• International journal of advanced smart convergence
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• v.5 no.3
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• pp.27-31
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• 2016

High-tech industries in a state well enough to troubleshoot hacking information introduction a big barrier to delay the growth of the market related to IoT(Internet of Things) as is likely to be on the rise. This early on, security issues introduced in the solution, a comprehensive solution, including the institutional laws/precautions needed. Recent examples of frequent security threats while IoT is the biggest issue of introducing state-of-the-art industry information due to the vulnerable security hacking. This high-tech industries in order to bridge the information responsible for the target attribute, target range, and the protection of security and how to protect the subject, IoT environment (domestic industrial environment) considering the approach is needed. IoTs with health care and a wide variety of services, such as wearable devices emerge. This ensures that RFID/USN-based P2P/P2M/M2M connection is the implementation of the community. In this study, the issue on the high-tech industrial information and the vulnerable security issues of IoT are described.

• 한국포장학회:학술대회논문집
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• 2006.11a
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• pp.54-73
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• 2006

Four different types of chitosan-based nanocomposite films were prepared using a solvent casting method by incorporating with four types of nanoparticles, i.e., an unmodified montmorillonite (Na-MMT), an organically modified montmorillonite (Cloisite 30B), a Nano-silver, and a Ag-zeolite (Ag-Ion). X-ray diffraction patterns of the nanocomposite films indicated that a certain degree of intercalation was formed in the nanocomposite films, with the highest intercalation in the Na-MMT-incorporated films followed by films with Cloisite 30B and Ag-Ion. SEM micrographs showed that in all the nanocomposite films, except the Nanosilver-incorporated one, nanoparticles were dispersed homogeneously throughout the chitosan polymer matrix. Consequently, mechanical and barrier properties of chitosan films were affected through intercalation of nanoparticles, i.e., tensile strength (TS) increased by 7-16%, while water vapor permeability (WVP) decreased by 25-30% depending on the nanoparticle material tested. In addition, chitosan-based nanocomposite films, especially silver-containing ones, showed a promising range of antimicrobial activity.

• Journal of the Korean Chemical Society
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• v.65 no.6
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• pp.419-432
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• 2021

According to the transition state (TS) theory, Gaussian software and Yao and Lin (YL) method, the thermodynamics and kinetic data respectively were calculated, and anharmonic effect was considered for related reactions of NO₃. The methods of calculating and fitting kinetic and thermodynamics parameters were provided by least square method and related equations in this paper. Notably, the fitted E of Arrhenius equation was close to the calculated barrier of related reaction by QCISD(T) method. Therefore, the kinetic fitting result can well express the physical meaning of E in Arrhenius equation. Besides, the conversion process and the reaction mechanism of NO₃ were researched. For NO₃, it seemed that its instability results from its easy reaction with other substances rather than the decompose reaction of itself.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1149-1156
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• 2008

The conformational study on neutral and zwitterionic L-alanines (N-Ala and Z-Ala, respectively) and the transition state (TS) for their interconversion is carried out using ab initio HF and density functional B3LYP methods with the self-consistent reaction field method in the gas phase and in solution. At both the HF and B3LYP levels of theory, the local minimum N1 for N-Ala is found to be most preferred in the gas phase and a weak asymmetric bifurcated hydrogen bond between the amino hydrogens and the carbonyl oxygen appears to play a role in stabilizing this conformation. The local minima N2a and N2b are found to be the second preferred conformations, which seem to be stabilized by a hydrogen bond between the amino nitrogen and the carboxylic hydrogen. The relative stability of the local minimum N2b is remarkably increased in solution than that in the gas phase. The local minimum N2b becomes more stable than the local minimum N2a in most of the solution. On the whole the relative free energies of Z-Ala and TS become more lowered, as the solvent polarity increases. N-Ala prevails over Z-Ala in aprotic solutions but Z-Ala is dominantly populated in ethanol and water. In aprotic solutions, the population of Z-Ala increases somewhat with the increase of solvent polarity. The barrier to Z-Ala-to-N-Ala interconversion increases on the whole with the increase of solvent polarity, which is caused by the increase of stability for Z-Ala.

• Progress in Superconductivity and Cryogenics
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• v.6 no.3
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• pp.27-32
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• 2004

High temperature superconducting coated conductor has a structure of /< superconducting layer>//. The buffer layer consists of multi layer, and the architecture most widely used in RABiTS approach is CeO$_2$(cap layer)/YSZ(diffusion barrier layer)/CeO$_2$(seed layer). Evaporation technique is used for the CeO$_2$ layer and DC reactive sputtering technique is used for the YSZ layer, A chamber was set up specially for DC reactive sputtering, Detailed features are as following. A separator divided the chamber into two halves a sputtering chamber and a reaction chamber. The argon gas for sputtering target elements flows out of the cap of sputtering gun, and water vapor for reaction with depositing species spouts near the substrate. Turbo pump is connected with reaction chamber. High speed deposition of YSZ film could be achieved in the chamber. Detailed deposition conditions (temperature and partial pressure of reaction gas) were investigated for the rapid growth of high quality YSZ film.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.180-181
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• 2006

