• Title/Summary/Keyword: high-elasticity

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Vibrational Analysis of Slab Tracks Considering Wheel-Rail Interaction (차륜-레인 상호작용을 고려한 슬래브 궤도의 진동해석)

  • 이희현
    • Computational Structural Engineering
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    • v.7 no.2
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    • pp.77-87
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    • 1994
  • Vibrational analysis of slab tracks for HSR(High Speed Rail) is performed in order to find dynamic characteristics and to control noise and vibration for the tracks. Wheel-rail interactive force is included in the analysis by modelling the vehicle and track as an unsprung mass and elastically-supported-double-beam respectively, and both are assumed to be connected by the Hertzian spring. From this study, it has been found that vibration in the track and the force transmitted to the infrastructure could be reduced by controlling elasticity, mass and stiffness of the track supporting system appropriately.

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Surface Morphology, Microstructure and Mechanical Properties of Thin Ag Films

  • Shugurov, Artur;Panin, Alexey;Chun, Hui-Gon;Oskomov, Konstantin
    • Journal of Powder Materials
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    • v.10 no.3
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    • pp.190-194
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    • 2003
  • Thin Ag films deposited onto $SiO_2/Si$ substrates by DC magnetron sputtering and thereafter annealed ,it temperatures 100-50$0^{\circ}C$ are investigated by scanning tunneling and atomic forte microscopy. It is shown that the film surface topography and microstructure are considerably changed as a result of annealing. To provide a quantitative estimation of the surface topography changes of Ag films the surface fractal dimension was calculated. Elasticity and hardness of the films are studied by a nanoindentation technique. The films are found to have value of elastic modulus close to that of bulk silver while their hardness and yield stress are essentially higher.

PRESENT STATUS OF RICE PRODUCTION AND UTILIZATION IN CHINA

  • Fan, Zhihong
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.13-21
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    • 2003
  • China is the largest rice producer in the world, with about 28 million hectares rice-planting area. Most of the rice is consumed domestically as daily staple food, with a small proportion consumed as feed and deep-processed products. The low elastic elasticity and low profit of rice production which hampers the development of the industry, is due to the low quality of rice grain, low processing level and undeveloped rice processing technique. Promotion of high-quality species, effective quality control, adoption of modem Processing techniques, My use of low-quality indica rice, and utilization of specialty rice are considered as priorities in rice industry.

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Effects of Oil and Sugar on SPI-Tofu Characteristics Under Model System (모델시스템에서 기름과 당이 분리대두단백 두부의 특성에 미치는 영향)

  • 김동원;구경형;최희숙;김우정
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.1
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    • pp.90-97
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    • 1994
  • Effect of addition of oil , sucrose, dextrin and oil-sucrose (1 : 1 w/w) mixture on SPI tofu was investigated. The characteristics measured were yield , water holding capacity , textural and organoleptic properties. THe SPI tofufwas prepared by coagulation of soyprotein isolate (SP) suspensino by CaCl$_2$ , CaSo$_4$ an dGDL , followed by compression . Addition of oil to SPI increased the tofu yield and water holding capacity, particulary for those tofu coagulated by CaCl$_2$. Eventhough dextrin addition decreased the yield, it showed the most improving effect on water holding capacity. The tofu prepared by CaSO$_4$coagulant resulted highest in yield and water holding capacity. Hardness was found to be decreased as the oil, sucrose and dextrin added more and adhesiveness, cohesiveness and guminess were also affected. The sensory evaluation showed the SPI tofu prepared by CaSO$_4$ and 10% addition of oil and sucrose mixture to be realtively high in hardness , elasticity and uniformity of the texture.

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Efficiency Assessment of Crack Maintenance Material Using Ultra Fine Cement (초미립자시멘트를 이요한 균열보수재 성능평가 연구)

  • 백인관;박현수;정란
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.10b
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    • pp.1095-1100
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    • 2000
  • Concrete structure often exhibit cracks due to the combination of material construction and design error. Minor crack can be tolerated depending on exposure condition, but major cracks are aesthetically unpleasant and affect the durability and safety of the structure. All of the reinforced concrete structure have many inevitable cracks for various reason such as drying shrinkage, heat liberation of cement and over loads. Epoxy resin injection widely used for repairing cracks in concrete is too sensitive to high temperature. Besides, the problem in the epoxy resin injection is the difficulty of quality control after execution. Whereas, Ultra Fine Cement is similar in coefficient of thermal expansion and modulus of elasticity to concrete. The objective of the study is to find out that it is possible for Ultra Fine Cement to be used for repairing cracks in reinforced concrete.

