• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.506-508
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• 2007

We studied the nematic liquid crystal (NLC) alignment capability with a new alignment method utilizing an inkjet printed polyimide (PI) layer. A good, uniform LC alignment was achieved by the good PI printing using a new alignment method. The pretilt angle generated on the printed PI layer using the alignment method was almost the same as that on printed PI layer using rubbing alignment method. In addition, the good electro-optical performances of the new aligned twisted nematic (TN) cell with printed PI surface was obtained

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.1
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• pp.65-69
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• 2003

ZnO-Si-ZnO multi-layer thin films have been deposited by pulsed laser deposition (PLD). And then, the films have been annealed at 300$^{\circ}C$ in oxygen ambient pressure. Peak positions of ultraviolet (UV) and visible region were changed by addition of Si layer. Mobility of the films was improved slightly than ZnO thin film without Si layer. The structural property changed by inserting intermediate Si layer in ZnO thin film. The optical properties and structural properties of ZnO-Si-ZnO multi-layer thin films were characterized by PL(Photoluminescence) and XRB(X-ray diffraction) method, respectively. Electrical properties were measured by van der Pauw Hall measurements

• Computers and Concrete
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• v.20 no.3
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• pp.361-368
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• 2017

Seismic response of the concrete column covered by nanofiber reinforced polymer (NFRP) layer is investigated. The concrete column is studied in this paper. The column is modeled using sinusoidal shear deformation beam theory (SSDT). Mori-Tanaka model is used for obtaining the effective material properties of the NFRP layer considering agglomeration effects. Using the nonlinear strain-displacement relations, stress-strain relations and Hamilton's principle, the motion equations are derived. Harmonic differential quadrature method (HDQM) along with Newmark method is utilized to obtain the dynamic response of the structure. The effects of different parameters such as NFRP layer, geometrical parameters of column, volume fraction and agglomeration of nanofibers and boundary conditions on the dynamic response of the structure are shown. The results indicated that applied NFRP layer decreases the maximum dynamic displacement of the structure. In addition, using nanofibersas reinforcement leads a reduction in the maximum dynamic displacement of the structure.

• Smart Structures and Systems
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• v.16 no.5
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• pp.891-918
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• 2015

In many of microdevices a part of a microbeam is covered by a piezoelectric layer. Depend on the application a DC or AC voltage is applied between upper and lower side of the piezoelectric layer. A common method in many of previous works for evaluating the response of these structures is discretizing by Galerkin method. In these works often single mode shape of a uniform microbeam i.e. the microbeam without piezoelectric layer has been used as comparison function, and so the convergence of the solution has not been verified. In this paper the Galerkin method is used for discretization, and a comprehensive analysis on the convergence of solution of equation that is discretized using this comparison function is studied for both clamped-clamped and clamped-free microbeams. The static and dynamic solution resulted from Galerkin method is compared to the modal expansion solution. In addition the static solution is compared to an exact solution. It is denoted that the required numbers of uniform microbeam mode shapes for convergence of static solution due to DC voltage depends on the position and thickness of deposited piezoelectric layer. It is shown that when the clamped-clamped microbeam is coated symmetrically by piezoelectric layer, then the convergence for static solution may be obtained using only first mode. This result is valid for clamped-free case when it is covered by piezoelectric layer from left clamped side to the right. It is shown that when voltage is AC then the number of required uniform microbeam shape mode for convergence is much more than the number of required mode in modal expansion due to the dynamic effect of piezoelectric layer. This difference increases by increasing the piezoelectric thickness, the closeness of the excitation frequency to natural frequency and decreasing the damping coefficient. This condition is often indefeasible in microresonator system. It is concluded that discreitizing the equation of motion using one mode shape of uniform microbeam as comparison function in many of previous works causes considerable errors.

