• 한국해안·해양공학회논문집
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• 제21권3호
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• pp.209-215
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• 2009

케이슨식 방파제의 신뢰성해석 시 파고와 조위의 확률변동성을 고려하기 위한 하중면 이용방법을 제안하였다. 케이슨식 방파제 전면에 전달되는 수평파력과 양력을 전면조위와 파고의 일차함수로 추정하였으며 추정한 하중면을 일계신뢰도법을 이용한 신뢰성 해석에 적용하였다. 수치해석에서 하중면을 이용한 케이슨식 방파제의 활동 및 전도 파괴확률을 산정하였으며 몬테카를로 모사법의 결과와 비교하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.93-94
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• 2000

In this work, we proposed a reflective antiferroelectric liquid crystal display (AFLCD) using a half-wave cell whose tilt angle is $22.5^{\circ}$. To check the validity of our design, we fabricated a reflective half-wave AFLC cell of which tilt angle is $24.9^{\circ}$, and measured viewing angle dependent reflectance and VIS reflection spectra. In the results, the half-wave AFLC cell in the reflective configuration exhibits high brightness, high contrast ratio of 20:1.

• 한국소음진동공학회논문집
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• 제20권4호
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• pp.323-330
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• 2010

An efficient wave energy converter with new overtopping flow device on which spiral reefs are attached is proposed by Maritime and Ocean Engineering Research Institute in Korea and its candidate substructures such as monopile, tripod and jacket are designed. This study investigates modal characteristics of the substructures by analyzing natural frequencies and mode shapes. Based on the modal analysis results, relative strength, governing modes and some complementary design strategies of each candidate substructure are compared and discussed considering water depth conditions.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.1000-1013
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• 2014

This paper presents some of the efforts by the authors towards numerical prediction of springing of ships. A time-domain Higher Order Boundary Element Method (HOBEM) based on cubic shape function is first presented to solve a complete second-order problem in terms of wave steepness and ship motions in a consistent manner. In order to avoid high order derivatives on the body surfaces, e.g. mj-terms, a new formulation of the Boundary Value Problem in a body-fixed coordinate system has been proposed instead of traditional formulation in inertial coordinate system. The local steady flow effects on the unsteady waves are taken into account. Double-body flow is used as the basis flow which is an appropriate approximation for ships with moderate forward speed. This numerical model was used to estimate the complete second order wave excitation of springing of a displacement ship at constant forward speeds.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.282-284
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• 2011

Based on graphene oxide and multi-walled carbon nanotube layers, a wireless bi-layer actuator that can be remotely controlled with an electromagnetic induction system has been developed. The graphene-based bi-layer actuator exhibits a large one-way bending deformation under eddy current stimuli due to asymmetrical responses originating from the temperature difference of the two different carbon layers. In order to validate one-way bending actuation, the coefficients of thermal expansion of carbon nanotube and graphene oxide are mathematically formulated in this study based on the atomic bonding energy related to the bonding length. The newly designed graphene-based bi-layer actuator is highly sensitive to electromagnetic wave irradiation thus it can trigger a new actuation mode for the realization of remotely controllable actuators and is expected to have potential applications in various wireless systems.

• 제어로봇시스템학회논문지
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• 제7권3호
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• pp.263-268
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• 2001

A new control scheme s proposed for the control of reactive batch distillation (RBD) column. A nonlinear wave model captures the essential dynamic behavior of the RBD process. The proposed control scheme is based on both Generic Model Control(GNC) and nonlinear wave model. The control scheme uses a profile position of the column as a controlled variable. Ethanol esterification process using RBD is chosen as an example process. Tight control of the distillate purity is obtained with the use of the proposed control scheme.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1365-1371
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• 2009

A new s-wave probe, called "MudFork", has been recently developed and is used in accurate measurements of shear wave velocities of soft soils. In previous researches, some instrumental defects of the probe have been reported. Bending deformation of probe is caused by small section modulus of blades, and open-ended bender elements are vulnerable to damage during penetration. Herein, we improved the MudFork to solve these problems. Field tests at Sinan, Jeollanamdo using the improved MudFork were conducted. Results from MPT are compared with the results from CPT.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1022-1024
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• 2009

Stereoscopic Images provide depth information with the relative distances between the objects in the images. There are many different ways to extract disparity maps from the visible spectral images. For the infrared spectral range, the same approach cannot be utilized for the innate low resolution and colorless features because typical methods require corresponding features between the images. The authors suggest a new approach that makes use of image segmentation to obtain depth information for stereoscopic millimeter-wave images. For image segmentation a selective visual attention model based on the theory of a feature-integration of attention is used. Experimental results show the proposed method provides reasonable depth information for object shape recognition and display.

• 대한전자공학회논문지
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• 제24권5호
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• pp.874-879
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• 1987

An exact wave-optics analysis of wave propagation in thin-film optical waveguide using gyrotropic materials as the substrate or film of the guide is presented for the first time. Based on the Maxwell's equations and the boundary conditions of the guide, the field composition and the boundary conditions of the guide, the field composition and the phase velocity for the eigenmodes of the guide are determined. The field patterns of the guided waves are shown for the eigenmodes of the guides. The present analysos allows a new interpretation in the mode conversion of the thin-film optical waveguides.

• 한국음향학회:학술대회논문집
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• 한국음향학회 2000년도 학술발표대회 논문집 제19권 2호
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• pp.243-246
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• 2000

This paper addresses a new technique of measuring the mean flow velocity not only over the cross sectional area but also along the pipe by exploiting the acoustic plane waves in the pipe. When fluid flows in the pipe and two plane waves propagate oppositely through the medium in it, the flow velocity causes a change of the wave number of the plane waves. The wave number of the positive going plane wave decreases but oppositely that of negative going one increases in comparison to no flow of the medium in the pipe. Theoretical backgrounds of this method are in details discussed and measurement results of the mean flow velocity are illustrated to reveal the feasibility and effectiveness of the suggested technique.