• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.1
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• pp.67-73
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• 2009

The stress-strain behavior and its effects on the crack initiation and growth of ITO film on PET substrate with a sheet resistance of 45 ohms/sq were investigated. Electrical resistance increased gradually at the strain of 0.7% in the elastic to plastic transition region of the stress strain curves. Numerous cracks were observed after 1% strain and the increase of the resistance can be linked to the cracking of ITO thin films. The onset strain for the increase of resistance increased with increasing strain rate, suggesting the crack initiation is dependent on the strain rate. Upon loading, the initial cracks perpendicular to the tensile axis were observed and propagated the whole sample width with increasing strain. The spacing between horizontal cracks is thought to be determined by the fracture strength and the interfacial strength between ITO and PET. The crack density increased with increasing strain. The spacing between horizontal cracks (perpendicular to the stress axis) increased with decreasing strain rate, The increase of crack density with decreasing strain rate can be attributed to the higher fraction of the plastic strain to the total strain at a given total strain. As the strain increased over 5% strain, cracks parallel to the stress axis were developed and increased in number with strain, accompanied by drastic increases of resistance.

• Restorative Dentistry and Endodontics
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• v.48 no.4
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• pp.34.1-34.12
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• 2023

This systematic review aimed to investigate whether minimally invasive root canal preparation ensures higher fracture resistance compared to conventional root canal preparation in endodontically treated teeth (ETT). A comprehensive search strategy was conducted on the "PubMed, Web of Science, and Scopus" databases, alongside reference and hand searches, with language restrictions applied. Two independent reviews selected pertinent laboratory studies that explored the effect of minimally invasive root canal preparation on fracture resistance, in comparison to larger preparation counterparts. The quality of the studies was assessed, and the risk of bias was categorized as low, moderate, or high. The electronic search yielded a total of 1,767 articles. After applying eligibility criteria, 8 studies were included. Given the low methodological quality of these studies and the large variability of fracture resistance values, the impact of reduced apical size and/or taper on the fracture resistance of the ETT can be considered uncertain. This systematic review could not reveal sufficient evidence regarding the effect of minimally invasive preparation on increasing fracture resistance of ETT, primarily due to the inherent limitations of the studies and the moderate risk of bias.

• Korean Journal of Veterinary Service
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• v.31 no.1
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• pp.17-29
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• 2008

In this study, antimicrobial resistance of E coli isolated from domestic beef on sale in Busan and Gyeongnam province was investigated from March to October 2007. A total of 600 beef samples were collected for the monitoring of antimicrobial resistance, and 92 (15.3%) strains of E coli were isolated. Antimicrobial resistance test was carried out by agar disc diffusion method with 17 antimicrobials. In general, E coli isolates showed the highest antimicrobial resistance to doxycycline (73.9%), followed by tetracycline (70.7%) andcefazolin (63.0%). Then they showed higher resistance to several antimicrobials like norfloxacin (48.9%). However, They had low antimicrobial resistance to amikacin (4.3%), colistin (1.1%). Of 92 isolates, 82 (89.1%) were resistant to more than 2 antimicrobials. Among 17 antimicrobials examined, tetracyclines were the most resistant, followed by cephalosporins, quinolone. The resistance was seemed to be correlated to amounts of antimicrobial use. In the result of this study, we suggest that there be need to regulate the abuse of antimicrobial on food-producing animals in Korea because the concern on antimicrobial resistant is gradually increased worldwide.

• Journal of Ocean Engineering and Technology
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• v.36 no.2
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• pp.83-90
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• 2022

This paper presents the minimum submergence depth of an underwater vehicle that can remove the effect of free surface on the resistance of the underwater vehicle. The total resistance of the underwater vehicle in fully submerged modes comprises only viscous pressure and friction resistances, and no wave resistance should be present, based on the free surface effect. In a model test performed in this study, the resistance is measured in the range of 2 to 10 kn (1.03-5.14 m/s) under depth conditions of 850 mm (2.6D) and 1250 mm (3.8D), respectively, and the residual resistance coefficients are compared. Subsequently, resistance analysis is performed via computational fluid dynamics (CFD) simulation to investigate the free surface effect based on various submergence depths. First, the numerical analysis results in the absence of free surface conditions and the model test results are compared to show the tendency of the resistance coefficients and the reliability of the CFD simulation results. Subsequently, numerical analysis results of submergence depth presented in a reference paper are compared with the model test results. These two sets of results confirm that the resistance increased due to the free surface effect as the high speed and depth approach the free surface. Therefore, to identify a fully submerged depth that is not affected by the free surface effect, case studies for various depths are conducted via numerical analysis, and a correlation for the fully submerged depth based on the Froude number of an underwater vehicle is derived.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.802-805
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• 2004

