• Journal of Electrical Engineering and Technology
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• 제13권3호
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• pp.1355-1362
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• 2018

In order to obtain a better understanding of the ageing process of the field composite insulators, it is necessary to explore a quantitative-valuation method for the aging state evaluation. And the linear relationship between volume resistivity and temperature is proposed. In this paper, the composite insulators with different lengths of operating lives from two manufacturers were tested. The relationship between trap characteristics and volume resistivity-temperature characteristics were analyzed based on Thermal Stimulated Current (TSC), volume resistivity-temperature test, Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Furthermore, the application of trap characteristics in the quantitative evaluation of aging state of composite insulators was discussed. The results showed that there was a general negative correlation between the relative variation ratio of trap charges and the volume resistivity-temperature characteristics. Meanwhile, the physicochemical properties would change with the aging time, which would result in the increasing of electron traps. Combined with the TSC and volume resistivity test results, the trap characteristic thresholds which indicated the serious age of the composite insulators had been proposed.

• Computers and Concrete
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• 제23권4호
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• pp.295-301
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• 2019

In this paper, buckling analyses of composite concrete plate reinforced by piezoelectric nanoparticles is studied. The Halphin-Tsai model is used for obtaining the effective material properties of nano composite concrete plate. The nano composite concrete plate is modeled by Third order shear deformation theory (TSDT). The elastic medium is simulated by Winkler model. Employing nonlinear strains-displacements, stress-strain, the energy equations of concrete plate are obtained and using Hamilton's principal, the governing equations are derived. The governing equations are solved based on Navier method. The effect of piezoelectric nanoparticles volume percent, geometrical parameters of concrete plate and elastic foundation on the buckling load are investigated. Results showed that with increasing Piezoelectric nanoparticles volume percent, the buckling load increases.

• 한국동물위생학회지
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• 제27권3호
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• pp.249-256
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• 2004

The Korea chinese chives are a major edible vegetable and they are traditionally been used as a folk medicine. However recently studies on the Allium tuberosum are mainly on the morphological property and the chemical constituent. There are no reports concerning hematological changes in dogs administrated ethyl acetate extracts of Korea chinese chive. This experiment was conducted to investigate the hematological changes in dogs administrated ethyl acetate extracts of the Korea chinese chives($5m{\ell}/mg$) for 6 days. During administration blood samples were collected at 3h, 6h, 12h and then on daily basis until day 6. Blood samples were analyzed red blood cell(RBC), packed cell volume(PCV), hemoglobin concentration(Hb), mean corpuscular volume(MCV), mean corpuscularl hemoglobin concentration(MCHC), reduced glutathion(GSH), and met-hemoglobin concentration. The RBC count was significantly(p<0.01, p<0.05) decreased during experimental periods. Packed cell volume, hemoglobin concentration were not showed significantly difference during experimental periods. The MCV was significantly(p<0.01, p<0.05) increased from 3 hours after administration to day 4. The MCHC was significantly(p<0.05)decreased on day 6. GSH concentration was not showed significant difference during experimental periods and the met-hemoglobin concentration was significantly(p<0.05) increased on day 3.

• 소성∙가공
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• 제10권1호
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• pp.23-29
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• 2001

In this study, the optimized initial hole shape for T-branch forming was proposed to obtain effective welding region. Design variables were determined by approximation analysis using volume constant condition. We performed 3D elastic-plastic FEM(Finite Element Method) analysis to simulate T-branch forming process. The variation of height and thickness of T-branch with various hole shapes was investigated. The optimized initial hole shape equation was obtained by using results for the numerical analysis.

• 대한기계학회논문집
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• 제18권10호
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• pp.2762-2772
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• 1994

Branch flows for Newtonian and non-Newtonian fluids are simulated by the finite volume method. The modified power-law model is employed as a constitutive equation of the non-Newtonian fluids. Numerical analyses are focused on understanding of flow patterns for different values of branch angles, diameter ratios and Reynolds numbers. The numerical results are compared with the existing experimental data. The calculated velocity profiles and pressure variations are in good agreement with available experimental results.

