• Textile Coloration and Finishing
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• v.19 no.4
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• pp.26-31
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• 2007

Nanocomposite resin(PUD-CNT) composed of Carbon nanotube(CNT) and Polyurethane Dispersion (PUD) was prepared by different contents of CNT($0{\sim}5%$). PUD-CNT was coated on samples, and their electrical conductivity was investigated. With increasing CNT content, static change, half life and surface resistance decreased. Composites having 5% CNT showed $10^9{\Omega}/cm$(surface resistance), and 40V (stactic charge). Respectively, From this results, PUD-CNT can be used as a antistatic material.

• Journal of the Korean Professional Engineers Association
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• v.16 no.2
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• pp.1-11
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• 1983

The resistance property of a high speed passenger craft (: "DOL-PIN HO" designed by the author in 1972) is investigated as follows; -. The Resistance property of the craft is determined by savitsky′s method and blount-Fox′s method. The theoretical results are also compared with the full scale data. The comparison reveals that the result when using blount/fox′s method are in much closer agreement with the full scale data than savitsky′s. -. The effects of ship speed on the positions of the center of pressure and of the longitudinal center of gravity (L.C.G.) are investigated. The investigation shows that the position of L.C.G. of the craft is almost constant although the ship speed is changed. -. The effect of transom flap on the Resistance property of the craft is studied using savitsky/brown′s method. From the study it is found that the resistance of the craft is decreased and hence speed gain (about 3% of the service speed) can be obtained, when using transom flap for the craft.

• Geomechanics and Engineering
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• v.23 no.5
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• pp.481-491
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• 2020

Piles installed in row(s) are used as an effective technique to improve the stability of soil slopes. The analysis of pile-stabilized slopes require a reliable prediction of lateral resistance offered by the piles. In this work, an analytical solution is developed to estimate the lateral resistance offered by the stabilizing piles in sand and c - 𝜙 soil slopes considering soil arching phenomenon. The soil arching in both horizontal direction (between the neighboring piles) and vertical direction (in the active wedge in front of the pile row) are studied and their effects are incorporated in the proposed model. The shape of soil arch is assumed to be circular and principal stress trajectories are defined separately for both modes of arching. Experimental and numerical studies found in literature were used to validate the proposed method. A detailed parametric analysis was performed to study the influence of pile diameter, center-to-center spacing, slope angle and angle of internal friction on the lateral pile resistance.

• Journal of Yeungnam Medical Science
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• v.38 no.2
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• pp.83-94
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• 2021

The global obesity epidemic and the growing elderly population largely contribute to the increasing incidence of type 2 diabetes. Insulin resistance acts as a critical link between the present obesity pandemic and type 2 diabetes. Naturally occurring reactive oxygen species (ROS) regulate intracellular signaling and are kept in balance by the antioxidant system. However, the imbalance between ROS production and antioxidant capacity causes ROS accumulation and induces oxidative stress. Oxidative stress interrupts insulin-mediated intracellular signaling pathways, as supported by studies involving genetic modification of antioxidant enzymes in experimental rodents. In addition, a close association between oxidative stress and insulin resistance has been reported in numerous human studies. However, the controversial results with the use of antioxidants in type 2 diabetes raise the question of whether oxidative stress plays a critical role in insulin resistance. In this review article, we discuss the relevance of oxidative stress to insulin resistance based on genetically modified animal models and human trials.

• Molecules and Cells
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• v.20 no.3
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• pp.385-391
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• 2005

As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.558-561
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• 2001

Vanadium oxide ($VO_x$) thin films are very good candidate material for uncooled infrared (IR) detectors due to their high temperature coefficient of resistance (TCR) at room temperature. But, the deposition of $VO_x$ thin films showing good electrical properties is very difficult in micro bolometer fabrication process using sacrificial layer removal because of its low process temperature and thickness of thin films less than $1000{\AA}$. This paper presents a new fabrication process of $VO_x$ thin films having high TCR and low resistance. Through sandwich structure of $VO_{x}(100{\AA})/V(80{\AA})/VO_{x}(500{\AA})$ by sputter method and post-annealing at oxygen ambient, we have achieved high TCR more than $-2%/^{\circ}C$ and low resistance less than $10K\Omega$ at room temperature.

