• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.121-127
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• 2002

This research was carried out to develop the Hanji(Korean paper) sludge·wood particle composite utilizing the waste sludges occurring from the making process of Hanji(Korean paper). At the research, four mixing ratios of white or black sludge to wood particle(10:90, 20:80, 30:70 and 40:60), three types of the resin adhesives(PMDI, urea and phenol resin) and three levels of the densities(0.60, 0.75 and 0.90) were designed to investigate the mechanical properties of Hanji(Korean paper) sludge·wood particle composite. In the white and black sludge·wood particle composites, bending properties(MOR, MOE) showed the decreasing tendency according to the increase of sludge additive, but it was clearly increased with the increase of specific gravity. Also tensile strength had the same tendency as in these bending properties. The internal bond strength of white sludge·wood particle composite had no tendency, but that of black sludge·wood particle composite was decreased as an increase of Hanji sludge additive.

• Journal of the Korean Wood Science and Technology
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• v.27 no.2
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• pp.23-30
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• 1999

This study was carried out to develop the Korean paper(Hanji) sludge-wood fiber composite boards utilizing the relinquished sludges occurring from the making process of Korean classic paper Hanji. The bark of paper mulberry(Broussonetia kazinoki Sieb.) has been used as a raw material since past hundreds and thousands years. Korean paper(Hanji) sludge was divided into two kinds, the one was the white sludge from the first stage and the other was the black sludge occurring from the final stage of Korean paper(Hanji) making. Four levels of the mixed ratio of each white or black sludge to wood fiber(10:90, 20:80, 30:70 and 40:60), three levels of the resin adhesives(PMDI, urea and phenol resin) and three levels of the density(0.60, 0.75 and 0.90) were designed to investigate the physical properties of Korean paper(Hanji) sludge-wood fiber composite boards. From the results and discussion, it could be concluded as follows : 1. In the white sludge-wood fiber composite board, the thickness swelling was not affected by the specific gravity and sludge additive of composite boards, but among the resin adhesives PMDI resin showed the best dimensional stability. Water absorption was superior in urea resin, secondly PMDI resin and very poor in phenol resin. 2. In the black sludge-wood fiber composite board, thickness swelling was superior in PMDI resin but very poor in phenol resin. In water absorption, PMDI and urea resin showed good results, regardless of specific gravity or sludge additive, but phenol resin showed poor results. 3. From the results and discussion of physical properties it is suggested that the white sludge-wood fiber composite boards bonded with PMDI or black sludge-wood fiber composite boards bonded with urea resin were made possibly with similar or better properties. compared with general fiberboard until the addition of 20% sludge into wood fiber.

• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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• pp.51-56
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• 1998

The bast fiber of paper bush misumada have been cultivated in south coast bay of the Korean peninsula were not used to handmade painting paper. Therefore, in using the bast fiber of paper bush misumada manufactured handmade painting paper, tested absorption speed, blot characteristics and organic functions. The results are summarized as follows; The handmade painting paper manufacured only the bast fiber of paper bush misumada proper to the absorption speed of China ink, didn't have difference of the length and width for blot. And it was most fitted to east writing-and-painting using. Also the flexibility excell, and light and shade in overpainting directly appeared, and fitted to black-and-white drawing. And the using increase plan of the paper bush misumada demanded.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.235-238
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• 2007

eMagin's unique OLED-on-silicon microdisplay technology is unique and is based on small molecule white OLED with color filters using a top emitter structure. This paper will present results of recent improvements in the technology including improved lifetimes and uniformity and will feature an SVGA resolution full color microdisplay that is 0.44 inches diagonal.

