• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.187-190
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• 2003

An Fe-25Cr steel was oxidized in Ar at 973K with or without external stesses of 30~35Mpa. A 0.1 ${\mu}{\textrm}{m}$ thick Cr$_2$O$_3$scales was formed during pre-treatment in Ar. Cracking on the oxides scales commenced at the alloy grain boundary by the end of second creep stage, arrayed almost perpendicular to the direction of the tensile directions. On the contrary, a scale formed in $N_2$-0.1%SO$_2$shows poor adherence on the metal substrate. In this case, the strength of materials is much lower than in Ar

• Journal of the Korean Ceramic Society
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• v.15 no.2
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• pp.89-97
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• 1978

The basic mechanism of adherence in sintered high purity alumina ceramic-to-metal bonding was studied. Emphasis was placed on flux composition, porosity of the fired ceramics, and metallizing mixtures. The study was conducted on 95 and 99.5% alumina, using molydbenum-manganese, molybdenum-manganese-silicon dioxide metallizing compositions. Metallizing was performed in wet hydrogen (dew point, ＋17$^{\circ}C$) at 145$0^{\circ}C$ for 45min. This experiment indicated that adhernece mechanism of ultra high purity alumina ceramic was attributed to formation of $MnAl_2O_$4, and in the case of 95% alumina containing glass, the migration of glass from the interface into the void of the metal coating was the main role to the adhrence. It showed also that greater the bond-strength was resulted as porosity was increased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.195-196
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• 2012

Because of the high level of the safety and durability, a lot of reinforcing bars is placed in the concrete structure of the Nuclear Power Plant. But the overcrowding re-bars cause some problems during the construction as the diseconomy, construction delay, quality deterioration, and so on. These problems can be solved by applying the high-strength reinforcing bars to NPP structure. To achieve this, after analysing the structural target performance like the control of cracks, adherence, shear, torsion, development of reinforcement and earthquake-resistance, the results of the analysis will be reflected in the structural performance evaluation test.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.163-172
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• 2010

In order to investigate the changes in mechanical properties of sanitary nonwoven fabrics actually used as a top sheet, the fabric was treated with a mixture of chitosan and nanosilver colloidal solution in accordance with the prescribed ratio. The former is a natural polymer with excellent biocompatibility and the latter can give an additional performance while compensating the weaknesses of chitosan of deteriorating adherence efficiency. It was shown that the bending and shearing characteristics of the chitosan/nanosilver treated fabrics decreased, which helped to make it softer, smoother and more flexible. The shape stability and drapability of the treated fabrics improved. As KES-FB system evaluation showed that Koshi was deduced, and both Numeri and Fukurami were increased. Thereby, the chitosan/nanosilver treated fabrics were smoother to provide elasticity. In the change of hand value compared to chitosan only treatment, a better THV was shown in the fabrics treated with chitosan/nanosilver mixed solution than the fabric treated with chitosan alone.

• International Journal of Quality Innovation
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• v.5 no.2
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• pp.26-44
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• 2004

Distance Education is a non-traditional mode of training and can take many forms, one of which is the use of Computer Based Training (CBT). This paper reviews various quality assurance models for designing the delivery of programmes at the universities and other training institutions. It presents the findings of a CBT research that is currently being carried out at the Department of Mechanical and Manufacturing Engineering, University of the West Indies, Trinidad. The significance of the research is discussed with particular emphasis on the influence of curricula sequencing on knowledge acquisition in learners of varying cognitive styles. The paper concludes that adherence to quality assurance principles could result in the enhanced performance of users of the CBT.

• The Journal of the Korean dental association
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• v.38 no.3 s.370
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• pp.288-292
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• 2000

Perhaps the most frustrating scenario in dentistry lies in the apparently well-instrumented and well-obturated tooth that, becomes symptomatic after treatment of shows a periapical lesion on recall examination. Conventional root canal treatment demands stringent adherence to asepsis, awareness of canal morphology, and mastery of a variety of clinical techniques. But the risk of endodontic failure does not end with canal obturation. The quality of the coronal restoration may have a greater bearing on the ultimate success of a case than the quality of the root canal treatment itself. This review of the endodontic literature will define coronal leakage, describe its influence on endodontic treatment failures, and make specific recommendations on prevention.

• Korean System Dynamics Review
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• v.16 no.4
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• pp.5-30
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• 2015

This study analyses the inter-relationships between Safety Cultural Elements by System Dynamics approach. Base Frame for Safety Culture, which is originated from IAEA, NRC and INPO's Safety Culture Documents, helps to elaborate the Causal Loop Diagram of Safety Culture in Nuclear Power Plant(NPP). Also, the simulation results show that ownership of employees is degraded continually and adherence of technical standards is violated because workloads of the employees cannot be minimized and stress and time pressure maintains a high level in NPP.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.796-801
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• 2007

This study was conducted to investigate antioxidant activity and anti-immunological inflammatory effect of Allium victorialis subsp. platyphyllum extracts (AVPEs). Antioxidant activities of AVPEs were determined by free radical scavenging assay and reducing power test. Leaf-part extract had comparatively better antioxidant activity than other-part extracts. Antioxidant activity of extracts had protective effect for human umbilical vein endothelial cells (HUVECs) against superoxide anions secreted from activated neutrophils. Also, we observed AVPEs had inhibitory effects on the adherence of monocytic THP-1 to HUVEC monolayer to the basal level. Inhibitory effect on cell adhesion was caused by suppression of tumor necrosis factor-${\alpha}\;(TNF-{\alpha})-upregulated$ expression of vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin in HUVECs. From these results, we expect to support the evidence of anti-immunological inflammatory effects of Allium victorialis subsp. platyphyllum (AVP) as a Korean traditional pharmaceutical.

• Computers and Concrete
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• v.16 no.1
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• pp.1-16
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• 2015

The proposed techniques to strengthen concrete members such as steel plates, polymers or concrete have important deficiencies in adherence and durability. The use of UHPFC plates can overtake effectively these problems. In this paper, the possibility of using UHPFC to strengthen RC beams under torsion is investigated. Four specimens of concrete beams reinforced with longitudinal bars only were tested under pure torsion. One of the beams was considered as the baseline specimen, while the others were strengthened by ultra-high-performance fiber concrete (UHPFC) on two, three, and four sides. Finite element analysis was conducted in tandem with experimental work. Results showed that UHPFC enhances the strength, ductility, and toughness of concrete beams under torsional load, and that finite element analysis is in good agreement with the experimental data.

• Journal of the Korean Applied Science and Technology
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• v.34 no.3
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• pp.650-656
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• 2017

The water-swollen hydrogels containing silicone or fluorine were prepared by copolymerization of 2-hydroxy ethyl methacylate (HEMA) with 3-(trimethoxysilyl)propyl methacrylate(SM) or 2,2,2-trifluoroethyl acrylate(FA). When the content of SM or FA increased in copolymers, there was tendency of water absorbance to decrease, whereas contact angles to increase. The hydrogels containing FA showed 2 ~ 4% higher water content and 4 ~ 5% lower contact angles compared to that of SM. Tensile strengths decreased as the content of SM increased. However, FA exhibited strength of $2.2Mpa/cm^2$ which is similar to $2.3Mpa/cm^2$ of B. FA, which implies comparatively low adherence, hence, showed better protein resistance properties than SM-based hydrogel. The photo-polymerization was also applied instead of thermal polymerization to enhance the energy efficiency. As a result, the reaction yield reached over 95% within 1 minute.