• Title/Summary/Keyword: white paper

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The Characteristic Analysis of White Organic Light Emitting Diodes with Two-wavelength Materials at Emitting Layer (발광층에 2파장 재료를 갖는 백색 유기발광소자의 특성분석)

  • Kang, Myung-Koo;Shim, Ju-Yong;Oh, Hwan-Sool
    • 전자공학회논문지 IE
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    • v.45 no.1
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    • pp.1-6
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    • 2008
  • In this paper, the white organic LED with two-wavelength was fabricated using the NPB of blue emitting material and a series of orange color fluorescent dye(Rubrene) by vacuum evaporation processes. The structure of white OLED was ITO/NPB$(200{\AA})$NPB:Rubrene$(300{\AA})$/BCP$(100{\AA})/Alq_3(100{\AA})/Al(1000{\AA})$ and the doping concentration of Rubrene was 0.75 wt%. We obtained the white OLED with CIE color coordinates were x=0.3327 and y=0.3387, and the maximum EL wavelength of the fabricated white organic light-emitting device was 560 nm at applied voltage of 11 V, which was similar to NTSC white color with CIE color coordinates of x=0.3333 and y=0.3333. The turn-on voltage is 1 V, the light-emitting him-on voltage is 4 V. We were able to obtain an excellent maximum external quantum efficiency of 0.457 % at an applied voltage of 18.5 V and current density of $369mA/cm^2$.

Application of a Flashlight system for White LEDs Manufactured using a Reproduction Phosphor (재생 형광체로 제조한 백색 LED의 손전등 시스템에의 적용)

  • Ryu, Jang-Ryeol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.5195-5200
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    • 2014
  • White LEDs are expected to be applied widely as a lighting system. To make white LED chips, one requires a mixture with silicon and a phosphor coating on a LED blue chip. The process of preparing a mixture with silicon using phosphor involves the use of discarded phosphor in the chip process. Reducing the costs of chip production depends on many factors, such as the mixture errors, exposure over time of silicon, and changes in the characteristics of blue chip. This paper reports the characteristics of a white LED chip manufactured through a reproduction process of derelict phosphor. This method was applicable to a real LED flashlight. A derelict phosphor chip showed similar results to a normal white chip for the degradation of cd 3.2[Cd] and 3.6[Cd], color temperature, 57[K] and 58[K], and maximum white wavelength 444.3[nm] and 449.8[nm]. These results are expected to make ea great contribution to cost reduction.

Activation energy standardization of White LED Phosphor (White LED 형광체의 활성화 에너지 정형화)

  • Jang, In-Hyeok;Kim, Su-Kyoung;Han, Ji-Hoon;Lee, Chang-Hoon;Lim, Houng-Woo
    • Journal of Applied Reliability
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    • v.13 no.2
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    • pp.117-127
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    • 2013
  • In this paper, we studied the correlation between the activation energy($E_a$) of the raw materials and the structural characteristics of the White LED PKGs. The samples used in the study were composed of low power LED 3type and high power LED 5type. To calculate the activation energy($E_a$) of the White LED PKGs conducted three conditions of high temperature operation test based on the Arrhenius model. The number of samples used in the experiment is 10, respectively. The $T_j$ of Conditions and target specifics expressed $T_{j1}$, $T_{j2}$, $T_{j3}$. The activation energy ($E_a$) of the samples was calculated based on the value of the actually measured lifetime. We investigated the correlation between the activation energy ($E_a$) of the raw materials and the structural characteristics of the White LED PKGs. As a result, White LED PKGs activation energy($E_a$) value was confirmed that the material properties affected more than the structural characteristics of the LED PKGs and we found that activation energy of each LED Model has difference. Normally, The activation energy of phosphor of YAG type was indicated from 0.21 to 0.25[eV] and Silicate type was indicated from 0.12 to 0.16[eV]. According to the results, we confirmed that the activation energy of phosphor of YAG type is higher more than The activation energy of phosphor of Silicate type.

