• Title/Summary/Keyword: useful material

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Why Did They Choose ICT Materials?

  • Heo, Shin-hye
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.47-51
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    • 2022
  • The purpose of this study is to investigate the views on utilizing ICT material, especially the reasons for ICT material choice. Numerous recent studies have demonstrated increased use of electronic devices including smartphones in educational settings. But the reasons for using it as a learning tool have not been relatively researched from the point of view of pre-service teachers. Therefore, this study analyzed the pre-service teachers' thinking about utilizing ICT material and their learning experience. In that regard, data was collected in various ways such as surveys, interviews, and brief writings of participants. According to the study result, pre-service teachers were motivated in utilizing ICT material rather than text material. That is the reason why, as adult learners, especially pre-service teachers could be more motivated in self-directed learning environments. This study will be useful in considering ideas for the instructional design of pre-service teachers.

Press forming severity analysis and selection of optimum sheet steel properties for customer lines by using 3-D simulation program. (삼차원 프레스가공 시뮬레이션 기술을 활용한 수요가 가공공정 분석과 최적 재질선정)

  • 박기철;한수식
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1996.06a
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    • pp.111-131
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    • 1996
  • In order to analyze stamping processes and to select optimum material properties of sheet steels for customer lines, 3-dimensional finite element analysis software were used. Commercial explicit finite element code, PAM-STAMP, was able to simulate 3-dimensional press formed parts with good accuracy and gave some useful results by orthogonal array experiments. Deformation of draw-bead were predicted by ABAQUS accurately, so that material selection for those parts by simulation were possible.

A Study on the Calculation of Escape Frequency Factor using TSC Equation (열자격전류식을 이용한 이탈주파수인자 계산에 관한 연구)

  • 김기준;김상진;전동근
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.135-138
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    • 1995
  • This paper presents a method to calculate the escape frequency factor and its verification from TSC(Thermally Stimulated Current) equation and cures. To apply calculation method of ν using asymptotic estimation, it utilized two sets of TSC data with 1K interval. This method enables one to get the exact value of ν and activation energy at the same time by using computer programming. So, it regards their calculation method as a useful process to obtain the value of physical behavior.

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Analysis of transport properties of SLS polysilicon TFTs

  • Fortunato, G.;Bonfiglietti, A.;Valletta, A.;Mariucci, L.;Rapisarda, M.;Brotherton, S.D.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.513-518
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    • 2006
  • An investigation of the transport properties of polysilicon TFTs, using sequential laterally solidified, SLS, material, is presented. This material has a location controlled distribution of grain boundaries, GBs, which makes it particularly useful for the analysis of their influence on the performance of polysilicon TFTs, and to address the issue of the role of spatially localised trapping states. The experimental results were analyzed by using numerical simulations, and the effective medium approximation was compared with a discrete grain model.

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Computation of Equivalent Material Properties of Woven Fabric Composites Using Homogenization Technique (균질화기법을 이용한 WFC의 등가물성치 산출)

  • 이진희;장지현;윤민우
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1997.10a
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    • pp.1-7
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    • 1997
  • Equivalent thermal conductivities and elasticity properties of woven fabric composites are computed using homogenization technique. The computational results show that the strength and thermal conductivity linearly increase with fiber volume fraction and that the variations of undulation of fibers has little effect on equivalent material properties. Homogenization technique is proved useful in the study of woven fabric composites and may find a lot more applications in the area.

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Structural analysis of Aluminium coach body (알루미늄 객차의 구조강도 해석)

  • 이정수;서승일;이기열
    • Proceedings of the KSR Conference
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    • 1998.11a
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    • pp.583-588
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    • 1998
  • Large extrusions of aluminium alloy can be more general and useful as structural material of rolling stocks to reduce weight and labor cost than mild steel and stainless steel. Our company is studying aluminium coach body will be made of 6005A and A5083 alloy. In this paper, at first detailed finite element analysis is carried out to calculate the orthotropic material properties of aluminium extrusions. And then global strength evaluation of coach body is carried out according to UIC 566 OR code.

