• The Journal of the Korea Contents Association
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• v.11 no.4
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• pp.57-66
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• 2011

At this time, digital cameras are used in art and forensic science. However, the digital camera has some limitations which need to understand of photograph and lighting. It is a useful paper to make an infrared flatbed scanner. The following processes offer an infrared flatbed scanner development. First, the infrared flatbed scanner changes visible fluorescent lamp to infrared LED. Second, it equips a long-pass filter, which is available to pass over 810nm wavelength, on the glass to complete the optimal infrared flatbed scanner. In addition, it must copy from digital camera to computer directly. The infrared digital camera has disadvantage to always irradiate infrared lamp. Because of difference between visible length and infrared length characteristic, they have different focal distance. This devised scanner for solving mentioned problems does not need to irradiate infrared lamp, and there is not a problem about focal point because the depth of field of flatbed scanner is minimum 2mm. Lastly, the infrared flatbed scanner can make high resolution which is 12,800dpi unlike digital camera. Accordingly, the infrared scanner looks forward to be used in many field of study.

• Computers and Concrete
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• v.5 no.2
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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.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.18 no.1
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• pp.59-66
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• 2000

This study describes the precise DTM by image processing method through scanning the positive film of aerial photo using scanner instead of plotter. First, scanned the positive film of aerial photo by drum scanner and flatbed scanner in different resolution, and then compared the height from image processing method using auto correlation method with height which is taken using $50^m{\times}50^m$ grid in 1 :5,000 geographical map. It shows that heights from aerial photo image of high resolution obtained from scanner are comparable to the heights from 1：5,000 geographical map.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.26 no.2
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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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• v.36 no.4
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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.