• Title/Summary/Keyword: 화후

Search Result 23, Processing Time 0.02 seconds

Estimation of the Permeability Variation in Saturated Sand Deposits Subjected to Shaking Load Using 1-g Stinking Table Test (1-g 진동대시험을 이용한 진동하중을 받는 포화된 모래지반의 투수계수 변화 추정)

  • 하익수;김명모
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.6
    • /
    • pp.363-369
    • /
    • 2003
  • The purpose of this study is to understand the dissipation pattern of excess pore pressure after liquefaction and to estimate the variation in permeability during shaking load, which should be known for settlement predictions of the ground undergoing liquefaction. In this study, 1-g shaking table tests were carried out for 5 different kinds of sands, all of which had high liquefaction potentials. During the tests excess pore pressure at various depths, and surface settlements were measured. The measured dissipation curve of the excess pore pressure after liquefaction was linearly simulated using the solidification theory, and from the analysis of the slopes of linearly simulated curves, the correlation between dissipation velocity and the gradation characteristics was obtained. By substituting this correlation and the measured settlement to the dissipation velocity equation recommended in solidification theory, the permeability during dissipation was calculated, which was used for estimating the permeability variation during shaking load. The dissipation velocity of excess pore pressure after liquefaction had a linear correlation with the effective grain size divided by the coefficient of uniformity. The permeability during dissipation and liquefaction increased by 1.1∼2.8 times and 1.4∼5 times compared to the initial permeability of the original ground, respectively. And the amount of increase became greater as the effective grain size of the test sand increased and the coefficient of uniformity decreased.

A study of Luminescence effects of POF-woven Fabric Display by Method of Weaving (직물화 방식에 따른 유연 광섬유 직물 디스플레이의 광원 색채별 발광효과에 관한 연구)

  • Yang, Jin-Hee;Park, Sun-Hyung;Cho, Hyun-Seung;Lee, Joo-Hyeon
    • Science of Emotion and Sensibility
    • /
    • v.16 no.4
    • /
    • pp.517-526
    • /
    • 2013
  • This paper reports on flexible plastic optical fiber (POF) fabric displays which are used to develop light-emitting clothing from photonic fabric. We first evaluated the luminescence value corresponding to different methods of processing flexible optical fibers, types of reflective fabric structure, and colors of the light. Moreover, we tried to identify the optimum conditions of the flexible POF fabric displays to realize high luminescence value. The processing methods that were compared were the "Pre-etching" method and the "Post-etching" method. On the basis of the reflective structure of the fabric, the fabrics were categorized as the "White fabric" and the "Reflective fabric." Analysis results showed that the effect of the processing method is more dominant than that of the types of reflective fabric structure. Further, the capability of the Post-etching method to increase luminescence value is slightly higher than that of the Pre-etching method. Further, the 'Reflective fabric' is slightly more efficacious as the base fabric to increase the luminescence value, than the White fabric is. Thus, optimum increase in luminance can be realized by employing the Post-etching method and the Reflective fabric as the base fabric.

Multiple Car Plate Detection (다중 번호판 영역 검출)

  • 강동구;이상훈;김경현;차의영
    • Proceedings of the Korea Multimedia Society Conference
    • /
    • 2002.05c
    • /
    • pp.361-364
    • /
    • 2002
  • 번호판 인식 시스템은 일반적으로 한 차선에 한 카메라를 사용한다. 만약 2개의 차로를 동시에 촬영하도록 카메라를 설치한다면 시스템 구축 비용이 많이 감소할 것이다. 본 논문은 이러한 시스템의 구축에 필요한 기본적인 방법으로써 이미지에서 번호판이 2개 이상 존재할 경우에도 그 위치를 모두 검출할 수 있는 방법에 대하여 제안한다. 번호판 후보 영역 추출은 모폴로지 연산을 통해 검출하고 각 후보 영역은 이진화후 제안한 검증 방법을 통해 후보 영역을 제거하고 번호판인 후보 영역에 대하여 정확한 번호판 영역을 검출한다. 제안한 검출 방법은 일반 번호판과 영업용 번호판 모두 검출할수 있다.

