mu}$m at Ts=300$^{\circ}C$ while Sb incorporation probabilities $\sigma$sb varied from unity at Ts 550$^{\circ}C$ to 0.1 at 750$^{\circ}C$. These te and $\sigma$Sb values are approximately one and one-to-three orders of magnitude, respectively, higher than reported results achieved with molecular-beam epitaxy. Plan-view and cross-sectional transmission electron microscopy, high-resolution x-ray diffraction, channeling and axial angular-yield profiles by Rutherford back scattering spectroscopy for epitaxial Si1-x Gex(001) alloy films (0.15$\leq$x$\leq$0.30) demonstrated that the films are of extremely high crystalline quality. critical layer thicknesses hc the film thickness where strain relaxation starts, I these alloys wre found to increase rapidly with decreasing growth temperature. For Si0.70 Ge0.30, hc ranged from 35nm at Ts=550$^{\circ}C$ to 650nm at 350$^{\circ}C$ compared to an equilibrium value of 8nm.

• Journal of Life Science
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• v.22 no.3
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• pp.306-311
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• 2012

A gene encoding a lipase, lipT, was cloned from the psychrotrophic bacterium Pseudomonas mandelii and sequenced. An open reading frame of 1,686 bp was found that encodes a polypeptide consisting of 562 amino acid residues. Sequence analysis revealed a Gly-His-Ser-Leu-Gly sequence, which matches the consensus Gly-X-Ser-X-Gly motif conserved among lipolytic enzymes. The recombinant LipT protein was predominantly expressed as inclusion bodies in Escherichia coli and subsequently purified by nickel-chelate affinity chromatography. A small fraction of LipT was refolded, and the subsequent LipT exhibited substrate preferences for p-nitrophenyl butyrate (C4) and p-nitrophenyl octanoate (C8).

• Bulletin of the Korean Chemical Society
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• v.19 no.8
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• pp.847-851
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• 1998

13C, 15N, and 29Si NMR chemical shifts have been computed for selected X-substituted silatranes (X=Cl, F, H, CH3) using Gauge-Including Atomic Orbitals (GIAO) and Continuous Set of Gauge Transformations (CSGT) at the Hartree-Fock level of theory. The isotropic 13C chemical shifts are largely insensitive to substituent-induced structural changes. In this study, the isotropic 13C chemical shifts GIAO and CSGT calculations at the HF/6-31G and HF/6-31G* levels are sufficiently accurate to aid in experimental peak assignments. The isotropic 13C chemical shifts X-substituted silatranes at HF/6-31G* level are approximately 4 ppm different from the experimental values. In contrast, the isotropic 15N and 29Si chemical shifts and the chemical shielding tensors are quite sensitive to substituent-induced structural changes. These trends are consistent with those of the experiment. The 15N chemical shift parameters demonstrate a very clear correlation with Si-N distance, especially when we use the polarization function. Changes in anisotropy, 3a as well as in the 15N isotropic chemical shifts are due primarily to changes in the value of a.. But in case of "Si the correlations are not as clean as for the 15N chemical shift.

• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.398-403
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• 1987

A general theory of polymer adsorption at a semi-permeable oil-water interface of the biphasic solution is presented. The configurational factor of the solution in the presence of the semi-open boundary at the interface is evaluated by the quasicrystalline lattice model. The present theory gives the feature of the bulk concentration equilibria between oil-water subsystems and the surface excesses of ${\Gamma}^{\alpha}$ and ${\Gamma}^\{beta}$ of the polymer segments as a function of the degree of polymerization $\gamma$, the Flory-Huggins parameter in $\beta$-phase $x_{\rho}^{{\beta}_{\rho}}$, the differential adsorption energy parameter in $\beta$-phase $x_{\sigma}^{{\beta}_{\rho}}$, the differential interaction energy parameter ${\Delta}x_{\rho}$ and the bulk concentration of the polymer in ${\beta}-phase ${\varphi}_2^{{\beta(*)}_2}$. From our numerical results, the characteristics of ${\Gamma}^{\alpha}$ are shown to be significantly different from those of ${\Gamma}^{\beta}$ in the case of high polymers, and this would be the most apparent feature of the adsorption behavior of the polymer at a semi-permeable oil-water interface, which is sensitively dependent on ${\Delta}x_{\rho}$ and r.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1053-1058
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• 2021

This paper presents the multi-band mixer which converts a X-, K- and Ka-band adaptively by adjusting the gate-bias voltage of an active device. The proposed mixer presented a conversion loss of -10 dB at -0.8 V gate-bias voltage for X-band, a conversion loss of -9 dB at -0.3 V gate-bias voltage for K-band and for Ka-band, a conversion loss of -7 dB at -0.2 V gate-bias voltage under the LO power of +6.0 dBm. The 1dB compression point (P1dB) is +0.5 dBm for all band.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.05a
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• pp.8.1-8.1
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• 2006

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.961-964
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• 1999

• Journal of Chest Surgery
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• v.24 no.9
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• pp.837-842
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• 1991

Calcification is a major problem in glutaraldehyde-preserved bioprosthetic valves. We have used bovine pericardium processed in a solution containing 0.625% glutaraldehyde, 0.05M HEPES buffer and 0.26% magnesium chloride in saline. And, we also treated the glutaraldehyde-preserved bovine pericardium with a surfactant, Triton X - 100 to reduce calcification. To evaluate the degree of calcification. 4 kinds of pericardial xenografts, group I [Xenomedica, equine pericardial xenografts], group II [0.625% glutaraldehyde-preserved bovine pericardiums], group III [0.5% Triton X - 100 treated bovine pericardiums], and group IV [1.2% Triton X - 100 treated bovine pericardiums] were implanted in subcutaneous layer of growing rabbits, and they were explanted about 3 months later. The mean calcium contents[%/mg of dry tissue] of 0.5% and 1.2% Triton X - 100 treated bovine pericardiums [80.0$\pm$27.1%: 78.6$\pm$47.0% respectively] were lower than those of glutaraldehyde-preserved bovine pericardiums[126.2$\pm$29.8] [p=0.05]. Thus, under the conditions of subcutaneous implantation in rabbits, Triton X - 100 was efficient in calcification mitigation.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.8 no.1
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• pp.11-15
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• 1978

The author observed the effect of x-ray irradiation on the development of the mandible in the fetuses and growing albino rats. The fetuses were irradiated on the 7½th day of gestation, 100, 200, 300, and 400 rads of x-ray respectively. The experimental animals were sacrificed on the 18½th day of gestation, and first week, second week and third week after parturition. The results were as follows; 1. The mandible of the 18½th day fetuses showed irregular bone trabeoulae, osteoclasts and osteocyte degeneration on the 300 and 400 rads x-ray irradiated fetuses. 2. In the mandible of the first week rats, there was marked osteocyte degeneration and a lot of osteoclast. 3. In the mandible of the 2nd and 3rd week rats bone remodeling was evident. The 3rd week rats also showed alteration of blood vessel wall.