• Korean Journal of Poultry Science
• /
• v.22 no.2
• /
• pp.85-95
• /
• 1995

This study was conducted to investigate the immune response of layers fed diets supplemented with excess micronutrients, i.e., vitamin A, methionine, Zn, Cu, and Fe to the inoculation of Newcastle disease vaccine(NDV) or infectious bronchitis vaccine(IBV). The antibody titer against the NDV increased immediately after the inoculation and stayed high during the next 6 wk. On the other hand, The antibody titer against the IBV increased after 4 wk of inoculation The IgM level increased rapidly after 1 wk of NDV inoculation, however, it decreased after 5 wk of inoculation. The IgA displayed similar pattern to that of IgM in response to NDV inoculation. The pattern of IgM change after IBV inoculation was similar to that when layers were treated with NDV. However, IgA level changed earlier than did IgM. The IgG response to the NDV and IBV was very weak compared to the other immune responses. The excess supplementation of micronutrients to the diets of layers inoculated with NDV elicited favorable antibody titer and immune response compared to the layers fed the control diet. The excess Zn, however, allowed the layers to have higher antibody titer for the 4-wk period after NDV injection: after that they showed no effect of extra-Zn. The immune responses of layers fed excess vitamin A, Cu, methionine, and Fe were markedly higher in IgA and IgG than the control layers. The excess Zn, however, did not bring about any favorable result. No difference was detected in IgG level between control and micronutrients-treated groups.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.47 no.6
• /
• pp.47-57
• /
• 2005

Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research presents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer fur its vertical and horizontal stresses in (1) homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stresses fumed out to be different in the value of theoretical and actual measurement after the trial examination of model. This study has the purpose of suggesting the better construction method of running equipment on weak stratum by comparing the estimated value of trial experiment and theory on underground stress of the weak ground surface area and of raising up the necessity of the continuous research hereafter.

• Journal of Magnetics
• /
• v.9 no.2
• /
• pp.40-46
• /
• 2004

The magnetic properties of sputtered ($Ni_{83}Fe_{17}/Au/Co/Au$) multilayers with various thicknesses of Au (0.5 {\leq} t_{Au} {\leq} 3 nm), Ni-Fe ($1{\leq}t_{Ni-Fe}{\leq}4nm$) and Co ($0.2{\leq}t_{co}{\leq}1.5nm$) layers were characterized. An alternating in-plane and out-of-plane anisotropy of the ferromagnetic layers was achieved for the structures ($t_{Au}{\geq}1.5nm$) showing a weak coupling between the Ni-Fe layers with an in-plane anisotropy and the Co layers ($0.3{\leq}t_Co{\leq}1.2nm$) with a perpendicular anisotropy. For such a structure, a detailed discussion on the GMR effect is presented, relating to the magnetization reversal from a mutually perpendicular magnetic configuration at the remanence to a parallel one at the saturation. An influence of the dense labyrinth domain structure on the magnetoresistance effect is also addressed.

• International Journal of Fluid Machinery and Systems
• /
• v.5 no.2
• /
• pp.49-59
• /
• 2012

The present study is devoted to the influence of a superposed radial inflow in a rotor-stator cavity with a peripheral opening. The flow regime is turbulent, the two boundary layers being separated by a core region. An original theoretical solution is obtained for the core region, explaining the reason why a weak radial inflow has no major influence near the periphery of the cavity but strongly affects the flow behavior near the axis. The validity of the theory is tested with the help of a new set of experimental data including the radial and tangential mean velocity components, as well as three components of the Reynolds stress tensor measured by hot-wire anemometry. The theoretical results are also in good agreement with numerical results obtained with the Fluent code and experimental data from the literature.

