• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.267-271
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• 2000

The effect of cyclodextrins on the solubility and stability of aspalatone (acetylsalicylic acid maltol ester, AM, CAS 147249-33-0), which has been recently found to have an antithrombotic effect, was investigated. The addition of ${\beta}-cyclodextrin\;({\beta}-CD),\;dimethyl-{\beta}-cyclodextrin\;(DMCD)\;or\;2-hydroxypropyl-{\beta}-cyclodextrin\;(HPCD)$ to the aqueous solution increased the solubility of AM concentration-dependently. From the phase solubility diagram, stability constants for $AM-{\beta}-CD$, -DMCD or -HPCD complexes were calculated to be 43.1, 78.3 and $53.0\;M^{-1}$. The addition of ${\beta}-CD$, DMCD or HPCD to AM solution retarded the degradation rate of AM in the acidic region. However, ${\beta}-CD$ and HPCD rather acted as an accelerator of degradation in the neutral and alkaline regions. DMCD had a stabilizing effect at all pHs studied.

• Smart Structures and Systems
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• v.29 no.6
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• pp.767-775
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• 2022

Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, produces 3D metal products by repeatedly adding and solidifying metal materials layer by layer. During the metal AM process, products experience repeated local melting and cooling using a laser or electron beam, resulting in product defects, such as warpage, cracks, and internal pores. Such defects adversely affect the final product. This paper proposes the in situ monitoring-based warpage prediction of metal AM products with experimental feature extraction. The temperature profile of the metal AM substrate during the process was experimentally collected. Time-domain features were extracted from the temperature profile, and their relationships to the warpage mechanism were investigated. The standard deviation showed a significant linear correlation with warpage. The findings from this study are expected to contribute to optimizing process parameters for metal AM warpage reduction.

• Journal of the Korean Chemical Society
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• v.40 no.8
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• pp.579-584
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• 1996

The HOMO-LUMO gap, and static and dynamic third-order polarizabilities for the polyenes are evaluated by means of the time-dependent Hartree Fock(TDHF) semiempirical PM3, AM1, MNDO, and MINDO/3 calculations. All calculations have performed on the series $C_2H_4$ to $C_{32}H_{34}$. The HOMO-LUMO gap increases in the order: MINDO/3> MNDO> PM3> AM1 levels. THG, DC-EFISHG, IDRI, and OKE for the various calculations show the order: AM1 > MNDO > PM3 levels. The various third-order effects for the polyenes have the following order: THG> DC-EFISHG> IDRI> OKE.

• Journal of the Korean Magnetics Society
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• v.18 no.2
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• pp.54-57
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• 2008

Magnetic torquer, which uses torque between magnetic dipole moment and earth magnetic field, has been used to control attitude of satellites. In this work, we developed a magnetic torquer for small scientific satellite and test under environmental conditions of the satellite launching and orbital motion have been carried out. The developed magnetic torquer shows saturation magnetic dipole moment of $15Am^2$, linearity of 0.3 % in the range of ${\pm}12Am^2$, mass of 0.46 kg, and power consumption of 1 Watt at magnetic dipole moment of $10Am^2$.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.423-428
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• 1996

The feasibility study on burning Am-241, 243 and Cm-244 nuclides in a conventional PWR (Pressurized Water Reactor) was carried out by using the TRIFON code that was developed by the Institute of Theoretical and Experimental Physics in Russia in 1992. TRIFON code uses updated ABBN Russian nuclear cross section library. The reference reactor is the Korea nuclear power plant unit 8 (YGN 2). The burning effect of Am-241, 243 and Cm-244 nuclides was studied with UO$_2$(3.5 w/o)fuel assembly and MOX (4.44 w/o) fuel assembly. The loaded mass ratio of Am-241, 243 and Cm-244 nuclides was obtained from the mass ratio of Am-241, 243 and Cm-244 nuclides in 10 year cooling spent fuel with average discharge burnup of 33 GWD/MTU. The effective transmutation rates of Am-241, 243 and Cm-244 nuclides in UO$_2$ fuel assembly were found to be higher than those in MOX fuel assembly. The result from TRIFON code was compared to that from CASMO-3/NEM-3D code system. For more reliable calculation of transmutation for MA(Minor Actinides) more sophisticated decay chain scheme of MA should be investigated and nuclear cross section library of MA should be considerably improved.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.10
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• pp.2165-2170
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• 1997

In this paepr, the distortion effects of impairments in CDMA transmitter system were analyzed. We considered not only linear distortion effects, for example, I/Q imbalance, quadrature offset and carrier leakage, but also nonlinear distortion effects such as AM-AM and AM-PM noise in power amplifier. To investigate how the impariments impact on the performance of CDMA transmitter, all effects represented as a function of CDMA modulation quality which is an important measure of the transmitted signal. These results show the limitation value of each impairment which is required to satisfy the IS-95 standard.

• Journal of the Korean Applied Science and Technology
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• v.30 no.2
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• pp.264-271
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• 2013

In this study, we have synthesized waterborne polyurethane dispersion(WPU) and analyzed mechanical properties of WPU film and leather coatings in different content of monoammonium phosphate. According to the measured data by DSC, sample WPU-AM3 which included high content of monoammonium phosphate showed the highest Tm at $382^{\circ}C$. All samples had good solvent resistance. In tensile tests, WPU-AM3($2.130kg_f/mm^2$) had the lowest physical properties. Also abrasion resistance properteis and elongation properties were investigated, WPU-AM3 had lowest physical properties with 52.07 mg.loss for abraison and 615 % of elongation.

• Korean Journal of Medicinal Crop Science
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• v.21 no.4
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• pp.262-267
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• 2013

The purpose of this study was to research for anti-oxidation and anti-wrinkle effects of Acar mono Sap (AM). To cosmetic effect of AM, safety effect (MTT assay), anti-wrinkle effect (elastase, MMP-1 inhibition assay) and anti-oxidant effect (DPPH assay) were measured. When water extract of AM was used for cell viability, it was over 100% at 6% (6 ml/100 ml in phosphate buffer) concentration. AM showed 45.7% elastase inhibition and 23.7% MMP-1 inhibition at 50% (50 ml/100 ml in phosphate buffer) concentration so that it had good anti-wrinkle characteristic. And AM showed 68.9% antioxidation capacity at 50% concentration by using a DPPH assay. Consequently, AM can be used as natural materials or additives for human skin owing to their beneficial biologic functions, including the anti-wrinkle effect, for cosmetic compositions.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.48-48
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• 2014

Arbuscular Mycorrhizal Fungi(AMF) is widespread symbiont forming mutualistic relationship with plant root in terrestrial forest in ecosystem. They provide improved absorption of nutrient and water, and enhance the resistance against plant pathogen or polluted soil, therefore AM fungi are important for survival and maintaining of individual or community of plant. For last decade, many studies about the functional variation of AM fungi on host plant growth response were showed that different geographic isolates, even same species, have different effect on host plant. However, little was known about functional variation of AM fungal isolates originated single population, which provide important insight about intraspecific diversity of AMF and their role in forest ecosystem. In this study, four AM fungal isolates of Rhizophagus clarus were cultured in vitro using transformed carrot (Daucus carota) root and they showed the difference between isolates in ontogenic characteristics such as spore density and hyphal length. The plant growth response by mycorrhizas were measured also. After 20 weeks from inoculation of these isolates to host plants, dry weight, Root:Shoot ratio, colonization rates and N, P concentration of host plant showed host plant was affected differently by AM fungal isolates. This results suggest that AM fungi have high diversity in their functionality in intraspecific level, even in same population.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.139-140
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• 2003