• Carbon letters
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• v.17 no.1
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• pp.29-32
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• 2016

This paper addresses the effect of dopants on the electronic properties of zigzag (8, 0) semiconducting single walled carbon nanotubes (SWCNTs), using extended Hückel theory combined with nonequilibrium Green’s function formalism. Through appropriate dopant concentrations, the electronic properties of SWCNTs can be modified. Within this context, we present our ongoing investigation on (8, 0) SWCNTs doped with nitrogen. Quantum confinement effects on the electronic properties of the SWCNTs have also been investigated. The obtained results reveal that the electronic properties of SWCNTs are strongly dependent on the dopant concentration and modification of electronic structures by hydrogen confinement.

• Computers and Concrete
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• v.19 no.6
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• pp.677-687
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• 2017

The nonlinear buckling response of nano composite anti-symmetric functionally graded polymeric microplate reinforced by single-walled carbon nanotubes (SWCNTs) rested on orthotropic elastomeric foundation with temperature dependent properties is investigated. For the carbon-nanotube reinforced composite (CNTRC) microplate, a uniform distribution (UD) and four types of functionally graded (FG) distribution are considered. Based on orthotropic Mindlin plate theory, von Karman geometric nonlinearity and Hamilton's principle, the governing equations are derived. Generalized differential quadrature method (GDQM) is employed to calculate the non-linear buckling response of the plate. Effects of FG distribution type, elastomeric foundation, aspect ratio (thickness to width ratio), boundary condition, orientation of foundation orthotropy and temperature are considered. The results are validated. It is found that the critical buckling load without elastic medium is significantly lower than considering Winkler and Pasternak medium.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.17-21
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• 2002

A finite element method based on the two-dimensional progressive failure analysis is presented for characterizing the strength and failure of the unidirectional-fabric hybrid laminated composite joints under pin loading. The 8-node laminated shell element is incorporated in the updated Lagrangian formulation. Various failure criteria including the maximum stress, Tsai-Wu, Yamada-Sun, and combinations of them are used in conjunction with the complete unloading stiffness degradation method. For the verification, joint tests are conducted for the specimens with various geometries. Although there are some differences depending on the geometry, the finite element model using the Yamada-Sun or the combined Yamada-Sun and Tsai-Wu criterion predicts the failure strength best.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.97-100
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• 2004

This paper introduced an artificial fault generator which was operated in the Go-Chang field-test center and explained the result of single line-to-ground fault by AFG. The AFG can basically experiment line-to-line and line-to-ground faults. This facility directly connected distribution transmission lines, so the test results are very useful for power system analysis and protection. Using the function of the AFG, we briefly said the test methods ud results for the 22.9[kV-v] and $6.6[kV-{\Delta}]$ system.

• Annual Conference on Human and Language Technology
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• 2018.10a
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• pp.334-339
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• 2018

본 논문에서는 기존에 구축되어 있는 구 구조 기반 구문 분석 태그셋을 Universal Dependency 관계 태그 셋으로 변환하는 방안에 대해 논의하였다. 범언어적으로 활용하기 위해 개발된 Universal Dependency의 관계 태그셋을 한국어에 적용할 때에는 범용 POS 태그셋인 UPOS뿐만 아니라 개별 언어의 특성을 반영하고 있는 XPOS를 반드시 참고해야만 한다. 본 연구에서는 Universal Dependency 관계 태그셋을 한국어 구문 분석 태그셋에 대응시키는 과정에서 생기는 문제점들을 '원시 말뭉치 처리 문제'와 '기구축 구문 태그 말뭉치 오류의 문제'로 나누어 지적하고, 이에 대한 해결책을 제시하였다.

• Journal of the Ergonomics Society of Korea
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• v.10 no.1
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• pp.3-10
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• 1991

The teach pendant and keyboard have been used as an input device of control command in human-robot sustem. But, many problems occur in case that the usef is a novice. So, speech recognition system is required to communicate between a human and the robot. In this study, Korean voice commands, eitht robot commands, and ten digits based on the broad phonetic analysis are described. Applying broad phonetic analysis, phonemes of voice commands are divided into phoneme groups, such as plosive, fricative, affricative, nasal, and glide sound, having similar features. And then, the feature parameters and their ranges to detect phoneme groups are found by minimax method. Classification rules are consisted of combination of the feature parameters, such as zero corssing rate(ZCR), log engery(LE), up and down(UD), formant frequency, and their ranges. Voice commands were recognized by the classification rules. The recognition rate was over 90 percent in this experiment. Also, this experiment showed that the recognition rate about digits was better than that about robot commands.

• Korean Journal of Child Studies
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• v.28 no.2
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• pp.137-153
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• 2007

This research studied differences in the distribution of maternal attachment representation between divorced and non-divorced low income mothers, associations between their divorce and childhood experiences, and associations between maternal attachment representation and childhood experiences. Subjects were twenty each divorced and still-married women with low socioeconomic status. The Adult Attachment Interview was used to assess their attachment representation resulting in classification by four types; autonomous (F), dismissing (Ds), preoccupied (E), or unresolved/disorganized (Ud). The divorced women had more childhood experiences of being rejected and neglected by their mothers than the non-divorced women. This indicates that maternal childhood experiences were related to maternal attachment representation and divorce.

• Journal of the Korean Mathematical Society
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• v.45 no.1
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• pp.29-40
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• 2008

In this paper, we introduce a modified three-step iteration scheme with errors for three classes of uniformly equi-continuous and asymptotically quasi-nonexpansive mappings in the framework of uniformly convex Banach spaces. We then use this scheme to approximate a common fixed point of these mappings. The results obtained in this paper extend and improve the recent ones announced by Khan, Fukhar-ud-di, Zhou, Cho, Noor and some others.

• Composites Research
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• v.12 no.5
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• pp.80-86
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• 1999

Mechanical characteristics of composite laminates and cylindrical shell using scrim of glass scrim are evaluated in this paper. Composite laminates and cylindrical shells are made by inserting carbon scrim or glass scrim between layers. The mechanical properties are routinely characterized by ASTM stands. Experimental results show that the mechanical properties of UD prepreg in the transverse direction are highly improved by inderting scrims between layers.

• Journal of Pharmaceutical Investigation
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• v.24 no.2
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• pp.105-108
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• 1994

The ulcerogenic activity of a 3% ketoprofen gel (ID-GEL) after its transdermal application in rats was determined with the Litchfield and Wilcoxon method in reference to the oral administration of ketoprofen in a suspension. The $UD_{50}$ (dose producing ulcers in 50%, of the rats tested) of ID-GEL after its transdermal application was approximately 4 times greater than that after the oral administration of the drug, indicating that the ulcerogenic activity of ketoprofen was much lowered with its transdermal application.