• Journal of Astronomy and Space Sciences
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• v.32 no.4
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• pp.327-333
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• 2015

Previously, all-sky airglow images observed at Shigaraki ($34.9^{\circ}N$, $136.1^{\circ}E$), Japan, during 2004 and 2005 were analyzed in relation to those observed at Mt. Bohyun ($36.2^{\circ}N$, $128.9^{\circ}E$) for a comparison of their gravity wave characteristics (Kim et al. 2010). By applying the same selection criteria of waves and cloud coverages as in the case of Mt. Bohyun all-sky images, we derived apparent wavelengths, periods, phase velocities, and monthly occurrence rates of gravity waves at Shigaraki in this study. The distributions of wavelengths, periods, and speeds derived for Shigaraki were found to be roughly similar to those for Mt. Bohyun. However, the overall occurrence rates of gravity waves at Shigaraki were 36% and 34% for OI 557.7 nm and OH Meinel band airglow layers, respectively, which were significantly higher than those at Mt. Bohyun. The monthly occurrence rates did not show minima near equinox months, unlike those for Mt. Bohyun. Furthermore, the seasonal preferential directions that were clearly apparent for Mt. Bohyun were not seen in the wave propagation trends for Shigaraki. These differences between the two sites imply different origins of the gravity waves near the Korean peninsula and the Japanese islands. The gravity waves over the Japanese islands may originate from sources at various altitudes; therefore, wind filtering may not be effective in causing any seasonal preferential directions in the waves in the airglow layers. Our analysis of the Shigaraki data supports recent theoretical studies, according to which gravity waves can be generated from in situ sources, such as mesosphere wind shear or secondary wave formation, in the mesosphere.

• The Korean Journal of Physiology
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• v.21 no.2
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• pp.157-167
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• 1987

Benzyl alcohol is known to have dual effect on the red blood cell shape change. At low concentration up to 50 mM benzyl alcohol transformed the shape from discocyte to stomatocyte by preferent binding to the inner hemileaflet, however, at higher concentratransformed the shape from discocyte to stomatocyte by preferential binding to the inner monolayer, however, at higher concentration above 50 mM benzyl alcohol transformed to echinocyte by affecting both monolayers. These results suggest that the effect of benzyl alcohol on the red blood cell shape and $Ca^{++}$ transport across cardiac cell membranes to assess the effects of the drug on the structures and functions of the biological cell membranes. The results are as follows: 1) Benzyl alcohol up to 40 mM caused progressive stomatocytic shap change of the red blood cell but above 50 mM benzyl alcohol caused echinocytic shape change. 2) Benzyl alcohol up to 40 mM inhibited both osmotic hemolysis and osmotic volume change of the red blood cell in hypotonic and hypertonic NaCl solutions, respectively. 3) Benzyl alcohol inhibited both Bowditch Staircase and Wood-worth Staircase phenomena at rat left auricle. 4) Benzyl alcohol at concentration of 5 mM increased $Ca^{++}-ATPase$ activity of red blood cell ghosts slightly but above S mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. 5) Benzyl alcohol at concentrations of 5 mM and 10 mM increased $Ca^{++}-ATPase$ activity slightly at rat gastrocnemius muscle S.R. but above 10 mM benzyl alcohol inhibited the $Ca^{++}-ATPase$ activity. Above results indicate that benzyl alcohol inhibit water permeability and $Ca^{++}$ transport across cell membranes in part via effects on the fluidity and transition temperatures of the bulk lipid by preferential intercalation into cytoplasmic monolayer and in part via other effect on the conformational change of active sites of the $Ca^{++}-ATPase$ molecule extended in cytoplasmic face.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.255-263
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• 2012

BACKGROUND: The analysis for the concentration and enantiomeric ratio of OCPs have been performed to confirm the distribution and to emonstrate the pollution characteristics of chiral OCPs in ambient air. METHODS AND RESULTS: In ambient air at coastal and inland sites, concentrations and enantiomer fractions (EFs) of heptachlor (HEPT), eptachlor epoxide (HEPX), trans-chlordane (TC), cis-chlordane (CC), xychlordane (OXY), 2,4'-DDT, 2,4'-DDD with HRGC/HRMS were investigated to understand source and distribution of chiral organochlorine pesticides (OCPs) in ambient air. The mean concentrations of OCPs in ambient air were at the range of 0.027(heptachlor)~1.279 (4,4'-DDT) pg/m3 and 0.0005 (heptachlor)~0.1043 ng/g d.w. (TC), respectively. The mean EFs of OCPs in ambient air were at the range of 0.73 (HEPX)~0.45 (CC). Both preferential depletions of (+) and (-) enantiomer were observed for CC, indicated by EFs either <0.5 or >0.5, while preferential depletions of (-) enantiomer which mean EFs <0.5 were observed for chiral OCPs except TC and MC-5. CONCLUSION: OCPs in ambient air have been distributed from soil, but some of them such as chlordane, DDT etc. might have been introduced by long-range atmospheric transport, considering EFs by chiral analysis and trajectory analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1507-1510
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• 2005

