• 펄프종이기술
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• 제41권2호
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• pp.26-33
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• 2009

A new testing method to evaluate the deposition potential of white pitch was developed. The new method involves depositing the potential white pitch particles on the air bubble covered plastic film in the pitch deposit tester (PDT) developed by KRICT and analysing the deposited area of white pitch using an image analyzer. In addition, the effect of two important factors (pH and calcium hardness) on white pitch deposition potential was elucidated. When pH of the coated broke stock was increased from neutral to alkali or the calcium hardness of the stock was decreased, the pitch deposit area was decreased, implying that these two factors have to be controlled during the evaluation of pitch deposition potential. It was found that hydrophobicity of the surface of latex binding films repulped is a key factor influencing white pitch deposition.

• 한국과 국제사회
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• 제3권1호
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• pp.39-76
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• 2019

본 논문은 중국의 국방 안보백서 발간의 추이와 함의를 분석하기 위한 것이다. 이를 위해 중국의 국방 안보백서의 발간경위 및 구성, 시진핑 시기의 국방 안보백서의 요지와 함의의 순서로 살펴본 후 결론을 도출해 본 것이다. 중국 국방부는 1998년 이후 2010년까지 2년 주기로 7권의 "중국의 국방"을 발간했다. 그리고 중국 국방부는 이미 1995년 국방관련 주제의 백서 "중국의 무기통제와 군축"을 처음 발간한 데 이어, 2013년 "중국 무장역량의 다양한 운용", 2015년 "중국의 군사전략"의 3권의 국방관련백서, 그리고 2017년 "중국의 아시아 태평양 안보협력정책"이라는 1권의 안보백서를 발간했다. 모두 중국의 전략적 계산을 반영한 프로파간다라는 공통적 특징을 지니고 있다. 중국이 전향적으로 국방백서를 발간하기 시작한 데는 (1)미국 등 주변국의 군사적 투명성 요구에 대한 압력, (2)'중국위협론'의 불식, (3)중국의 군사 현대화의 성과에 대한 자신감 등 복합적 요인이 작용한 것으로 보인다. "중국의 꿈은 강국의 꿈이고 강국의 꿈은 강군건설이 필수이다."라는 시진핑의 의지가 담긴 '적극적 방어전략' 및 강대강전략은 주변국에게 안보적 우려감을 증폭시키고 있다. 튼튼한 한 미 안보공조관계를 유지 강화해 나가는 한편, 한중경제협력관계도 조화롭게 추진해 나가는 헤징전략이 우리에게 요구된다.

• 펄프종이기술
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• 제47권6호
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• pp.98-105
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• 2015

Demands of thermal recording paper have been increased significantly by increase in usage of invoice, fax, and label. Thermal recording paper was mainly made based on virgin fiber. It is necessary to find a suitable alternative to virgin fiber in terms of environment protectional resources conservation. In this paper, deinking properties of different recovered papers were analyzed in order to use the recovered paper as raw material of thermal recording paper. Recovered paper were ONP, OMG and white ledger. Flotation reject of OMG was high because inorganic pigments in coating layer could be removed by upstream of froth. Brightness of white ledger and OMG were much higher than that of ONP. Therefore, properties of pulp made from the recovered paper could be enhanced with increase in blending ratio of white ledger and OMG. However, blending ratio of OMG caused the increase of flotation reject. Consequently, the optimum blending ratio of ONP, OMG, and white ledger was 3:3:3 for eco-friendly thermal recording paper. Under the condition, brightness was about 70% and ERIC was below 300 ppm.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.133-134
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• 2017

The In the experiment on flow using sand walls, when white clay+sand was mixed with glutinous rice, traditional paper and seaweed as adherents and preventive measures for cracks, the flow was higher than other sand wall mortars. This indicates that it is effective in improving flow. Moreover, in terms of strength, a mix of white clay+sand, traditional paper and flour had a greater strength than a mix of white clay+sand, straws and flour. In the experiment to test for cracks and shrinking during drying, a composition of white clay+sand+traditional paper showed fewer cracks and less shrinking than the walls where straws were mixed in.

• 펄프종이기술
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• 제37권4호통권112호
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• pp.38-43
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• 2005

Natural Com Starch(NCS) spray system has been widely used In multiply board mill for the better bonding strength between board layers. However the unsuitable NCS spray system could lead to a drop in plybond efficiency of multiply board. It could also result in the accumulation of unretained-starch in the white water system, which could not only rise in BOD and COD level but also reduce the effects of rosin-alum sizing system and other additives. In this study, the simple and rapid method by UV-spectroscopy for measuring the starch contents in the white water was proposed, and the quantitative analysis for dissolved starch content in white water was carried out in two kinds of board production process. It could be confirmed that about 150 ppm of oxidized starch was retained in white water dewatered from undertop ply of multiply board process, and about 470 ppm of natural starch was dissolved in white water originated from unsuitable spraying system in the multiply board production lines for cup base paper.

