• 한국콘텐츠학회논문지
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• 제11권4호
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• pp.57-66
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• 2011

현재 디지털 카메라가 적외선 카메라로 예술과 법과학 분야에서 활용 되고 있다. 하지만 디지털 카메라는 촬영이나 광원과 같은 기본적인 이론에 대한 이해가 필요하다는 단점이 있기 때문에 본 논문에서는 적외선 평판 스캐너를 개발하였다. 적외선 카메라의 개발 과정은 다음과 같다. 첫 번째, 가시광선용 형광램프를 적외선 LED로 교체하였다. 두 번째, 완전한 적외선 평판 스캐너를 위하여 유리판 위해 810nm이상 투과가 가능한 롱 패스 필터를 장착하였다. 적외선 디지털 카메라는 촬영을 할 경우 매번 적외선 광원을 조사(Irradiation)해 주어야 하는 번거로움과 가시광선 과 다른 적외선의 특성으로 인하여 생기는 초점문제 그리고 직접 컴퓨터로 옮겨야 하는 작업들이 여전히 존재한다. 이러한 문제를 개선하기 위해 본 논문에서 개발한 적외선 평판 스캐너는 적외선 광원을 개별적으로 조사할 필요가 없으며, 최소 2mm 이상 되는 피사계 심도로 인하여 초점 문제가 없다. 또한 적외선 평판 스캐너는 일반 평판 스캐너와 마찬가지로 12800dpi의 고해상도를 만들어 낼 수 있다는 것 역시 장점으로 작용한다. 본 논문에서 개발한 적외선 평판 스캐너가 많은 분야에서 활용되기를 기대한다.

• Computers and Concrete
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• 제5권2호
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• pp.101-116
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• 2008

The microscopic determination of air void characteristics in hardened concrete, defined in EN 480-11 as the linear-traverse method, is an extremely time-consuming and tedious task. Over past decades, several researchers have proposed relatively expensive mechanical automated systems which could replace the human operator in this procedure. Recently, the appearance of new high-resolution flatbed scanners has made it possible for the procedure to be automated in a fully-computerized and thus cost-effective way. The results of our work indicate the high sensitivity of such image analysis automated systems firstly to the quality of sample surface preparation, secondly to the selection of the air void threshold value, and finally to the selection of the probe system. However, it can be concluded that in case of careful validation and the use of the approach which is proposed in the paper, such automated systems can give very good estimate of the air void system parameters, defined in EN 480-11. The amount of time saved by using such a procedure is immense, and there is also the possibility of using alternative stereological methods to assess other, perhaps also important, characteristics of air void system in hardened concrete.

• 한국측량학회지
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• 제18권1호
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• pp.59-66
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• 2000

본 연구는 해석도화기대신 주사기를 이용해서 항공사진 양화필름을 주사하여 영상처리 기법으로 정밀한 수치지형모델을 구현하고자 하였다. 평상형 주사기와 원통형 주사기를 이용해서 상이한 해상력으로 항공사진양화필름을 주사하여 자동상관기법을 이용해서 영상처리 기법으로 표고를 구하여 1:5,000지형도에서 $50^m{\times}50^m$ 격자를 사용해서 구한 표고값과 비교하였다. 그 결과 주사기로 얻은 고해상도의 항공사진 수치영상을 이용한 경우의 표고는 1:5,000 지형도에 의한 수치지형모델로 구한 표고값에 근접함을 알 수 있었다.

• 치과방사선
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• 제26권2호
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• pp.191-200
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• 1996

This study was performed to determine the adequate resolution and compression method in teleradiology. A digital imaging system using Machintosh IT ci computer, 15' Sony high resolution RGB monitor, Umax Power look flatbed scanner with transparency unit and 12 panoramic radiographs were used. The results were as follows : 1. Relative detectability at the group scanned by 30ddpi, 600dpi and 1200dpi was same as those at the real panoramic radiographs. 2. Perceivable image quality degradation was found at the 25％ of middle quality of JPEG compression. But those were not diagnostically significant. 3. Perceivable image quality degradation was found at the 100％ of low quality of JPEG compression. And 8cases among them were diagnostically significant. On the basis of the above results, it is considered that the adequate resolution in scanning radiographs for teleradiology is 300dpi and compression method is the middle quality of JPEG compression.

• Steel and Composite Structures
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• 제36권4호
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• pp.417-426
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• 2020

Drilling processes in fiber-reinforced polymer composites are essential for the assembly and fabrication of composite structural parts. The economic impact of rejecting the drilled part is significant considering the associated loss when it reaches the assembly stage. Therefore, this article tends to illustrate the effect of cutting conditions (feed and speed), and laminate thickness on thrust force, torque, and delamination in drilling woven E-glass fiber reinforced epoxy (GFRE) composites. Four feeds (0.025, 0.05, 0.1, and 0.2 mm/r) and three speeds (400, 800, and 1600 RPM) are exploited to drill square specimens of 36.6×36.6 mm, by using CNC machine model "Deckel Maho DMG DMC 1035 V, ecoline". The composite laminates with thicknesses of 2.6 mm, 5.3 mm, and 7.7 mm are constructed respectively from 8, 16, and 24 glass fiber layers with a fiber volume fraction of about 40%. The drilled specimen is scanned using a high-resolution flatbed color scanner, then, the image is analyzed using CorelDraw software to evaluate the delamination factor. Multi-variable regression analysis is performed to present the significant coefficients and contribution of each variable on the thrust force and delamination. Results illustrate that the drilling parameters and laminate thickness have significant effects on thrust force, torque, and delamination factor.