• Bulletin of Korea Environmental Preservation Association
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• v.29 s.369
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• pp.69-70
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• 2007

올해 다보스포럼에서는 지구 온난화 문제가 가장 큰 화두로 떠오른 가운데 지구를 살리는 8가지 신기술을 보도해 화제다. 미 경제 주간지 '비즈니스2.0' 은 최신호를 통해 '지구를 살리는 8가지 기술' 을 소개했다. 이 잡지가 소개한 기술을 살펴보면 환경오염 방지를 위한 연료, 오염물질 감지센서, 중금속을 흡수하는 나무, 멸종위기 위치 추적시스템 등이다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.6
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• pp.33-40
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• 1982

Although ultrasonic CT is one of the useful techniques for tissue characterization, the reconstructed images, such as the velocity distribution and attenuation constant distribution, are degraded by reflection and refraction of ultrasonic beam. This paper studied the degradation effects on attenuation images using agar gel phantoms which were developed to evaluate ultrasonic CT. We found that the reconstructed attenuation constants at the center of the phantoms were less than the actual values by 0.6 dB/cm when phantom velocity differs by 25 m/s from surrounding saline. We also studied a correction method for refraction and phase cancellation effects, where the correction was made using the maximum value in the received subdata, as obtained by sub-arraying microprobes located at each sampling point. Using this method, we could obtain an improvement in the reconstructed image by the correction on the attenuation effect.