• Journal of the Semiconductor & Display Technology
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• v.13 no.3
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• pp.51-55
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• 2014

Ni-CNT(Carbon Nanotubes) composite coating is often used for the surface treatment of mechanical/electronic devices to improve the properties of the Ni coating. For the Ni-CNT coating, the dispersion of CNT fibers is a critical process. In this study, ultrasonic treatment instead of the conventional ball milling was attempted as a dispersion method for the electroless Ni-CNT coating. SEM-EDX analysis was performed and contact angle, sheet resistance, and micro-hardness were measured. Results showed that the ultrasonic treatment was comparable to the ball milling, as a dispersion method, but the difference was negligible. However, combined ball milling and ultrasonic treatment(double treatment) showed much improved micro-hardness value, above 350Hv(close to the value obtained by the Ni-CNT electroplating). In addition, electroless Ni-CNT(double-treated) coatings formed on the thin Ni film deposited by the electroless plating(double coating) showed better mechanical properties. Thus, double treatment and double coating are suggested as an improved electroless Ni-CNT coating method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.261-263
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• 2002

CMOS devices have scaled down to sub-50nm gate to achieve high performance and high integration density. Key challenges with the device scaling are non-scalable threshold voltage( $V^{th}$ ), high electric field, parasitic source/drain resistance, and $V^{th}$ variation by random dopant distribution. To solve scale-down problem of conventional structure, a new structure was proposed. In this paper, we have investigated double-gate MOSFET structure, which has the main-gate and the side-gates, to solve these problem.

• YAKHAK HOEJI
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• v.41 no.4
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• pp.533-537
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• 1997

The characteristics of the resistance phenotypes of Bacillus subtilis having ermk and its terminator region mutants were determined. Wild type ermK(pEC101) and pECMT109(methylase SD-region mutant) showed typical inducible resistance phenotype. pECMF1(terminator1 region mutant) and pECMT2(terminator2 region mutant) showed constitutive resistance to Kitasamycin but inducible resistance to tylosin. In contrast, pECMT3(terminator1 and terminator2 double mutant) and pECMT309(terminator1, terminator2 and methylase SD region triple mutant) showed constitutive resistance both to kitasamycin and tylosin.

• Korean Journal of Breeding Science
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• v.43 no.5
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• pp.413-421
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• 2011

The main objective of this study was to develop the multi-resistance lines to insects(brown planthopper; BPH, rice green leafhopper; GRH) and disease(blast; BL, bacterial blight; BB and rice stripe virus disease;RSV) with good grain quality and plant type by combining conventional breeding and marker assisted selection(MAS) and to eliminate the linkage drag effects between Bph1 gene and culm length, we conducted MAS of Bph1 gene in advanced backcross and double cross progenies. 'Nampyeong', 'Junam' and 'Milyang220' were used as the parent in this study. 'Milyang220' was used as the donor of brown planthopper resistance gene Bph1 with tall culm length. Two backcross progenies were developed using two recipients 'Nampyeong' carrying GRH resistance gene Grh3(t) with good grain appearance and 'Junam' harboring bacterial blight resistance gene Xa3 with short culm length. Two $BC_1$ generations were resulted from the backcrossing of the $F_1$ plants with recurrent parents 'Nampyeong' and 'Junam'. The second rounds of backcrossing($BC_2$) were derived from the cross of selected resistant $BC_1F_1$ plants based on heterozygous genotype of RM28493 linked to Bph1 gene. The double crossed population was constructed from the cross of between each heterozygous $BC_2F_1$ plants at RM28493 locus of '$Nampyeong^*3$ / Milyang220' and '$Junam^*3$ / Milyang220'., The homozygous alleles in Bph1 gene were selected using co-dominant DNA marker RM28493 in double crossed population. Eighty-five lines with multi-resistance to BL, BB, RSV, GRH and BPH were selected by bio-assay and MAS in generation of double crossing. The culm length, head rice ratio and yield of the selected multi resistance lines was ranged from 71 to 88 cm, from 51 to 93%, from 449 to 629 kg/10a. respectively. We can select a promising multi resistance line similar with 'Nampyeong' of major agronomic traits such as culm legnth, head rice ratio and yield. It was designated as Milyang265. Finally this study was developed the multi resistant varieties against to insects and diseases with the good grain quality 'Milyang265' by the advanced backcross and double cross combining MAS and it can be used as genetic resources of multi-resistance to insect and diseases in rice breeding programs.

• Smart Structures and Systems
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• v.30 no.3
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• pp.327-332
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• 2022

In building envelope, transparent components play an important role. The structural glazing systems are the weak element of the casing in terms of mechanical resistance, thermal and acoustic insulation. In the present work, new structural glass panels with granular aerogel in interspace were investigated from different points of view. In particular, the mechanical characterization was carried out in order to assess the resistance to bending of the single glazing pane. To this end, a special instrument system was built to define an alternative configuration of the coaxial double ring test, able to predict the fracture strength of glass large samples (400 × 400 mm) without overpressure. The thermal and lighting performance of an innovative double-glazing façade with granular aerogel was evaluated. An experimental campaign at pilot scale was developed: it is composed of two boxes of about 1.60 × 2 m² and 2 m high together with an external weather station. The rooms, identical in terms of size, construction materials, and orientation, are equipped with a two-wing window in the south wall surface: the first one has a standard glazing solution (double glazing with air in interspace), the second room is equipped with the innovative double-glazing system with aerogel. The indoor mean air temperature and the surface temperature of the glass panes were monitored together with the illuminance data for the lighting characterization. Finally, a brief energy characterization of the performance of the material was carried out by means of dynamic simulation models when the proposed solution is applied to real case studies.