New Higher-Order Differential Computation Analysis on Masked White-Box AES (마스킹 화이트 박스 AES에 대한 새로운 고차 차분 계산 분석 기법)

  • Lee, Yechan;Jin, Sunghyun;Kim, Hanbit;Kim, HeeSeok;Hong, Seokhie
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.1
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    • pp.1-15
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    • 2020
  • As differential computation analysis attack(DCA) which is context of side-channel analysis on white-box cryptography is proposed, masking white-box cryptography based on table encoding has been proposed by Lee et al. to counter DCA. Existing higher-order DCA for the masked white box cryptography did not consider the masking implementation structure based on table encoding, so it is impossible to apply this attack on the countermeasure suggested by Lee et al. In this paper, we propose a new higher-order DCA method that can be applied to the implementation of masking based on table encoding, and prove its effectiveness by finding secret key information of masking white-box cryptography suggested by Lee et al. in practice.

A Stylized Font Rendering System for Black/White Comic Book Generation (흑백 만화 제작을 위한 스타일 폰트 설계 시스템)

  • Lee, Jeong-Won;Ryu, Dong-Sung;Park, Soo-Hyun;Cho, Hwan-Gue
    • The KIPS Transactions:PartA
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    • v.15A no.2
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    • pp.75-86
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    • 2008
  • Black/white comic rendering is one of the researches in the field of non-photorealistic rendering(NPR). Black/white comics have been produced manually as yet. But these previous systems require lots of time and manual work. So we propose the COmics Rendering system on VIdeo Stream (CORVIS) which transforms video streams into black/white comic cuts. Stylized font, one of comic representations, can be used to express onomatopoeic words and mimetic dialogue exaggeratively. But current comic generation systems do not provide enough effects of stylized font. This paper proposes a model for stylized fonts to express various effects. Effects of stylized fonts we proposed include geometric deformations. Thus we could represent stylized fonts on the still cut of movies and the background texture on a cuts of plain black/white comics. The final quality of our system produced is good enough to compare with manual black/white comics.

Germination and Radicle Elongation of Berseem , Subterranean and White Clover as Affected by NaCl and Temperature (NaCl 농도와 온도에 따른 Berseem , Subterranean 및 White Clover의 발아 및 유근신장)

  • 강진호;박진서;박정민
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.2
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    • pp.80-86
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    • 1995
  • High salinity common in reclaimed soil can reduce germination of crop seeds and aftermath its establishment and production. The experiment was done to measure germination and radicle elongation of berseem, subterranean, white clover and Italian ryegrass as Control under different temperature and NaCl concentrations. Onehundred seeds of berseem (Trifolium ulexandrinum cv. Bigbee). suberranean (T. suhterruneum, cv. Nungarin), white clover (T. repens, cv. Regal) and Italian ryegrass (Lolium mulriflorum, cv. Terafloum) were placed in petri dishes with a sheet of filter paper replaced every two days, and then exposed to 0, 12.5, 25. 50, 100 and 200mh4 of sodium chloride in darkened growth chambers controlled with 10, 15 and $20^{\circ}C$. Percent germination and radicle elongation were measured. Beneem clover showed greatest daily percent germination among the cloven. That of subterranean clover, moreover, was higher than that of white clover till 4 days after imbibition but the reverse result was true thereafter. Although germination of Italian ryegrass was delayed with decreased at 200mM of NaCl of $20^{\circ}C$. at 200mM of under$15^{\circ}C$ , and at higher than lOOmh4 of all level of temperature, respectively. Berseem clover had greatest radicle length under the same concentration of NaCl regardless of temperature treatment while radicle elongation of subterranean and white clover was repressed over 50-100mM of NaC1. The slope of linear regression equation between concentration of NaCl and percent germination declined under all temperature treatment in order of berseem, subterranean and white clover whereas the reverse result was showed in radicle length.

