• Journal of Internet of Things and Convergence
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• v.2 no.1
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• pp.23-27
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• 2016

There is Generated Moire fringe by fresnel diffraction that explains one of light's physical phenomenon and interference. In this paper, we propose to generate true random numbers by Moire fringe should be used by not pseudo-random number in cryptosystem.

• Journal of the Korean Graphic Arts Communication Society
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• v.15 no.2
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• pp.57-76
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• 1997

A color halftoning is the process of generating halftone images for the different color plans, for example, cyan, magenta, yellow, and black for a offset printing device. A conventional halftone technique, so called AM screening, is simple and easy to implement, but the halftoned dot patterns by using this method is not free for the moire` fringe. Moire` patterns are caused the power spectrum distribution on low spatial frequency domain. To avoid Moire` patterns, the conventional screen require the different screen angles for each color plans. Recently, Ultra-fine and 7 color printing methods are developed to expend the color gamut. In 7 color printing method must be used the halftone technique of random and blue noise characteristic to avoid Moire` fringe.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.1
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• pp.36-45
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• 2010

This paper shows a multiplexing technique to maximize the application of a moire-fringe based fiber optic sensor to lots of structure. Especially, a novel fringe-based fiber optic sensor was proposed to overcome the difficulty of multiplexing of a previous moire-fringe-based fiber optic sensor. The novel fringe-based fiber optic sensor is composed of a single reflective fringe and two optical fibers. Therefore, the multiplexing is easily realized because of the simplicity of optic structure inside the sensor. This paper also proposed four models of the multiplexing techniques. The models are based on a wavelength division multiplexing(WDM) technique and a time division multiplexing(TDM) one. Basically, the models would be profitable for a general extrinsic fiber optic sensor such as the fringe-based fiber optic sensor. Finally, the real optic system was manufactured by using the proposed model and successfully examined to prove the feasibility of the model for the application.

• Journal of the Korea Fashion and Costume Design Association
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• v.11 no.2
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• pp.11-21
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• 2009

Recently, as custom-made demand about female underwear is increased, securing of a various dimension system is urgent, and satisfaction of each customer cannot be heightened with established dimensions. If we could measure shape of a living body with a fast and simple method, the custom-made demand of customers could be satisfied in the underwear as well as a clothing industry by using the method. One of the alternatives is shape measurement of the living body by a Moire fringe method. If we put a grating in front of an object to be measured and illuminate light, a Moire fringe with contour line shape is generated in the object, so we can conveniently measure object shape without touching directly by using the pattern. The Moire fringe and three-dimensional shape of the breast of the living body was acquired by a PMP method using a polygon mirror, and height and bottom width of the breast of the living body were measured by using obtained data in this study. Data of breast shape measurement through a mannequin was collected in a previous step as basic material for measuring the breast shape measurement of the living body. Three women in the twenties were selected as one of methods for measuring breast shape of a woman. As a result of the breast shape measurement of a living body A, it was measured that height of the breast was about 67.24mm and the bottom width was $13781.60mm^2$. This study is expected to contribute for collecting basic data of a female underwear industry and establishing a specification of a dimension system.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.4
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• pp.7-12
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• 2005

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.3
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• pp.103-110
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• 2000

Shaft encoder which encodes the rotational angle of a shaft becomes more important recently due to factory automation and office automation. Although an absolute type encoder is more dsirable due to its convenience an incremental encoder is commonly used because of its cost and technical difficulties Fabricating a high resolution absolute encoder is very diff-cult because the physical size is limited by currently available technology. In order to overcome this difficulty Moire fringe can be used incorporated with gray code. In order to measure the position of fringes which move as the code disk rotates a neural network was developed in this paper. Formerly fringe position is usually measured by a sophisticated software which needs a little long calculation time. However using nerual network method can eliminate such calculation time even though it needs learning job The pro-posed method is verified through several experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.402-406
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• 1995

The shadow moire is one the optical techniques which able to give contour lines of an object with respect to a master grating plane. The moire patterns are issued from the superposition of a grating and its shadow projected on the surface of an object. But in the conventional shadow moire method the reference grating and deformed grating are mutually dependent, it is impossible to obtain uniform phase shifts on the whole field by moving the reference grating. Here we propose ane trial to apply phase shifting to conventional shadow moire. When, in the conventional arrangement, Phase-shifting that is sctually constant regardless of fringe orders is achieved by moving the grating and the light source. Finally we obtained a better result by using this procedure and applied the phase shifting shadow moire to three dimensional measurement.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.49-52
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• 2001

Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topogrphy is very attractive because of it s high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the $2\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the $2\pi$-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.220-223
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• 1997

Moire topography method is a well-known non-contacting 3-D measuement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topography is very attractive because of it's high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the 2x-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the 2x-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

• Journal of the Korean Society for Nondestructive Testing
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• v.15 no.2
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• pp.386-394
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• 1995

The fringes developed by misalignment, an application of Moire method measuring small deformation of specimen, was transformed to frequency function. After that, theory of normalization was applied to derive the equations explaining the relation of the deformation and Moire fringes. Above all, the equations were produced to explain the rotation and increasing of fringes. In addition to that, the relation of fringe number and strain was illustated with the equations deduced from frequency function and geometrical method respectively. These two expressions were more effective than the used ones owing to the one can accommodate the other.