• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.15-21
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• 1998

Crude enzymes of Trichoderma viride and Phanerochaete chrysosporium were evaluated for their effect to brightness and physical properties of recycled pulp from newspaper and corrugated container board. The brightness of recycled pulp from newspaper increased with crude enzymes from Trichoderma viride and Phanerochaete chrysosporium. The brightness of recycled pulp of corrugated container board increased with crude enzyme from Phanerochaete chrysosporium, but decreased with crude enzyme from Trichoderma viride. The Δbrightness with chemical bleaching of crude enzyme treated pulp was lower than that of heat killed enzyme treated pulp, but the final brightness of pulp was increased. Modification of recycled paper with crude enzymes can result in a substantial increase in physical properties with little no loss in pulp freeness.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.6-11
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• 2003

Refining process is of critical importance unit process for papermaking that influences freeness as well as many mechanical and physical properties of paper. Refining is the process that requires extensive amount of electrical energy. Thus it is required to evaluate the refining process in terms of its influence on fiber and paper properties as well as its effect on energy consumption. In this study, to evaluate the efficiency of refining process the theory of inch contacts has been employed, and the influence of refining processes on fiber and paper properties has been determined and discussed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.34-40
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• 2000

This study was carried out to evaluate the effects of enzymatic treatment on the characteristics of KOCC. Novozym 342 and Pulpzyme HC were used for this purpose. Enzymatic treatment greatly increased the freeness of KOCC and Novozym 342 was more effective. WRV was improved only when KOCC was treated with 0.1% Pulpzyme HC. Pulpzyme HC was more effective to improve the flexibility of fiber(conformability angle) than Novozym 342. Coarseness of fiber was decreased with the enzymatic treatment. Fines content greatly decreased with 0.01% addition of enzymes. Novozym 342 was more effective than Pulpzyme HC for this purpose. Apparent density, tensile index and tear index decreased with enzymatic treatment, but stiffness increased. Especially the decrease of apparent density, tensile index and tear index by the treatment with Novozym 342 was significant than those of Pulpzyme HC. Therefore Novozym 342 will be suitable for the removal of fines and for bulky sheet, otherwise Pulpzyme HC will be good.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 1995.11a
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• pp.200-210
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• 1995

Almost all hash functions suggested up till now provide security by using complicated operations on fixed size blocks, but still the security isn't guaranteed mathematically. The difficulty of making a secure hash function lies in the collision freeness, and this can be obtained from permutation polynomials. If a permutation polynomial has the property of one-wayness, it is suitable for a hash function. We have chosen Dickson polynomial for our hash algorithm, which is a kind of permutation polynomials. When certain conditions are satisfied, a Dickson polynomial has the property of one-wayness, which makes the resulting hash code mathematically secure. In this paper, a message digest algorithm will be designed using Dickson polynomial.

• ETRI Journal
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• v.36 no.4
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• pp.673-681
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• 2014

Fairness of exchange is a significant property for secure online transactions, and a fair exchange scheme is a useful tool for ensuring the fairness of exchanges conducted over networks. In this paper, we propose an ID-based optimistic fair exchange scheme based on the RSA function, one which is designed by combining a well-known RSA-based signature scheme and the (naive) RSA function. Note that the main contribution of this paper is to give the first provably secure ID-based fair exchange scheme based on the RSA function, whose security can be proved under fully formalized security models. Our scheme has the following additional strongpoints. The scheme is setup-free; hence, there is no registration step between a user and an arbitrator. Moreover, the proposed scheme is designed in an ID-based setting; thus, it is possible to eliminate the need for certificates and avoid some related problems.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.605-610
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• 2003