  • PDF

A Study on The Waitan Alchemy method of Peng Xiao's 'Zhouyi chantongqi fenzhangtongzhenyi' (팽효 『주역참동계분장통진의』의 외단 연단법 연구)

  • 신진식
    • 유학연구
    • /
    • v.44
    • /
    • pp.303-333
    • /
    • 2018
  • In this paper, Peng Xiao's analysis of his Waitan Alchemy method was conducted, using Zhouyi Chantongqi Fenzhangtongzhenyi as the main text. Unlike former President Zhouyi Chantongqi, Peng Xiao's president Zhoui Chantongqi is characterized by the simultaneous appearance of Neidan and Waitan. It reveals the characteristics of the course. The study of Zhouyi Chantong qi Fenzhangtongzhenyi explains the shift in Waitan and Neitan in Taoism and the change in terms of its meaning and terminology. In this paper, we looked at the basic principles of Alchemy in Zhouyi Chantongqi Fenzhangtongzhenyi, the three main tools of Alchemy : pots, drugs, and fire control. In addition, Huangtan, Liangtan and Xuantan, which were acquired in the specific process of Alchemy, were also identified through text analysis. Finally, we looked at the effects and effects of the Waitan's Alchemy. These studies will provide easier access to the Waitan language, which is more diverse than the original Wei Boyang's Zhouyi Chantongqi and other comments. Based on this, another in-depth study of the Neitan idea of Fenzhangtongzhenyi will be possible in the future.

The Study on the Strengthening of $Li_2O-AI_2O_3-SiO_2$ Glass-Ceramics by Ion Exchange (LAS계 결정화유리의 화학적강화에 관한 연구)

  • Jang, Pil-Sun;Gang, Won-Ho
    • Korean Journal of Materials Research
    • /
    • v.6 no.4
    • /
    • pp.364-371
    • /
    • 1996
  • 본 연구는 이온교환에 의한 Li2O-AI2O3 계 결정화유리의 강화에 관한 연구이다. 모유리의 이온교환 전후의 강도를 비교하였으며, 결정화유리의 결정화전후에 이온교환에 따르는 강도를 상호 비교하였다. 그 결과 모유리의 Na+이온교환에 따른 최대 강도값은 45$0^{\circ}C$-3hr의 열처리 조건하에서 최고 6배(60Kg/mm2)의 강도값을 나타내었으며, 결정화후 이온교환에 따른 강도증가는 45$0^{\circ}C$-1hr의 열처리 조건하에서 최고 10배의 강도증대효과를 보였다. 한편 과도한 이온교환 열처리조건하에서는 응력이완현상을 나타냄을 알 수 있었다.

  • PDF

Dissipation Pattern of Excess Pore Pressure after Liquefaction in Saturated Sand Deposits (포화된 모래지반의 액상화후 과잉간극수압 소산양상)

  • 하익수;박영호;김명모
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2003.09a
    • /
    • pp.90-97
    • /
    • 2003
  • The purpose of this study is to understand the dissipation pattern of excess pore pressure after liquefaction which governs the post-liquefaction behavior of liquefied sand deposits. 1-g shaking table tests were carried out on 5 different kinds of sands, all of which had high liquefaction potentials. During the tests excess pore pressure at various depths, and surface settlements were measured. The measured curve of the excess pore pressure dissipation was simulated using the solidification theory, and from the analysis of the velocity of dissipation, the dissipation pattern of excess pore pressure after liquefaction was examined. The dissipation velocity of excess pore pressure after liquefaction had a linear correlation with the effective grain size ( $D_{10}$) divided by the coefficient of uniformity ( $C_{u}$), and the increase in the initial relative density of the ground played a role in shifting this correlation curve toward an increased dissipation velocity. From the correlation, an approximate method was recommended for prediction of the dissipation curve of excess pore pressure after liquefaction in saturated sand deposits.s.s.

