• Journal of computational fluids engineering
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• v.18 no.3
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• pp.42-50
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• 2013

The supersonic airplane with flapped biplane, Busemann biplane equipped flap, is superior to drag and noise reduction due to wave cancelation effect between upper and lower airfoils. In this study, it is numerically calculated and analyzed the lift, drag and lift to drag ratio of flapped biplane with respect to various the length and angle of the flap. Euler solver of EDISON CFD, web based computational fluid dynamic solver for the purpose of education, is employed. Depending on the length of the flap, lift and drag increase linearly, and there exists the optimum flap angle which maximize the lift-to-drag ratio at the freestream mach 2.0 on-design condition. The predictable relational expression is driven as liner equation. As a results of comparison with drag of flapped biplane, Busemann biplane, and diamond airfoil with the same lift, the drag of flapped biplane is 88.76% lower than that of the Busemann biplane and 70.67% lower than that of the diamond airfoil. In addition, the change of pressure is compared to confirm the noise reduction effect of flapped biplane at h/c=5 of lower airfoil. The shock strength of flapped biplane is smaller than that of other airfoils.

• Ocean and Polar Research
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• v.24 no.3
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• pp.189-196
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• 2002

A multichannel seismic survey was conducted in the southern Ayu Trough which is the only spreading boundary between the Philippine Sea and Caroline plates. The seismic system used in this study comprises of 2.46-l sleeve gun and a 12-channel streamer with a group interval of 6.25m. Migration technique was used to analyze seismic velocity, and poststack depth migration was applied to the stacked data. The sediment thickness obtained from the depth section tends to increase with distance from the spreading axis. Sedimentation rates are poorly constrainted in the study area. The apparent half-spreading rates estimated from the sediment thickness and sedimentation rate from DSDP hole on the caroline plate are 4.7mm/yr and 7.9mm/yr at $1^{\circ}24'N\;and\;0^{\circ}42'N$, respectively, which are fester than Previously suggested. On the basis of new oblique spreading geometry, the recalculated spreading rates are 5.4mm/yr and 9.1mm/yr at $1^{\circ}24'N\;and\;0^{\circ}42'N$, respectively. Seismic sections show that the topography is asymmetric across the Ayu Trough and the acoustic basement is rough. These features are consistent with the earlier suggestion that the Ayu Trough is a slow-spreading divergent boundary. A detailed examination of seismic profiles away from the axis shows that sediments can be divided into two layers which implies a possible change in the spreading rate anuor sedimentation condition during the formation of the trough.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.9
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• pp.904-913
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• 2001

The objective of this study was to investigate the characteristics of jet flow and heat transfer caused by trapezoid rods array in impinging jet system. In this study, trapezoid rods have been set up in front of flat plate to serve as a turbulence promoter. The bottom width of trapezoid rod was W=4, 8 mm and oblique angle were 80$^{\circ}$. The space from rods to the heating surface was C=1, 2, 4 mm, the pitch between each rods was P=30, 40, 50 mm, and the distance from nozzle exit to flat plate was H=100, 500 mm. This results were compared with the case without trapezoid rods. As a result, when rods are installed in front of the impinging plate, the acceleration of the jet flow and the eddies due to the rods seem to contribute to the heat transfer enhancement. Among test conditions, the heat transfer performance was best for the condition of W=8 mm, C=1 mm, P=30 mm and H/B=10. The maximum heat transfer rate is about 1.9 times larger than that without trapezoid rods.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.5
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• pp.450-456
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• 2006

In this paper, we report the changes of morphology, transmittance and photoluminescence (PL) in hydrogenated amorphous $As_{40}Ge_{10}Se_{15}S_{35}$ thin films, thermally deposited at the vapor incidence angles (${\theta}$) of $0^{\circ},\;45^{\circ}\;and\;80^{\circ}$. The hydrogenation was carried out under the condition of a $H_2$ pressure ($P_H$) of 20 atm and an annealing temperature range, $T_{Anneal}$ of $150^{\circ}C{\sim}210^{\circ}C$. A columnar structures with an inclination angle of approximately $65{\sim}70^{\circ}$ was formed in $80^{\circ}$-deposited films and then the columnar was broken after hydrogenation. Transmittance increases with an increase of deposition angle and by the hydrogenation. In particular, a broad PL band on the extended region is observed in obliquely deposited films and it increases during the hydrogenation.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.3
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• pp.175-180
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• 2016

In this study, we proposed an optical compensation method to improve the symmetricity of contrast ratio for wide viewing angle IPS (in-plane switching) LCD. First, the phase retardation depending on the thickness of compensation film is calculated, and then the phase change is presented at the $Poincar{\acute{e}}$ sphere. The phase retardation and the polarization state of the light passing through the optical elements are caculated by using the EJMM (extended Jones matrix method). In addition, the transmittance and the contrast countour are also calculated by using the Berremann's $4{\times}4$ matrix method. The simulation is carried out for a IPS LC cell with positive A/C/A compensation film. From the standard deviation of the contrast ratio, we confirmed the symmetricity at each viewing angle is inversely proportional to the standard deviation and calculated the optimum design condition of the uniaxial compensation film for the IPS LCD.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.13-18
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• 2010