Fabrication of R.P.D framework by using Acetal Resin (Acetal resin을 이용한 R.P.D framework의 제작)

  • Kim, Chung-Sook;Park, Myoung-Ho
    • Journal of Technologic Dentistry
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    • v.23 no.1
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    • pp.107-114
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    • 2001
  • R.P.D fabrication can be made if the skills already is properly used in the manufacturing press. You may feel extremely comfortable to wear it. The material used has high elasticity that it can endure the hole process of Acetal Wax pattern casting without any deformation moreover its adaptability is not bad. Because of the poor financial condition of patterns and health insurance, Acetal R.P.D Framework can be one of the best alternatives used for setting clasp partial denture cheaply. R.P.D Framework is aesthetically excellent. The color caused by saliva is so similar to that of the rest of teeth that even dentists as well as patients can not recognize clasp arm. Clasp also helps to secure prosthesis ideally without damaging teeth due to its deep position downward. Since dentists and patients have a good reaction to clasp so far, we are encouraged to apply it to other technical fields.

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Understanding and Practice of Eating-Swallowing Disorder (치과의사 맞춤형 마우스가드의 제작방법)

  • Noh, Kwantae
    • The Journal of the Korean dental association
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    • v.56 no.6
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    • pp.333-338
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    • 2018
  • The mouth guard is a device with elasticity to be installed in the oral cavity. It has a function to reduce the trauma in the oral cavity and to protect the teeth and surrounding tissues from trauma. The purpose of mouth guard is to prevent trauma and concussion. It is mandatory to wear a mouthguard in sports where there is a lot of contact and the possibility of trauma or concussion in the mouth area is high. The mouse guard is divided into a stock type, a mouth formed type, and a custom made type according to the manufacturing method. The custom made type is made on the individual dentition model and has excellent retention because of its excellent fit. Also, the effect of trauma prevention is excellent. It is possible to design and adjust by the dentist and reduce the complaint the athlete has about the mouthguard. In this article, the process of making a dentist-customized mouthguard was described.

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A Study on the Press Forming by Rectangular Tube of Al6063 Alloys (Al6063 합금 중공각재 튜브에 의한 프레스 성형 연구)

  • Lee, Choung-Kook;Kim, Won-Jung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.6
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    • pp.56-62
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    • 2011
  • In this study, a method for the press forming of rectangular aluminium tube has been proposed. Rectangular aluminium tube has high stiff as the cold steel which can be lighter over 30% weight. It is increased every year by being recycled over 80%. Press die consists of punch, wing-die and holder for aluminium tube bending. When punch is applied with aluminium tube, holder is operated as same punch and wing-die is rotated through hinge. Stress-strain relations and springback are considered by bending angle of aluminium tube. In this study, the behaviors on tubes of square aluminium and rectangular aluminium with different thickness and area are established by the analysis of $DEFORM^{TM}$-3D program. Reducing fuel consumption is expected by using the aluminium tube deformation and it becomes the lightweight through recycling.

Prediction of Life Time of Rail Rubber Pad using Reliability Analysis Method

  • Park, Dae-Geun
    • International Journal of Railway
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    • v.6 no.1
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    • pp.13-25
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    • 2013
  • Railpad prevents damage of the tie and ballast by reducing the impact and high frequency vibration, which occurs when a vehicle load transfers to a tie. But elasticity of the railpad can decrease under vehicle load and over usable period. If that happens, railpad will become stiffer. Increase in stiffness of the railpad also translates into a rise in track maintenance cost because it accelerates the damage of the track. In this study, accelerated heat ageing test was performed to predict an expectable lifetime of the railpad. As a result, it was predicted to be about sixteen years at $25^{\circ}C$ that life time of railpad using NR rubber from Arrhenius relationship. Also, it was predicted to be about thirty-two days at $100^{\circ}C$. At this time, a standard rate of thickness change is approximately within 12%.

Volume Pulse Wave Detection System for Oriental Medicine (한방용 용적맥파 시스템)

  • Kim, H.T.;Han, S.C.;Choi, T.J.;Kim, J.K.;Huh, W.;Park, Y.B.
    • Proceedings of the IEEK Conference
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    • 2001.06e
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    • pp.77-80
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    • 2001
  • In this paper, we devised volume pulse detection system which can quantitatively represent a artery elasticity for oriental clinic. Volume pulse wave detecter system consist of transducer which has IRLED-photodiode detecter, temperature sensor and filter and preprocessing circuits, data conversion and serial communication parts, and computer system. The high-pass filter are detect volume pulse wave and lowpass filter detect tissue thickness. The detected volume pulse wave are normalized by tissue thickness value with a division process. As the result of experiment, we can detect normalized volume pulse wave with effectively.

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