• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1993.07a
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• pp.26-28
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• 1993

해안구조물의 설치나 해안환경 문제를 다룰때 가장 필수적인 것이 그 지역에서의 정확한 파랑자료이다. 파랑은 천해로 전파해 옴에 따라 수심 및 지형변화로 인한 회절 및 굴절을 겪으면서 변하게 되므로 복잡한 지형을 가진 해안에서의 정확한 파랑계산은 용이한 일이 아니다. 이러한 파랑변형에 대한 연구는 Berkhoff(1972)가 완경사방정식을 발표한 후 큰 진전을 보이게되는데 이로 인해 종래 개별적으로 다루던 굴절과 회절을 함께 취급할 수 있게 되고 파향선이 교차할때 생기는 불합리한 에너지의 집중(caustics)을 해결할 수 있게 되었다. (중략)

• Journal of the Optical Society of Korea
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• v.8 no.1
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• pp.34-52
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• 2004

Over the past decade the experimental technique of THz time domain spectroscopy (㎔- TDS) has proved to be a versatile method for investigating a wide range of phenomena in the ㎔ or far infrared spectral region from 100 ㎓ to 5 ㎔. This paper reviews some recent results of the Ultrafast ㎔ Research Group at Oklahoma State University using ㎔-TDS as a characterization tool. The experimental technique is described along with recent results on ㎔ beam propagation and how ㎔ beam profiles arise from propagation of pulse fronts along caustics. To illustrate how spatio-temporal electric field measurements can determine material properties over a wide spectral range, propagation of ㎔ pulses through systems exhibiting frustrated total internal reflection (FTIR) are reviewed. Finally two potential metrology applications of ㎔-TDS are discussed, thin film characterization and non-destructive evaluation of ceramics. Although ㎔-TDS has been confined to the research laboratory, the focus on application may stimulate the adoption of ㎔- TDS for industrial or metrology applications.

• Journal of Chest Surgery
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• v.29 no.4
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• pp.420-426
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• 1996

We previously reported 344 cases of esophageal reconstruction for caustic esophageal stricture between 1959 and 1982, and this is the second report of 69 cases during 12 year period from Jan. 1983 to Feb. 1995. There were 32 males and 37 females, ranging in age from 4 to 65 years(mean 36.4 years). Caustic materials were acid in 37 (53.7%) and alkali in 31 (44.9%). All cases underwent colon interposition without esophageal resection except 3 cases of cancer complication which were resected through thoracotomy. In 64 cases isoperistaltic right colon with teminal ileum interposition were performed, and 5 cases were interposed with left colon either isoperistaltic (2 cases) or antiperistaltic (3 cases) method. Anastomotic leakage was the most frequently encountered c mplication (14.4%, 10 cases), and they were 11.6%(8 cases) from cervical, 2.8% (2 cases) from ileocolostoma. Overall operative mortality was 2.9% (2169), main causes of death were sepsis due to graft necrosis and mediastinitis. During 6 months to 12years (mean 2.Syears) follow-up of survived 67 cases, 88.1% (59 cases) ate normally, 7.5% (5 cases) complained of moderate dysphagia (eating liquid diet), and 4.5% (3 cases) were unable to eat by mouth. In our experience, reconstruction of the esphagus with the colon is a satisfactory method that can be accomplished with acceptable morbidity and mortality. The right colon is a durable and functional esophageal substitute.