• KSBB Journal
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• v.5 no.4
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• pp.391-396
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• 1990

4.0$\times$10-3 (IU/cells/day) of maximum specific scu-PA production, which was higher than those by a 75$\textrm{cm}^2$ T-flask and conventional perfusion systems, was maintained by tube-type bioreactor at 0.35 (1/h) of perfusion rate corresponding to 0.15 (dynes/$\textrm{cm}^2$) of shear stress. The production of scu-PA is also increased as shear stress was slowly increased, which is similar to natural human blood circulation. The tube reactor proves that there may be no limitation of oxygen supply by showing 1.0 (1/h) of oxygen transfer coefficient at steady state and this system yields much lower shear stress of 0.3(dynes/$\textrm{cm}^2$) than that of 5-8(dynes/$\textrm{cm}^2$) by conventional agitation systems.

• Journal of the Korean Graphic Arts Communication Society
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• v.21 no.1
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• pp.1-10
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• 2003

Printing ink is faced various shear stress situation until it transfer to the printed substrate through the press. And in each shear stress condition the ink is needed to keep the appropriate viscosity according to the condition. The change of printing ink viscosity has been explained by well-known through the viscosity profile curve. But actually, the quality of printed paper depends on the ink behavior after transfer the substrates. Like this, to look into the behaviour of the ink on the printed substrate, it is needed the experiment of the ink structure recovering by rheology study. In this study, by controling the $CaCO_3$ content in the ink, after investigating the effect of the ink's structure recovery of the pigment concentration, we intend to predict the printing quality of the ink behvior on the substrate depending on pigment content.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.12
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• pp.945-953
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• 2008

Laminar film condensation of saturated vapor in forced flow over a flat plate is analysed. The problem is formulated as exact boundary-layer solution and integral approximate solution. From numerical solutions of the governing equations, it is found that the energy transfer by convection and the effect of inertia term in the momentum equation in negligibly small for low pressure but quite important for high pressure. The condensate rate, liquid-vapor interfacial shear stress and local heat transfer are strongly dependent on the reduced pressure $P_r$ and the modified Jacob number Ja/Pr.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.21 no.4
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• pp.245-275
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• 2017

The present investigation deals, Dufour and heat source effects on radiative MHD slip flow of a viscous fluid in a parallel porous plate channel in presence of chemical reaction. The non-linear coupled partial differential equations are solved by using two term perturbation technique subject to physically appropriate boundary conditions. The numerical values of the fluid velocity, temperature and concentration are displayed graphically whereas those of shear stress, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. By increasing the slip parameter at the cold wall the velocity increases whereas the effect is totally reversed in the case of shear stress at the cold wall. It is observed that the effect of Dufour and heat source parameters decreases the velocity and temperature profiles.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.169-172
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• 2005

Numerical analysis of turbulent flow in three-dimensional channel with V-shaped ribs extruded on both walls has been carried out. Reynolds-averaged Navier-Stokes are calculated for analysis of fluid flow and heat transfer. Shear stress transport (SST) turbulence model is used as a turbulence closure. Computational results for heat transfer rate show good agreements with experimental data.

• Structural Engineering and Mechanics
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• v.73 no.2
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• pp.109-121
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• 2020

This study aims to estimate crack location and crack length in damaged beam structures using transfer matrix formulations, which are based on analytical solutions of governing equations of motion. A single variable shear deformation theory (SVSDT) that considers parabolic shear stress distribution along beam cross-section is used, as well as, Timoshenko beam theory (TBT). The cracks are modelled using massless rotational springs that divide beams into segments. In the forward problem, natural frequencies of intact and cracked beam models are calculated for different crack length and location combinations. In the inverse approach, which is the main concern of this paper, the natural frequency values obtained from experimental studies, finite element simulations and analytical solutions are used for crack identification via plots of rotational spring flexibilities against crack location. The estimated crack length and crack location values are tabulated with actual data. Three different beam models that have free-free, fixed-free and simple-simple boundary conditions are considered in the numerical analyses.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.2
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• pp.101-111
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• 2021

Two different types of shear-friction tests were classified by external loadings and referred to as a push-off and a pull-off test. In a pull-off test, a tension force is applied in the transverse direction of the test specimen to produce a shear stress at the shear plane. This paper presents a method to evaluate shear transfer strengths of uncracked pull-off specimens. The method is based on the compression field theory and different constitutive laws are applied in some ways to gain accurate shear strengths considering softening effects of concrete struts based on Modified Compression Field Theory (MCFT) and Softened Truss Model (STM). The validity of the proposed method is examined by applying to some selected test specimens in literatures and results are compared with the predicted values. A general agreement is observed between predicted and measured values at ultimate loading stages in initially uncracked pull-off test specimens. A shear strength evaluation formula considering the effective compressive strength of a concrete strut was proposed, and the applicability of the proposed formula was verified by comparing with the experimental results in the literature.

• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.429-436
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• 2000

The composite system, which is consisted of the steel girder and reinforced concrete column has some advantages in the structural efficiency and the construction productivity by complementing the shortcomings between the two materials. This research is aimed at the development of the composite beam-column connection system by which the steel beam can be connected to the R/C column with smooth stress transfer. And, to ensure safety of this system, the tests of moment and shear resisting performance have been carried out for actual size specimen. From the test, the connection system has been preyed to take good resistance and stress transfer between steel girder and reinforced concrete column.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.513-520
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• 2005

The uniform truss mechanism is widely accepted as a shear transfer mechanism in reinforced concrete members. However, the uniform truss action cannot be expected when the bond stress distribution is not constant along longitudinal bars. A test method in which only the truss action takes place is developed and conducted to investigate the truss actions under various bond contributions. Based on the experimental results and analysis, the following findings can be obtained: 1) The bond stress distribution depends on the axial compression force, the amount of shear reinforcement and loading conditions. 2) The analysis using the combined truss model consisting of uniform and fan-shape trusses can predict the experimental results

• Journal of the Korean GEO-environmental Society
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• v.10 no.5
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• pp.59-67
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• 2009

Three-dimensional (3D) numerical analyses have been conducted to study the behaviour of a single pile to tunnelling. The numerical analysis has included soil slip at the pile-soil interface. In the numerical analyses the interaction between the tunnel and the pile constructed in weathered soil and rock has been analysed. The study includes the pile settlement, the relative shear displacement between the pile and the soil and the shear stresses at the interface and the axial force on the pile. In particular, the shear stress transfer mechanism at the pile-soil interface related to the tunnel advancement has been rigorously analysed. Due to changes in the relative shear displacement at the pile-soil interface during the tunnel advancement, the shear stress and the axial force distributions along the pile have been changed. Upward shear stress developed at most part of the pile (Z/L=0.0-0.8), while downward shear stress is mobilised near the pile tip (Z/L=0.8-1.0) resulting in tensile force on the pile, where Z is the pile location and L is the pile length. Some insights into the pile behaviour to tunnelling obtained from the numerical analyses will be reported and discussed.