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Situation-awareness White Cane Using a Mobile Device (모바일기기를 이용한 상황인식-흰지팡이)

  • Jeon, Dong-Hee;Jeon, Jun-Uk;Beak, Hwa-Hyeon;Moon, Mi-Kyeong
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.11
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    • pp.167-173
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    • 2014
  • A white cane is used by many people who are blind or visually impaired. The studies and developments in the field of smart electronic white cane have been progressed to improve walking safety of the visually handicapped person. In this paper, we describe a situation-awareness white cane which support and guide walking of the visually handicapped person by giving information of surrounding situation through connection of a white cane and a mobile device. There are easily accessible buttons in the situation-awareness white cane. These buttons is connected with the mobile device by blue-tooth, so by pushing these buttons, the visually handicapped person can receive sound-guidance. As a result, the visually handicapped person can walk more safely by getting more information of situation.

Development of Inner Packaging Material for Maintaining the Freshness of Fruits and Vegetables

  • Won, Jong-Myoung;Song, Je-Yun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.39 no.1 s.119
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    • pp.64-68
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    • 2007
  • The oak and pine charcoal were used to develop the inner packaging material for maintaining the freshness of vegetables and fruits, and to investigate the possibility in the application for inner packaging. The effects of the charcoal type, species, particle size, and grammage on the adsorption efficiency of ethylene gas were studied. White charcoal has superior ethylene gas adsorption performance to those of black charcoal. Pine charcoal was superior to oak charcoal in the ethylene gas adsorption. Higher gas adsorption was obtained by the higher grammage sheet. The difference in the adsorption efficiency was not significant between ONP and KOCC.

A Comparative Analysis of Movie Versions of "Snow White" (동화 "백설 공주"를 영화화한 작품들의 비교분석)

  • Lee, Youn H.
    • Cartoon and Animation Studies
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    • s.30
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    • pp.245-262
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    • 2013
  • This paper analyzes three feature films that are based on Brothers Grimm's "Snow White": Disney's Snow White and the Seven Dwarfs (1937), Tarsem Singh's Mirror Mirror (2012), and Rupert Sanders' Snow White and the Huntsman (2012). Disney's animation, not the original literature, is the archetype of the later films. Grimm's fairy tail does not include the kiss of Prince Charming that saved Snow White which is, in fact, borrowed from "Sleeping Beauty", nor Snow White's rapport with animals. In Snow White and the Huntsman 's case, the costume of protagonist is similar with Disney's film and some shots are almost identical with Disney's version in terms of composition and angles. Nevertheless, these films show their originality with markedly different visual styles. Mirror Mirror and Snow White and the Huntsman have achieved reasonable success at the box office despite of relatively simple and predictable narratives due to the power of spectacle. While Disney's Snow White displays the model of witch that later becomes prototype of many movies, Mirror Mirror represents the unique magical world, a trompe-l'oell that can only done by director Tarsem, and Snow White and the Huntsman successfully visualizes Freudian concept of 'the uncanny' itself.

Studies on Manufacture of Hanji(Korean Paper) Sludge·Wood Particle Composite - I. Physical Properties of Hanji(Korean Paper)Sludge·Wood Particle Composite (한지(韓紙) 슬러지·목재(木材) 파티클 복합(複合)보드의 제조연구(製造硏究) - I. 한지(韓紙) 슬러지·목재(木材) 파티클 복합(複合)보드의 물리적(物理的) 성질(性質))

  • Lee, Phil-Woo;Lee, Hak-Lae;Son, Jung-Il
    • Journal of the Korean Wood Science and Technology
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    • v.29 no.2
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    • pp.109-117
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    • 2001
  • 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). In 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 physical properties of Hanji(Korean paper) sludge wood particle composite. The linear expansion of Hanji(Korean paper) sludge wood particle composite was not always increased, compared to control boards. For thickness swelling, PMDI-bonded composites had the lowest value, and thickness swelling of composite was generally decreased with the increase of Hanji sludge. The water absorption of white sludge wood particle composite had no tendency, hut that of black sludge wood particle composite was decreased with an increase of mixing ratio of Hanji sludge.

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