풍동시험에서 지지 장치는 모델을 고정하고 원하는 받음각을 구현하기 위해 사용되지만, 지지 장치가 모델에 작용하는 유동에 간섭효과를 발생시키게 되므로 이에 대한 평가와 보정이 수행되어야 한다. 본 연구에서는 스포츠급 경항공기 1/5 축소 모델의 전기체와 동체 형상에 적용된 배면스팅-반달형 지지장치의 유동간섭 효과를 더미 스팅 방법을 이용하여 공력의 변화를 측정하여 정량적으로 분석하였다. 풍동실험 결과, 하방 스팅의 유동간섭은 전기체 형상의 경우 양력계수에는 2.8%, 항력계수에는 3.4%의 영향을 끼치는 것으로 확인되었다.
Mechanically-alloyed NiAl powder was sintered by Spark-Plasma Sintering (SPS) process. Densification and behavior mechanical property were determined from the experimental results and analysis ,such as changes in linear shrinkage, shrinkage rate, microstructure, and phase during sintering process, Victors hardness, and transver.ie-rupture-strength (TRS). Above 97% relative density was obtained after sintering at 115 for 5 min. Crystallite size determined by the Scherrer method was approximately 50 nm. From the X-ray diffraction analysis it was confirmed that the sintered bodies were composed mainly of NiAl phase together with NiAl phase. Measured Vickers hardness and TRS value were 55510 and 139375 MPa , respectively.
This paper addresses the shear strength based on ACI 318-88 code and proposed equation by Park & Yun for steel fiber coupling beams containing steel fiber.
Based on the study of chloride migration coefficient and hydration heat evolution, it was found that the use of ternary blended cement was effective to achieve desired service life and minimum crack index. On the other hand, a high level of compressive strength is required for marine concrete mix design.