• 한국자기학회지
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• 제15권6호
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• pp.303-306
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• 2005

Micromagnetics 전산 모사를 이용하여 국소적 층간교환상호작용이 있는 강자성/비자성/강자성 다층박막 구조에서 Bloch 자벽이나 Neel 자벽보다 더 얇은 두께의 자벽이 인위적으로 형성될 수 있음을 보였고, 이때 생성된 좁은 자벽의 두께가 강자성층의 두께에 의해 영향을 받음을 보였다. 국소적 층간교환상호작용을 가진 $Fe_1/Cr/Fe_2$ 구조에서 좁은 자벽이 생성됨을 보였고, $Fe_2$ 층의 두께를 20nm로 고정시키고 $Fe_1$층의 두께를 각각 1, 2, 4, 6nm으로 변화시켜가며 전산 모사를 수행하여 $Fe_1$ 층의 두께가 감소함에 따라 자벽의 두께가 얇아짐을 확인하였다.

• Structural Engineering and Mechanics
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• 제28권6호
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• pp.749-765
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• 2008

Free axisymmetric vibrations of layered cylindrical shells of variable thickness are studied using spline function approximation techniques. Three different types of thickness variations are considered namely linear, exponential and sinusoidal. The equations of axisymmetric motion of layered cylindrical shells, on the longitudinal and transverse displacement components are obtained using Love's first approximation theory. A system of coupled differential equations on displacement functions are obtained by assuming the displacements in a separable form. Then the displacements are approximated using Bickley-spline approximation. The vibrations of two-layered cylindrical shells, made up of several types of layered materials and different boundary conditions are considered. Parametric studies have been made on the variation of frequency parameter with respect to the relative layer thickness, length ratio and type of thickness variation parameter.

• 한국전기전자재료학회논문지
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• 제26권3호
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• pp.209-215
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• 2013

DSSCs electrical characteristics and efficiency fabricated with different tape casting thickness Pt counter electrodes and different thickness between $TiO_2$ photo electrode and Pt counter electrode substrate were studied. 1 layer Pt counter electrode shows 3.979% efficiency. Efficiency increased as tape casting thickness decreased. The lowest open-circuit voltage was a 0.726 V and the highest short-circuit current was a 2.188 mA on 1 layer Pt counter electrode. On the different thickness between two substrates, the lowest open-circuit voltage 0.712 V and the highest short-circuit current 2.787 mA was measured at $60{\mu}m$ surlyn film thickness and it shows the highest value of 5.067% efficiency.

• 한국운동역학회지
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• 제20권4호
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• pp.415-420
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• 2010

The purpose of this study was to compare the thickness of the abdominal muscles during single leg holding exercise (SLH) in a hooked lying position on stable surface and on a foam roller. Healthy twenty subjects who had no medical history of lower extremity or lower back pain were recruited for this study. Muscle thickness of transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) was recorded using real-time ultrasonography during SLH. Paired t-test with Bonferroni adjustment was used to compare the muscles thickness during SLH on stable surface and on a foam roller. The result showed that TrA and IO muscle demonstrated greater thickness during SLH on foam roller than those on the stable surface. This finding suggests that SLH on an unstable foam roller is more effective to increase thicknesses of TrA and IO muscles than stable surface.

• 한국진공학회지
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• 제8권3A호
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• pp.231-237
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• 1999

$SrBi_{22.4}Ta_2O_9$ (SBT) thin films of 70~150 nm thickness were prepared on platinized silicon substrates by Liquid Source Misted Chemical Deposition (LSMCD) process, and their microstructure, feroelectric and leakage current characteristics were investigated. By annealing at $800^{\circ}C$ for 1 hour in oxygen ambient, SBT films were fully crystallized to the Bi layered perovskite structure without preferred orientation. The grain size of the LSMCD- derived SBT films was about 100nm, and was not varied with the film thickness. $2P_r$ and $E_c$ of the SBT films increased with decreasing the film thickness, and the 70nm-thick SBT film exhibited $2P_r$ of 17.8 $\mu$C/$\textrm{cm}^2$ and $E_c$ of 74kV/cm at applied voltage of 5V. Within the film thickness range of 70~150nm, the relative dielectric permittivity of the LSMCD-derived SBT film decreased with decreasing the film thickness. Leakage current densities lower than $10^{-7}\textrm{A/cm}^2$ at 5V were observed in the SBT films thicker than 125nm.