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A New Material for Rapid and Easy Method of Plant Surface Imprinting

  • Bhat, R.B.;Etejere, E.O.
    • Journal of Plant Biology
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    • v.28 no.4
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    • pp.329-332
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    • 1985
  • A simple new device for obtaining very clear epidermal imprints for light microscopic studies is discussed. This new device is developed from“Britfix”(polystyrene cement) which is non-toxic to the plant organs. It involves direct application of the material on the desired surface of the plant organ to obtain thin, transparent replica. From the present investigation“Britfix”is found to be useful for the study of epidermal anatomy, morphology and physiology. Epidermal imprints can be mounted on the microscope slide without a mounting medium. Permanent slide of these imprints can be kept for any desired period without any deterioration of the replica.

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Acoustic Control of Optional Space Using Optimum Location of Absorbing Material (흡음재 최적배치를 이용한 임의 공간의 음향제어에 관한 연구)

  • 김동영;홍도관;안찬우
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.10
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    • pp.1048-1054
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    • 2004
  • The Passive acoustic control is used in various fields, such as structures, automobiles, aircraft and so on. It is used in variety of acoustic field with the absorbing material, as one of the methods which can control the acoustic in optional space. In that case of passive control using this absorption material, it would be important to maximize the control performance of material property, numbers, geometry shape and the attached location of boundary area of the absorbing material. But realistically these variables, specially material Property, have no broad choice. Therefore, the position of absorbing material is the most important variable. In this study, we use the optimization method to minimize acoustic energy of optional space in the interest frequency attaching some absorbing materials to the boundary area. For analysis and optimization, this study uses the FEA and the conjugate gradient method. This optimization process is very efficient and useful in the passive acoustic control.

AHP-Based Evaluation Model for Optimal Selection Process of Patching Materials for Concrete Repair: Focused on Quantitative Requirements

  • Do, Jeong-Yun;Kim, Doo-Kie
    • International Journal of Concrete Structures and Materials
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    • v.6 no.2
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    • pp.87-100
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    • 2012
  • The process of selecting a repair material is a typical one of multi-criteria decision-making (MCDM) problems. In this study Analytical Hierarch Process was applied to solve this MCDM problem. Many factors affecting a process to select an optimal repair material can be classified into quantitative and qualitative requirements and this study handled only quantitative items. Quantitative requirements in the optimal selection model for repair material were divided into two parts, namely, the required chemical performance and the required physical performance. The former is composed of alkali-resistance, chloride permeability and electrical resistivity. The latter is composed of compressive strength, tensile strength, adhesive strength, drying shrinkage, elasticity and thermal expansion. The result of the study shows that this method is the useful and rational engineering approach in the problem concerning the selection of one out of many candidate repair materials even if this study was limited to repair material only for chloride-deteriorated concrete.

Effect of Side Groove on the Elastic Plastic Fracture Toughness of Gas Piping Material (가스배관재의 탄소성파괴인성에 미치는 측면홈 영향)

  • 임만배;차귀준;윤한기;공유식;김정호
    • Journal of Ocean Engineering and Technology
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    • v.15 no.3
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    • pp.63-68
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    • 2001
  • SG-365 steel is an important material and used for manufacturing a pressure vessel which the gas piping. In this investigation, the elastic plastic fracture toughness of this material is evaluated by the an unloading compliance method according to the ATM E813-97 method on the smooth and side groove 1CT specimens. The effect of smooth and side groove is studied on the elastic plastic fracture toughness. The side grooved specimen is very useful in estimation of the $J_IC. Because it is much easier than the smooth specimen to the onset of the ductile tearing by the R curve method. Besides, it improves the accuracy of toughness values, decreases the scattering of them and tunneling and shear lip by the side groove.

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