• Journal of the Korean Wood Science and Technology
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• 제32권5호
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• pp.86-92
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• 2004

본 연구는 백탄보드와 오버레이 백탄보드를 비포름알데히드계 수지 접착제를 사용하여 습식공법으로 제조하고, 백탄보드의 포장용 상자로서의 기능을 검토하기 위하여 에칠렌가스 흡착과 딸기의 보관성을 측정하였다. 그결과, 백탄보드의 에칠렌 가스 흡착성능은 종이보다 월등히 좋았고 백탄 자체보다 높았으며, 오버레이 백탄보드와 비오버레이 백탄보드간 가스흡착성능은 차이가 없었다. 종이상자와 PVC상자 내 딸기와 백탄보드상자 내 딸기의 잿빛곰팡이 발생시간을 비교한 결과, 각각 2일 후, 4일 후로 나타났으며 박엽지와 부직포 사이의 흡착성의 차이도 역시 없었고, 백탄보드의 보관성 효과가 약 2배 좋았다. 결과적으로 백탄보드의 종류(혼합형, #40-60형)나 박엽지와 부직포 오버레이 백탄보드간의 신선도 유지효과의 차이는 없었다.

• 한국의류학회지
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• 제39권1호
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• pp.121-132
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• 2015

All aspects of clothing, including color, are a visible form of expression that carries invisible value. The purpose of this work is to study the expression of resistance in the white Hanbok in modern culture, specifically after the 1980s. Koreans have traditionally revered white color and enjoyed wearing white clothes. In Korea, white represents simplicity, asceticism, sadness, resistance against corruption, and the pursuit of innocence. This paper looks at: (i) the universal and traditional values of the color white, (ii) the significance of traditional white Korean clothing, (iii) the resistance characteristics of white in traditional Korean clothes, and (iv) the aesthetic values of white Hanbok. The white Hanbok often connotes resistance when it is worn in modern Korea. It is worn in folk plays, worn by shamans as a shamanist costume, worn by protestors for anti-establishment movements, and worn by social activists or progressive politicians. The fact that the white Hanbok has lost its position as an everyday dress in South Korea (instead symbolizing resistance when it is worn) is an unusual phenomenon. It shows that the white Hanbok, as a type of costume, is being used as a strong means of expression, following a change in the value of traditional costumes as it take on an expressive function.

• 펄프종이기술
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• 제38권2호
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• pp.1-8
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• 2006

In this study a process simulation method was used to analyze the accumulation phenomena of anionic starch in the process white water as the closure level of a fine paper making process is increased. A pilot paper machine was used as a model process. Dynamic simulations of the influence of white water usage ratio and uncoated broke addition ratio on the variation of process variable was monitored as a function of time. Results from the dynamic simulations showed that the volume of reservoirs affected the dynamic behavior of the process. The dynamic behavior of flow rate and dissolved starch concentration in process units were different from each other. The speed of the change of dissolved starch concentration in process units was depend on the starting point of the change of dissolved starch concentration, the length of circulation loop, and the volume of reservoirs.

• 한국정보기술학회 영문논문지
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• 제9권2호
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• pp.115-123
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• 2019

White-box cryptography is an implementation technique in order to protect secret keys of cryptographic algorithms in the white-box attack model, which is the setting that an adversary has full access to the implementation of the cryptographic algorithm and full control over their execution. This concept was introduced in 2002 by Chow et al., and since then, there have been many proposals for secure implementations. While there have been many approaches to construct a secure white-box implementation for the ciphers with SPN structures, there was no notable result about the white-box implementation for the block ciphers with Feistel structure after white-box DES implementation was broken. In this paper, we propose a secure white-box implementation for a block cipher SEED with Feistel structure, which can prevent the previous known attacks for white-box implementations. Our proposal is simple and practical: it is performed by only 3,376 table lookups during each execution and the total size of tables is 762.5 KB.

• 펄프종이기술
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• 제36권3호
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• pp.15-34
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• 2004

Diverse benefits such as reduction of fresh water consumption and effluent discharge, efficient use of raw materials and energy savings can be obtained by papermaking system closure. Closure of papermaking processes, however, causes many problems including reduction of the efficiency of additives, decrease of retention and dewatering, felt plugging, poor Paper quality, generation of slime and odor, poor vacuum efficiency, etc, and it has been recognized that accumulation of Inorganic and organic substances in the process white water is the prime cause of these problems. Therefore, technological developments for preventing accumulation of these detrimental substances are urgently required for Implementing papermaking system closure. Understanding of the accumulation phenomena of the inorganic and organic substances in the papermaking process white water is prerequisite for papermaking system closure. In this study a process simulation method was used to analyze the accumulation phenomena of anionic starch In the process white water as the closure level of a fine paper making process is increased. A pilot paper machine was used as a model process. Starch adsorption and desorption models were developed based on the concept of starch adsorption ratio, which was not considered in previous studies. Steady state simulation studies were carried out based on this model using a commercial simulator. In steady state simulation, the variation of dissolved starch concentration in each process unit was monitored as a function of white water usage for wire shower. The result of the steady state simulation showed that dissolved starch concentration and its increase ratio in Process units increased as white water usage ratio for wire shower increased.