• Title/Summary/Keyword: Soft Surface

검색결과 970건 처리시간 0.031초

침하량과 과잉간극수압을 이용한 압밀도의 추정 (Estimation of the Degree of Consolidation using Settlement and Excess Pore Water Pressure)

  • 이달원;임성훈
    • 한국농공학회지
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    • 제44권3호
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    • pp.111-121
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    • 2002
  • This study was performed to estimate the degree of consolidation using excess pore water pressure in the very soft ground. The final settlement prediction methods by Hyperbolic, Asaoka and Curve fitting methods from the measured settlement data were used to compare with the degree of consolidation estimated by excess pore water pressure. The dissipated excess pore water pressure during embankment construction and the peak excess pore water pressure on the completed embankment were used for the estimation of the degree of consolidation. After completion of embankment, it was concluded that the degree of consolidation estimated from dissipated excess pore water pressure was more reliable than that from the peak excess pore water pressure. And, the degree of consolidation estimated from the surface settlement was nearly the same as settlement of each layer. The degree of consolidation estimated from dissipated excess pore water pressure was a little larger than that from settlement.

Growth of magnesium oxide nanoparticles onto graphene oxide nanosheets by sol-gel process

  • Lee, Ju Ran;Koo, Hye Young
    • Carbon letters
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    • 제14권4호
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    • pp.206-209
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    • 2013
  • Nanocomposites comprised of graphene oxide (GO) nanosheets and magnesium oxide (MgO) nanoparticles were synthesized by a sol-gel process. The synthesized samples were studied by X-ray powder diffraction, atomic force microscopy, transmission electron microscopy, and energy-dispersive X-ray analysis. The results show that the MgO nanoparticles, with an average diameter of 70 nm, are decorated uniformly on the surface of the GOs. By controlling the concentration of the MgO precursors and reaction cycles, it was possible to control the loading density and the size of the resulting MgO particles. Because the MgO particles are robustly anchored on the GO structure, the MgO/GOs nanocomposites will have future applications in the fields of adsorption and chemical sensing.

Effect of Elastic Modulus Mismatch on the Contact Crack Initiation in Hard Ceramic Coating Layer

  • Lee, Kee-Sung
    • Journal of Mechanical Science and Technology
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    • 제17권12호
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    • pp.1928-1937
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    • 2003
  • Effect of elastic modulus mismatch on the contact crack initiation is investigated to find major parameters in designing desirable surface-coated system. Silicon nitride coated soft materials with various elastic modulus mismatch, E$\_$c//E$\_$s/=1.06∼356 are prepared for the analysis. Hertzian contact test is conducted for producing contact cracks and the acoustic emission detecting technique for measuring the critical load of crack initiation. The implication is that coating thickness and material strength are controllable parameters to prevent the initiation of contact cracks resulted from the elastic modulus mismatch in the hard ceramic coating layer on the soft materials.

모형토조시험을 통한 준설매립토의 건조특성에 관한 연구 (Desiccation Characteristics of Dredged Soft Clay by Large Model Test)

  • 정하익;오인규;지성현;이승원;이영남
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.591-596
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    • 2001
  • The purpose of this paper Is to present and discuss some of evaporation and desiccation observed in laboratory experiments under controlled conditions, and is to improve PTM(Progressive Trenching Method) operating technique. PTM is the technically feasible and economically justifiable dewatering and desiccation technique for dredged material containment areas. A series of laboratory experiments with large model test were carried out to get evaporation rate and strength increase. Surface desiccation of dredged material is basically changed by evaporation characteristics which is controlled by weather and trench type, etc. This study shows that trench depth and rain fall are important factors in desiccation of dredged soft clay.

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폴리염화비닐에 방사선 조사시의 저항의 변화와 가소제의 영향 (A study for the changer of resistance and influence of the dioctylphthalate by irradiation on the polyvinyl chloride)

  • 신종원;백용현
    • 전기의세계
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    • 제30권10호
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    • pp.639-644
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    • 1981
  • PVC is a kind of electric insulation polymer. But we get some deteriorations in electrical characteristics of the PVC, when it is used on the radioactive field. In order to find out the cause of the deterioration, we investigate the surface-resistance, volume-resistance, dielectric constant and dielectric loss angle of the soft and hard PVC which is irradiated by the Co$^{60}$ .gamma. radioactivity. From the experiment, we can conclude the followings 1. Radio-activity proof characteristic in the soft PVC is stronger than in the hard PVC. 2. The resistance of PVC which is irradiated by the radio-activity decrease exponentially. 3. The dielectric constant and the dielectric loss angle of PVC irradiated by Co$^{60}$ .gamma.ray reach maximum value in first few time.