• 한국표면공학회지
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• 제20권4호
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• pp.144-153
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• 1987

In the case of dipping the Ni-Resist cast iron into molten aluminum with iron content, the thickness of intermetallic compound was remarkably increased with increasing iron content. The thickness was shown by following equation in the range of 1-3% iron content; $x=22.5t^{1/2}+4.47{\cdot}t{\cdot}(Fe%)$. where, x is thickness(${\mu}m$), t the time (minute), Fe% the iron w/o. When the Ni-Resist cast iron was dipped into the molten aluminum containing zinc content, the intermetallic compound thickness was also increased with increasing zinc contents. And thickness was represented by the following equation in the range of 2-10% zinc content; $x=3.46t^{1/2}+0.27{\cdot}t{\cdot}(Zn%)$. However, in the case of dipping the Ni-resist cast iron into molten aluminum with silicon content, the thickness of intermetallic compound was decreased with increasing silicon content, as shown in the following equation; $x=7.17t^{1/2}-0.15{\cdot}t{\cdot}(Si%)$. The intermetallic compound formed onto Ni-Resist cast iron was identified to be $FeAl_3\;and\;Fe_3Al$. As the result of hardness measurement, the peak hardness appeared in the intermetallic compound at near interface of the cast iron and the compound.

• 한국해양공학회지
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• 제27권5호
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• pp.82-87
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• 2013

The icebreaking research vessel ARAON conducted her second ice trial in the Arctic Ocean during the summer season of 2010. During this voyage, the local ice loads acting on the bow of the port side were measured using 14 strain gauges. The measurement was carried out during icebreaking while measuring the thickness of the ice every 10 m. The obtained strain data were converted to the equivalent stress values, and the effects of the ship speed and ice thickness on the ice load were investigated. As a result, it was found that a faster speed produced a larger stress, according to the variation in the peak values below an ice thickness condition of 1.5 m. Meanwhile, the effect of the ice thickness on the ice load was not clear.

• 대한조선학회논문집
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• 제47권5호
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• pp.743-749
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• 2010

Multi-nozzle spray painting procedure of the inorganic zinc shop primer was established in order to obtain uniform film thickness. The shop primer paint prevents the corrosion of steel block during shipbuilding. When the dry film thickness of shop primer is insufficient, rust will be generated on the steel block. Otherwise, thick coating of shop primer may be a problem of weld defect. So, it is important to obtain the uniform film thickness of shop primer. The uniformity of dry film thickness is affected by spray speed, distance from spray gun to target surface and overlapping span of spray path. In order to uniformly maintain coating thickness of shop primer, the coating procedure was established based on the correlation of shop primer spray variables.

• 대한통합의학회지
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• 제6권4호
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• pp.127-137
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• 2018

Purpose : The purpose of this study has been performed to find the effect of horseback riding simulation training on the thickness of abdominal muscles and functional balance in children with down syndrome. Methods : This study included 10 children with down syndrome aged between 7 and 13 years. Both groups received regular neurodevelopmental treatment, also experimental group was performed for additional 15 minutes horseback riding simulation training for twice a week during 8 weeks. We measured the thickness of abdominal muscles by using ultrasonography and measured of functional balance by using Pediatric Berg's Balance for the subjects agreed to the before, after 4 weeks and 8 weeks the training. Results : There were no significant difference in the thickness of the internal oblique and external oblique muscles. There were significant difference in transverse abdominis thickness and functional balance that experimental group had increased average than control group after 4 weeks and 8 weeks training Conclusion : Horseback riding simulation training has a positive effect on the improvement of transverse abdominis muscle thickness and functional balance in children with down syndrome.

• 센서학회지
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• 제27권6호
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• pp.386-391
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• 2018

To analyze the film cooling in a liquid rocket engine, it is necessary to understand the characteristics of the wall-impingement liquid film. We designed an optimal two-dimensional device for measuring the thickness of the liquid film thickness. This device quantitatively measures the liquid-film thickness distribution. In previous liquid-film thickness measuring devices, the liquid film was formed over the entire area of the sensor. However, its formation depended on injection conditions. To compensate for this, optimal resistors are selected. Additionally, saturation variations with partial saturation are analyzed. Furthermore, calibration using the enhanced plate method is conducted with improvements in spatial resolution. The device designed here can be used to analyze the properties of an impingement liquid film with a slit injector. This study can be used for film-cooling analysis in liquid rocket engines.