This study was carried out as a part of the research on the development of a maskless and electroless process for fabricating metal micro/nanostructures by using a nanoindenter and an electroless deposition technique. $2-\mu{m}-deep$ indentation tests on Ni and Cu samples were performed. The elastic recovery of the Ni and Cu was 9.30% and 9.53% of the maximum penetration depth, respectively. The hardness and the elastic modulus were 1.56 GPa and 120 GPa for Ni and 1.49 GPa and 100 GPa for Cu. The effect of single-point diamond machining conditions such as the Berkovich tip orientation (0, 45, and $90^{\circ}$) and the normal load (0.1, 0.3, 0.5, 1, 3, and 5 mN), on both the deformation behavior and the morphology of cutting traces (such as width and depth) was investigated by constant-load scratch tests. The tip orientation had a significant influence on the coefficient of friction, which varied from 0.52-0.66 for Ni and from 0.46-0.61 for Cu. The crisscross-pattern sample showed that the tip orientation strongly affects the surface quality of the machined area during scratching. A selective deposition of Cu at the pit-like defect on a p-type Si(111) surface was also investigated. Preferential deposition of the Cu occurred at the surface defect sites of silicon wafers, indicating that those defect sites act as active sites for the deposition reaction. The shape of the Cu-deposited area was almost the same as that of the residual stress field.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.171-177
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• 2006

This study was performed as a part of the research on the development of a maskless and electroless process for fabricating metal micro/nanostructures by using a nanoindenter and an electroless deposition technique. $2-{\mu}m$-deep indentation tests on Ni and Cu samples were performed. The elastic recovery of the Ni and Cu was 9.30% and 9.53% of the maximum penetration depth, respectively. The hardness and the elastic modulus were 1.56 GPa and 120 GPa for Ni and 1.51 GPa and 104 GPa for Cu. The effect of single-point diamond machining conditions such as the Berkovich tip orientation (0, 45, and $90^{\circ}$ ) and the normal load (0.1, 0.3, 0.5, 1, 3, and 5 mN), on both the deformation behavior and the morphology of cutting traces (such as width and depth) was investigated by constant-load scratch tests. The tip orientation had a significant influence on the coefficient of friction, which varied from 0.52-0.66 for Ni and from 0.46- 0.61 for Cu. The crisscross-pattern sample showed that the tip orientation strongly affects the surface quality of the machined are a during scratching. A selective deposition of Cu at the pit-like defect on a p-type Si(111) surface was also investigated. Preferential deposition of the Cu occurred at the surface defect sites of silicon wafers, indicating that those defect sites act as active sites for the deposition reaction. The shape of the Cu-deposited area was almost the same as that of the residual stress field.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.383-393
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• 2020

The purpose of this study is to investigate the condition of the production facilities of severely impaired products for two years from 2017 to 2018, and to suggest ways to improve the preferential purchase system for the severely disabled comparison with previous study. As of June 2018, 267 out of 544 sites were research and analyzed. As a result, first, the average number of severely disabled workers is 16.51, and the total number of workers, disabled workers who participated in direct production, and non-disabled workers showed the trend of increase in 2018. Second, the average monthly wage of workers with disabilities participating in direct production increased slightly from 790,977 won in 2017 to 829,810 won in 2018. Third, Analysis of changes in sales of production facilities before and after designations showed that overall sales of production facilities increased after designations and after designations. Improvement measures include preferential purchase rate improvement and support for production facilities and purchasing public institutions, classification of roles of performance organizations, Clarification of the role of priority purchasing promotion committee for products produced by people with severe disabilities, complementing the minimum wage exclusion system.