• Corrosion Science and Technology
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• v.3 no.4
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• pp.154-160
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• 2004

The Sulfide Stress Corrosion Cracking (SSCC) resistance of structural steels is one of the critical concerns for the operators, material designers, and fabricators of oil-field equipment, especially treating sour gas (H2S) containing fluids. As far as its fabricators concerned, the systematic care of welding parameters should be taken to obtain comparable SSCC resistance of their weldment to that of its base material. In this respect, every different type of welding joint design for this use should be verified to be SSCC-proof with relevant test procedures. In this study, the welding parameters to secure a proper SSCC resistance of steel pipe's weldments were reviewed on the Welding Procedure Qualification Records (WPQR), which had been employed for actual fabrication of an offshore structure for oil and gas production. Based on this review, a guideline of welding parameters, such as, heat input, welding consumable for Y.S. 65 ksi class steel pipe material is proposed in terms of the NACE criteria for SSCC resistance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.558-561
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• 2001

Vanadium oxide ($VO_{x}$) thin films are very good candidate material for uncooked infrared (IR) detectors due to their high temperature coefficient of resistance (TCR) at room temperature. But, the deposition of $VO_{x}$ thin films showing good electrical properties is very difficult in micro bolometer fabrication process using sacrificial layer removal because of its low process temperature and thickness of thin films less than 1000${\AA}$. This paper presents a new fabrication process of $VO_{x}$ thin films having high TCR and low resistance. Through sandwich structure of $VO_{x}$(100${\AA}$)/V(80${\AA}$)/$VO_{x}$(500${\AA}$) by sputter method and post-annealing at oxygen ambient, we have achieved high TCR more than -2%/$^{\circ}C$ and low resistance less than $10K\Omega$ at room temperature.

• Corrosion Science and Technology
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• v.7 no.6
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• pp.301-306
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• 2008

Surface composite layers of 1.9~2.9 mm in thickness were fabricated by depositing metamorphic powders on a carbon steel substrate and by irradiating with a high-energy electron beam. In the surface composite layers, 48~64 vol.% of $Cr_{2}B$ or $Cr_{1.65}Fe_{0.35}B_{0.96}$ borides were densely precipitated in the austenite or martensite matrix. These hard borides improved the hardness of the surface composite layer. According to the otentiodynamic polarization test results of the surface composites, coatings, STS304 stainless steel, and carbon steel substrate, the corrosion potential of the surface composite fabricated with 'C+' powders was highest, and its corrosion current density was lowest, while its pitting potential was similar to that of the STS304 steel. This indicated that the overall corrosion resistance of the surface composite fabricated with 'C+' powders was the best among the tested materials. Austenite and martensite phases of the surface composites and coatings was selectively corroded, while borides were retained inside pits. In the coating fabricated with 'C+' powders, the localized corrosion additionally occurred along splat boundaries, and thus the corrosion resistance of the coating was worse than that of the surface composite.

• Journal of the Korean Ceramic Society
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• v.42 no.12 s.283
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• pp.833-841
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• 2005

The oxidation resistance and electrical conductivity of various commercial ferritic stainless steels including STS444 were tested in an air atmosphere at $700^{\circ}C$. Crofer22 developed specially for SOFC interconnect was also examined for the aim of comparing with the test results of STS444. Although STS444 exhibited higher oxidation resistance than Corfer22, the electrical conductivity of the scale formed on Crofer22 was higher, indicating that the resistivity of scale formed on Crofer22 is much lower than that of STS444. To gain a better understanding of the relation between oxidation behavior and electrical conductivity, the oxide scales formed on STS444 and Crofer22 were analyzed in terms of the structure, composition, and phase. Consequently, the influence of alloying elements on electrical conductivity of Fe-Cr alloys was discussed.