• Title/Summary/Keyword: Strip method

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Tension/Heat/Thermal Deformation Analysis of a Cold Coiled Strip in Coiling Process (냉연 판재의 권취공정에 있어서 장력/열/변형 해석)

  • 정영진;이규택;강충길
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2002.05a
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    • pp.39-43
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    • 2002
  • A new model for heat transfer and thermal deformation analysis according to strip mm in coiling process has been proposed. Finite difference analyses for heat transfer of cold rolled coil have been carried out under various coiling tensions and strip crown using the equivalent thermal conductivity for the radial direction of cold rolled coil which is a function of strip thickness, surface characteristics and compressive pressure. The compressive pressure is calculated from a equation expressed as a function of hoop stress and coil tension considering strip mm obtained by experiment. Finite element method for thermal deformation of cold rolled coil has been performed to investigate the effects of the strip crown, the coil tension and temperature. From these analyses, it is found that the axial inhomogeneity of thermal deformation is increased as the strip crown, compressive pressure, and temperature drop in cold coiled strip increase.

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TENSION CONTROL SYSTEM FOR HOT STRIP MILLS (열간 압연 공정에서의 장력 제어시스템)

  • Park, Sung-Han;Ahn, Byoung-Joon;Lee, Man-Hyung
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2267-2269
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    • 2001
  • The looper control of hot strip finishing mill is one of the most important control item in hot strip rolling mill process. Loopers are placed between finishing mill stands and control the mass flow of the two stands. Another important action of the looper is to control the strip tension which influences on the width of the strip. So it is very important to control both the looper angle and the strip tension simultaneously but the looper angle and the strip tension are strongly interacted by each other. There are many control schemes such as conventional, non-interactive, LQ, LQG/LTR, and ILQ control in the looper control system. In this paper, we present the modeling for the looper of a hot strip finishing mill to control the tension of the strip and suggest the non-interactive(cross) and LQG/LTR control method.

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The roll gap control hydraulic hot strip mill using time delay control method (TDC기법을 이용한 유압식 열연압연기의 롤갭제어)

  • 홍성철;현장환;이정오
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1469-1472
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    • 1996
  • Hydraulic Hot Strip Mill (HHSM) rolls materials whose size and stiffness are various. So a roll gap controller for HHSM was designed using TDC(Time Delay Control) method. The performance of the roll gap control was evaluated through computer simulations. The simulation results indicate that TDC method show excellent robustness and tracking properties against PID control method in various rolling conditions.

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Image Analysis of a Lateral Flow Strip Sensor for the Detection of Escherichia coli O157:H7

  • Kim, Giyoung;Moon, Ji-Hea;Park, Saet Byeol;Jang, Youn-Jung;Lim, Jongguk;Mo, Changyeun
    • Journal of Biosystems Engineering
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    • v.38 no.4
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    • pp.335-340
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    • 2013
  • Purpose: This study was performed to develop a lateral flow strip sensor for the detection of pathogenic Escherichia coli O157:H7 in various samples. Also, feasibility of using an image analysis method to improve the interpretation of the strip sensor was evaluated. Methods: The lateral flow strip sensor has been fabricated based on nitrocellulose lateral-flow membrane. Colloidal gold and E. coli O157:H7 antibodies were used as a tag and a receptor, respectively. Manually spotted E. coli O157:H7 antibody and anti-mouse antibody on nitrocellulose membrane were used as test and control dots, respectively. Feasibility of the lateral flow strip sensor to detect E. coli O157:H7 were evaluated with serially diluted E. coli O157:H7 cells in PBS or food samples. Test results of the lateral flow strip sensor were measured with an image analysis method. Results: The intensity of the test dot started to increase with higher concentration of the cells were introduced. The sensitivities of the sensor were both $10^4$ CFU/mL Escherichia coli O157:H7 spiked in PBS and in chicken meat extract, respectively. Conclusions: The lateral flow strip sensor and image analysis method could detect E. coli O157:H7 in 20 min, which is significantly quicker than conventional plate counting method.

Development and Assessment of Conductive Fabric Sensor for Evaluating Knee Movement using Bio-impedance Measurement Method (슬관절 운동 평가를 위한 생체 임피던스 측정용 전도성 섬유센서 개발 및 평가)

  • Lee, Byung-Woo;Lee, Chung-Keun;Cho, Ha-Kyung;Lee, Myoung-Ho
    • Journal of Biomedical Engineering Research
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    • v.32 no.1
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    • pp.37-44
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    • 2011
  • This paper describes the development and assessment of conductive fabric sensor for evaluating knee movement using bio-impedance measurement method. The proposed strip-typed conductive fabric sensor is compared with a dot-typed Ag/AgCl electrode for evaluating validity under knee movement condition. Subjects are composed of ten males($26.6{\pm}2.591$) who have not had problems on their knee. The strip-typed conductive fabric sensor is analyzed by correlation and reliability between a dot-typed Ag/AgCl electrode and the strip-typed conductive fabric sensor. The difference of bio-impedance between a dot-typed Ag/AgCl electrode and the strip-typed conductive fabric sensor averages $7.067{\pm}13.987\;{\Omega}$ As the p-value is under 0.0001 in 99% of t-distribution, the strip-typed conductive fabric sensor is correlated with a dot-typed Ag/AgCl electrode by SPSS software. The strip-typed conductive fabric sensor has reliability when it is compared with a dot-typed Ag/AgCl electrode because most of bio-impedance values are in ${\pm}1.96$ standard deviation by Bland-Altman Analysis. As a result, the strip-typed conductive fabric sensor can be used for assessing knee movement through bio-impedance measurement method as a dot-typed Ag/AgCl electrode. Futhermore, the strip-typed conductive fabric sensor is available for wearable circumstances, applications and industries in the near future.

