• Journal of the Korean Institute of Telematics and Electronics
• /
• v.27 no.3
• /
• pp.1-6
• /
• 1990

When TE waves incident to the infinite conductor grating plane, current distributions on the strip is found by the spectral domain analysis and the moment method. Current distributions on the strip as the parameter of incident angle of waves are calculated for the grating plane of which strip space is $0.05{\lambda}{\sim}5{\lambda}$, and of which the ration of strip width to its space is 0.4 - 0.8 . In order to varify the validity of the present method, the numerical results are compared with other method.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.8 no.1
• /
• pp.17-22
• /
• 1983

Scattering of obliquely incident plane electromagnetic waves by an isotropic plasma coumn which is moving uniformly in the perpendicular direction to its axis is treated analytically on the basis of Lorentz transform and boundary conditions. The scattered field, the total scattering cross-section, the rader cross-section, and the angular distribution of the scattered power for the incident plane waves polarized arbitrarily are derived to find the function of the moving velocity of the plasma column and of the angle of the incident plane waves and to find the scattered field of the H-waves more distinguishable than the E-waves.

• Journal of the Korean Vacuum Society
• /
• v.8 no.1
• /
• pp.55-62
• /
• 1999

Monte Carlo ion scattering program is improved with the single scattering methods where the total cross section and the mean free path are calculated as a function of atomic density during ion scattering in matter. The relations among the parameters of incident ions and substrate materials are investigated to the sputtering phenomena. The sputtering yield has been analyzed with the dependence on the incident ion species and energy, incident angle, and surface binding energy. The energy distribution of sputtered particles is discussed.

• Journal of the Korean institute of surface engineering
• /
• v.20 no.2
• /
• pp.43-48
• /
• 1987

Chromium and Aluminum films were deposited by evaporation technique in $3{\times}10^{-6}$ mbar vacuum level at the incident angles ranging from $0^{\circ}\;to\;60^{\circ}$ with various evaporation rates. We measured the sheet resistances and light transmittances, and observed diffraction patterns by TEM of these films. Relations among diffraction patterns, sheet resistances and light transmittances were discussed. The sheet resistances and light transmittances were shown the lowest values at 25$^{\circ}C$ of incident angle for all kinds of evaporation rates.

• Journal of Ocean Engineering and Technology
• /
• v.35 no.2
• /
• pp.113-120
• /
• 2021

In order to perform a precise wave tank experiment, it is necessary to maintain the incident wave generated by the wavemaker in a steady state and to effectively remove the reflected waves. In this paper, a combined sloping-wall-type punching plate wave absorber was proposed to attenuate reflected waves effectively in a two-dimensional mini wave tank. Using the four-point reflection separation method, the reflected waves were measured to determine the reflection coefficients. Experiments were conducted under various punching plate porosities, sloping plate angles, and incident wave conditions to evaluate the performance of the combined punching plate wave absorber. The most effective wave absorbing performance was achieved when the porosity was 10% and the inclination angle of the punching plate was 18.6° under the present condition. It was also found that the installation of the sloping plate could improve the wave attenuation performance by generating the shoaling effect of the incident wave.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.6
• /
• pp.477-480
• /
• 1998

In this paper, we investigated the liquid crystal(LC) alignment and generation of pretilt angle by using photo-alignment techniques on two kinds of polyimide(PI) surface, It was found that the uniform alignment for nematic(N) LC is obtained in a cell with slanted UV light irradiation on PI surface without side chain. We successfully observed that the pretilt angle of NLC is generated about $3^{\circ}$ with an incident angle of 70 degree on the PI surface without side chain. It is considered that the pretilt angle generation in NLC is attributed to interaction between the LC molecules and the polymer surfaces.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.6
• /
• pp.759-768
• /
• 2019

The extended Tanimoto formula has been widely used to estimate the stability for the toe protection of the composite structure. However, the extended Tanimoto formula usually over-estimates armor weight when the incident waves approach the structure obliquely because the formula incident originally considered the normally incident wave cases. In this study, three-dimensional hydraulic model experiments were conducted to investigate the horizontal wave velocity under monochromatic and random wave conditions to investigate the prediction capability of the extended Tanimoto formula under the different incident wave angle conditions. The maximum horizontal wave velocity was measured near the toe for the normally incident wave condition. In the case of obliquely incident waves, the maximum horizontal wave velocity was measured under the stem wave generation condition. The results of the experiments showed a good agreement with the results by Takahashi et al.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.21 no.4
• /
• pp.334-344
• /
• 2009

In the present paper, analytic solutions are derived for scattering of obliquely incident waves by a semi-infinite breakwater or a breakwater gap of partial reflection. In order to examine the appropriateness of the derived solutions, they are compared with the solutions derived by McIver in 1999 and Bowen and McIver in 2002 for a semi-infinite breakwater and a breakwater gap, respectively, in the case of perfect reflection. The derived analytic solutions are used to investigate the effect of reflection coefficient of the breakwater and wave incident angle upon the tranquility at harbor entrance. The tranquility is deteriorated by the reflected waves as the reflection coefficient increases and as the waves are incident more obliquely.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.4B
• /
• pp.405-412
• /
• 2006

This study investigates the characteristics of stem waves along a vertical wall generated by obliquely incident monochromatic waves through laboratory experiments conducted in a wave basin and numerical simulations using parabolic approximation equations. The investigation is focused on the nonlinear effect of incident waves on the propagation characteristics of stem waves. Numerical results are compared with laboratory measurements and good agreements are obtained. The main results of this study show that the normalized stem wave height along the wall decreases and the stem width increases as the angle of incident waves decreases or the nonlinearity of the incident waves increases.

• Journal of KSNVE
• /
• v.7 no.6
• /
• pp.945-952
• /
• 1997

This paper shows the feasibility of the suggestion that the angle distribution of incident sound to panels might be gaussian, instead of the conventional uniform distribution in the analysis of transmission loss of panels. To prove the suggestion, the problems with the diffuse sound field in a reverberation room are examined by case studies and the comparision of the prediction with the measurement of sound transmission loss of walls are performed. The results of the comparision show good agreement between the two values.