As a rule, high temperature superconducting coated conductors have multi-layered buffers consisting of seed, diffusion barrier and cap layers. Multi-buffer layer deposition requires longer fabrication time. This is one of main reasons which increases fabrication cost Thus, single buffer layer deposition seems to be important for practical coated conductor process. In this study, a single layered buffer deposition of $CeO_2$ for low cost coated conductors has been tried using thermal evaporation technique 100nm-thick $CeO_2$ layers deposited by thermal evaporation were found to act as a diffusion layer. $0.4{\mu}m$-thick SmBCO superconducting layers were deposited by thermal co-evaporation on the $CeO_2$ buffered Ni-W substrate. Critical current of 118A/$cm^2$ was obtained for the SmBCO coated conductors.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.240-241
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• 2007

In general, high temperature superconducting coated conductors have intermediary buffers layer consisting of seed, diffusion barrier and cap layers. Simplification of the oxide materials buffer architecture in the fabrication of high temperature superconducting coated conductors is required because the deposition of multi-layers buffer architecture leads to a longer manufacturing time and a higher cost process of coated conductors. Thus, single buffer layer deposition seems to be important for practical coated conductor manufacturing process. In this study, a single gradient layered buffer deposition process of YZO for low cost coated conductors has been tried using DC reactive sputtering technique. About several thick YZO gradient single buffer layers deposited by DC co-sputtering process were found to act as a diffusion layer.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.113-116
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• 2003

Color value, total color difference $({\triangle}E)$, puncture strength (PS), tensile strength (TS), percent elongation(%E) at break values, and water vapor permeability (WVP) were determined for water-soluble chitosan films added with soy protein isolate (SPI) and $CaCl_2$. Mechanical and water vapor barrier properties of the chitosan films were affected by SPI and $CaCl_2$ concentrations. PS value $(174.5-448.8\;g_f)$ of the chitosan films increased with increasing concentration of $CaCl_2$ TS value of 0.05% $CaCl_2$-added chitosan films significantly increased to 1.58 MPa compared to 0.06 MPa of the control. %E values ranged from 12.25 to 44.80% and increased with increasing concentration of $CaCl_2$. WVP of $CaCl_2$-added films was lower than that of SPI-added films.

• Food Science and Preservation
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• v.13 no.3
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• pp.285-291
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• 2006

The effects of sorbitol mixture as plasticizers on moisture sorption property (MSP), water vapor permeability (WVP), color, tensile strength (TS), elongation at break (E), and total soluble matter (TSM) of soy protein isolate (SPI) films were investigated. Two different types of sorbitols, aqueous and crystalline, were added to film-forming solutions in various ratios of crystalline to aqueous (0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25, or 1:0, based on weight). In addition, the characteristics of the SPI films plasticized by sorbitol mixtures and glycerin were compared with moisture sorption rate against time. Sorbitol-plasticized films had higher in TS, but lower in WVP and E than the glycerin-plasticized films. However the properties of SPI films did not differ appreciably by the type of sorbitol added to film-forming solutions. To explain the high solubility and low WVP of sorbitol-plasticized films, cumulative amounts of moisture content gained during adsorption and lost during desorption of films were compared between sorbitol and glycerin-plasticized films. The result suggest that use of sorbitol as a plasticizer for preparing SPI films improves moisture barrier properties of the films. However the high solubility of sorbitol-plasticized films needs to be reduced for improving the functionality of SPI films in potential packaging applications.

• Food Science and Preservation
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• v.31 no.1
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• pp.126-137
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• 2024

In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using three distinct zinc salts: zinc acetate, zinc chloride, and zinc nitrate. These ZnONPs were subsequently utilized in the fabrication of carrageenan-ZnONPs (Car-ZnONPs) composite films. The study assessed influence of the various ZnONPs on the morphological, water vapor barrier, color, optical, and antimicrobial properties of the Car-ZnONPs composite films. The surface morphology and UV-blocking attributes of the composite films were affected by the type of ZnONPs used, but their surface color, transparency, and chemical structure remained unaltered. The composite film's thickness and elongation at break (EB) significantly increased, while the tensile strength significantly decreased. In contrast, film's elastic modulus (EM) and water vapor permeability coefficient (WVP) showed no significant difference. All the composite films with added ZnONPs demonstrated potent antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes . Among the carrageenan-based composite films, Car-ZnONPs^ZC showed the highest antibacterial and UV-blocking properties, and its elongation at break was significantly higher than that of the pure carrageenan films. This suggests that ZnONPs composite films have the potential to be used as an active packaging film, preserve the safety of the packaged food and extend shelf life.