Assumed strain finite strip method using the non-periodic B-spline

  • Hong, Hyun-Seok;Kim, Kyeong-Ho;Choi, Chang-Koon
    • Structural Engineering and Mechanics
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    • v.18 no.5
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    • pp.671-690
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    • 2004
  • An assumed strain finite strip method(FSM) using the non-periodic B-spline for a shell is presented. In the present method, the shape function based on the non-periodic B-splines satisfies the Kronecker delta properties at the boundaries and allows to introduce interior supports in much the same way as in a conventional finite element formulation. In the formulation for a shell, the geometry of the shell is defined by non-periodic B3-splines without any tangential vectors at the ends and the penalty function method is used to incorporate the drilling degrees of freedom. In this study, new assumed strain fields using the non-periodic B-spline function are proposed to overcome the locking problems. The strip formulated in this way does not posses any spurious zero energy modes. The versatility and accuracy of the new approach are demonstrated through a series of numerical examples.

A Method of the Linear Approximation of Digital Curves By the Separate Rotation of Two Strip Lines (두 Strip 직전의 분리 회전을 이용한 디지털 곡선의 직선 근사화)

  • Sung Pil Lyu
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.4
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    • pp.115-122
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    • 1994
  • Roberige had proposed a method of linear approximation using strips. This method is known to be fast relatively, and the distance between the given curve and calculated straight line is not greater than an allowable error. But this method generates many break points. Later, Leng and Yang proposed the dynamic strip algorithm with the rotation of strips which reduced the number of greak points at the sacrifice of the speed. The method using the seperate rotation of two strip lines proposed in this paper is faster than Leng and Yang's but generates almost the same number of break points as Leng and Yang's.

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Influence of interaction between coal and rock on the stability of strip coal pillar

  • Gao, W.
    • Geomechanics and Engineering
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    • v.16 no.2
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    • pp.151-157
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    • 2018
  • The constrained conditions of roof and floor for the coal pillar affect the strength of coal pillar very seriously. To analyze the influence of rock mass for the roof and floor on the stability of coal pillar comprehensively, one method based on the mechanical method for the composite rock mass was proposed. In this method, the three rock layers of roof, floor and coal pillar are taken as the bedded composite rock mass. And the influence of rock mass for the roof and floor on the elastic core of coal pillar has been analyzed. This method can obtain not only the derived stress by the cohesive constraining forces for the coal pillar, but also the derived stress for the rock mass of the roof and floor. Moreover, the effect of different mechanical parameters for the roof and floor on the stability of coal pillar have been analyzed systematically. This method can not only analyze the stability of strip coal pillar, but also analyze the stability of other mining pillars whose stress distribution is similar with that of the strip coal pillar.

Vibration and stability analyses of thick anisotropic composite plates by finite strip method

  • Akhras, G.;Cheung, M.S.;Li, W.
    • Structural Engineering and Mechanics
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    • v.3 no.1
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    • pp.49-60
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    • 1995
  • In the present study, a finite strip method for the vibration and stability analyses of anisotropic laminated composite plates is developed according to the higher-order shear deformation theory. This theory accounts for the parabolic distribution of the transverse shear strains through the thickness of the plate and for zero transverse shear stresses on the plate surfaces. In comparison with the finite strip method based on the first-order shear deformation theory, the present method gives improved results for very thick plates while using approximately the same number of degrees of freedom. It also eliminates the need for shear correction factors in calculating the transverse shear stiffness. A number of numerical examples are presented to show the effect of aspect ratio, length-to-thickness ratio, number of plies, fibre orientation and stacking sequence on the natural frequencies and critical buckling loads of simply supported rectangular cross-ply and arbitrary angle-ply composite laminates.

Analysis of TE Scattering by a Resistive Strip Grating Over a Grounded Dielectric Layer Using Point Matching Method (Point Matching Method를 이용한 접지된 유전체층 위의 저항띠 격자구조에 의한 TE 산란 해석)

  • Yoon, Uei-Joong
    • Journal of Advanced Navigation Technology
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    • v.18 no.4
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    • pp.371-375
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    • 2014
  • In this paper, the solutions of TE(transverse electric) scattering problems by a resistive strip grating over a grounded dielectric layer are analyzed by applying the PMM(point matching method) known as a numerical method of electromagnetic fileld. The boundary conditions are applied to obtain the unknown field coefficients and the resistive boundary condition is used for the relationship between the tangential magnetic field and the induced surface current density on the resistive strip. The induced surface current density of resistive strip is obtained by difference of the up and down of the magnetic field in two boundary areas of the resistive strip. The numerical results for reflected power of zeroth order mode analyzed by according as the resistivity, the width and spacing of resistive strip, the relative permittivity and thickness of dielectric layer, and incident angles. The numerical results shown in good agreement compared to those of the existing papers using FGMM(fourier galerkin moment method).