This study was performed to investigate the effect of mineral admixture' type and replacement ratios on the chloride penetration resistance of concrete which was immersed in the artificial chloride solution. The chloride penetration resistance was evaluated by penetration depth and chloride diffusion coefficient. As a result, all of the mineral admixtures were effective on the chloride penetration resistance of concrete compared to ordinary portland cement only.

• 전기의세계
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• v.22 no.6
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• pp.33-51
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• 1973

To lower the earth resistance shall be one of the most effective method for the prevention of lightening damage on power transmission line. In this report, in order to investigate various characteristic necessary to lowering the earth resistance, the following experiments have been made at 154KV U1San-PoHang T/L, 154KV YoSu-SoonChun T/L and so on. 1. Measurement of Earth specific resistance, 2. Efficiency of Earthing of concrete foundation for steel structure., 3. Efficiency of Earthing with counter poise., 4. Compound impulse test with foundation of steel structure and counter poise. With the above investigate a guidance have been prepared for the effective work-performance of steel structure.

• Corrosion Science and Technology
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• v.12 no.5
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• pp.203-208
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• 2013

The electrocoating for automotive bodies is pigmented with a mixture of titanium dioxide and kaolin. In this study, the effects of titanium dioxide and kaolin contents in coating on electrodeposition process, drying, and surface properties such as surface roughness, gloss, impact resistance and corrosion resistance were investigated. Titanium dioxide and kaolin in coating do not have a decisive effect on curing reaction during drying and corrosion resistance but on gloss, surface roughness, impact resistance and electrodeposition process of coating. According to its size and shape on coating surface, pigment contents increased during drying process. However, the contents of kaolin and $TiO_2$ in coating didn't affect the corrosion resistance on zinc phosphated substrate, and the curing properties.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.4
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• pp.246-248
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• 2000

Closed-form expressions for the temperature dependent breakdown voltage and the on-resistance of the Si power MOSFETs were derived by employing effective temperature dependent ionization coefficient for electrons and holes. The breakdown voltage increases by 20% and the on-resistance increases 2 times when the temperature increases from 300 K to 423 K. The analytic results normalized to the values at 300 K show good agreement with the experimental data of Motorola within 3.5% and 7% for the breakdown voltage and the on-resistance, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.10
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• pp.713-719
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• 2013

Power MOSFET operate voltage-driven devices, design to control the large power switching device for power supply, converter, motor control, etc. We have optimal designed planar and trench gate power MOSFET for high breakdown voltage and low on resistance. When we have designed $6,580{\mu}m{\times}5,680{\mu}m$ of chip size and 20 A current, on resistance of trench gate power MOSFET was low than planar gate power MOSFET. The on state voltage of trench gate power MOSFET was improved from 4.35 V to 3.7 V. At the same time, we have designed unified field limit ring for trench gate power MOFET. It is Junction Termination Edge type. As a result, we have obtained chip shrink effect and low on resistance because conventional field limit ring was convert to unify.

• The Journal of Information Systems
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• v.28 no.3
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• pp.123-139
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• 2019

Purpose With the development of information and communication technologies. fintech industry is rapidly growing as a major financial service. Previous research literatures mainly focused on overall characteristics and technical aspects of fintech including security issues. Therefore, this study investigated the effect of individual features influencing the resistance of adopting a fintech service. Moreover, this paper included the guidelines in practical development of fintech mechanism. Design/methodology/approach For research purposes, this study developed research hypotheses in order to empirically examine the effect of the factors that might have a significant effect on the resistance of the wearable device. The empirical research was based on a survey which carried through 359 participants. Research hypotheses were evaluated via SPSS Statistics 21.0 and AMOS 19 statistical package program. Findings Results showed that self-efficacy and individual innovation had a significant effect on the technostress and switching cost. In addition, technostress, security and switching cost had a significant effect on the resistance of adopting a fintech service. However, more factors are needed to including in research model to generalize these results.