선거를 전자적으로 구성하기 위해서는 비밀성(privacy), 선거권(eligibility) 등과 함께 전체검증(universal verifiability)과 매표방지(receipt-freeness) 속성을 반드시 제공해야 한다. 지금까지 제안된 전자선거 기법은 매표방지와 전체검증을 제공하기 위해 도청 불가능한 채널이라는 물리적인 가정 하에 이루어지거나 하드웨어 장치를 이용하더라도 장치에 대한 신뢰가 가정되었다. 본 논문에서는 믹스 서버나 랜덤마이저의 역할을 스마트카드와 같은 안전한 하드웨어 장치가 하므로 물리적 가정 없이 효율적으로 구현한다. 제안한 시스템은 표를 섞는 과정에서 permutation matrix를 사용하여 증명하므로 증명의 회수가 적고 간단하여 효율적이다. 또한, 지금까지 제안된 대부분의 선거 기법은 ElGamal 암호시스템의 준동형 특성을 이용하여 모든 표를 결합한 다음 해독하여 집계를 계산하는데 이는 이산대수 문제를 효율적으로 해결할 수 있어야 가능했다. 이 논문에서는 ElGamal 암호시스템과 다차잉여 기반 암호알고리즘인 Naccacne 암호알고리즘을 결합하여 표를 인코딩 함으로써 유권자의 수가 많은 선거에 대해서도 다항 시간 내에 집계가 가능하다.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.52-58
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• 2001

The aim of using grape-bagging paper is preventing damages by light and harmful insects during grape growth. The number of using grape-bagging paper has been increasing because advantages of using it have been confirmed. A technology to produce it has not been fully developed yet. In this study properties of the grape-bagging paper were analyzed. Results showed that air-permeability and transmitted light of grape-bagging paper were important. It was tried to see the influence of paper structure on air-permeability, transmitted light and the grapes saccharinity. For making different structure of grape-bagging paper, papers were produced with different freeness levels at several pressure conditions. Coloration time of Campbell grape with new bagging paper started about 5 days earlier than that with usual bagging paper, It was also possible to improve the saccharinity about 0.1-N0.8 Brix. Because new bagging paper has a low apparent density, it affected the saccharinity and coloration time of grape.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.24-29
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• 2007

The stress and strain properties of KOCC were modified to improve the performance of KOCC as a packaging raw material. The refining consistency, refining degree, blending conditions and the grammage of handsheet were varied. The stress-strain properties, tensile energy absorption were measured. The refining improved significantly the stress and strain properties of paper, especially at lower refining consistency. The increase of grammage also contributed to the improvement in the stress and strain of paper. It was also found that the refining, blending and grammage contributed to the increase of tensile energy absorption. However, it is strongly recommended to apply the combination of refining consistency, refining degree and mechanical treatment(blending).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.88-95
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• 2013

Effects of beating and water immersion time on fiber swelling and paper properties were elucidated for the fundamental study of producing high bulk paper. Chemical pulps were beaten for various freeness and the beaten pulp was immersed in water up to 24 hours. Fiber swelling was evaluated by measuring water retention value (WRV). It was found that fiber swelling, bulk and paper strength were quickly changed at the initial stage of beating. Immersion in water did not significantly increase WRV, paper density and strength, implying that soaking in water alone could not effectively swell fiber wall. In order to swell further, hydrogen bonds between fibrils in fiber wall and hence fiber wall structure shall be broken by mechanical force during beating.

• Communications of the Korean Mathematical Society
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• v.23 no.1
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• pp.11-18
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• 2008

For a nef and big divisor D on a smooth projective surface S, the inequality $h^{0}$(S;$O_{s}(D)$) ${\leq}\;D^2\;+\;2$ is well known. For a nef and big canonical divisor KS, there is a better inequality $h^{0}$(S;$O_{s}(K_s)$) ${\leq}\;\frac{1}{2}{K_{s}}^{2}\;+\;2$ which is called the Noether inequality. We investigate an inequality $h^{0}$(S;$O_{s}(D)$) ${\leq}\;\frac{1}{2}D^{2}\;+\;2$ like Clifford theorem in the case of a curve. We show that this inequality holds except some cases. We show the existence of a counter example for this inequality. We prove also the base-locus freeness of the linear system in the exceptional cases.