• 제목/요약/키워드: L-shape

검색결과 1,856건 처리시간 0.03초

평면 Rolling에 의한 표면특성 변화에 관한 연구(l) (A Study on the Change of Suface Characteristics by plane suface Rolling(l))

  • 김희남
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1997년도 춘계학술대회 논문집
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    • pp.1-5
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    • 1997
  • The plane surface rolling, one of the plastic working process, good surface condition due to increase of surface roughness and hardness. It is well known that mechanism of surface rolling depends upon rolling conditions such as rolling speed, contact pressure, step length of rolling, the shape of roller and mechanical properties of material. In this study, the optimal value of the above parameter on the surface roughness were investigated by using the rolling tool with NACHI 6000ZZ ball bearing outer races on machine structure carbon steel[SM45C]

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QFP 패키지의 새로운 고주파 등가 회로 모델 (New High-Frequency Equivalent Circuit Model for QFP Package)

  • 김성종;송상헌
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제54권7호
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    • pp.339-342
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    • 2005
  • We present a new high-frequency equivalent circuit model for 52pin QFP used in typical IC's and extract R, L, and C values of this circuit model using a 3-D E & M field simulator. Futhermore, L and C value variations as a function of Pin number due to the shape differences of the leads have been fitted to 2nd order polynomials in order to extend the applicability of this model.

T.L.SHELL의 응력해설 (The Analysis of T. L. Shell)

  • 임영배;이수곤
    • 건축사
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    • 제4권14호통권14호
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    • pp.74-79
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    • 1969
  • As we all know a large number of thin shell with the shape of E.P and H.P have been constructed. In this paper, we will be interested to the bending problem of thin translational shell. Two basic differential equations of shallow shell are to be used to derive approximate solution of it. Stress analysis of E.P. translational shell with constant thickness under uniform surface oad is to be given as an example. More exact solution formulated by K. Apeland can be found in the proceeding, Journal of the Engineering Mechanics Division, A.S.C.E., Feburary, 1961.

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Limit analysis of rectangular cavity subjected to seepage forces based on Hoek-Brown failure criterion

  • Yang, X.L.;Qin, C.B.
    • Geomechanics and Engineering
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    • 제6권5호
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    • pp.503-515
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    • 2014
  • On the basis of Hoek-Brown failure criterion, a numerical solution for the shape of collapsing block in the rectangular cavity subjected to seepage forces is obtained by upper bound theorem of limit analysis. The seepage forces obtained from the gradient of excess pore pressure distribution are taken as external loadings in the limit analysis, and the pore pressure is easily calculated with pore pressure coefficient. Thus the seepage force is incorporated into the upper bound analysis as a work rate of external force. The upper solution of the shape of collapsing block is derived by virtue of variational calculation. In order to verify the validity of the method proposed in the paper, the result when the pore pressure coefficient equals zero, and only hydrostatic pressure is taken into consideration, is compared with that of previous work. The results show good effectiveness in calculating the collapsing block shape subjected to seepage forces. The influence of parameters on the failure mechanisms is investigated.

포장지의 발수도 자동 해석 시스템 개발 -KS M 7057에 근거한 발수도 자동 측정- (Development of Automatic Analysis System for Water Repellency of Packaging Paper -Automatic Measurement of Water Repellency Based on KS M 7057-)

  • 김철환;최경민;강진기;박종열
    • 펄프종이기술
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    • 제35권1호
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    • pp.7-12
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    • 2003
  • The test results for water repellency of paper and paperboard according to KS M 7057 can readily be influenced by an operator's bias. In order to discard such bias, the automatic analysis program of water repellency was developed based on different shape features of a liquid trace formed on a specimen. That is, the shape of a liquid track flowing down on the specimen with an angle of $45^{\circ}$ was evaluated according to width variation between head and tail of the trace($S_{Hr}$), uniformity of a liquid flow($S_{d}$), length of long traces($L_{SHr}$), eccentricity of liquid traces($E_{i}$), and then was recognized as a specific degree of water repellency. Finally, the automatic analysis system of water repellency based upon KS M 7057 made it possible to readily measure water resistance of paper and paperboards classified into R0 to R10.

직교배열표와 유한요소해석을 이용한 너클의 형상최적설계 (Shape Optimization Design of the Knuckle using the Orthogonal Array and the Finite Element Analysis)

  • 박영철;이권희;이동화;이강영
    • 한국자동차공학회논문집
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    • 제11권3호
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    • pp.138-144
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    • 2003
  • Recently, the weight reduction of vehicle influences its environment problems and performances. It is a trend that a lot of parts have been currently changed to an aluminum alloy from steel materials. In this study, the shape optimization using an orthogonal array is performed to determine the design of the knuckle which is a part of suspension system. With the material of the weight reduction was achieved by satisfying the constraints of a strength requirement. The orthogonal array of $L_{18}$ is introduced to find the optimum design variables that considers the shape of the knuckle. The characteristic function composed of the objective and the construct is defined to the feasibility. Comparing to the weight of the initial design with steel materials that of optimum design with aluminum alloy material is reduced by 60%.

Orient종 잎담배의 이면교잡에 의한 양적 형질의 유전연구 II. 분산분석과 유전자분포 상태 (The Analysis of Inheritance of Quantitative characters with Oriental Tobacco Varieties (Nicotiana tabacum L.) in Diallel Cross. II. Gene Distribution and Analysis of Variance for each character in $F_1$ Generation.)

  • 정석훈;황주광;손세호
    • 한국연초학회지
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    • 제4권1호
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    • pp.15-20
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    • 1982
  • This experiment was carried out to investigate the degrees and directions of dominance, and gene distributions by analysing diallel crosses of oriental varieties. The analysis of Wr-Vr indicated non-allelic gene interaction for days to (lowering and number of leaves. Five Plant characteristics showed different degrees of dominance : incomplete dominance for Plant height and leaf shape, over dominance for , wield and sugar, and complete dominance for nicotine. It was shown that additive genetic variance was predominant for plant height, leaf shape, and total sugar. More number of dominant genes were present in Kavala and canthi for Plant height; Basma, Samsun and Izmir for leaf shape ; and Basma and Samsun (or nicotine. Their directions of dominance were tall height, narrow leaves, and low nicotine, respectively.

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인체의 성상신경절의 크기와 위치 (The Size and Location of Human Stellate Ganglion)

  • 강준구
    • The Korean Journal of Pain
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    • 제7권2호
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    • pp.170-174
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    • 1994
  • Stellate Ganglion (SG) of l0 cadavers were removed during autopsy at Saga Medical College. Length, width, thickness, shape and location of SG were measured before formalin fixation. The results are as follows; 1) Length, width, thickness of SG were 22.33+5.23mm, 9.34+2.23mm and 5.03+1.19mm in right respectively, and 29.67+10.56 mm, 11.29+3.20mm and 5.51+1.09mm respectively in left. 2) Weight of right SG is 0.69+0.25 gm and weight of left SG is 1.04+0.63 gm. 3) Shape of SG is oval and snowman type. 4) Location of SG is variably located from the base of 7th cervical vertebra to first thoracic vertebra.

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