• Journal of Veterinary Science
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• v.21 no.3
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• pp.41.1-41.12
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• 2020

Background: The poultry red mite, Dermanyssus gallinae, is a serious problem in the laying hen industry worldwide. Currently, the foremost control method for D. gallinae is the implementation of integrated pest management, the effective application of which necessitates a precise monitoring method. Objectives: The aim of the study was to propose an accurate monitoring method with a reliable protocol for caged-layer poultry farms, and to suggest an objective classification for assessing D. gallinae infestation on caged-layer poultry farms according to the number of mites collected using the developed monitoring method. Methods: We compared the numbers of mites collected from corrugated cardboard traps, regarding with length of sampling periods, sampling sites on cage, and sampling positions in farm buildings. The study also compared the mean numbers of mites collected by the developed method with the infestation levels using by the conventional monitoring methods in 37 caged-layer farm buildings. Results: The statistical validation provided the suitable monitoring method that the traps were installed for 2 days on feed boxes at 27 sampling points which included three vertical levels across nine equally divided zones of farms. Using this monitoring method, the D. gallinae infestation level can be assessed objectively on caged-layer poultry farms. Moreover, the method is more sensitive than the conventional method in detecting very small populations of mites. Conclusions: This method can be used to identify the initial stages of D. gallinae infestation in the caged-layer poultry farms, and therefore, will contribute to establishment of effective control strategies for this mite.

• Korean Journal of Materials Research
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• v.16 no.2
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• pp.85-91
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• 2006

The fraction of $\varepsilon\;and\;\gamma$'-iron nitride in compound layer is predicted by x-ray diffraction using direct comparison method. The validity of formulation models was checked by comparing calculated results with metallographic analysis of iron nitride compound layer grown on steel S45C by gas nitriding. The fraction of $\varepsilon$ calculated by the three phase model, porous-$Fe_3N$/ dense-$Fe_3N$/ mixed layer with $Fe_3N\;and\;Fe_4N$, is 80 percent of that analyzed by etching technique. The $\varepsilon$ fraction predicted by mixed layer model is 122 percent of that measured by microscope.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.7
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• pp.261-266
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• 2001

The flexural vibration of laminated composite beams with active and passive constrained layer damping has been investigated to design a structure with maximum possible damping capacity. The equations of motion are derived fro flexural vibrations of symmetrical,. multi-layer laminated beams. The damping ratio and model damping of the first bending mode are calculated by means of iterative complex eigensolution method. The direct negative velocity feedback control is used for the active constrained layer damping. It is shown that the flexible laminated beam is more effective in the vibration control for both active and passive constrained layer damping. and this paper addresses a design strategy of laminated composite under flexural vibrations with constrained layer damping.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.392-398
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• 2000

When soft ground improvement is proceeded in costal area using compulsory replacement method, it is very important that the method of stability of embankment above replacement layer can be obtained if non-replaced soft layer is remained, and there are a lot of influence factors which affect the stability of embankment, such as replacement depth, the water content of dredged soil and the width of replacement layer, etc. If soft layer was replaced completely by good quality materials, there would be no problems about stability of embankment, but practically non-replaced layer would be remained as the strength of soft layer will be increased. So another consideration is required to get the stability of embankment. In this study, stability of embankment among these factors was compared, and from that results, the better way that could obtain the stability was presented.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.10
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• pp.855-860
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• 2001

Bi$_2$Sr$_2$CuO$_{x}$(Bi-2201) thin film were fabricated by atomic layer-by -layer deposition using an ion beam sputtering method. 10 wt% and 90 wt% ozone mixed oxygen were used with ultraviolet light irradiation to assist oxidation. XRD and RHEED investigations revealed that a buffer layer is formed at the early stage of deposition (less than 10 unit cell), and then c-axis oriented Bi-2201 grows on top of it.t.

• Journal of Advanced Navigation Technology
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• v.13 no.3
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• pp.351-357
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• 2009

In this paper, we studied an efficient inter-working method in which QualNet network simulator can import WAVE channel model and physical layer simulation module pre-designed by Matlab tool. At first, we investigated physical layer and communication medium simply designed in QualNet, then we suggested practical method for QualNet network simulator to adopt different type of physical layer simulation module in which detailed multi-path fading channel model and IEEE802.11p communication modem are designed. This work should be applied to linked simulation between upper layer and lower physical layer for total simulation from higher layer to lower physical layer related to next generation DSRC/WAVE specification.