• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.555-560
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• 2006

As it has been reported that more than 60% of transmission line faults occurs due to lightning strokes, lighting is one of concerned issues in electric power utility company. Most of transmission line is double circuit in Korea. Double circuit outages account for 33.7 percent of total lightning faults from 1996 to 2004. Even though transmission fault might be cleared shortly by protective system, it could deteriorate the power quality accompanied with sag or flicker. Moreover, double circuit fault may lead to more aggravated situation, for instance, blackout. To Protect transmission lines from lightning stroke, reduction of tower footing resistance, multiple ground wires and unbalanced insulation in double circuit lines have been adopted. In this paper, we would like to introduce insulation design standards for lightning protection of Korea Electric Power Corporation.

• Journal of Ship and Ocean Technology
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• v.3 no.1
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• pp.12-26
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• 1999

A new concept of collision energy absorbing system for ;he New Oil-tankers with Advanced Double Hull Structure(NOAHS and NOAHS II) are presented through the joint-research pro-gran between Inha and Hamburg-Harburg University. A comparative study on col vision resistance of these proposed side structures with standard double hull structure of 310K DWT class VLCC, is carried out. The fatigue investigation of structural detail parts is also included. It contains a comparative fatigue study based on pertinent regulations of Classification Societies.

• ETRI Journal
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• v.44 no.1
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• pp.147-154
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• 2022

We demonstrate a new double-layer structure for stretchable interconnects, where the top surface of a serpentine polyimide support is coated with a thin eutectic gallium-indium liquid metal layer. Because the liquid metal layer is constantly fixed on the solid serpentine body in this liquid-on-solid structure, the overall stretching is accomplished by widening the solid frame itself, with little variation in the total length and cross-sectional area of the current path. Therefore, we can achieve both invariant resistance and infinite fatigue life by combining the stretchable configuration of the underlying body with the freely deformable nature of the top liquid conductor. Further, we fabricated various types of double-layer interconnects as narrow as 10 ㎛ using the roll-painting and lift-off patterning technique based on conventional photolithography and quantitatively validated their beneficial properties. The new interconnecting structure is expected to be widely used in applications requiring high-performance and high-density stretchable circuits owing to its superior reliability and capability to be monolithically integrated with thin-film devices.

• 한국전기화학회:학술대회논문집
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• 2002.10a
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• pp.54-54
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• 2002

• Corrosion Science and Technology
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• v.20 no.6
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• pp.492-492
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• 2021

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.38-38
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• 2015

Throughout the world, clubroot disease is one of the most damaging diseases affecting Brassica oleracea. In order to perform QTL analysis of CR (clubroot resistance) loci in B. oleracea, we constructed a map, and analyzed CR-QTLs using the mean phenotypes of F3 progenies from the cross of a resistant double-haploid cabbage line (Anju) with a susceptible double-haploid broccoli line (GC). We identified one major QTL, pb-Bo(Anju)1 in C2 from Anju and four minor QTLs; pb-Bo(GC)1 in O5 from GC, pb-Bo(Anju)2, -3, -4 in C2, C3, and C7 from Anju, respectively. Additionally, we found that the accumulation of Pb-Bo(Anju)1 allele and the minor CR-QTLs is essential for resistance against various six isolates. Our finding markers closely linked to the CR-QTLs will help marker-assisted selection for CR. At present, we are undergoing toward map-based cloning for Pb-Bo(Anju)1 gene. The preliminary experiment delimited Pb-Bo(Anju)1 locus, encompassing among 450kB.

• Restorative Dentistry and Endodontics
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• v.44 no.4
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• pp.36.1-36.6
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• 2019

Objectives: The aim of this study was to compare the cyclic fatigue resistance of the WaveOne Gold Glider, ProGlider and One G glide path instruments in artificial doublecurvature canals. Materials and Methods: This study included 15 WaveOne Gold Glider (size 15/0.08), 15 ProGlider (size 16/0.08), and 15 One G (size 16/0.06) nickel titanium files. The files were used in accordance with the manufacturer's instructions until they were broken in artificial double-curvature canals made of stainless steel. The time to fracture was recorded via a digital stopwatch and the number of rotations until fracture was also calculated. The data were statistically analyzed via the Kruskal-Wallis test. Results: The highest average number of rotations until fracture of the files was found for the WaveOne Gold Glider, followed by ProGlider and One G in order. Statistically significant differences were present between all groups of files (p < 0.05). Conclusions: In our study, the resistance of the WaveOne Gold Glider nickel-titanium (Ni-Ti) file to cyclic fatigue in S-shaped curved canals was found to be higher than that of the ProGlider and One G Ni-Ti files.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.4
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• pp.45-56
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• 2011

This paper is proposed artificial neural network(ANN) rotor resistance estimation of induction motor drive controlled by multi-adaptive fuzzy learning controller(AFLC). A simple double layer feedforward ANN trained by the back-propagation technique is employed in the rotor resistance identification. In this estimator, double models of the state variable estimations are used; one provides the actual induction motor output states and the other gives the ANN model output states. The total error between the desired and actual state variables is then back propagated to adjust the weights of the ANN model, so that the output of this model tracks the actual output. When the training is completed, the weights of the ANN correspond to the parameters in the actual motor. The estimation and control performance of ANN and multi-AFLC is evaluated by analysis for various operating conditions. Also, this paper is proposed the analysis results to verify the effectiveness of this controller.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.10
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• pp.23-28
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• 2010

Resistance trimming and cutting processes of printed circuit board by making use of high power UV laser with nano-second pulse width have been proposed and investigated experimentally. Also laser-based application system with high flexibility and complex has been designed and adopted power controller, auto beam size control, auto-focusing and control program developed for ourselves. The function of each module shows that they can be reliable for industrial equipments. Resistance trimming method used a plunge and double cut process with $20{\mu}m$ spot size beam. Results show that double cut process is more effective to control resistance trimming in precision than plunge cut process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.247-248
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• 2018

In order to secure the variability of long-life housing, dry walls are used. The composite gypsum board panel is the most frequently used infill system for the wall, and it is an excellent construction method in terms of constructability and economic feasibility. However, there are also problems such as the destruction of Ondol pipes at the bottom floor and being unable to fix the light weight steel frame (M-bar) when a variable composite gypsum board panel is used. To solve such problems, a wall with a method of fixing only the top part without fixing the bottom floor is developed, but it is difficult to identify the durability of ceiling frame according to the tensile force of stud and the safety according to the Stiffness and impact resistance (soft body) of ceiling frame. Therefore, this study verified the effectiveness of infill system for the wall by conducting experiment on the stiffness and impact resistance of composite gypsum board panel according to the reinforcement of ceiling frame (wooden frame, double saw-toothed bracket, Cross M-bar). As a result, it was possible to secure the safety of wooden frame while the impact resistance and the Stiffness of double saw-toothed bracket and cross M-bar were not secured.