• 디지털융복합연구
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• 제18권9호
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• pp.391-402
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• 2020

오늘날은 미디어 컨버전스 시대로 게임처럼 스토리를 선택하는 드라마를 시청하거나 영화처럼 연출하는 게임을 즐길 수 있다. 두 매체는 인터랙티브 스토리텔링을 구현하고 있으며 이 대한 논의는 오래전부터 현재까지 진행 중이다. 본 연구는 인터랙티브 스토리텔링의 새로운 브렌치 구조를 제안함과 동시에 브렌치 구조 스토리텔링 진행 방법에 대한 새로운 관점을 모색함을 목적으로 한다. 지금까지 인터랙티브 스토리텔링을 가장 잘 구현하고 있는 게임을 주된 연구대상으로 하였으며 연구결과 스토리의 내러티브를 유지하면서도 이용자가 자유롭게 상호작용을 느낄 수 있는 인터랙티브 스토리텔링 구조로서 Plot border와 Adjuster 개념을 포함한 Volume 브렌치 구조를 제안하였다. 이 구조는 게임매체 속에서 실시간 편집 영상으로만 구현할 수 있으며 지속적으로 발전하고 있는 물리엔진과 현재까지 게임에는 적극 도입되지 않고 있는 인공지능을 적용할 때 가능함을 설명하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권9호
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• pp.2232-2245
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• 2013

The present study proposes efficient procedural modeling methods for enabling the growth and creation of various trees with minimal user control. Growth volume algorithms are utilized in order to easily and effectively calculate many parameters that determine tree growth, including branch propagation. Procedural methods are designed so that users' interactive control structures can be applied to these algorithms to create unique tree models efficiently. First, through a two-line-based interactive growth volume control method, the growth information that determines the overall shape of the tree is intuitively adjusted. Thereafter, independent branch control methods designed to control individual branches are added to the growth deformation in order to enable the growth of unique trees. Whether the growth processes of desired trees can be easily and intuitively controlled by the proposed method is verified through experiments. Methods that can apply the proposed methods are also verified.

• Earthquakes and Structures
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• 제15권3호
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• pp.285-294
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• 2018

In this study, nonlinear dynamic response of a concrete plate retrofit with Aluminium oxide ($Al_2O_3$) under seismic load and magnetic field is investigated. The plate is a composite reinforced by Aluminium oxide with characteristics of the equivalent composite being determined using Mori-Tanka model considering agglomeration effect. The plate is simulated with higher order shear deformation plate model. Employing nonlinear strains-displacements, stress-strain, the energy equations of column was obtained and using Hamilton's principal, the governing equations were derived. Differential quadrature method (DQM) in conjunction with Newark method is applied for obtaining the dynamic response of structure. The influences of magnetic field, volume percent of nanoparticles, geometrical parameters of column, agglomeration and boundary conditions on the dynamic response were investigated. Results showed that with increasing volume percent of nanoparticles, the dynamic deflection decreases.

• Computers and Concrete
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• 제21권5호
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• pp.569-582
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• 2018

In this study, nonlinear vibration and stability of a polymeric pipe reinforced by single-walled carbon naotubes (SWCNTs) conveying fluid-nanoparticles mixture flow is investigated. The Characteristics of the equivalent composite are determined using Mori-Tanaka model considering agglomeration effects. The surrounding elastic medium is simulated by orthotropic visco-Pasternak medium. Employing nonlinear strains-displacements, stress-strain energy method the governing equations were derived using Hamilton's principal. Differential quadrature method (DQM) is used for obtaining the frequency and critical fluid velocity. The influence of volume percent of SWCNTs, agglomeration, geometrical parameters of pipe, viscoelastic foundation and fluid velocity are shown on the frequency and critical fluid velocity of pipe. Results showed the increasing volume percent of SWCNTs leads to higher frequency and critical fluid velocity.

• Advances in concrete construction
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• 제7권1호
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• pp.51-63
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• 2019

The project focuses on the dynamic analysis of concrete beams reinforced with silica-nanoparticles under blast loading. The structure is located at two boundary conditions. The equivalent composite properties are determined using Mori-Tanak model. The structure is simulated with sinusoidal shear deformation theory. Employing nonlinear strains-displacements, stress-strain, the energy equations of beam were obtained and using Hamilton's principal, the governing equations were derived. Using differential quadrature methods (DQM) and Newmark method, the dynamic deflection of the structure is obtained. The influences of volume percent and agglomeration of silica nanoparticles, geometrical parameters of beam, boundary condition and blast load on the dynamic deflection were investigated. Results showed that with increasing volume percent of silica nanoparticles, the dynamic deflection decreases.