• Current Optics and Photonics
• /
• 제7권3호
• /
• pp.248-253
• /
• 2023

An efficient global optimization approach for a periodic plasmonic nanoslit array based on extraordinary optical transmission within an acceptable time range is proposed using 𝚀 factor analysis method. The particle swarm optimization is employed as a global optimization tool. The figure of merit is defined as a product of transmission peak value and 𝚀 factor. The design variables are the slit width, height, and period of the slit array, respectively. The optical properties such as transmission spectrum and bandwidth are calculated rigorously using the finite element method.

• Structural Engineering and Mechanics
• /
• 제37권3호
• /
• pp.285-296
• /
• 2011

The plane crack-contact problem for an infinite elastic layer with two symmetric rectangular rigid stamps on its upper and lower surfaces is considered. The elastic layer having an internal crack parallel to its surfaces is subjected to two concentrated loads p on its upper and lower surfaces trough the rigid rectangular stamps and a pair of uniform compressive stress $p_0$ along the crack surface. It is assumed that the contact between the elastic layer and the rigid stamps is frictionless and the effect of the gravity force is neglected. The problem is reduced to a system of singular integral equations in which the derivative of the crack surface displacement and the contact pressures are unknown functions. The system of singular integral equations is solved numerically by making use of an appropriate Gauss-Chebyshev integration formula. Numerical results for stress-intensity factor, critical load factor, $\mathcal{Q}_c$, causing initial closure of the crack tip, the crack surface displacements and the contact stress distribution are presented and shown graphically for various dimensionless quantities.

• 한국전자파학회논문지
• /
• 제19권5호
• /
• pp.501-505
• /
• 2008

이 논문에서는 휴대 장치의 지상파 DMB용 안테나로 다중 권선 loop 안테나를 제안한다. 제안된 안테나는 크기가 작으면서도 지상파 DMB 대역에서 충분한 수신 전력을 확보하도록 권수는 80회, 그리고 직경은 4 mm로 하였으며, 또한 높은 전달 함수 특성을 갖도록 품질 계수를 1로 하였다. 제작된 안테나는 길이가 30 mm로 소형이며, 이득은 약 -15 dBd로 길이 190 mm의 상용 지상파 DMB 모노폴 안테나와 비슷한 수신 능력을 가짐을 측정을 통해 확인하였다.