Extreme ultraviolet (EUV) lithography using 13.5 nm wavelengths is expected to be adopted as a mass production technology for 32 nm half pitch and below. One of the new issues introduced by EUV lithography is the shadowing effect. Mask shadowing is a unique phenomenon caused by using mirror-based mask with an oblique incident angle of light. This results in a horizontal-vertical (H-V) biasing effect and ellipticity in the contact hole pattern. To minimize the shadowing effect, a refilled mask is an available option. The concept of refilled mask structure can be implemented by partial etching into the multilayer and then refilling the trench with an absorber material. The simulations were carried out to confirm the possibility of application of refilled mask in 32 nm line-and-space pattern under the condition of preproduction tool. The effect of sidewall angle in refilled mask is evaluated on image contrast and critical dimension (CD) on the wafer. We also simulated the effect of refilled absorber thickness on aerial image, H-V CD bias, and overlapping process window. Finally, we concluded that the refilled absorber thickness for minimizing shadowing effect should be thinner than etched depth.

• International Journal of Ocean System Engineering
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• v.3 no.2
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• pp.61-67
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• 2013

In this study, wave spectrum based fatigue analyses are studied for Turkey's adjacent coastal seas by using Maestro finite element analyzing software. Palmgren-Miner's method is used to obtain the fatigue safe life time. Palmgren-Miner's method was selected for the fatigue analyses because of its good acceptance of data from almost all classification societies such as Germanischer Lloyd, the American Bureau of Shipping, Det Norske Veritas, etc. The maximum stress regions of the structures are obtained by using finite element analyses, and the results are compared with the endurance limit of the W$\ddot{o}$hler diagram of AA5059 H321 aluminum alloy. The wave characteristics table given in this article is used to obtain the number of cycles for each sea condition. By using the wave characteristics table, the wave lengths, wave speeds, and cycles are obtained. This study is performed to estimate the lifetimes of a semi-swath type coast guard boat and/or commercial yacht projects, which are produced by using AA5059 H321 aluminum alloy, under different sea environment conditions. Fatigue examinations are performed for both head seas and oblique seas.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.331-336
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• 1983

Cor triatriatum is a rare congenital malformation of the heart, in which a septum stretches in a transverse or oblique plane through the left atrium, thus separating it into two compartments. The upper one connects with the pulmonary veins, and the lower one connects with the left ventricle. Due to the rarity of, and great difficulty in-diagnosing, cor trlatrlatum, data On the surgery of this disease are of necessity very limited and so accurate pre-operative diagnosis was very difficult to make. `We experienced a case of the cyanotic congenital heart disease which was diagnosed as a large atrlal septal defect with streaming venous blood from inferior vena cava to left atrium through atrial septal defect in August, 1982. We found that there were transverse septum in the left atrium through atrlal septal defect, the pulmonary venous drainage were located in the upper chamber of the left atrium, and the lower chamber was connected with the left atrial appendage, mitral valve and `left ventricle. But our case had not any opening in this transverse septum and the right atrium was connected with the upper chamber of the left atrium through the upper part of the atrlal septal defect, and was communicated with the lower chamber of the left atrium through the lower part of the atrlal septal defect. We excised the transverse septum and repair this atrial septal defect with Woven Dacron patch accompanying with the drainage of coronary sinus to right atrium. The post-operative course was not eventful and he was discharged with good result on the post-operative 8th day, and has been in good .condition up to now for longer than 10 months.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.2
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• pp.181-187
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• 2019

Purpose: The purpose of this study was to investigate the activity of respiratory muscle and lung capacity during deep breathing with electrical stimulation of the vagus nerve. Methods: This study was conducted on 30 healthy adults in their 20s. Subjects were randomly performed to deep breathing or deep breathing with vagus nerve electrical stimulation. All subjects' diaphragm and internal oblique muscle activity were measured during deep breathing by electromyography, and lung capacity was measured by spirometry immediately after beep breathing. In the vagus nerve stimulation method, the surface electrode was cut into the left ear and then electrically stimulated using a needle electric stimulator. Results: The activity of diaphragm was significantly increased in deep breathing with vagus nerve electrical stimulation than in deep breathing. However, lung capacity did not show any significant difference according to the condition. Conclusion: Vagus nerve electrical stimulation could induce diaphragm activity more than deep breathing alone. Deep breathing with vagus nerve electrical stimulation may enhance the activity of the respiratory muscles and is expected to be an effective treatment for the elderly or COPD patients with poor breathing ability.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.55.2-55.2
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• 2019

The firehose instability is driven by a pressure anisotropy in a magnetized plasma when the temperature along the magnetic field is higher than the perpendicular temperature. Such condition occurs commonly in astrophysical and space environments, for instance, when there are beams aligned with the background magnetic field. Recently, it was argued that, in weak quasi-perpendicular shocks in the high-β intracluster medium (ICM), shock-reflected electrons propagating upstream cause the temperature anisotropy. This electron temperature anisotropy can trigger the electron firehose instability (EFI), which excites oblique waves in the shock foot. Scattering of electrons by these waves enables multiple cycles of shock drift acceleration (SDA) in the preshock region, leading to the electron injection to diffusive shock acceleration (DSA). In the study, the kinetic properties of the EFI are examined by the linear stability analysis based on the kinetic Vlasov-Maxwell theory and then further investigated by 2D Particle-in-Cell (PIC) simulations, especially focusing on those in high-β (β~100) plasmas. We then discuss the basic properties of the firehose instability, and the implication of our work on electron acceleration in ICM shock.