• The Korean Journal of Ceramics
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• v.6 no.3
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• pp.280-285
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• 2000

The electrolyte, $(HO)_2C_6H_2(SO_3Na)_2H_2O $(Tiron), disperses efficiently alumina powder in aqueous media and stable suspensions with 60 vol% solid loading can be prepared. The strong adsorption of this additive is mainly due to the ability of the molecule to form chelate rings with the particle surface but electrostatic interactions between the surface charge and the anionic dispersant strongly influence the amount of Tiron adsorbed. By using a cationic exchange route to substitute the counter ion which neutralizes the sulfonate groups, new molecules of dispersant have been prepared, either with mineral cations as $Li^+,\; Na+^,\; NH_4^\;+$, or with organic cations as counter ion but organic counter ions lead to less to less viscous suspensions than $Na^+$ in particular when the number of carbon atoms of the aliphatic chain increases from 1 to 3.

• Journal of the Optical Society of Korea
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• v.17 no.5
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• pp.362-370
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• 2013

In this paper, we propose a novel optical implementation of a 3DES algorithm based on dual XOR logic operations for a cryptographic system. In the schematic architecture, the optical 3DES system consists of dual XOR logic operations, where XOR logic operation is implemented by using a free-space interconnected optical logic gate method. The main point in the proposed 3DES method is to make a higher secure cryptosystem, which is acquired by encrypting an individual private key separately, and this encrypted private key is used to decrypt the plain text from the cipher text. Schematically, the proposed optical configuration of this cryptosystem can be used for the decryption process as well. The major advantage of this optical method is that vast 2-D data can be processed in parallel very quickly regardless of data size. The proposed scheme can be applied to watermark authentication and can also be applied to the OTP encryption if every different private key is created and used for encryption only once. When a security key has data of $512{\times}256$ pixels in size, our proposed method performs 2,048 DES blocks or 1,024 3DES blocks cipher in this paper. Besides, because the key length is equal to $512{\times}256$ bits, $2^{512{\times}256}$ attempts are required to find the correct key. Numerical simulations show the results to be carried out encryption and decryption successfully with the proposed 3DES algorithm.

• Journal of Life Science
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• v.22 no.3
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• pp.387-397
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• 2012

In this study, we focused on myomoduline A (MMA) released from the central nervous system of Aplysia kurodai. The primary structure of MMA is Pro-Met-Ser-Met-Leu-Arg-Leu-$NH_2$. This peptide is the same as that of the myomodulin family peptide found in other mollusks. The purified MMA showed a modulating activity of phasic contraction on the anterior byssus retractor muscle (ABRM) of Mytilus edulis. In order to study the relationship between the structure and biological activity of MMA, we synthesized MMA, Des[$Pro^1$]-MMA, Des[$Pro^1,Met^2$]-MMA, Des[$Pro^1,Met^2,Ser^3$]-MMA, and MME. The amino acid sequences of Des[$Pro^1$]-MMA, Des[$Pro^1,Met^2$]-MMA, and Des[$Pro^1,Met^2,Ser^3$]-MMA were Met-Ser-Met-Leu-Arg-Leu-$NH_2$, Ser-Met-Leu-Arg-Leu-$NH_2$, and Met-Leu-Arg-Leu-$NH_2$, respectively. MMA and synthetic peptides were tested on ABRM in M. edulis as well as muscle preparations in Achatina fulica. At $1{\times}10^{-8}$ M or lower, MMA showed a potentiating effect on phasic contraction of the ABRM, but this peptide had an inhibitory effect at $1{\times}10^{-6}$ M or higher. Both MMA and its analogs stimulated a contractile response on the crop and a relaxed catch-relaxing response on the penial retractor muscle of A. fulica. These results suggest that Met-Leu-Arg-Leu-$NH_2$ in MMA is the minimum structure required for the regulation of the contraction of ABRM, as well as the reproductive and digestive activities of mollusks.

• Animal cells and systems
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• v.14 no.3
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• pp.161-167
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• 2010

This study investigated the estrogenicity of 4-nonylphenol (NP) and diethylstilbestrol (DES) in vitro during oocyte maturation in the marine fish, Tridentiger obscurus, using steroid hormone assays and GVBD assay. Vitellogenic (0.53mm diameter) and fully vitellogenic (0.75mm diameter) oocytes were in vitro exposed to NP (0.045 453.82 nM and DES (0.037 372.62 nM). In vitellogenic oocytes, 45.38 and 453.82nM NP and 3.73 372.62nM DES increas the estradiol-$17{\beta}$ (E2)/testosterone (T) ratio. In fully vitellogenic oocytes, 0.45, 45.38 and 453.82nM NP and 3.73nM DES increased E2/T. In the GVBD assay, 0.45 and 4.54nM NP and 0.037, 3.73 and 37.26nM DES inhibited GVBD. These results suggest that NP and DES have estrogen-agonistic effects in oocyte maturation in T. obscurus. In addition, NP and DES have different sensitivity according to the oocyte developmental stage, and the estrogenagonistic effects of DES were greater than were those of NP.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.374-376
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• 2005

In this paper, we presented our implementation of 3DES and HMAC-MD5 processing functionality in Intel? IXP 2400 platform. It can be used as encryption and authentication engine for VPNs such as IPsec and SSL.