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막 구조물의 측지선을 이용한 재단도 생성에 관한 연구 (A Study on Cutting Pattern Generation of Membrane Structures by Using Geometric Line)

  • 안상길;손수덕;김승덕
    • 한국공간구조학회:학술대회논문집
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    • 한국공간구조학회 2005년도 춘계학술발표회 및 정기총회 2권1호(통권2호)
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    • pp.125-132
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    • 2005
  • Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The material property of the membrane has strong axial stiffness, but little bending stiffness. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation. In shape finding, membrane structures are unstable structures initially. These soft structures need to be introduced initial stresses because of its initial unstable state, and it happens large deformation phenomenon. And also there are highly varied in their size, curvature and material stiffness. So, the approximation inherent in cutting pattern generation methods is quite different. Therefore, in this study, to find the structural shape after large deformation caused by Initial stress, we need the shape analysis considering geometric nonlinear ten And the geodesic line on surface of initial equilibrium shape and the cutting pattern generation using the geodesic line is introduced.

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나노초 및 펨토초 레이저를 이용한 젤라틴의 미세가공 (Processing of gelatin using nanosecond and femtosecond pulsed lasers)

  • 서창호;안대환;김동식
    • 한국레이저가공학회지
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    • 제15권2호
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    • pp.1-5
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    • 2012
  • Gelatin is used as a model for soft biological tissues in studying laser interaction with the soft tissues. In this work, we analyze the interaction between gelatin and excimer and Ti:Sapphire femtosecond laser under various conditions, especially by varying the laser, laser fluence and pulse number. The results show that swelling of the surface and ablation depth can be controlled by adjusting the process parameters.

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Soft-lithography for Preparing Patterned Liquid Crystal Orientations

  • Kim, Hak-Rim;Jung, Jong-Wook;Shin, Min-Soo;Kim, Myung-Eun;Lee, You-Jin;Kim, Jae-Hoon
    • Journal of Information Display
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    • 제8권2호
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    • pp.5-9
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    • 2007
  • We demonstrate novel soft-lithographic techniques for preparing patterned liquid crystal (LC) orientations at an alignment layer. By controlling patterning conditions such as wetting property and operating temperature depending on polymeric materials, multi-directional or modified LC alignment conditions can be simply achieved.

Magnetic Properties of Amorphous FeSiB and Nanocrystalline $Fe_{73}Si_{16}B_7Nb_3Cu_1$ Soft Magnetic Sheets

  • Cho, H.J.;Cho, E.K.;Song, Y.S.;Kwon, S.K.;Sohn, K.Y.;Park, W.W.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.786-787
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    • 2006
  • The magnetic inductance of nanocrystalline $Fe_{73}Si_{16}B_7Nb_3Cu_1$ and an amorphous FeSiB powder sheet has been investigated to identify RFID performance. The powder was mixed with binder and solvent and tape-casted to form films. Results show annealing significantly influenced on the inductance of the material. The surface oxidation of the particles was the main reason for the reduced inductance. The maximum inductance of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ alloy was about $88{\mu}H$ at 17.4 MHz, about 65% greater compared to the FeSiB alloy. The higher inductance in the nanocrystalline alloy indicates it may be used as a potential replacement of current RFID materials.

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전자적 장세척을 위한 부드러운 장표면 복원 방법 개발 (Development of a Smooth Colon Surface Restoration Method for Electronic Colon Cleansing)

  • 김승환;김동성
    • 대한의용생체공학회:의공학회지
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    • 제32권3호
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    • pp.251-256
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    • 2011
  • Virtual colonoscopy is favored over conventional colonoscopy because its non-invasive procedure can avoid complications that may happen in a conventional approach and because it can cleanse colon electronically instead of uncomfortable conventional colon cleansing. Electronic Colon Cleansing(ECC) has to deal with not only removing tagged fecal material but also recovering Partial Volume Effect(PVE) due to tagging material. This paper proposes an ECC method restoring inherent natural PVE while previous approaches focused only on reducing PVE due to tagged fecal material. The proposed method reduces PVE using 3-dimensional adaptive density correction and then replaces tagged fecal material into air. Next, it generates natural PVE for the replaced air adjacent to soft tissue and finally makes smooth transition of gray values for soft tissue adjacent to the replaced air. The proposed method applied to eleven patient data, and showed promising results.