• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.806-809
• /
• 1988

The frequency response characteristics of a bimorph type PZT piezoelectric transducer was investigated. In this study, function generator which generates short burst signal, plane reflection plate and oscilloscope were used to measure the characteristics of piezoceramic ultrasonic transducer. The resonant frequency of a bimorph type piezoceramic transducer which is acquired by using Tone-Burst Method had good agreement with the measured results from spectrum analyzer.

• Journal of the Optical Society of Korea
• /
• v.12 no.3
• /
• pp.147-151
• /
• 2008

This paper proposes a new polarization-independent Sagnac birefringence loop structure-based multiwavelength-periodic filter and presents measurements and analysis of its spectrum. The filter can be used in several schemes by adjusting the orientation angles of two quarter waveplates and the operating characteristics in the reflection type are analyzed including dispersion and polarization mode dispersion at each principal axis. This filter has polarization-independent spectra but a polarization-dependent dispersion, consequently polarization mode dispersion whose values changes with operating schemes.

• East Asian mathematical journal
• /
• v.27 no.2
• /
• pp.101-115
• /
• 2011

Recently, for solving a math problem, and I reflect back, so much emphasis on activities which reflect the activities conducted in schools is necessary to look for. In this study, the 7th Mathematics Curriculum textbooks (10 - a, b) and 7th in mathematics and modification of curriculum textbooks (math) in the reflection type of activities that explore the resulting problems and the measures we discuss are. Therefore, textbooks reflect the type of activities were analyzed before and thinking strategies, and we will examine various types of reflective activities.

• Journal of the Optical Society of Korea
• /
• v.3 no.1
• /
• pp.10-14
• /
• 1999

Via THz Time domain spectroscopy, the characterization of high conductive n-type, 1.31Ω cm silicon can be measured by directly analyzing the multiple reflections using Fabry-Perot theory. The magnitude and phase difference of total transmission show good agreement between theoretical and experimental values over a 2.5 THz frequency range with complex index of refraction and power absorption. The measured absorption and dispersion are strongly frequency-dependent, and all of the results are well fit by a Cole-Davidson type distribution.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2006.08a
• /
• pp.1339-1342
• /
• 2006

We focused on improving of the optical efficiency in the direct BLU. We could achieve the optical efficiency by reducing the thickness of BLU and processing the prism shapes on a reflection sheet. And we were able to reduce the Lamps.

• 한국ITS학회:학술대회논문집
• /
• 2004.11a
• /
• pp.311-314
• /
• 2004

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.74-75
• /
• 2007

• Proceedings of the Optical Society of Korea Conference
• /
• 2007.07a
• /
• pp.269-270
• /
• 2007

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 2002.08a
• /
• pp.263-265
• /
• 2002

외해에서 전파되어 온 파랑은 상대적으로 수심이 얕은 천해로 이동하면서 바닥지형의 영향으로 회절, 굴절, 반사, 천수 및 쇄파 등과 같은 다양한 현상을 경험한다. 본 연구에서는 바닥지형의 변화에 따른 파랑의 반사에 대해 검토하였다. (중략)

• Journal of electromagnetic engineering and science
• /
• v.2 no.2
• /
• pp.128-131
• /
• 2002

A circular polarizer structure of a reflection type, which consists of two sheets of photoetched diople array, is investigated theoretically and experimentally.