• Journal of the Korean Electrochemical Society
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• v.16 no.2
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• pp.65-69
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• 2013

In order to improve capacitance of activated carbon for electric double layer capacitors, peptide bond was induced on the surface of the activated carbon by urea. Urea induced activated carbon has been stabilized through carbonization. Electrochemical characteristics was observed by cyclic voltammetry for specific capacitance, electrochemical impedance spectroscope for measuring resistance and charge-discharge for testing the cyclic ability. In the result, specific capacitance is increased about 22.9% than the activated carbon. And it shows excellent cycle performance and decreasing resistance with the introduction of nitrogen functional groups.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.373-377
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• 1999

HTS magnet operated at 20${\sim}$40 K was fabricated using three pieces of 100 m Bi-2223 high temperature superconductors fabricated by powder-in-tube process. It was composed of 6 double pancakes with 75 ID. and 113 OD. connected by lab splice. Coil I$_c$ of each DP.(double pancake) obtained for a 140 turn, fabricated using react and wind procedure was 6${\sim}$8 A at 77 K, self field. The maximum field was measured 0.06 T at lop = 5 A, 77 K. The joint resistance due to lap splice of HTS tapes affect badly to operate HTS magnet with persistent current mode, total effective magnet resistance included lap splice was 55 ${\mu}$ ${\omega}$ at 77 K.

• Steel and Composite Structures
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• v.33 no.6
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• pp.877-889
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• 2019

The developments of double skin composite (DSC) walls with novel enhanced C-channel connectors (DSCW-EC) were reported. Followed axial compression tests on prototype walls were carried to evaluate structural performances of this novel DSC composite structures. The testing program consists of five specimens and focused on the layout of the novel enhanced C-channel (EC) connectors, which include the web direction of C-channels, steel-faceplate thickness, vertical and horizontal spacing of C-channels. Crushing in concrete core and buckling of steel faceplate were two main observed failed modes from the compression tests. However, elastic or plastic buckling of the steel faceplate varies with designed parameters in different specimens. The influences of those investigated parameters on axial compressive behaviors of DSCW-ECs were analyzed and discussed. Recommendations on the layout of novel EC connectors were then given based on these test results and discussions. This paper also developed analytical models for predictions on ultimate compressive resistance of DSCW-ECs. Validation against the reported test results show that the developed theoretical models predict well the ultimate compressive resistance of DSCW-ECs.

• Steel and Composite Structures
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• v.26 no.6
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• pp.759-769
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• 2018

This paper studies shear and tensile behaviors of headed stud connectors in double skin composite (DSC) structure. Firstly, 11 push-out tests and 11 tensile tests were performed to investigate the ultimate shear and tensile behaviors of headed stud in DSC shear wall, respectively. The main parameters investigated in this test program were height and layout of headed stud connectors. The test results reported the representative failure modes of headed studs in DSC structures subjected to shear and tension. The shear-slip and tension-elongation behaviors of headed studs in DSC structures were also reported. Influences of different parameters on these shear-slip and tension-elongation behaviors of headed studs were discussed and analyzed. Analytical models were also developed to predict the ultimate shear and tensile resistances of headed stud connectors in DSC shear walls. The developed analytical model incorporated the influence of the dense layout of headed studs in DSC shear walls. The validations of analytical predictions against 22 test results confirmed the accuracy of developed analytical models.

• Steel and Composite Structures
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• v.37 no.5
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• pp.533-549
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• 2020

Recently, Concrete-filled double skin steel tubular (CFDST) columns have proven an exceptional structural resistance in terms of strength, stiffness, and ductility. However, the resistance of these column members can be severely affected by the type of loading in which bending stresses increase in direct proportion with axial load and eccentricity value. This paper presents a non-linear finite element based modeling approach that studies the behavior of slender CFDST columns under biaxial loading. Finite element models were calibrated based on the outcomes of experimental work done by other researchers. Results from simulations of slender CFDST columns under axial loading eccentric in one direction showed good agreement with the experimental response. The calibrated models are expanded to a total of thirty models that studies the behavior of slender CFDST columns under combined compression and biaxial bending. The influences of parameters that are usually found in practice are taken into consideration in this paper, namely, eccentricity-to-diameter (e/D) ratios, slenderness ratios, diameter-to-thickness (D/t) ratios, and steel contribution ratios. Finally, an analytical study based on current code provisions is conducted. It is concluded that South African national standards (2011) provided the most accurate results contrasted with the Eurocode 4 (2004) and American Institute of Steel Construction (2016) that are found to be conservative. Accordingly, correction factors are proposed to the current design guidelines to provide more satisfactory results.