• Journal of Conservation Science
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• v.35 no.5
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• pp.385-391
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• 2019

In order to examine the material characteristics of a black and white photograph of the Borobudur temple, in Indonesia, several analyses were conducted. A sample was taken from a black and white photograph; microscopy, Fourier transform-infrared spectroscopy, scanning electron microscopy/energy dispersive spectroscopy, X-ray diffraction, and X-ray fluorescence analyses showed that the black and white photograph was composed of four layers including a paper substrate, baryta, binder and surface layers. It was confirmed that the substrate was paper made of cellulose fiber from Cannabis sativa, the baryta layer was made of barium sulfate(BaSO₄) in powder form, the binder was an emulsion containing silver halide, and the surface protective layer was made of gelatin. Since photographs have different characteristics and require different preservation environments depending on the material of construction, it is necessary to study various black and white photographic material characteristics corresponding to each time period.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.7
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• pp.1292-1302
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• 2009

In this paper, we proposed Single Tone Detection Algorithm for prevent decoloration and color distortion of single tone image in auto white balance of mobile phone camera. Conventional auto white balance which accomplish very well using complex color images, but there are some problems if input images are single tone image or included large part of single tone. If input images are singlet one, or included large part of single tone, which cause decoloration or distorted color in output images. In this paper, we proposed single tone detection algorithm using color histogram data for solve decoloration or distorted color problems. If this algorithm is applied to auto white balance, it will be improvement in auto white balance.

• Journal of Conservation Science
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• v.23
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• pp.39-51
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• 2008

Adding chemical additives in bamboo paper making procedure in China became common in last decades to increase productivity. Supply of repair paper for paper based artefacts became more and more difficult due to this tendency. Furthermore, stains and spots on paper which happen to appear during dying procedure make it difficult to use modern bamboo paper for repair treatment. In this research, lime fermentation and sun bleaching were main elements which affect texture and color of paper. Impurities, however, add some effects on paper quality. Less thouroughly washed raw materials after fermentation also affects texture of paper substrate. One most significant impurity is lime. Minimum residue of lime can make stains and spots after dying. Reproduction of white bamboo paper would become useful resource in various conservation treatments as a repair paper, and also, for reproduction of paper woven painting. However, further research to improve quality at early stage of paper making procedure in China required.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.5
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• pp.751-763
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• 2022

With the recent increase in spending growth in the IoT sector worldwide, the importance of lightweight block ciphers to encrypt them is also increasing. The lightweight block cipher PIPO algorithm proposed in ICISC 2020 is an SPN-structured cipher using an unbalanced bridge structure. The white box attack model refers to a state in which an attacker may know the intermediate value of the encryption operation. As a technique to cope with this, Chow et al. proposed a white box implementation technique and applied it to DES and AES in 2002. In this paper, we propose a white box PIPO applying a white box implementation to a lightweight block cipher PIPO algorithm. In the white box PIPO, the size of the table decreased by about 5.8 times and the calculation time decreased by about 17 times compared to the white box AES proposed by Chow and others. In addition, white box PIPO was used for mobile security products, and experimental results for each test case according to the scope of application are presented.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.40-44
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• 2000

A microscopic study was carried out to get the fundamental informations for the ozone deinking technology. The differential interference microscopic observation showed that ozone treatment was helpful to detach the toner ink from the surface of pulp fiber. The modifications of fiber surfaces by ozone treatment were observed with scanning electron microscope. Modification of fiber surfaces was not severe at the early stage of ozone treatment, but it increased with ozone treatment time and pulp consistency, Therefore, it would be possible to improve the properties of deinked pulp by controlling the condtion of ozone treatment.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.7
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• pp.605-613
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• 2014

Scanning white-light interferometry is an important measurement option for many surfaces. However, serious profile measurement errors can be present when measuring free-form surfaces being highly curved or tilted. When the object surface slope is not zero, the object and reference rays are no longer common path and optical aberrations impact the measurement. Aberrations mainly occur at the beam splitter in the interference objective and from misalignment in the optical system. Both effects distort the white-light interference signal when the surface slope is not zero. In this paper, we describe a modified version of white-light interferometry for eliminating these measurement errors and improving the accuracy of white-light interferometry. Moreover, we report systematic errors that are caused by optical aberrations when the object is not flat, and compare our proposed method with the conventional processing algorithm using the random ball test.