• Title/Summary/Keyword: Brightness Improvement

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EoP Bleaching of Mixed Office Wastepaper (MOW의 산소-알칼리 첨가 과산화수소 표백)

  • Kim, Seung-Ho;Lee, Hyung;Baek, Ki-Hyun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.3
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    • pp.46-52
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    • 2002
  • To produce the raw material used for printing and writing paper or high quality tissue, MOWs that were consisted of white ledger, colored ledger and old newspaper were bleached with EoP and EoPY(FAS) method, the EoP bleaching process gave the improvement in brightness and a high color removal efficiency. Especially, MOW B(initial brightness: 59.1% ISO) that contained much old newspaper showed the higher bleaching efficiency than those of MOW A(initial brightness: 68.3%). After EoPY(FAS) bleaching, MOW's brightness was increased from 68.3% ISO to 84.3∼84.0% ISO, and from 59.1% ISO to 78.7∼79.2% ISO, respectively. Also the tensile and burst index of bleached pulps decreased by 10∼30%. The tear index slightly decreased or halted at the same range as unbleached pulps.

Improvement of Papermaking Properties of Recycled Fiber with Enzyme (효소처리에 의한 재생섬유의 제지적성 개선)

  • 최윤성;원종명
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.33 no.1
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    • pp.30-37
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    • 2001
  • The effects of enzymatic treatment of recycled fiber were investigated to obtain the basic informations which can be used to improve the papermaking properties of recycled fiber. The recycled fibers were prepared by the repeated handsheet making and disintegrating of hardwood of hardwood and softwood kraft pulp. Novozym 342, Dinimax and Pulpzyme HC were used for enzymatic treatment. The change of fiber length distribution, freeness, contact angle and crystallinity of pulp were measured. The brightness, opacity, breaking and tear index of paper were also measured. The enzymatic treatment decreased long fiber fraction of recycled hardwood fiber, but increased long fiber fraction of recycled softwood fiber. Freeness was decreased with 0.1% enzyme and then increased again with the increase of th enzyme dosage. The improvement of flexibility of recycled fiber was obtained through the decrease of contact angle that is resulted from the decrease of crystallinity of fiber. Brightness and opacity were affected by the type of pulp and enzyme, and dosage of enzyme. Breaking length of recycled hardwood fiber was improved with enzyme treatment, but breaking length of recycled softwood fiber was decreased except for 0.01% Pulpzyme treatment. Tear index was decreased with enzymatic treatment and the lowest decrease was observed with the treatment to Pulpzyme.

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A Study on the Proper Illuminance Considering the Task Amenity of the Occupant in the Office Space (사무공간의 재실자의 작업면 쾌적성을 고려한 적정조도 도출)

  • Kim, In-Hye;Kim, Sung-Kyung;Hong, Won-Hwa
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.36 no.3
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    • pp.159-167
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    • 2020
  • For modern people who spend most of their time indoors, the indoor environment is very important. The efficiency of work depends on the amenity level of the occupants who use the office space. Therefore, the experiment was conducted to derive the proper illuminance according to the amenity level of the occupants. The experiment was conducted in an office in Chilgok County for 6 days. The illuminance of the indoor was changed every day, the feeling brightness of the occupants was measured every 10 minutes, the eye fatigue was measured every 30 minutes, and the overall illuminance and the work surface illuminance were measured every hour. Experimental results show that the feeling brightness is different depending on the position of the occupants. Also, it was found that the brightness survey preferred by the occupants required more proper illuminance than the brightness. In addition, it is considered that there is a correlation with indoor temperature and humidity as the eye fatigue of occupants. Brightness preference by time of day was analysis from feeling brightness of occupants and preference brightness of occupants, and then it was analyzed like eye fatigue to derive proper illuminance per hour. Based on these results, it can be utilized for improvement of eye amenity existing office space.

Fabrication and Optical Properties of Inorganic Electroluminescent Devices (무기전계발광 디스플레이 소자 제작 및 광학 특성 연구)

  • Lee, Jun-Young;Hwang, Jin-Ha
    • Journal of the Korean Ceramic Society
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    • v.46 no.3
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    • pp.317-322
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    • 2009
  • Statistical designs of experiments were applied in order to understand the effect of processing variables on the brightness of inorganic electroluminescent displays. The main effects and interaction of phosphor and dielectric layers are estimated to be statistically significant. Additional improvement was made on removing the pores in the thick films, using the defoaming in pastes and cold isostatic pressing in bonding the top and bottom parts of the inorganic electroluminescent devices. Such optimization contributed to the reduction in the corresponding threshold voltage and enhancement in the brightness.

Construction and actual material test of prism LGP not using function characteristic optical sheet for production of high brightness Back Light Unit

  • Han, J.M.;Yoon, D.K.;Park, D.S.;Oh, Y.S.;Bae, K.W.;Kim, Y.H.;Lim, Y.J.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1233-1235
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    • 2004
  • We have designed High Performance Prism LGP in 17 inch TFT-LCD. In test result to embody high brightness BLU in case of LGP of base and upper surface with 17 inch, thickness 8mm adding prism construct, it is superior brightness improvement than previous that of printing form about some 20% and in this course to embody actual material it succeeded prism LGP production by 17 inch injection form process.