• Environmental Analysis Health and Toxicology
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• v.6 no.1_2
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• pp.39-57
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• 1991

The effect of red ginseng ethanol extract on the immunotoxicity of diethylstilbestrol (DES) was studied in ICR mice. ICR male mice were divided into S groups (10 mice/group), and red ginseng ethanol extract (50, 100 and 200 mg/kg body wt., respectively) and DES (1 mg/kg body wt.) were injected intraperitoneally (i.p.) to ICR mice once a day for 2 weeks. Mice were sensitized and challenged with sheep red blood cells (S-RBC). Immune response were evaluated by humoral immunity, cell-mediated immunity, non-specific immunity, and circulating leukocyte counts. The results of this study were summarized as followings: 1. The DES-treated control group as compared with normal group showed the tendency to decrease body weight rate and relative liver weight, decreased both humoral and cellular immune responses, phagocyte activity, and circulating leukocyte counts, but increased the natural killer (NK) cell activity. 2. Compared with the DES-treated control group, DES plus red ginseng ethanol extract-treated groups significantly decreased the body weight rate (P<0.01). Relative liver weight was significantly decreased in DES plus red ginseng ethanol extract (50mg/kg)-treated group (P<0.01), but significantly increased in DES plus red ginseng ethanol extract (100mg/kg)-treated group (P<0.01). Relative spleen and thymus weights were significantly enhanced in DES plus red ginseng ethanol extract (100 mg/kg)-treated group (P<0.01), but significantly decreased in DES plus red ginseng ethanol extract (200 mg/kg)-treated group (P<0.01). 3. Both humoral and cellular immune responses were significantly decreased in DES plus red ginseng ethanol extract-treated groups rather than in the DES-treated control group (P<0.01). Especially, it weakened the decrease in DES plus red ginseng ethanol extract (100 mg/kg)-treated group. 4. Phagocyte activity and circulating leukocyte counts were significantly decreased in DES plus red ginseng ethanol extract-treated groups rather than in the DES-treated control group (P<0.01). Especially, it weakened the decrease in DES plus red ginseng ethanol extract (100 mg/kg)-treated group. NK cell activity was significantly enhanced in DES plus red ginseng ethanol extract (100 mg/kg)-treated group (P<0.01), but significantly decreased in DES plus red ginseng ethanol extract (50 and 200 mg/kg)-treated groups (P<0.01).

• Journal of Electrochemical Science and Technology
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• v.8 no.3
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• pp.206-214
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• 2017

SnS films have been prepared by electrodeposition technique onto Cu and ITO substrates using acidic solutions containing tin chloride and sodium thiosulfate with sodium citrate as an additive. The effects of sodium citrate on the electrochemical behavior of electrolyte bath containing tin chloride and sodium thiosulfate were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were characterized by XRD, FTIR, SEM, optical, photoelectrochemical, and electrical measurements. XRD data showed that deposited SnS with sodium citrate on both substrates were polycrystalline with orthorhombic structures and preferential orientations along (111) directions. However, SnS films with sodium citrate on Cu substrate exhibited a good crystalline structure if compared with that deposited on ITO substrates. FTIR results confirmed the presence of SnS films at peaks 1384 and $560cm^{-1}$. SEM images revealed that SnS with sodium citrate on Cu substrate are well covered with a smooth and uniform surface morphology than deposited on ITO substrate. The direct band gap of the films is about 1.3 eV. p-type semiconductor conduction of SnS was confirmed by photoelectrochemical and Hall Effect measurements. Electrical properties of SnS films showed a low electrical resistivity of $30{\Omega}cm$, carrier concentration of $2.6{\times}10^{15}cm^{-3}$ and mobility of $80cm^2V^{-1}s^{-1}$.

• Proceedings of the Korean Magnestics Society Conference
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• 2008.12a
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• pp.116.2-116.2
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• 2008

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.56-60
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• 2006

We review our studies on the growth of microcrystalline silicon films by the standard PECVD technique. In situ spectroscopic ellipsometry studies allow the optimization of the complex film structure with respect to competing aspects of the growth process. Fine tuning the hydrogen flux, the ion energy, and the nature of the species contributing to deposition produces unique films with a fully crystallized interface with silicon nitride. These materials have been successfully incorporated in bottom gate TFTs which present mobility values in the range of 1 to 3 $cm^2/V.s$, and stable characteristics when submitted to a bias stress. The stability of these TFTs makes them suitable for driver applications in AMLCDs as well as pixel elements in OLED displays.

• Journal of the Korean Geographical Society
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• v.25
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• pp.40-69
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• 1982

이 글에서는 다음의 내용을 다루었다. 1. Difficultes statistiques 2. Difficultes conceptuelles 3. Resultats globaux. 4. Les espaces industriels en 1915 : I'apparition des foyers industriels en Coree et des regions desequilibrees en France. 5. Les espaces industriels en 1930 : des foyers industriels disperses en Coree et trois massives regions industrielles en France. 6. Les espaces industriels en 1940 : I'apparition de desequilibres regionaux en Coree et le renforcement des desequilibres en France. 7. Cycle economique et espace industriel.