  • PDF

Crytallization Behavior of Amorphous ${Si_{1-x}}{Ge_x)$ Films Deposited on $SiO_2$ by Molecular Beam Epitaxy(MBE) ($SiO_2$위에 MBE(Moleculat Beam Epitaxy)로 증착한 비정질 ${Si_{1-x}}{Ge_x)$박막의 결정화거동)

  • Hwang, Jang-Won;Hwang, Jang-Won;Kim, Jin-Won;Kim, Gi-Beom;Lee, Seung-Chang;Kim, Chang-Su
    • Korean Journal of Materials Research
    • /
    • v.4 no.8
    • /
    • pp.895-905
    • /
    • 1994
  • The solid phase crystallization behavior of undoped amorphous $Si_{1-x}Ge_{x}$ (X=O to 0.53) alloyfilms was studied by X-ray diffractometry(XRD) and transmission electron microscopy(TEM). Thefilms were deposited on thermally oxidized 5" (100) Si wafer by MBE(Mo1ecular Beam Epitaxy) at 300'C and annealed in the temperature range of $500^{\circ}C$ ~ $625^{\circ}C$. From XRD results, it was found that the thermal budget for full crystallization of the film is significantly reduced as the Ge concentration in thefilm is increased. In addition, the results also shows that pure amorphous Si film crystallizes with astrong (111) texture while the $Si_{1-x}Ge_{x}$ alloy film crystallzes with a (311) texture suggesting that the solidphase crystallization mechanism is changed by the incorporation of Ge. TEM analysis of the crystallized filmshow that the grain morphology of the pure Si is an elliptical and/or a dendrite shape with high density ofcrystalline defects in the grains while that of the $Si_{0.47}Ge_{0.53}$ alloy is more or less equiaxed shape with muchlower density of defects. From these results, we conclude that the crystallization mechanism changes fromtwin-assisted growth mode to random growth mode as the Ge cocentration is increased.ocentration is increased.

  • PDF

Determination of Critical State Parameters in Sandy Soils from Standard Triaxial Testing (I) : Review and Application (표준삼축시험으로부터 사질토에서의 한계상태정수 결정에 관한 연구 (I) : 고찰 및 적용)

  • 조계춘
    • Journal of the Korean Geotechnical Society
    • /
    • v.19 no.1
    • /
    • pp.61-75
    • /
    • 2003
  • Comprehensive review on the determination of critical state parameters in sandy soils from standard triaxial testing was performed to facilitate the application of critical state soil mechanics to the shear behavior of sandy soils. First, semantic differences in literature were clarified, inferring that critical state should be considered as the ultimate state at large deformation. Second, the characteristics of critical state parameters were discussed, and also the uniqueness of critical state line and the sensitivity of quasi-steady state condition were verified in relation to initial state, fabric, loading condition, and drainage condition. Third, as an example, the critical state soil mechanics was applied to evaluate the post-liquefaction shear strength, i.e. the reliable ultimate shear strength in liquified soils, in terms of critical state parameters.

Synthesis and Photopolymerization Kinetics of Polyether Urethane Methacrylate Oligomers (폴리에테르 우레탄 메타아크릴레이트 올리고머의 합성 및 광중합 동역학)

  • Oh, Sungae;Park, Kwangbae;Park, Chanik;Bae, Won
    • Clean Technology
    • /
    • v.12 no.1
    • /
    • pp.19-25
    • /
    • 2006
  • In this study, photo-cuarable urethane methacrylate oligomers were synthesized from polyether type polyol (PP series, GP series), isocyanate (2,4-toluene diisocyanate) and hydroxy acrylate (hydroxypropyl methacrylate). We measured basic property including color, viscosity and refractive index of resulting urethane methacrylate. Also we measured tensile strength, elongation, and Young's modulus after photo curing. Photo curing speed was investigated using photo-DSC (TA instrument). In the case of similar polyol structure, as the molecular weight of polyol is increased, tensile strength, Young's modulus, curing rate were decreased, but elongation was increased. As the number of functionality of urethane methacrylate oligomer is increased, tensile strength, Young's modulus, curing rate were increased, but elongation was decreased.

  • PDF