• Steel and Composite Structures
• /
• v.24 no.5
• /
• pp.523-536
• /
• 2017

A layerwise (LW) formulation based on the Galerkin method is presented to investigate the three-dimensional stress state in long sandwich plate which is subjected to tension force and pure bending moment. Based on the Galerkin method and the LW discretization approach, the equilibrium equations of elasticity for the long plate are written in the weak form and discretized through the thickness of the plate. The discretized equations are written in terms of displacement components of the numerical layers. The governing equations of the plate are solved analytically for the free edge boundary conditions. The distribution of stress state especially the 3D stress state in the vicinity of the edges of the sandwich plate which is subjected to tension and pure bending is studied. In order to increase the accuracy, the out of plane stresses are obtained by integrating the equilibrium equations of elasticity. The convergence and accuracy of the predictions are studied and various numerical results are presented for distribution of the in-plane and out of plane stresses in symmetric and un-symmetric sandwich plates.

• Proceedings of the Korean Society of Agricultural Engineers Conference
• /
• 2005.10a
• /
• pp.423-428
• /
• 2005

If the load of constructing vehicles during the construction work acts on the road or the ground surface on the soft ground, due to the excess stresses in soils the trafficability of the vehicles influences the constructing efficiency, constructing period and so on. Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research represents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer for its vertical and horizontal stress in (1)homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stress turn out to be different in the value of theoretical and actual measurement after the trial examination of model.

• Journal of the Korean institute of surface engineering
• /
• v.34 no.6
• /
• pp.537-544
• /
• 2001

In the present study, tin-zinc alloys were coated on a cold-rolled steel sheet with variations of electrolyte concentration, additives quantity and current density employing the Hull cell and circulation cell simulator. With an addition of additives of 2m1/L, tin-zinc deposits containing 10 to 40 percent Zn revealed a good surface appearance with weak acidic electrolytes. The organic additives suppressed the Sn deposition rate and thus increased the zinc contents in tin-zinc coating layers. The zinc contents in the tin-zinc coating layers depended almost linearly on the concentrations of metal ions of tin and zinc. Temperature of the electrolyte affected the composition tin-zinc coating layer. However, the concentration of complexants revealed little effectiveness. The surface morphology of tin-zinc coating showed dense tin and zinc phases with fine equiaxed grains with the high current density.

• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.11
• /
• pp.1288-1296
• /
• 2011

Effective elastic constants of bone-like biocomposites are investigated numerically. The bone-like materials are composed of strong layers and weak layers, and hierarchically structured. The unit cell model is employed to obtain the effective elastic constants. The effective anisotropic elastic constants of bone-like composites are obtained by using the potential energy method and finite element analysis. The effects of the Poisson's ratio, elastic modulus, hierarchical level, volume fraction and aspect ratio of the strong layer composed of the composites on the effective elastic constants are discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.22 no.4
• /
• pp.323-326
• /
• 2009

We have developed blue-emitting phosphorescent organic light emitting diodes (OLEDs) using 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and tris (8-quinolinolato)aluminum ($Alq_3$) electron transport layers. As blue dopant and host materials, bis[(4,6-di-fluorophenyl)-pyridinate-N,C2']picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP) were used, respectively. The driving voltage, current efficiency and emission characteristics of devices were investigated. While the driving voltage was about $1{\sim}2$ V lower in the device with an $Alq_3$ layer, the current efficiency was about 66 % higher in the device with BCP electron transport layer. the blue phosphorescent OLED with BCP layer exhibited higher purity of color, resulting from a relatively weak electroluminescence intensity at 500 nm.

• Journal of Magnetics
• /
• v.20 no.3
• /
• pp.201-206
• /
• 2015

Using the Vienna ab initio simulation package (VASP) incorporating both semiempirical and nonlocal van der Waals interaction, the structural, adsorption, and magnetic properties of Ni/BN/Co systems were investigated. We proposed that the relative spin direction of Ni and Co magnets can be easily tuned, because the total energy difference between ferromagnetic (FM) and antiferromagnetic (AFM) states is small. Despite this feature, very interestingly, both Ni and Co layers manifest half-metallic state, whereas the spacer BN layer becomes weak metal for one monolayer (ML) thickness and an insulating barrier for two ML thicknesses. The half-metallic behavior of the magnetic layers seems very robust, because it is independent of the magnetic coupling between Ni and Co. This finding indicates that the Ni/BN/Co system can be used as a potential candidate for tunneling magnetoresistance system.