• The Journal of Engineering Geology
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• v.3 no.3
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• pp.241-252
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• 1993

Lead bas been found in the groundwater in Door County, Wiscorsin, with temporally and spatially irregular distribution in concentration. Correlation coeffidents were calculated among lead indicators in groundwater(frequency of lead detections, mean and maximum concentration of lead detections) and seven independent variables(stucture and geographic factors of wells, hydrogeological factors at lead-arsenate mixing sites and the level of soil contamination) which are possibly related to the lead level in groundwater. The significance of relationships was determined statistically by a t-test at the 90% confidence level, and indicated that the spatially located lead-arsenate mixing sites provided the lead in groundwater in the study area. A total of 112 groundwater samples were collected from 5 house wells with previous lead detects. Lead was detected in partides on ifiter papers with $0.45{\;}\mu\textrm{m}$ pore size, but not in filtrates. The result of chemical analysis for lead indicates that lead is associated with partides in groundwater in Door County. Subsequently, the irregular distribution of lead in the county results from the transport of particulate lead along the advective groundwater movement through the preferential pathways sucn as vertical and bedding-plane joints.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.12
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• pp.2395-2400
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• 2016

Conventional drug carriers such as liposomes, nanoparticles, polymer micelles, polymeric conjugate and lipid microemulsion for cancer chemotherapy shield normal tissues from toxic drugs to treat cancer cells in tumors. However, inaccurate tumor targeting uncontrolled drug release from the carriers and unwanted accumulation in healthy sites can limit treatment efficacy with current conventional drug carriers with insufficient concentrations of drugs in the tumors and unexpected side effects as a result. Sickle red blood cells show natural tumor preferential accumulation without any manipulation due to the adhesive interaction between molecular receptors on the membrane surface and counter-receptor on endothelial cells. In addition, structural changes of microvascular in tumor sites enhances polymerization of sickle red blood cells. In this research, we examined the use of sickle red blood cells as a new drug carrier with novel tumor targeting and controlled release properties to quantify its therapeutic effects.

• Journal of the Mineralogical Society of Korea
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• v.9 no.2
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• pp.55-63
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• 1996

Epidote occurs as veinlets in the propylitic alteration zone of the Bobae clay deposit, Pusan, Korea. Its cell parameters apparently decrease with the contents of Al, Fe, and Ca. Fourier transform infrared (FTIR) spectra show one hydrosyl environment related to AlM2 at 3357-3358 cm-1. In the mid-infrared region, the peaks at 950 and 1030 cm-1 sharper with increasing Al shifting to higher energy region. The peak at 885 cm-1 shifts slightly to a lower energy region with a decreasing intensity as the Fe content increases. In the far-IR region, epidote exhibits absorption bands at 120 and 140 cm-1, which are related to the Ca-O bonds in A-sites.M ssbauer spectra of epidote show that the isomer shifts of Fe3+ range from 0.36-0.37 at the M3 site and from 0.35-0.44 at M1 site. Fe2+ shows the isomer shift ranging from 1.11 to 1.13. Quadrupole splitting is 2.04 for Fe3+M3, 0.52-0.70 for Fe3+M1, and 2.61-2.70 for Fe2+M3. Calculation shows Fe3+M386-90.7%, Fe3+M12.5-3.6%, and Fe2+M35.8-11.4% of total iron, showing preferential distribution of Fe3+ in the M3 site. The Fe3+M3 content is between 0.486 and 0.513 per formula unit. in the Fe-rich epidote, less Fe3+ and more Fe2+ are accommodated in the M1 and M3 sites. Hence, the overall disorder increases as total Fe content increase. The ordering parameter of the Bobae epidote is 0.93-0.95, suggesting a disequilibrium state below 200$^{\circ}C$. The constant temperature over a long period may be essential for the transition from disordered state to equilibrium state, despite the possible variation in flux and composition of the hydrothermal fluid.

• Journal of the Korean Society for Heat Treatment
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• v.14 no.2
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• pp.89-95
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• 2001

The 7175Al alloy is particularly interesting for its high strength and sufficient ductility, fracture toughness and corrosion resistance. Currently vigorous efforts have been made to develop large rockets usable for various purposes in the space. This has created the demand of big size of 7175Al billet which would be applied to heavy forgings. The aim of this study is to investigate the quality level of big billet and the effect of billet size on the mechanical properties of large 7175Al ring roll forgings. The billets range from 370 mm to 720 mm in diameter were homogenized and forged after direct chill casting. The size and volume fraction of second phase particles In ${\Phi}720$ mm billet are larger than those of ${\Phi}370$ mm billet, and its ductility is lower for the condition of homogenization and T6 treatment. The Cu-rich phases formed in interdendritic sites are considered to provide the preferential crack path during cold upsetting. The fracture toughness of ring roll forgings which are made by ${\Phi}370$ mm billet is higher than those of ${\Phi}720$ mm billet.