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Neutral Deinking of Old Newsprints Contaminated with Flexo Ink

  • Hoon Ryu;Lee, Hak-Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.35 no.5
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    • pp.10-16
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    • 2003
  • Presence of small amount of old newspapers printed with waterbased flexographic inks leads to a significant loss of brightness of the deinked pulp by flotation process. Recently there has been an increased interests in employing neutral deinking processes to solve the problems associated with waterbased flexo ink. A comparative experimental study was performed to evaluate the efficiency of neutral deinking and conventional alkaline deinking for ONP furnishes contaminated with flexo ink. Effects of the deinking processes on pulp quality and white water characteristics were examined. It was shown that neutral deinking would provide significant improvement in brightness, yield, and freeness as compared with conventional alkaline deinking. There was no increase in brightness when OMG was added in the furnish up to 20 %, and it was attributed to the redeposition of flexo inks on chemical pulp fibers.

NEUTRAL DEINKING OF OLD NEWSPRINTS CONTAMINATED WITH FLEXO INK

  • Hoon Ryu;Lee, Hak-Lae
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 1999.04b
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    • pp.343-348
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    • 1999
  • Presence of small amount of old newspapers printed with waterbased flexographic inks leads to a significant loss of brightness of the deinked pulp by flotation process. Recently there has been an increased interests in employing neutral deinking processes to solve the problems associated with waterbased flexo ink. A comparative experimental study was performed to evaluate the efficiency of neutral deinking and conventional alkaline deinking for ONP furnishes contaminated with flexo ink. Effects of the deinking processes on pulp quality and white water characteristics were examined. It was shown that neutral deinking would provide significant improvement in brightness, yield, and freeness as compared with conventional alkaline deinking. Three was no increase change in brightness when OMG was added in the furnish up to 20%, and it was attributed to the redeposition of flexo inks on chemical pulp fibers.

Sequential Oxidative and Reductive Bleaching of MOW by the Addition of Thiourea (Thiourea 첨가에 의한 MOW의 산화-환원 연속 표백)

  • 김승호;안병준;백기현
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.34 no.3
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    • pp.38-45
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    • 2002
  • The effect of sequential oxidative-reductive bleaching on brightening of the MOWs is investigated. The improvement in brightnesses of MOWs is more effective in conventional PFAS bleaching than in P/T bleaching. There is no difference in the mechanical properties or the bleached pulps between PFAS and P/T sequences. Considering the brightness gains and bleaching chemicals cost, for the MOW A(Initial brightness: 68.3% ISO) containing 5% ONP and 20% colored paper, the P/T bleaching is more economical than the PFAS bleaching. However for MOW B(initial brightness: 59.1% ISO) containing 15% ONP and 35% colored paper, there is no difference in the bleaching efficiency between PFAS and P/T bleaching.

A new combined brightness/contrast control of a color monitor for improvement of user convenience (사용자 편의성을 높인 컬러모니터의 brightness/contrast 통합조절)

  • 박승옥;김홍석;백정기
    • Science of Emotion and Sensibility
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    • v.2 no.1
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    • pp.113-119
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    • 1999
  • brightness와 contrast의 적절한 조절은 자연색 재현 및 다양한 분위기 창출이 가능하여 디스플레이의 질을 향상시킬 수 있다. 디스플레이 사용자들은 OSD(On-Screen-Display)를 통해 brightness와 contrast상태를 임의로 조절할 수 있으나, 조절에 따른 영상의 변화를 예측하지 못하므로 이를 잘 활용하지 못하고 있다. 본 연구에서는 brightness와 contrast가 각각 영상에 미치는 영향을 분석하여 자연색 재현이 가능한 최적상태와 4가지의 감성적 분위기를 나타낼 수 있는 조절상태를 정의하였다. 5가지 조절상태를 OSD에 제시함으로써 사용자가 쉽게 영상의 이미지에 적합한 brightness와 contrast상태로 조절할 수 있어 제품에 대한 만족감을 높일 수 있는 brightness/contrast 통함 조절방법을 제안하였다.

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Single-Image Dehazing based on Scene Brightness for Perspective Preservation

  • Young-Su Chung;Nam-Ho Kim
    • Journal of information and communication convergence engineering
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    • v.22 no.1
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    • pp.70-79
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    • 2024
  • Bad weather conditions such as haze lead to a significant lack of visibility in images, which can affect the functioning and reliability of image processing systems. Accordingly, various single-image dehazing (SID) methods have recently been proposed. Existing SID methods have introduced effective visibility improvement algorithms, but they do not reflect the image's perspective, and thus have limitations that distort the sky area and nearby objects. This study proposes a new SID method that reflects the sense of space by defining the correlation between image brightness and haze. The proposed method defines the haze intensity by calculating the airlight brightness deviation and sets the weight factor of the depth map by classifying images based on the defined haze intensity into images with a large sense of space, images with high intensity, and general images. Consequently, it emphasizes the contrast of nearby images where haze is present and naturally smooths the sky region to preserve the image's perspective.